ENB (LTE) Feature Description for PKG 6.0.0_v1.0

eNB (LTE) Feature Description for PKG 6.0.0

Radio Access Network

Describes the concept, software release, dependency & limitation requirements, and its interconnection with the telecommunication network as a high level design.

Document Version 1.0 July 2016

Document Number: 2600-00J9HZGAP

© 2016 SAMSUNG Electronics Co. Ltd. All Rights Reserved. No part of this document may be photocopied, reproduced, stored in a retrieval system, or transmitted, in any form or by any means whether, electronic, mechanical, or otherwise without the prior written permission of SAMSUNG Electronics Co., Ltd. No warranty of accuracy is given concerning the contents of the information contained in this publication. To the extent permitted by law no liability (including liability to any person by reason of negligence) will be accepted by SAMSUNG Electronics Co., Ltd., its subsidiaries or employees for any direct or indirect loss or damage caused by omissions from or inaccuracies in this document. SAMSUNG Electronics Co., Ltd. reserves the right to change details in this publication without notice.

SNMTC-v3-0312

This manual should be read and used as a guideline for properly installing and/or operating the product. Owing to product variations across the range, any illustrations and photographs used in this manual may not be a wholly accurate depiction of the actual products you are using. This manual may be changed for system improvement, standardization and other technical reasons without prior notice. Samsung Networks documentation is available at http://www.samsungdocs.com

Contents Preface

vii Relevance ....................................................................................................................................... vii Conventions in this Document ....................................................................................................... vii New and Changed Information ......................................................................................................viii Revision History ................................................................................................................................ x Organization of This Document ...................................................................................................... xi Related Documentation .................................................................................................................. xi

Chapter 1

Air Performance Enhancement 1 LTE-ME2019, DL SU 2 × 2 MIMO (TM3 and TM4) ............................................................................ 1 LTE-ME2020, Rx Diversity ................................................................................................................. 7 LTE-ME2022, DL SU 4 × 4 MIMO (TM3 and TM4) .......................................................................... 10 LTE-ME2023, DL SU 4 × 2 MIMO (TM3 and TM4) .......................................................................... 16 LTE-ME3601, Uplink CoMP (JR) ...................................................................................................... 22 LTE-ME4003, FeICIC ....................................................................................................................... 27 LTE-ME4005, IRC ............................................................................................................................ 43 LTE-ME5012, TDD-FDD Carrier Aggregation (20 + 5) ..................................................................... 46 LTE-ME5016, TDD-FDD Carrier Aggregation (20 + 3) ..................................................................... 49 LTE-ME5110, FDD Carrier Aggregation (5 + 5) ............................................................................... 52 LTE-ME5111, FDD Carrier Aggregation (3 + 5) ............................................................................... 55 LTE-ME5112, FDD Carrier Aggregation (3 + 3) ............................................................................... 58 LTE-ME6003, Smart FeICIC ............................................................................................................. 61 LTE-ME6004, DL Smart ................................................................................................................... 70 LTE-ME6005, UL Smart (Interference Coordination for UL) ........................................................... 76 LTE-ME6009, Inter Cluster Smart Scheduler .................................................................................. 82 LTE-ME6017, Smart CRS-IC............................................................................................................. 88

Chapter 2

Call Control 91 LTE-SW0100, Support UE Category 0 ............................................................................................. 91 LTE-SW0101, Support for UE Category 1, 2, 3, and 4 ..................................................................... 96 LTE-SW0111, UE Counting per Category ...................................................................................... 100 LTE-SW0114, Enhancements for Diverse Data Applications ........................................................ 103 LTE-SW0315, Extended Access Barring (SIB14) ............................................................................ 107 LTE-SW0318, SIB Broadcast (SIB16) ............................................................................................. 112 LTE-SW0320, RRC Connection Management ............................................................................... 115 LTE-SW0321, UE Context Management ....................................................................................... 126 LTE-SW0322, E-RAB Management ............................................................................................... 134 LTE-SW0325, User Inactivity Timer Control ................................................................................. 142 LTE-SW0327, SIPTO Support ........................................................................................................ 149 LTE-SW0501, S1 Interface Management ...................................................................................... 157 LTE-SW0504, MME Selection and Load Balancing ....................................................................... 174 LTE-SW0505, Random Delayed S1 Setup for Load Distribution ................................................... 179 LTE-SW0510, Geo Redundancy of MME ...................................................................................... 183 LTE-SW0521, X2 Interface Management ..................................................................................... 189 LTE-SW3010, PDCP Sublayer Support .......................................................................................... 199 LTE-SW3011, Header Compression ROHCv1 (RTP, UDP, IP) ........................................................ 202 LTE-SW3052, Ciphering: Null/SNOW3G/AES ............................................................................... 207 LTE-SW4101, Capacity based Call Admission Control .................................................................. 210

eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

iii

Contents

LTE-SW4102, QoS based Call Admission Control ......................................................................... 223 LTE-SW4103, Preemption ............................................................................................................ 233 LTE-SW4106, Call Admission Control per QCI .............................................................................. 241 LTE-SW4201, Standard QCI Support ............................................................................................ 243 LTE-SW4202, Operator Specific QCIs Support ............................................................................. 247 LTE-SW4203, QCI to DSCP Mapping ............................................................................................. 251 LTE-SW4211, Application Aware QoS .......................................................................................... 255 LTE-SW5500, CA Call Control ....................................................................................................... 260 Chapter 3

Load Control 279 LTE-SW2001, Intra-LTE Mobility Load Balancing.......................................................................... 279 LTE-SW2020, Load Distribution over Backhaul Links ................................................................... 295 LTE-SW2104, eNB Overload Protection ....................................................................................... 298 LTE-SW2106, Delay Tolerant Access Processing for eNB Overload Control ................................ 301 LTE-SW2107, MME Overload Protection ..................................................................................... 306 LTE-SW2108, Smart Congestion Mitigation ................................................................................. 309

Chapter 4

Mobility Control 312 LTE-SW1002, Idle Mobility Support ............................................................................................. 312 LTE-SW1004, S1 Handover ........................................................................................................... 328 LTE-SW1005, X2 Handover ........................................................................................................... 337 LTE-SW1006, Data Forwarding ..................................................................................................... 349 LTE-SW1007, Inter-Frequency Handover ..................................................................................... 358 LTE-SW1014, RLF Triggered Handover ......................................................................................... 377 LTE-SW1015, Frequency-priority-based HO ................................................................................. 384 LTE-SW1017, Inter-Frequency Handover for CA .......................................................................... 400 LTE-SW1201, Idle Mobility to UTRAN .......................................................................................... 405 LTE-SW1207, CSFB to UTRAN with Redirection without SI .......................................................... 414 LTE-SW1301, Idle Mobility to GERAN .......................................................................................... 423 LTE-SW1309, CSFB to GERAN with Redirection without SI .......................................................... 428 LTE-SW2011, Service based Intra-LTE Handover ......................................................................... 437 LTE-SW2014, SPID based Dedicated Priority ................................................................................ 444

Chapter 5

RAN Sharing 453 LTE-SW5001, Multi-PLMN Support .............................................................................................. 453 LTE-SW5002, Flexible Radio Resource Configuration for RAN Sharing ........................................ 462

Chapter 6

Radio Scheduler 472 LTE-ME0508, Sounding Reference Signal ..................................................................................... 472 LTE-ME1101, PDSCH Resource Allocation .................................................................................... 477 LTE-ME1503, PUSCH Frequency Hopping .................................................................................... 481 LTE-ME1504, PUCCH Format ........................................................................................................ 487 LTE-ME3001, Power Control ........................................................................................................ 493 LTE-ME3002, Residual BLER aware UL Power Control ................................................................. 500 LTE-ME3005, DL Power Allocation ............................................................................................... 503 LTE-ME3101, HARQ in DL and UL ................................................................................................. 508 LTE-ME3201, Basic Link Adaptation ............................................................................................. 514 LTE-ME3203, Aperiodic CQI Reporting......................................................................................... 520 LTE-ME3206, Periodic Channel Status Reporting ......................................................................... 522 LTE-ME3301, Uplink Scheduler Enhancement ............................................................................. 527 LTE-ME3304, Scheduling with QoS Support ................................................................................. 529 LTE-ME3305, Semi-persistent Scheduling .................................................................................... 534 LTE-ME3307, UL Sub-frame Bundling .......................................................................................... 541 LTE-ME3309, Resource allocation enhancement for SIB ............................................................. 546


iv

Contents

LTE-ME3310, VoLTE concurrent rank adaptation ........................................................................ 550 LTE-ME3401, Paging DRX ............................................................................................................. 553 LTE-ME3402, Active DRX .............................................................................................................. 556 LTE-ME3503, CFI-based PUSCH adaptation ................................................................................. 562 Chapter 7

Radio Transmission 566 LTE-ME0102, FDD 3 MHz Bandwidth ........................................................................................... 566 LTE-ME0103, FDD 5 MHz Bandwidth ........................................................................................... 571 LTE-ME0107, TDD 20 MHz Bandwidth ......................................................................................... 576 LTE-ME0201, Frame Structure Type 1 (FDD) ................................................................................ 580 LTE-ME0203, Frame Structure Type 2 (UL/DL Configuration #1) ................................................. 583 LTE-ME0204, Frame Structure Type 2 (UL/DL Configuration #2) ................................................. 588 LTE-ME0214, Frame Structure Type 2 (SS Configuration #5) ....................................................... 593 LTE-ME0216, Frame Structure Type 2 (SS Configuration #7) ....................................................... 598 LTE-ME0403, Uplink 64 QAM Support ......................................................................................... 603 LTE-ME3010, Timing Advance Control ......................................................................................... 605

Chapter 8

SON 608 LTE-SO0101, Self-establishment .................................................................................................. 608 LTE-SO0120, Smart Scheduler IP AutoConfiguration ................................................................... 615 LTE-SO0201, Intra-LTE ANR .......................................................................................................... 625 LTE-SO0301, PCI AutoConfiguration ............................................................................................ 660 LTE-SO0401, RACH Optimization ................................................................................................. 675 LTE-SO0501, Intra-LTE MRO ......................................................................................................... 698 LTE-SO0601, Sleeping Cell Detection ........................................................................................... 718 LTE-SO0602, Cell Outage Compensation ..................................................................................... 724 LTE-SO0603, Sick Cell Detection................................................................................................... 733 LTE-SO0702, Coverage and Capacity Optimization ...................................................................... 738 LTE-SO0801, PA Bias Control ........................................................................................................ 745 LTE-SO0901, Minimization Drive Test Optimization .................................................................... 755

Chapter 9

Services 766 LTE-SV0105, eMPS (Enhancements for Multimedia Priority Service) Support ............................ 766 LTE-SV0202, ETWS (Earthquake and Tsunami Warning System) ................................................. 768 LTE-SV0301, A-GNSS (LPP) ........................................................................................................... 773 LTE-SV0302, Enhanced Cell ID ...................................................................................................... 775 LTE-SV0303, OTDOA ..................................................................................................................... 781 LTE-SV0401, Vocoder Rate Adaptation ........................................................................................ 789 LTE-SV0404, VoLTE Quality Enhancement ................................................................................... 795 LTE-SV0406, VoLTE Coverage Enhancement ................................................................................ 802 LTE-SV0501, eMBMS Basic Function ............................................................................................ 805 LTE-SV0502, MBMS Counting ...................................................................................................... 821 LTE-SV0503, Multicell and Multicast Coordination (MCE) ........................................................... 826 LTE-SV0504, eMBMS Resource Allocation ................................................................................... 835 LTE-SV0510, eMBMS Preemption ................................................................................................ 846 LTE-SV0511, eMBMS QoS ............................................................................................................ 850 LTE-SV0513, eMBMS Service Continuity(SIB15) .......................................................................... 854 LTE-SV0514, Adaptive Delay Reduction for eMBMS .................................................................... 859 LTE-SV0515, eMBMS Session Monitoring .................................................................................... 864 LTE-SV0516, eMBMS Unicast Fallback (Dynamic Switching between Unicast and Broadcast) ... 870 LTE-SV0517, eMBMS Service Restoration .................................................................................... 875 LTE-SV1400, TCP UL Congestion Control...................................................................................... 879


v

Contents

Chapter 10

System Test and Analysis 881 LTE-OM9001, Cell Traffic Trace .................................................................................................... 881 LTE-OM9002, Subscriber and Equipment Trace........................................................................... 888 LTE-OM9003, UE Throughput and RF information Trace ............................................................. 892 LTE-OM9004, CSL (Call Summary Log) Report ............................................................................. 900 LTE-OM9005, Packet Loss Detection over S1 ............................................................................... 904 LTE-OM9013, Interference and Interferer Detection (TDD) ........................................................ 907 LTE-OM9100, Key Performance Indexes ...................................................................................... 914 LTE-OM9101, L1 and L2 Counters ................................................................................................ 921


vi

Preface This document provides detailed descriptions of each feature in the PKG 6.0.0 software release. Some features, commands, parameters, or counters are not supported by all software releases or approved for all markets.

Relevance This manual applies to the following products/software. Name

Type

PKG 6.0.0

Software

Conventions in this Document Samsung Networks product documentation uses the following conventions.

Symbols Symbol

Description Indicates a task. Indicates a shortcut or an alternative method. Provides additional information. Provides information or instructions that you should follow to avoid service failure or damage to equipment. Provides information or instructions that you should follow to avoid personal injury or fatality. Provides antistatic precautions that you should observe.

Menu Commands menu | command This indicates that you must select a command on a menu, where menu is the name of the menu, and command is the name of the command on that menu.


vii

Preface

File Names and Paths These are indicated by a bold typeface. For example: Copy filename.ext into the /home/folder1/folder2/bin/ folder.

User Input and Console Screen Output Text Input and output text is presented in the Courier font. For example, context CLI commands are presented in bold small caps. For example, Type the RTRV-NE-STS command in the input field.

New and Changed Information This section describes information that has been added/changed since the previous publication of this manual.

The following table shows the new and enhanced features for PKG 6.0.0 comparing with PKG 5.0.0: Development Type

Feature ID, Name

New features

LTE-ME4003, FeICIC LTE-ME5012, TDD-FDD Carrier Aggregation (20 + 5) LTE-ME5016, TDD-FDD Carrier Aggregation (20 + 3) LTE-ME5111, FDD Carrier Aggregation (3 + 5) LTE-ME5112, FDD Carrier Aggregation (3 + 3) LTE-ME6003, Smart FeICIC LTE-ME6009, Inter Cluster Smart Scheduler LTE-ME6017, Smart CRS-IC LTE-SW0327, SIPTO Support LTE-SW4211, Application Aware QoS LTE-SW1015, Frequency-priority-based HO LTE-SW1017, Inter-Frequency Handover for CA LTE-SW5002, Flexible Radio Resource Configuration for RAN Sharing LTE-ME3002, Residual BLER aware UL Power Control LTE-ME3301, Uplink Scheduler Enhancement LTE-ME3310, VoLTE concurrent rank adaptation LTE-SO0120, Smart Scheduler IP AutoConfiguration LTE-SV0401, Vocoder Rate Adaptation LTE-SV0406, VoLTE Coverage Enhancement LTE-SV0502, MBMS Counting LTE-SV0510, eMBMS Preemption LTE-SV0516, eMBMS Unicast Fallback (Dynamic Switching between Unicast and Broadcast) LTE-SV1400, TCP UL Congestion Control LTE-OM9013, Interference and Interferer Detection (TDD)


viii

Preface Development Type

Feature ID, Name

Enhanced features

LTE-ME2019, DL SU 2 × 2 MIMO (TM3 and TM4) LTE-ME2022, DL SU 4 × 4 MIMO (TM3 and TM4) LTE-ME2023, DL SU 4 × 2 MIMO (TM3 and TM4) LTE-ME3601, Uplink CoMP (JR) LTE-ME5110, FDD Carrier Aggregation (5 + 5) LTE-ME6004, DL Smart LTE-ME6005, UL Smart (Interference Coordination for UL) LTE-SW0100, Support UE Category 0 LTE-SW0101, Support for UE Category 1, 2, 3, and 4 LTE-SW0315, Extended Access Barring (SIB14) LTE-SW0320, RRC Connection Management LTE-SW0322, E-RAB Management LTE-SW0325, User Inactivity Timer Control LTE-SW0501, S1 Interface Management LTE-SW0504, MME Selection and Load Balancing LTE-SW0521, X2 Interface Management LTE-SW3010, PDCP Sublayer Support LTE-SW3011, Header Compression ROHCv1 (RTP, UDP, IP) LTE-SW4101, Capacity based Call Admission Control LTE-SW4102, QoS based Call Admission Control LTE-SW4201, Standard QCI Support LTE-SW4202, Operator Specific QCIs Support LTE-SW5500, CA Call Control LTE-SW2001, Intra-LTE Mobility Load Balancing LTE-SW1005, X2 Handover LTE-SW1006, Data Forwarding LTE-SW1007, Inter-Frequency Handover LTE-SW1014, RLF Triggered Handover LTE-SW1201, Idle Mobility to UTRAN LTE-SW1207, CSFB to UTRAN with Redirection without SI LTE-SW1309, CSFB to GERAN with Redirection without SI LTE-ME1503, PUSCH Frequency Hopping LTE-ME1504, PUCCH Format LTE-ME3001, Power Control LTE-ME3005, DL Power Allocation LTE-ME3101, HARQ in DL and UL LTE-ME3305, Semi-persistent Scheduling LTE-ME3307, UL Sub-frame Bundling LTE-ME3402, Active DRX LTE-SO0101, Self-establishment LTE-SO0201, Intra-LTE ANR LTE-SO0301, PCI AutoConfiguration LTE-SO0401, RACH optimization LTE-SO0501, Intra-LTE MRO LTE-SO0801, PA Bias Control LTE-SO0901, Minimization Drive Test Optimization LTE-SV0302, Enhanced Cell ID LTE-SV0501, eMBMS Basic Function


ix

Preface Development Type

Feature ID, Name LTE-SV0503, Multicell and Multicast Coordination (MCE) LTE-SV0504, eMBMS Resource Allocation LTE-SV0511, eMBMS QoS LTE-SV0513, eMBMS Service Continuity (SIB15) LTE-OM9001, Cell Traffic Trace LTE-OM9002, Subscriber and Equipment Trace LTE-OM9003, UE Throughput and RF information Trace LTE-OM9004, CSL (Call Summary Log) Report LTE-OM9005, Packet Loss Detection over S1 LTE-OM9101, L1 and L2 Counters

Revision History The following table lists all versions of this document. Document Number

Product/Software Version

Document Version

Publication Date

Remarks

2600-00J9HZGAP

PKG 6.0.0

1.0

July 2016

First version


x

Preface

Organization of This Document Section

Title

Description

Chapter 1

Air Performance Enhancement

This chapter describes PKG 6.0.0 LTE features related to Air Performance Enhancement.

Chapter 2

Call Control

This chapter describes PKG 6.0.0 LTE features related to Call Control.

Chapter 3

Load Control

This chapter describes PKG 6.0.0 LTE features related to Load Control.

Chapter 4

Mobility Control

This chapter describes PKG 6.0.0 LTE features related to Mobility Control.

Chapter 5

RAN Sharing

This chapter describes PKG 6.0.0 LTE features related to RAN Sharing.

Chapter 6

Radio Scheduler

This chapter describes PKG 6.0.0 LTE features related to Radio Scheduler.

Chapter 7

Radio Transmission

This chapter describes PKG 6.0.0 LTE features related to Radio Transmission.

Chapter 8

SON

This chapter describes PKG 6.0.0 LTE features related to SON.

Chapter 9

Services

This chapter describes PKG 6.0.0 LTE features related to Services.

Chapter 10

System Test and Analysis

This chapter describes PKG 6.0.0 LTE features related to System Test and Analysis.

Related Documentation eNB (OAM) Feature Description for PKG 6.0.0 eNB (Transport) Feature Description for PKG 6.0.0


xi

Chapter 1

Air Performance Enhancement

LTE-ME2019, DL SU 2 × 2 MIMO (TM3 and TM4) INTRODUCTION Multiple antenna techniques aim to improve data robustness or provide an increase in data rates by utilizing special signal structure and exploiting un-correlated fading channels for each transmitted signal. In case of two transmit antennas on an eNB and two receive antennas on the same UE, is known downlink 2 × 2 singleuser MIMO. Figure below depicts the concept of single user MIMO using m transmit and n receive antennas.

As shown in the figure above, each receiver side antenna receives a composite signal made up of transmitted signals modified by their channels. Under specific channel conditions, the transmitter can structure the transmitted signals to, either send modified copies of the same transmission (transmit diversity) or, send different transmission (spatial multiplexing). The former case provides signal robustness and the latter provides increase in data rate.

BENEFIT Provides improvement in the cell capacity and throughput, as UEs with good channel conditions can benefit from the multiple streams transmission.

Serves improved throughput or reliable communication due to the multiple streams transmission.

DEPENDENCY 

HW dependency


1

Chapter 1 Air Performance Enhancement

oSupport Channel Cards: There is no limitation on channel card to support this feature.



Related Radio Technology oE-UTRAN (LTE)



Prerequisite Features oLTE-ME0501 (Cell-specific Reference Signal)

LIMITATION None

SYSTEM IMPACT Performance and Capacity This feature increases the UE downlink throughput by 2-layer spatial multiplexing according to the feedback rank information. Moreover, TM3 and TM4 rank adaptation provides appropriate pre-coder in time-varying channel. Interfaces When transmission mode is changed, the eNB sends the RRC Connection Reconfiguration message for UE to change the Transmission Mode IE.

FEATURE DESCRIPTION Samsung supports the DL SU-MIMO Spatial Multiplexing (SM) in both Transmission Mode 3 (open-loop SM) and Transmission Mode 4 (closed-loop SM) employing 2 × 2 antenna configuration, that is, 2 transmit eNB antennas and 2 receive UE antennas.

Transmit Diversity Transmit diversity is default MIMO mode in LTE. This redundancy leads to increase in signal-to-noise ratio and therefore, signal robustness. Transmission Mode 2 provides transmit diversity by transmitting single PDSCH codeword using four antennas.

Spatial Multiplexing In spatial multiplexing, there is no signal redundancy as there is with transmit diversity; antenna ports transmit different symbols. Two modes that provide spatial diversity are TM3 and TM4. TM3 uses a predetermined CDD-based precoding and favorable to high speed UEs. TM4 uses a codebook-based precoding and favorable to low speed UEs because scheduler adopts the best pre-coder per UE based on the pre-coder feedback by UE. For both TM3 and TM4, rank adaptation based on feedback rank information is supported so that the most appropriate number of transmission layers (and codewords) can be adopted. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

2

Chapter 1 Air Performance Enhancement Mode

Description

Antenna Ports

Layer

Codewords

Channel Rank

UE Feedback

TM3

Open loop spatial multiplexing with cyclic delay diversity

2

2

2

2

CQI, RI

TM4

Closed loop spatial multiplexing with precoding matrix

2

2

2

2

CQI, RI, PMI

Transmission Mode 3 TM3 is spatial multiplexing scheme that uses pre-determined precoding matrix. The process of applying pre-coding is defined in 3GPP specification TS 36.211. Open loop spatial uses Channel Quality Information (CQI) and Rank Indication (RI) information feedback from UE. TM3 is suitable for scenarios when the UE is in good channel condition. A stationary or pedestrian speed UE in good RF coverage scenario gets the most benefit from this mode. Codewords, layers mapping in open loop spatial multiplexing (TM3) for 2 antenna ports are tabulated as follows. Number of Codewords

Number of Layers

2

2

CW, Layer Mapping

Transmission Mode 4 TM4 is spatial multiplexing scheme that uses PMI index feedback from UE, to construct downlink PDSCH codeword to maximize signal-to-noise ratio at UE receiver. A PMI index is a pointer to a set of pre-coding weights that are applied to downlink codewords prior to transmission. The process of applying pre-coding is defined in 3GPP specification TS 36.211. TM 4 is suitable for scenarios when the UE is in slow time-varying channel because there is a delay associated with a PMI report from UE and a corresponding downlink transmission that utilizes the reported PMI index. A stationary or pedestrian speed UE in good RF coverage scenario gets the most benefit from this mode. Codewords, layers mapping in closed-loop spatial multiplexing (TM4) for 4 antenna ports are tabulated as follows.


3

Chapter 1 Air Performance Enhancement Number of Codewords

Number of Layers

1

1

2

2

CW, Layer Mapping

SYSTEM OPERATION This section describes how to configure the feature in Samsung system and provides associated key parameters, counters, and KPIs.

How to Active Preconditions Ensure that this condition is met before enabling this feature:



DL_ANT_COUNT must be set equal to or greater than n2TxAntCnt.

Activation Procedure Run CHG-CC-INF and set DL_CRS_PORT_COUNT to 2 to enable 2 × 2 SUMIMO. Deactivation Procedure Run CHG-CC-INF and set DL_CRS_PORT_COUNT to another value.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Description of RTRV-CELL-IDLE/CHG-CELL-IDLE Parameter

Description

DL_ANT_COUNT

This parameter is the number of Tx antennas used by an operating cell.

Parameter Description of RTRV-CC-INF/CHG-CC-INF Parameter

Description

DL_CRS_PORT_COUNT

This parameter is the number of downlink CRS ports that are applied to the


4

Chapter 1 Air Performance Enhancement Parameter

Description channel card.

Configuration Parameters To configure the feature setting, run the associated commands and set the key parameters. Parameter

Description

CELL_NUM

This parameter describes user-defined cellId.

DL_MIMO_MODE

This parameter specifies transmission mode. Each one is corresponding to certain multiple antenna techniques. TM1: Single-antenna port (port 0), DCI format 1 or 1A is used. TM2: Transmit diversity, DCI format 1 or 1A is used. TM3: Open-loop spatial multiplexing, DCI format 2A or 1A is used. TM4: Closed-loop spatial multiplexing, DCI format 2 or 1A is used. TM5: MU-MIMO, DCI format 1D or 1A is used. It is a test mode and it is not supported. TM6: Closed-loop rank-1 precoding, DCI format 1B or 1A is used. It is a test mode and it is not supported. TM7: Single-antenna port (port 5), DCI format 1 or 1A is used. It is supported for only 8T8R TDD. TM8: Dual layer transmission, or single-antenna port (port 7/port 8), DCI format 2B or 1A is used. It is supported for only 8T8R TDD. TM9: UE specific RS based transmission (Rel-10) [Related Specifications] 3GPP TS 36.213

MIMO_MODE_SWITCHING

Flag for dynamic switching between TM3 and TM4 0: switching off 1: switching on

Counters and KPIs There are no specific counters or Key Performance Indicators (KPIs) associated with this feature.

REFERENCE [1] 3GPP TS 36.201 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; General description‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.214 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; Measurements‟


5


[6] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


6


LTE-ME2020, Rx Diversity INTRODUCTION Currently, receive diversity techniques are not specified in the LTE specification, because receive diversity places no requirements in the transmitter. However, it needs to be noted that receive diversity enables to make better quality on uplink received signal. Samsung eNB support Rx diversity using Minimum Mean Squared Error (MMSE) combining with Interference Rejection Combining (IRC) receiver.

BENEFIT Rx diversity enables to communicate in the more reliable transmission condition.

DEPENDENCY None

LIMITATION None

FEATURE DESCRIPTION In Rx diversity, the receiver needs to combine multiple streams from different antenna into a single stream. The challenge here is how to use the information from all the antennas effectively. In fact, it is just a matter of choosing the appropriate weight for each received signals (see the following figure).

There are multiple ways to choose the weight of receiver, however, Samsung eNB uses linear MMSE (LMMSE) receiver with IRC to suppress inter-cell interference.


7


Linear Minimum Mean Squared Error (LMMSE) Receiver with Interference Rejection Combining (IRC) To obtain receive diversity, Samsung eNB considers LMMSE criterion with IRC. This advanced receiver employing IRC is effective in improving the cell-edge user throughput. The IRC receiver utilizes the covariance of interference and noise factors of multiple receiver branches, and combines the received signals for multiple receiver branches so that the Mean Square Error (MSE) between the combined signal and the desired signal is minimized, instead of Maximal Ratio Combining (MRC). The specific combining criterion is as follows:

1 The channel estimator of the eNB receiver estimates the channel of the desired signal, and generates the covariance matrix of interference and noise. oEstimate the channel matrix of the desired signal

oEstimate the covariance matrix of interference and noise

2 Using the estimated channel and the covariance matrix, MMSE weight is calculated to perform IRC. oMinimum Mean Squared Error (MMSE) criterion

oMMSE criterion achieves the optimal balance the noise enhancement and interference suppression oCombined weight

3 Interference rejection is achieved by MMSE combining at the eNB receiver.

The IRC scheme based on MMSE criterion achieves an optimal balance of noise enhancement and interference suppression. Hence, IRC provides the enhanced performance to UEs at the cell boundary that experience serious interference from other cell. The receive diversity can be obtained from combining the calculated weight with received signals for each receiver path.

SYSTEM OPERATION How to Activate This feature is an optional feature and can be activated and deactivated with the parameter IRC_ENABLE. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

8


Default IRC_ENABLE is FALSE (IRC OFF) (IRC_ENABLE = 0). Run CHG-PUSCH-IDLE to set IRC_ENABLE to TRUE (IRC ON) (IRC_ENABLE = 1).

Run RTRV-PUSCH-IDLE to retrieve the configuration information for IRC_ENABLE.

The operator can disable this feature by setting IRC_ENABLE to FALSE (IRC OFF)' (IRC_ENABLE = 0).

Key Parameters RTRV-PUSCH-IDLE/CHG-PUSCH-IDLE Parameter

Description

IRC_ENABLE

This parameter is used to enable to use IRC 0: False (IRC OFF) 1: True (IRC ON)


REFERENCE [1] 3GPP TS 36.201 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE physical layer; General description [2] Goldsmith, A. J. Wireless communications. Cambridge University Press, 2005


9


LTE-ME2022, DL SU 4 × 4 MIMO (TM3 and TM4) INTRODUCTION Multiple antenna techniques improve data robustness or provide an increase in data rates by utilizing special signal structure and exploiting un-correlated fading channels for each transmitted signal. In case of four transmit antennas on an eNB and four receive antennas on the same UE, it is known as downlink 4 × 4 singleuser MIMO. Figure below depicts the concept of single user MIMO using m transmit and n receive antennas.

As shown in the figure above, each receiver side antenna receives a composite signal made up of transmitted signals modified by their channels. Under specific channel conditions, the transmitter can structure the transmitted signals to, either send modified copies of the same transmission (transmit diversity) or, send different transmission (spatial multiplexing) or combination of both. Transmit diversity provides signal robustness and spatial multiplexing increases data rate.

BENEFIT 

Provides improvement in the cell capacity and throughput, as UEs with good channel conditions can benefit from the multiple streams transmission.



Serves improved throughput or reliable communication due to the multiple streams transmission.

DEPENDENCY 



10


LIMITATION 

4Tx RU



A UE with at least category 5 supporting 4 layer

SYSTEM IMPACT Performance and Capacity DL SU 4 × 4 MIMO functionality supports 4-layer spatial multiplexing, and thereby increases peak rate and capacity of cell/UE compared to DL SU 2 × 2 MIMO. You can select transmission mode for 4 × 4 MIMO with DL_MIMO_MODE.

FEATURE DESCRIPTION Samsung supports the DL SU-MIMO Spatial Multiplexing (SM) in both Transmission Mode 3 (open-loop SM) and Transmission Mode 4 (closed-loop SM) employing 4 × 4 antenna configuration, that is, 4 transmit eNB antennas and 4 receive UE antennas.

Transmission Mode 3 TM 3 is spatial multiplexing scheme that uses pre-determined precoding matrix. The process of applying pre-coding is defined in 3GPP specification TS 36.211. Open loop spatial multiplexing uses Channel Quality Information (CQI) and Rank Indication (RI) information feedback from UE. TM 3 is suitable for scenarios when the UE is in good channel condition. A stationary or pedestrian speed UE in good RF coverage scenario will get the most benefit from this mode. Codewords, layers mapping in open loop spatial multiplexing (TM3) for 4 antenna ports are tabulated as follows. Number of Codewords

Number of Layers

1

2

2

2

CW, Layer Mapping


11


Number of Layers

CW, Layer Mapping

3

4

Transmission Mode 4 TM 4 is spatial multiplexing scheme that uses PMI index fed-back from UE, to construct downlink PDSCH codeword to maximize signal to noise ratio at UE receiver. A PMI index is a pointer to a set of pre-coding weights that are applied to downlink code words prior to transmission. The process of applying pre-coding is defined in 3GPP specification TS 36.211. TM 4 is suitable for scenarios when the UE is in slow time-varying channel because there is a delay associated with a PMI report from UE and a corresponding downlink transmission that utilizes the requested PMI index. A stationary or pedestrian speed UE in good RF coverage scenario gets the most benefit from this mode. Codewords, layers mapping in close-loop spatial multiplexing (TM4) for 4 antenna ports are tabulated as follows. Number of Codewords

Number of Layers

1

1

CW, Layer Mapping

2

2

2


12


Number of Layers

CW, Layer Mapping

3

4


How to Activate Preconditions Ensure that this condition is met before enabling this feature:






Description

DL_ANT_COUNT


Parameter Description of RTRV-CC-INF/CHG-CC-INF


13


Description

DL_CRS_PORT_COUNT

This parameter is the number of downlink CRS ports that are applied to the channel card.

Configuration Parameters To configure the feature setting, run the associated commands and set the key parameters. Parameter

Description

CELL_NUM


DL_MIMO_MODE


MIMO_MODE_SWITCHING

Flag for dynamic switching between TM3 and TM4 0: switching OFF 1: switching ON


REFERENCE [1] 3GPP TS 36.201 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; General description‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.214 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; Measurements‟


14




15


LTE-ME2023, DL SU 4 × 2 MIMO (TM3 and TM4) INTRODUCTION Multiple antenna techniques improve data robustness or provide an increase in data rates by utilizing special signal structure and exploiting un-correlated fading channels for each transmitted signal. In case of four transmit antennas on an eNB and two receive antennas on the same UE, known as downlink 4 × 2 single-user MIMO. Figure depicts the concept of single user MIMO using m transmit and n receive antennas.

As shown in the figure above, each receiver side antenna receives a composite signal made up of transmitted signals modified by their channels. Under specific channel conditions, the transmitter can structure the transmitted signals to, either send modified copies of the same transmission (transmit diversity) or, send different transmission (spatial multiplexing). The former case provides signal robustness and the latter provides increase in data rate.

BENEFIT 

Provides improvement in the cell capacity and throughput, as UEs with good channel conditions can benefit from the multiple streams transmission.



Serves improved throughput or reliable communication due to the multiple streams transmission.

DEPENDENCY 

HW dependency oOthers: 4T4R RRU is required





16




Prerequisite Features oLTE-ME0501 (Cell-specific Reference Signal)

LIMITATION None

SYSTEM IMPACT Performance and Capacity This feature increases the UE downlink throughout by 2-layer spatial multiplexing according to the feedback rank information. Moreover, TM3 and TM4 rank adaptation provides appropriate pre-coder in time-varying channel. Interfaces When transmission mode is changed, the eNB sends the RRC Connection Reconfiguration message for UE to change the Transmission Mode IE.

FEATURE DESCRIPTION Samsung supports the DL SU-MIMO Spatial Multiplexing (SM) in both Transmission Mode 3 (TM3: open loop SM) and Transmission Mode 4 (TM4: closed-loop SM) employing either 4 × 2 antenna configuration that is 4 transmit eNB antennas and 2 receive UE antennas.

Transmit Diversity Transmit diversity is default MIMO mode in LTE. This redundancy leads to increase in signal-to-noise ratio and therefore, signal robustness. Transmission Mode 2 provides transmit diversity by transmitting a single PDSCH codeword using 4 antennas.

Spatial Multiplexing In spatial multiplexing, there is no signal redundancy as with transmit diversity; antenna ports transmit different symbols. Two modes that provide spatial diversity are TM3 and TM4. TM3 uses a predetermined CDD-based precoding and favorable to high speed UEs. TM4 uses a codebook-based precoding and favorable to low speed UEs because scheduler adopts the best pre-coder per UE based on the pre-coder fed-back by UE. For both TM3 and TM4, rank adaptation based on fedback rank information is supported so that the most appropriate number of transmission layers (and codewords) can be adopted. Mode

Description

Antenna Ports

Layer

Codewords

Channel Rank

UE Feedback

TM3

Open loop spatial multiplexing with cyclic delay diversity

4

2

2

2

CQI, RI


17

Chapter 1 Air Performance Enhancement Mode

Description

Antenna Ports

Layer

Codewords

Channel Rank

UE Feedback

TM4

Closed loop spatial multiplexing with precoding matrix

4

2

2

2

CQI, RI, PMI

Transmission Mode 3 TM3 is spatial multiplexing scheme that uses pre-determined precoding matrix. The process of applying pre-coding is defined in 3GPP specification TS 36.211. Open loop spatial uses Channel Quality Information (CQI) and Rank Indication (RI) information fed-back from UE. TM3 is suitable for scenarios when the UE is in good channel condition. A stationary or pedestrian speed UE in good RF coverage scenario gets the most benefit from this mode. Codewords, layers mapping in open loop spatial multiplexing (TM3) for 4 antenna ports are shown in the table below. Number of Codewords

Number of Layers

2

2

CW, Layer Mapping

Transmission Mode 4 TM4 is spatial multiplexing scheme that uses PMI index feedback from UE, to construct downlink PDSCH codeword to maximize signal to noise ratio at UE receiver. A PMI index is a pointer to a set of pre-coding weights that are applied to downlink codewords prior to transmission. The process of applying pre-coding is defined in 3GPP specification TS 36.211. TM 4 is suitable for scenarios when the UE is in slow time-varying channel because there is a delay associated with a PMI report from UE and a corresponding downlink transmission that utilizes the reported PMI index. A stationary or pedestrian speed UE in good RF coverage scenario gets the most benefit from this mode. Codewords, layers mapping in closed-loop spatial multiplexing (TM4) for 4 antenna ports are shown in table below. Number of Codewords

Number of Layers

CW, Layer Mapping


18


Number of Layers

1

1

2

2

CW, Layer Mapping


How to Activate Preconditions Ensure that this condition is met before enabling this feature:






Description

DL_ANT_COUNT


Parameter Description of RTRV-CC-INF/CHG-CC-INF Parameter

Description


19


Description

DL_CRS_PORT_COUNT

This parameter is the number of downlink CRS ports that are applied to the channel card.

Configuration Parameters To configure the feature setting, run the associated commands and set the key parameters. Parameter Description of RTRV-DL-SCHED/CHG-DL-SCHED Parameter

Description

CELL_NUM


DL_MIMO_MODE


MIMO_MODE_SWITCHI NG

Flag for dynamic switching between TM3 and TM4 0: switching OFF 1: switching ON


REFERENCE [1] 3GPP TS 36.201 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; General description‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.214 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; Measurements‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

20




21


LTE-ME3601, Uplink CoMP (JR) INTRODUCTION The increasing demand for high quality of service, coupled with the wireless spectrum shortage, requires advanced wireless communications techniques to enhance the cell-edge throughput. LTE release 11 standard introduces UL Coordinated Multipoint (CoMP) JR scheme, which utilizes multiple receive antennas from multiple antenna site locations. Samsung‟s intra-eNB UL CoMP implementation is not dependent on Release 11. In the UL CoMP JR scheme, PUSCH transmitted by the UE is received jointly at multiple points and combined using IRC at a time to improve the received signal quality.

BENEFIT This feature utilizes multiple Rx antennas from multiple points, which belong to the same channel card, to enhance the received UL signal quality especially for cell-edge UEs. Figure below depicts the benefit of UL CoMP JR at cell edge.

DEPENDENCY 



22


LIMITATION 

This feature supports up to 4Rx combining for 2Rx antenna configuration system or up to 8Rx combining for 4Rx antenna configuration system.



This feature is not supported for Pico eNB.



(Rel10 support HW only limitation) When UL CoMP JR is enabled, the maximum number of cells that eNB supports can be reduced.



(Rel10 support HW only limitation): When UL CoMP support inter-modem chip UL CoMP JR within a channel card, some parameters (Rx antenna count and channel BW) should be set to the same value among the modem chips.

SYSTEM IMPACT Performance and Capacity The UL CoMP (JR) feature improves cell-edge user throughput by diversity reception from multiple points.

FEATURE DESCRIPTION Figure below depicts the intra-eNB uplink CoMP architecture.

UL CoMP JR architecture is based on joint processing of the signals received at multiple points to improve cell-edge user throughput by diversity reception. In the Samsung UL CoMP JR, the received data at each reception point within UL CoMP set is transferred to the serving cell for joint processing. This results in radio gains for UEs at cell edge.

Feature Operation UL JR CoMP is implemented in Modem and uses IRC to combine uplink PUSCH signals. Samsung UL CoMP JR operates within the group of cells called UL CoMP Set. All UEs within the UL CoMP enabled cell are considered to be candidates for combining, that is, there is no further classification into sector overlap and nonoverlap UEs.


23


Cell-based Path Selection UL CoMP JR can be done using the cell-based path selection. The UE transmits data to all receive points and the receive points forward the received data to the serving cell before decoding. The system decides the best points among the receive points of UL CoMP Set and perform Rx Combining (IRC) including the serving points and the best points. The best points are selected based on PUSCH SINR cell-based selection using average SINR of each cell. The procedure of the cell-based selection is as follows:

All paths of the serving cells are selected for combining. Additional path required for combining is selected after performing a search. The cell-based selection algorithm performs the best neighbour cell search of all the neighbour cells within UL CoMP set belongs to the serving cell.

The SINR for the neighbouring cells are calculated. Neighbour cell with largest average PUSCH SINR of all its paths is selected. Combining is done for all the paths of the serving cell and all the paths of the selected neighbour cell.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Ru CHG-ULCOMPJR-IDLE to change the configuration required to operate UL CoMP (JR).

Run RTRV- ULCOMPJR-IDLE to retrieve the configuration information required to operate UL CoMP (JR).

Run CHG-ULCOMPJR-IDLE and set UlCompJrOnOff = 1 for desired cell number to activate UL CoMP. Deactivation Procedure Run CHG-ULCOMPJR-IDLE and set UlCompJrOnOff = 0 for desired cell number to deactivate UL CoMP.


24


Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ULCOMPJR-IDLE/RTRV-ULCOMPJR-IDLE Parameter

Description

CELL_NUM

The cell number. This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity provided to the carrier per system is 1 FA/3 Sector, up to 3 cells are supported

UL_COMP_JR_ON_OFF

The parameter indicates whether to activate UL CoMP JR 0: UL CoMP JR is de-activated 1: UL CoMP JR is Activated

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ULCOMPJR-IDLE/RTRV-ULCOMPJR-IDLE Parameter

Description

UlCompJrEnhancementFlag

The parameter indicates whether to apply UL CoMP JR enhancement algorithm. 0: UE Battery Saving Preferred Mode 1: UL Throughput Enhancement Preferred Mode


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

25


[6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.819 „Coordinated multi-point operation for LTE physical layer aspects‟ [9] 3GPP TR 36.913 „Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN)‟


26


LTE-ME4003, FeICIC INTRODUCTION In Heterogeneous Networks (HetNet), low power base stations (microcells or pico cells) are overlaid on the well-planned macro cells with the aim of obtaining higher cell-splitting gain from the reduced communication range. However, the unplanned low power base stations and the strong interference from the macro cell can cause severe near-far problem to the UEs connected to the low power base stations. To alleviate the inter-cell interference problem and provide improved offloading performance through the low power base stations, 3GPP Rel-10 standard introduces Enhanced Inter-cell Interference Coordination (eICIC), which is based on Almost Blank Subframes (ABS) and Cell Range Expansion (CRE). Moreover, to increase the benefit of eICIC, 3GPP Rel-11 standard introduces Further Enhanced ICIC (FeICIC) that adds the requirement of CRS interference cancellation at UE receivers.

BENEFIT Edge UE throughput enhancement by means of ABS. Macro-to-pico offloading by means of CRE. All UEs including legacy UEs (which do not support eICIC/FeICIC) take the benefit of ABS.

Rel-10 eICIC UEs take the benefit of CRE as well. Rel-11 FeICIC UEs take the benefit of CRE and CRS-IC as well.

DEPENDENCY 

Required Network Elements oThe UE must support eICIC/FeICIC




LIMITATION 

Commercial release is subject to change considering commercial UE release to support eICIC and it needs additional IOT with commercial UE.



eICIC UE is required to support FGI 115 defined in TS 36.331.


27




FeICIC UE is required to support crs-InterHandl-r11 in UE-EUTRACapability IE defined in TS 36.331 and TS 36.306 as well as the requirement for eICIC UE.



When macro and pico eNB vendors are different in operator's network, it is required to discuss about FeICIC operation between both them.

SYSTEM IMPACT Performance and Capacity This feature enhances the system capacity in the heterogeneous network. Load imbalance between the macro and pico eNBs can decrease the resource utilization in the network. When the macro eNB load is very low, it can share its resource to the pico eNBs within the coverage. On the other hand, even if the macro eNB load is high, it can share its resource to the pico eNBs in the case that the macro eNB load is offloaded to the pico eNBs. Coverage This feature can change the pico eNB coverage, when Cell Range Extension (CRE) is operated. Interface This feature uses mainly X2 interface to share the load information of neighboring cells:

Load Information message: ABS Information IE, Invoke indication IE. Resource Status Response message: Downlink ABS Status IE.

FEATURE DESCRIPTION eICIC is firstly defined in 3GPP release 10 specification, which is a function to coordinate interference between the macro and pico eNBs. The eICIC is also beneficial for solving a traffic load's imbalance in heterogeneous network scenario and mitigating interference for UEs in the pico cell edge. The eICIC is mainly composed of two different functions of ABS and CRE. The use of ABS involves the eNB reducing their transmission during certain subframes or the eNB would have zero transmissions during ABS ideally. However, some transmissions are required for backwards compatibility with 3GPP release 8 and 9 devices. Transmissions are blanked by not scheduling PDCCH and PDSCH during these subframes.


28


Even blanked subframes require a transmission of the cell specific reference signal within both the control and data regions. In addition, the ABS also requires a transmission of the synchronization signals and the Physical Broadcast Channel (PBCH). If the high power macro eNB generates ABS, then the signal quality is improved for the low power pico eNB. Even though ABS function can reduces the spectral efficiency of the transmitting macro eNB, it provides the potential to increase the overall network capacity if the interference coordination is carefully managed. In heterogeneous network scenario, the intention of launching the pico eNBs is to offload traffic from macro eNB to increase the system capacity. As a result, when the macro eNB becomes overloaded, it would make sense to offload the macro UEs (MUE) near the pico coverage into pico eNB. This can be done even if the UE is receiving a better signal from the macro eNB. The expansion of the range of the pico cell is termed as CRE. Firstly, to enable eICIC, the operator needs to configure the eICIC feature flag to be enabled and eICIC partner macro cell's ECGI on the pico eNBs for associating with a macro cell. When these parameters are configured in the pico eNB, the pico eNB forwards an eICIC partner requesting message to the neighboring macro cell via the X2 interface. This message is sent to neighboring macro cell for requesting eICIC partnership and the use of ABS. After receiving eICIC partner requesting message, the macro cell checks whether this partner requesting is available or not. When the partnership requesting is acceptable, the macro cell sends the eICIC partnership acceptance using another X2-AP: LOAD INFORMATION message. If the ABS pattern has already been used for existing partner pico eNBs, current ABS pattern information is included in the LOAD INFORMATION message. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

29


When currently no ABS pattern information is available, all 0 bitmap is sent for only notifying eICIC partnership acceptance.

If the macro cell does not accept the eICIC partnership, it sends the X2-AP:LOAD INFORMATION message including ABS information with ABS Inactive flag to requesting pico eNB. The macro eNB rejects the eICIC partnership requesting in one of the following cases:

eICIC feature flag is off. The number of eICIC partner pico eNBs is more than the maximum value to be configured.

The target cell ID included in the X2-AP: LOAD INFORMATION message does not match with the macro cell own ECGI. When the pico eNB receives the eICIC partnership reject message from the macro cell, it tries to re-establish the eICIC partnership under the configured number of retry. The macro and pico cells to be associated as eICIC partner start a resource status reporting initiation procedure to request providing their partner's RESOURCE STATUS UPDATE messages. This procedure involves a 2-way handshake using the RESOURCE STATUS REQUEST and RESOURCE STATUS RESPONSE messages. The RESOURCE STATUS REQUEST message includes the report characteristics to indicate that ABS status and Composite Available Capacity information are requested at the target eNBs. The RESOURCE STATUS REQUEST message can define the reporting periodicity at which target eNB should provide reports. As depicted in figure below, the target eNB responds with RESOURCE STATUS RESPONSE message to notify whether the target eNB can report any of the requested measurements. The target eNB then starts periodic reporting of load information using the RESOURCE STATUS UPDATE message.


30


The content of the RESOURCE STATUS UPDATE message is presented in table below. Information Elements eNodeB 1 Measurement Identity eNodeB 2 Measurement Identity Cells to Report

List Composite Available Capacity Group

Downlink

Cell Capacity Class Capacity Value

ABS Status

Downlink ABS Status Usable ABS Pattern Information

Both the measurement identities of the initiating and the target eNBs are included within the RESOURCE STATUS UPDATE message. The Composite Available Capacity (CAC) defines the amount of resources that are available relative to the total E-UTRAN resources. The CAC allows the macro and pico cells to evaluate whether or not they can offload their load to each other. The capacity value provides a percentage measure of the available resources within a cell. A value of 0 means that no resources are available, whereas a value of 100 indicates that all resources are available. The reported capacity value can be weighted by the ratio of the cell capacity class values to account for the relative capacity of each cell. The downlink ABS status defines the percentage of used ABS resources from within the set of usable ABS. The usable ABS pattern bitmap defines the set of ABS, which the pico cell has been able to use. The ABS Status allows the macro cell to evaluate whether or not it can reduce the number of configured ABS and consequently increase its own capacity. The macro cell updates ABS pattern based on own load of macro cell and eICIC partner pico cells load at every period to be configured. When macro cell decides ABS pattern to be updated, it sends the updated ABS information in LOAD INFORMATION message to all partner pico cells. If pico cell receives the updated ABS pattern, it reflects the information in scheduling for UEs located on pico cell edge. Samsung eICIC pre-configures several of 40 bits of ABS patterns to be applied, and these ABS patterns are designed not to be influence on legacy control signaling. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

31


To decide a specific ABS pattern, the macro needs to calculate ABS ratio, which means the amount of resources to be required for pico CRE UEs among all available amount of resources. The basic information to calculate ABS ratio is CAC and Downlink ABS Status (DAS), and macro cell received these information from RESOURCE STATUS UPDATE from partner pico cells. In release 10 version of TS 36.423, the ABS information has been added to X2-AP: Load information message as shown in the following table. Information Elements Cell Information Item (1 to Number of cells at source eNB)

Cell Identity ABS Information (3GP release 10)

ABS Pattern Information Bitmap Number of Cell Specific Antenna Ports Measurement Subset Bitmap ABS Inactive

Invoke Indication (3GPP release 10)

The ABS pattern information bitmap defines a sequence of bits. In the case of FDD, the bitmap has a length of 40 bits so spans 4 radio frames. The ABS information also specifies the number of antenna ports used for the cell specific reference signal. This allows the receiving pico cells to estimate the impact of interference from the cell specific reference signal during ABS. The measurement subset bitmap within the ABS information is used to signal a subset of the ABS pattern information bitmap. This bitmap has the same length as the ABS pattern bitmap and is used to indicate which ABS subframes are recommended for UE measurements, for example, the set of subframes during which the UE should measure the serving cell RSRP and RSRQ. In heterogeneous network, the problem is that the number of UEs connected to the pico cells is much smaller than that of macro cell resulting in inefficient resource utilization. It is beneficial for the network to bias handover preferentially towards the pico cells, for example, add a handover offset to the pico cell RSRP so that the UE preferentially selects a pico cell even when it is not the strongest cell. This method is called CRE. Although CRE enables higher user offloading from macro cell on to pico cells, different problems can arise because the UE serving pico cell is not its strongest cell. The UEs connecting to the pico cell with large-bias CRE can suffer from severe interference from the aggressor macro cell since the eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

32


received signal power of the macro cell is larger than that of pico cell for such UEs. This kind of interference scenario requires interference coordination and 3GPP standard of release 10 version introduces time domain eICIC via ABS technique. It is covered in previous section, and this section will explain CRE in main.



CRE feature flag: The CRE function can be operator-configurable and CRE feature flag needs to be turned on, to operate CRE function.



CRE UE management: To offload UE between eICIC partner macro and pico cells, macro and pico cells manage their own CRE UEs who are candidates to be offloaded into target eICIC partner cell. The CRE UE is defined as macro CRE UE for macro cell and pico CRE UE for picocell. These CRE UEs are eICIC feature (or FeICIC feature) supportable UE, however, legacy UE (that is, release 8 or 9 UE) is not candidate of CRE UE.



CRE UE offloading: The macro and pico cells decide whether their own CRE UEs need to be offloaded or not, based on the offloading conditions per every configured period. If the offloading conditions are fulfilled for macro cell or pico cell, macro cell or pico cell initiates UE offloading procedure. The macro cell triggers the offloading when macro load is over the configured threshold and pico load is below the configured threshold. This means that macro offloads the CRE UE to partner pico in macro load imbalance and pico can serve these CRE UEs using blanked subframes (ABS) for enhancing the network performance. Whereas, the pico cell triggers the offloading when pico load is over the configured threshold and macro load is below the configured threshold. This means that pico offloads the CRE UE to partner macro in pico load imbalance and macro can serve these CRE UEs with returning ABS back to macro for enhancing the network performance. When the offloading conditions are satisfied at macro or pico, eNB firstly find the forced handover available UEs after receiving measurement report from its connected UEs. If there are candidate UEs to be handed over into eICIC partner cell, it performs handover procedure for candidate UEs until the offloading condition is released. These procedures are included in Mobility Load Balancing (MLB) function between macro and partner pico. If MLB is set to off or there is no forced handover available UE, even after receiving measurement reports from its connected UEs, it needs to modify the handover triggering condition by changing the mobility parameter (CRE bias).


33




CRE bias modification: When the UE offloading is triggered, however, the CRE UE cannot be offloaded to the eICIC partner cells by the MLB function; the initiating eNB adjusts its own handover triggering threshold. The initiating eNB uses the X2-AP: MOBILITY CHANGE REQUEST message to request the target eNB to adjust its handover threshold. The content of the MOBILITY CHANGE REQUEST message is presented in table below.

Information Elements eNodeB 1 Cell Identity eNodeB 2 Cell Identity eNodeB 1 Mobility Parameter

Handover Trigger Change

eNodeB 2 Proposed Mobility Parameter

Handover Trigger Change

Cause

Cell identities are specified for both initiating and target eNBs. The eNB 1 mobility parameter specifies a change to the handover triggering threshold, which the initiating eNB has already applied for handovers between the initiating and target eNB. The eNB 2 proposed mobility parameter specifies a suggested change to the triggering threshold being applied for handovers from the target eNB to the source eNB. The cause value within the MOBILITY CHANGE REQUEST message specifies the reason for the requested change, for example, load balancing. If the proposed handover triggering threshold is accepted, the target eNB responds using X2-AP: MOBILITY CHANGE ACKNOWLEDGE message. Even after finishing mobility parameter modification, the eNB does not explicitly handover UEs to target cells. Cell Individual Offset (CIO) value is adjusted between eICIC function and adjust handover thresholds are only changed for CRE UEs. The adjustment of handover thresholds results in UEs in the high loaded cell being more likely to handover to the less loaded neighbor cell.


34


If the proposed handover triggering threshold is refused, the target eNB responds using X2-AP: MOBILITY CHANGE FAILURE message. This message can specify upper and lower limits for changes to the handover triggering threshold. These can be used if the source eNB was requesting a change, which was too large. When using ABS, the eNB can use RRC signalling to provide 3GPP release 10 UE with instructions regarding the subframes to make measurements. Measurement results can vary significantly for pico cell UE located towards the edge of coverage. The pico cell UE can be provided with instructions to complete measurements during only the macro cell ABS subframes. This provides the pico cell with knowledge of the radio condition during those ABS subframes. 3GPP Release 10 terminals support configuration of time-domain restrictions for the following measurements:



Time domain ICIC RLM/RRM measurement subframe restriction for the serving cell: The measurement subframe pattern primary cell information presented in TS 36.311 is sent to a 3GPP release 10 UE using dedicated RRC message. This information element provides the UE with instruction regarding the set of subframes to use for Radio Link Monitoring (RLM) and Radio Resource Management (RRM) measurements of the serving cell. Instructing the UE to complete RLM during ABS subframes helps to avoid radio link failure being detected non-ABS subframes when the levels of downlink interference are relatively high. Completing RRM measurements during ABS subframes qualifies the radio conditions, which can be experienced if the UE is scheduled during those subframes.



Time domain ICIC RRM measurement subframe restriction for neighboring cells: Release 10 UE can be provided with instructions regarding the set of subframes to use for intra-frequency neighbor cell RRM measurements. If the PCI belonging to a neighbor is listed then the UE completes RSRP and RSRQ measurements for that neighbor during the specified subframes.



Time domain ICIC CSI measurement subframe restriction: Release 10 UE can also be provided with instructions regarding the set of subframes to use when generating Channel State Information (CSI). CSI include CQI, PMI and RI feedback to the serving eNB. The UE is provided with 2 measurement subframe patterns for CSI measurements. This allows the eNB to receive CSI feedback based on both ABS and non-ABS subframes, i.e. one subframe pattern can specify a set of ABS subframes while the other subframe pattern can specify a set of non-ABS subframes. The eNB then has sufficient information to schedule resources during both ABS and non-ABS subframes.

The network can configure these measurement restrictions for 3GPP Release 10 UEs with dedicated RRC signalling. As the aforementioned UE measurement restrictions cannot be configured for 3GPP Releases 8 and 9 legacy UEs, such terminal types may experience lower performance than 3GPP Release 10 UEs in networks with eICIC enabled. The main enhancement in rel-11 is to provide the UE with Cell-specific Reference Symbol (CRS) assistance information of the aggressor macro cells using dedicated RRC message in order to aid the UE located on pico cell edge to mitigate macro CRS interference. Obviously, only release 11 UE to support crs-interfHnadl-r11 defined in UE capability can interpret this CRS assistance information. In order to eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

35


define proper CRS-based measurements and improve demodulation for time domain ICIC with CRE bias, it was necessary to define signaling support indicating which neighbor cells have ABS configured. With 3GPP Release 11, RadioResourceConfigDedicated IE may optionally include a neighCellsCRSInfo field. neighCellsCRSInfo includes the following information of the aggressor cell(s):

Physical Cell ID Number of used antenna ports (1, 2, 4) MBMS subframe configuration When pico send RRC connection reconfiguration (RRC connection setup/RRC connection Re-establishment) message, it includes neighCellsCRSInfo on message to FeICIC supportable UE only.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure FeICIC operates by establishing eICIC partnership among a macro cell and pico cells within the macro cell coverage. To activate this feature and eICIC partnership establishment, do the following: oRun CHG-DL-EICIC and set EICIC_FLAG to True.

eICIC partnership starts when the macro cell‟s E-UTRAN Cell Global Identifier (ECGI) is entered as the pico cell EICIC_FLAG is set to True. If the macro cell‟s EICIC_FLAG is set to True and the number of the connected partner pico cells is smaller than the maximum number of pico cell partners, eICIC partnership can be established. To configure the maximum number of the pico cell partners that can be established by one macro cell, do the following: oRun CHG-DL-EICIC and set MAX_NUM_OF_PARTNER.

When eICIC is enabled, if CRE_FLAG is setting to ON, UEs in the CRE area between partners can be offloaded by handing over to partners via the Cell Individual Offset (CIO) change. Comparison of loads and thresholds of eICIC partners automatically decide offloading. If the load of the: oMacro cell is bigger than THR_CRE_OFFLOAD configured in the macro cell and the load of the pico cell is smaller than THR_CRE_OFFLOAD_PARTNER configured in the macro cell, the macro cell can offload its CRE UEs onto the pico cell. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

36


oPico cell is bigger than THR_CRE_OFFLOAD configured in the pico cell and the load of the macro cell is smaller than THR_CRE_OFFLOAD_PARTNER configured in the pico cell, the macro cell can offload its CRE UEs onto the macro cell.

ABS pattern is periodically determined and updated based on the load of the macro cell and the partner pico cells. Deactivation Procedure To deactivate this feature and eICIC partnership establishment, do the following:

Run CHG-DL-EICIC and set EICIC_FLAG of any of the eICIC partners to False.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated command and set the key parameter. Parameter Descriptions of CHG-DL-EICIC/RTRV-DL-EICIC Parameter

Description

EICIC_FLAG

This parameter is ON/OFF value of eICIC function.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-MACEICIC-CTRL/CHG-MACEICIC-CTRL Parameter

Description

T_ABS_PATTERN_UPDATE

The period for the ABS pattern update.

Common parameters for macro and pico cells Parameter Descriptions of RTRV-DL-EICIC/CHG-DL-EICIC Parameter

Description

CRE_FLAG

This parameter is ON/OFF value of CRE function. This parameter can be individually switched, however, the CRE function to operate, EICIC_FLAG needs to be set to True in both macro cell and its pico partner cell.

MAX_CRE_CIO_CHANGE_WAIT

This parameter specifies the number of times that satisfies CRE Offloading decision continuously.

THR_CRE_OFFLOAD

This parameter specifies the threshold (Macro/Pico) for offloading. For macro-to-pico offloading, macro load should be higher than THR_CRE_OFFLOAD, and the partner pico load should be lower than THR_CRE_OFFLOAD_PARTNER. For pico-to-macro offloading, pico load should be higher than THR_CRE_OFFLOAD, and the partner macro load should be lower than THR_CRE_OFFLOAD_PARTNER.


37


Description

THR_CRE_OFFLOAD_PARTNER

This parameter specifies the threshold (Macro/Pico) for offloading. For macro-to-pico offloading, macro load should be higher than THR_CRE_OFFLOAD, and the partner pico load should be lower than THR_CRE_OFFLOAD_PARTNER. For pico-to-macro offloading, pico load should be higher than THR_CRE_OFFLOAD, and the partner macro load should be lower than THR_CRE_OFFLOAD_PARTNER.

EICIC_BOUNDARY

Specify the maximum CIO value for eICIC UE.

FEICIC_BOUNDARY

Specify the maximum CIO value for FeICIC UE.

Parameters only for macro cell Parameter

Description

MAX_NUM_OF_PARTNER

The maximum the number of Pico Cells which can be made a partnership in one macro cell.

T_CRE_STATUS_UPDATE

This parameter is the term for CRE status update.

THR_CRE_ACT_MACRO

Threshold for CRE activation. For activating CRE, the Macro cell load should be above the threshold.

THR_CRE_ACT_PICO

Threshold for CRE activation. For activating CRE, the pico cell load should be lower than the threshold.

THR_CRE_UE_RATIO

Threshold for CRE activation. For activating CRE, the ratio of CRE UEs in the macro cell should be larger than the threshold.

THR_CRE_DEACT_ABS_FULL

Threshold for CRE deactivation. For deactivating CRE, ABS Full should be lower than this parameter value to be CRE deactivation. (macro cell dedicated parameter) * ABS Full = Number of RBs usage for Pico CRE UEs / Number of RBs usage for Macro UEs + Number of RBs usage for UEs of all Pico partners

Parameters only for pico cell Parameter

Description

PARTNER_MCC

This parameter is Mobile Country Code (MCC) of partner cell, which should be set for the partnership.

PARTNER_MNC

This parameter is Mobile Network Code (MNC) of partner cell, which should be set for the partnership.

PARTNER_CELL_IDENTITY

This parameter is Macro Cell Identity of partner cell, which should be established for the partnership.

T_PARTNERSHIP_GUARD

This parameter specifies the waiting time(s) to resume the partnership establishment request, in case of the specified number of consecutive failures.

T_PARTNERSHIP_RETRY

This parameter specifies the interval (ms) between two consecutive partnership establishment requests, in case of failure with the former request.

PARTNERSHIP_TX_COUNT

This parameter specified the maximum number of consecutive partnership establishment requests, in case of failure with the former request.

EICIC_SINR_ESTIMATE_ENABLE

This parameter configures SINR estimation function based on periodic MR for legacy UE, when eICIC function is activated.

Counters and KPIs Table below outlines the main counters associated with this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

38

Chapter 1 Air Performance Enhancement Family Display Name

Type Name

Type Description

EICIC

PartnershipCount

The average count of Partner Cell in Partnership

EICICCapaUECount

The count of UE supported FGI 115

CompositeAvailCapa

The average Capacity Value of Composite Availability Capacity

DLABSstatus

The average ratio of used ABS resource

CREUECount

The average count of CRE UE per partner Cell

EICICHOAtt

The number of HO attempts of eICIC UE after the HO is triggered by CRE Offloading

EICICHOSucc

The number of successful HOs of eICIC UE that were triggered by CRE Offloading.

FeICICHOAtt

The number of HO attempts of FeICIC UE after the HO is triggered by CRE Offloading

FeICICHOSucc

The number of successful Hos of FeICIC UE that were triggered by CRE Offloading.

EICICCIOAvg

Average eICIC CIO value for Pico partner cell

EICICCIOMin

Minimum eICIC CIO value for Pico partner cell

EICICCIOMax

Maximum eICIC CIO value for Pico partner cell

FeICICCIOAvg

Average FeICIC CIO value for Pico partner cell

FeICICCIOMin

Minimum FeICIC CIO value for Pico partner cell

FeICICCIOMax

Maximum FeICIC CIO value for Pico partner cell

AvgABSNum

The average number of ABS pattern uses during the collection interval.

ABSBin0

The ratio of macro cells to which an ABS pattern was not allocated during the collection interval.

ABSBin5

The use rate for the ABS pattern with an ABS ratio of 5/40 relative to all ABS patterns that have been applied to macro cells during the collection interval.

ABSBin6


ABSBin7


ABSBin8


ABSBin9


ABSBin10

The use rate for the ABS pattern with an ABS ratio of 10/40 relative to all ABS patterns that

EICIC_PARTNERSHIP

EICIC_ABS


39


Type Name

Type Description have been applied to macro cells during the collection interval.

ABSBin11


ABSBin12


ABSBin13


ABSBin14


ABSBin15


ABSBin16


ABSBin17


ABSBin18


ABSBin19


ABSBin20


ABSBin21


ABSBin22


ABSBin23



40


Type Name

Type Description

AvgABSNumForTdd


ABSBin0ForTdd


ABSBin4ForTdd

The use rate for the ABS pattern of TDD with an ABS ratio of 4/40 relative to all ABS patterns that have been applied to macro cells during the collection interval.

ABSBin5ForTdd


ABSBin6ForTdd


ABSBin7ForTdd


ABSBin8ForTdd


ABSBin9ForTdd


ABSBin10ForTdd


ABSBin11ForTdd


ABSBin12ForTdd


ABSBin13ForTdd


REFERENCE [1] 3GPP TS36.300, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[3] 3GPP TS36.423 Evolved Universal Terrestrial Radio Access Network (EUTRAN); X2 application protocol (X2AP)


42


LTE-ME4005, IRC INTRODUCTION Advanced receivers provide an implementation method to enhance further the capacity of the LTE system. A typical example is the Minimum Mean Squared Error (MMSE) receiver with Interference Rejection Combining (IRC). The ability of an IRC receiver to suppress interference is a function of many factors including the number and strength of the interfering signals and the number of receive antennas. Samsung eNB supports interference rejection combining based on MMSE criterion to provide the improved performance at cell boundary users that experience serious interference from other cells.

BENEFIT An operator can achieve the better quality of signal and improve system performance by cancelling the interference at eNB receiver.

DEPENDENCY AND LIMITATION Limitation This feature is not supported for indoor Smallcell.

FEATURE DESCRIPTION The advanced receiver employing IRC is effective in improving the cell-edge user throughput. The IRC receiver utilizes the correlation of the interference of multiple receiver branches, and combines the received signals for multiple receiver branches so that Mean Square Error (MSE) between the combined signal and the desired signal is minimized instead of Maximal Ratio Combining (MRC). In uplink, the eNB receiver utilizes IRC scheme, which is based on MMSE criterion to support interference cancellation function.

Interference Rejection Combining (IRC) The eNB receiver performs interference rejection combining to support interference cancellation as follows.

1 The channel estimator of eNB receiver estimates the channel of the desired signal, and generates the covariance matrix of interference and noise. oEstimate the channel matrix of the desired signal

oEstimate the covariance matrix of interference and noise eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

43


2 Using the estimated channel and the covariance matrix, MMSE weight is calculated to perform IRC. oMMSE criterion:

oMMSE criterion achieves the optimal balance the noise enhancement and interference suppression oCombined weight

3 Interference rejection is achieved by MMSE combining at the eNB receiver.

IRC scheme based on MMSE criterion achieves an optimal balance of noise enhancement and interference suppression. Hence, IRC provides the enhanced performance to UEs at the cell boundary that experience serious interference from other cell.

SYSTEM OPERATION How to Activate This is an optional feature and can be activated and deactivated with the IRC_ENABLE.

Run RTRV-PUSCH-IDLE command to retrieve the configuration information for IRC_ENABLE. Default IRC_ENABLE is False (IRC OFF, IRC_ENABLE = 0)'.

Run CHG-PUSCH-IDLE command to set IRC_ENABLE to True (IRC ON, IRC_ENABLE = 1)'.

The operator can disable this feature by setting IRC_ENABLE to False (IRC OFF, IRC_ENABLE = 0)'.

Key Parameters CHG-PUSCH-IDLE/RTRV-PUSCH-IDLE Parameter

Description

IRC_ENABLE

This parameter determines whether to enable or disable the use of IRC. 0: False (IRC OFF) 1: True (IRC ON)


44



REFERENCE [1] 3GPP TS 36.201 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer; General description [2] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation [3] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [4] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


45


LTE-ME5012, TDD-FDD Carrier Aggregation (20 + 5) INTRODUCTION The TDD-FDD Carrier Aggregation (20 + 5) feature enables an eNB to aggregate with TDD 20 MHz Carrier Component and FDD 5 MHz Component Carrier. The purpose of multiple CCs aggregation is to have wider channel bandwidth, which helps operators to increase bitrates for end-users.

BENEFIT With this feature, the operator can combine individual CCs from different band and bandwidths. This ensures that all the spectrum resources are utilized effectively across the network for improving efficiency and achieving higher peak throughputs.

DEPENDENCY 

HW dependency oOthers: CA can be restricted depending on the HW configuration.






Prerequisite Features oLTE-SW5500 (CA Call Control)



Others oThe UE needs to support this feature.

LIMITATION 

Device needs to support this feature.



FDD PCell DL/UL and TDD SCell DL only.

SYSTEM IMPACT Interdependencies between Features Interdepended Feature: LTE-SW5500, CA Call Control


46


For carrier aggregation, the operation mode and system configuration are performed by using the LTE-SW5500 feature. Refer to the CA Call Control for the configuration associated with this feature. Performance and Capacity Carrier aggregation increases the system capacity for end-users by utilizing the available spectrum resources effectively across the network. Refer to the CA Call Control feature for key parameter and detail information on counters associated with this feature. Coverage Carrier aggregation allows end users to access the network through multiple component carriers. Thus, the cell coverage can be increased for those CA users compared with the single-carrier users.

FEATURE DESCRIPTION The Samsung eNB supports a combination of TDD 20 MHz CC and FDD 5 MHz CC in downlink. TDD-FDD CA only supports Inter-band Non-contiguous CA. Figure below depicts the 20 + 5 aggregated LTE channels.

For detailed description of CA functionality and its operational procedures, refer to LTE-SW5500: CA Call Control feature. The eNB shall not perform the following configuration for the UE RRCConnected to TDD cell (pre-Rel.12 CA).

SCell addition with FDD SCell Measurement configuration for SCell addition: Event A4 measurement

SYSTEM OPERATION This section describes how to configure the feature in Samsung system and provides associated key parameters, counters, and KPIs. Refer to the System Operation section of LTE-SW5500: CA Call Control feature for configuration, key parameter, and detailed information on counters associated with this feature.


47


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.912 „Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)‟


48


LTE-ME5016, TDD-FDD Carrier Aggregation (20 + 3) INTRODUCTION The TDD-FDD Carrier Aggregation (20 + 3) feature enables an eNB to aggregate with TDD 20 MHz and FDD 3 MHz Component Carriers (CCs). The purpose of multiple CCs aggregation is to have wider channel bandwidth, which helps operators to increase bitrates for end-users.

BENEFIT With this feature, the operator can combine individual CCs from different band and bandwidths. This ensures that all the spectrum resources are utilized effectively across the network for improving efficiency and achieving higher peak throughputs.

DEPENDENCY 

HW dependency oOthers: CA could be restricted depending on the HW configuration.









Others oThe UE needs to support this feature.

SYSTEM IMPACT Interdependencies between Features Interdependent Feature: LTE-SW5500, CA Call Control For carrier aggregation, the operation mode and system configuration are performed by using the LTE-SW5500 feature. Refer to CA Call Control for the configuration associated with this feature.


49


Performance and Capacity Carrier aggregation increases the system capacity for end-users by utilizing the available spectrum resources effectively across the network. Refer to CA Call Control feature for key parameter and detailed information on counters associated with this feature. Coverage Carrier aggregation allows end users to access the network through multiple component carriers. Thus, the cell coverage can be increased for those CA users compared with the single-carrier users.

LIMITATION 

Device needs to support this feature.



FDD PCell DL/UL and TDD SCell DL only.

FEATURE DESCRIPTION The Samsung eNB supports a combination of TDD 20 MHz CC and FDD 3 MHz CC in downlink. TDD-FDD CA only supports Inter-band Non-contiguous CA. Figure below depicts the 20 + 3 aggregated LTE channels.

For detailed description of CA functionality and its operational procedures, refer to LTE-SW5500: CA Call Control feature. The eNB shall not perform the following configuration for the UE RRCConnected to TDD cell (pre-Rel.12 CA):

SCell addition with FDD Scell. Measurement configuration for SCell addition: Event A4 measurement.

SYSTEM OPERATION This section describes how to configure the feature in Samsung system and provides associated key parameters, counters, and KPIs. Refer to the System Operation section of LTE-SW5500: CA Call Control feature for configuration, key parameter, and detailed information on counters associated with this feature


50


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.912 „Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)‟


51


LTE-ME5110, FDD Carrier Aggregation (5 + 5) INTRODUCTION The FDD Carrier Aggregation (5 + 5) feature enables an eNB to aggregate with 5 + 5 MHz LTE Component Carriers (CCs). The purpose of multiple CCs aggregation is to have wider channel bandwidth, which helps operators to increase bitrates for end-users.

BENEFIT With this feature, an operator can combine individual CCs from different band and bandwidths. This ensures that all the spectrum resources are utilized effectively across the network for improving efficiency and achieving higher peak throughputs.

DEPENDENCY 










Others oOthers: The UE needs to support this feature.

LIMITATION Due to UE availability of CA with 4 × 4MIMO, CA with 2 × 2MIMO can be supported.



52



FEATURE DESCRIPTION The Samsung eNB supports a combination of 5 + 5 MHz CCs in downlink. Each aggregated carriers is referred to as CC. Figure below depicts the 5 + 5 aggregated LTE channels.

You can have the following three types of carrier allocation based on the spectrum usage:



Intra-band Contiguous CA



Intra-band Non-contiguous CA



Inter-band Non-contiguous CA

For detailed description of CA functionality and its operational procedures, refer to LTE-SW5500: CA Call Control feature description document.


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

53


[3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.912 „Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)‟


54




DEPENDENCY 











LIMITATION Due to UE availability of CA with 4 × 4MIMO, CA with 2 × 2 MIMO can be supported.



55



FEATURE DESCRIPTION The Samsung eNB supports a combination of 3 + 5 MHz CCs in downlink. Each aggregated carriers is referred to as CC. Figure below depicts the 3 + 5 aggregated LTE channels.

You can have the following three types of carrier allocation based on the spectrum usage:



Intra-band Contiguous CA



Intra-band Non-contiguous CA



Inter-band Non-contiguous CA



REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

56


[3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.912 „Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)‟


57




DEPENDENCY 

HW dependency oOthers: CA can be restricted depending on the HW configuration.










LIMITATION Due to UE availability of CA with 4 × 4MIMO, CA with 2 × 2MIMO can be supported.



58



FEATURE DESCRIPTION For inter-band non-contiguous CA, the Samsung eNB supports a combination of 3 + 3 MHz CCs in downlink. Each aggregated carrier is referred to as CC. Figure below depicts the 3 + 3 aggregated LTE channels.



REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟


59


[5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.912 „Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)‟


60


LTE-ME6003, Smart FeICIC INTRODUCTION Heterogeneous network, also known as HetNet, is an efficient way to meet the rapidly increasing demand of data traffic. In HetNet, pico cells are used due to its advantageous aspects of performance improvement in hot spot region and relatively low cost compared to macro cells. By deploying pico cells in highly crowded spots inside macro coverage, a portion of user traffic of macro cells is expected to be offloaded. Then offloaded users will enjoy plenty of resources of pico cells, thus the throughput performance of those users can be highly improved. At the same time, remaining users in macro cells will take advantage of the additional amount of available resources which was originally occupied by offloaded users. These aspects can be interpreted as a sort of cell splitting gain. That is, HetNet has good potential of improving user throughput by distributing the traffic burden to macro and pico cells. However, pico cells have a fundamental disadvantage in terms of transmission power. Usually, macro cells have several ten-fold amount of transmit power compared to pico. This imbalance between macro and pico makes it difficult to offload macro traffic into pico. In other words, a limited number of users with considerably good channel quality from pico is able to overcome superior transmit power of macro, and only those users takes the benefit of resources of pico cells. Therefore, the expected cell splitting gain of HetNet is definitely limited. FeICIC, also known as Non-CA based ICIC (LTE-ME4003), provides an effective way to increase the number of users offloaded to pico cells. Rigorously speaking, FeICIC intentionally makes macro users take handover to adjacent pico cells even with the weakness of pico transmit power. This operation is called cell range expansion or CRE. Since CRE leads to deteriorating performance of those offloaded users due to the server interference from macro cells, FeICIC also provides the time-domain interference coordination from macro to pico. Macro is forced to minimize the transmit power in some portion of subframes, which are called Almost Blank Subframe (ABS). By applying ABS, it is possible to protect users attached to pico from strong interference from macro cells. Even though FeICIC provides load balancing gain and interference coordination, there must be more chance to improve performance because FeICIC supports only the one-way interference coordination from macro to pico. As the number of pico cells increases, the interference from adjacent pico cells begins to degrade the performance of network. Moreover, the effects of interference from adjacent cells are dynamically changing according to user mobility or data traffic conditions. However, FeICIC is only able to adapt the ABS pattern in semi-statically.


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DL Smart (LTE-ME6004) combined with FeICIC, which is called Smart FeICIC, is designed to fully utilize the potential gain of HetNet. Smart FeICIC not only provides the CRE functionality for load balancing, but also provides the two-way interference coordination functionality between any adjacent cells in a centralized manner.

BENEFIT Smart FeICIC takes the benefits from Smart Scheduler and FeICIC at the same time.

Edge UE throughput enhancement by means of interference coordination. Macro-to-pico offloading by means of cell range expansion. While FeICIC provides the semi-static one-way interference control from macro to pico, Smart FeICIC further provides the dynamic two-way interference control from: oMacro to macro (and vice-versa) oMacro to pico (and vice-versa) oPico to pico (and vice-versa)

DEPENDENCY 

HW dependency oOthers: Smartscheduler Server



Required Network Elements oSmart Scheduler






Interface & Protocols oX2 interface, proprietary interface between the eNB and Smartscheduler.



Prerequisite Features oLTE-ME4003 FeICIC



Others oThis feature is available only for interference coordination between the macro and pico cells.

LIMITATION 

Obtainable benefits depend on UE capability. All UEs including legacy UEs (which do not support eICIC/FeICIC) take the benefit of interference coordination.

eICIC UEs take the benefit of CRE as well. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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FeICIC UEs take both the benefit of CRE and that of CRS-IC as well.

SYSTEM IMPACT Performance and Capacity This feature enhances the system capacity together with FeICIC. Interface This feature uses a proprietary interface between the eNB and Smartscheduler.

FEATURE DESCRIPTION Smart FeICIC is a combination of DL Smart (LTE-ME6004) and Non-CA Based ICIC (LTE-ME4003). Both DL Smart and Non-CA Based ICIC are time-domain interference coordination features. Smart FeICIC not only resolves the issues from a collision between the dynamic muting pattern (of DL Smart) and the ABS pattern (of Non-CA Based ICIC), but also defines the scheduling constraints both for dynamic muted subframes and ABS. Additional interfaces between Smart Scheduler (server) and eNBs are designed. Table below outlines the functional behaviors of Non-CA Based ICIC, DL Smart, and Smart FeICIC features. Functionality

Non-CA Based ICIC

DL Smart

Smart FeICIC

(LTE-ME4003)

(LTE-ME6004)

(LTE-ME6003)

CRE

O

X

O

ABS (macro  pico)

O

X

O

Dynamic interference coordination (macro ↔ macro)

X

O

O

Dynamic interference coordination (macro ↔ pico)

X

O

O

Dynamic interference coordination (pico ↔ pico)

X

O

O

Samsung proprietary interface between the Smart Scheduler and eNBs is exploited, as well as 3GPP standard interfaces. The macro eNB sends the ABS pattern information, which is semi-statically determined by macro itself taking into account load information from pico cells. Based on the ABS pattern information, the smart scheduler finally determines the dynamic muting pattern, which is applied to eNB schedulers in real time, as depicted in figure below.


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As depicted in figure below, since the dynamic muting pattern is delivered to all cells in HetNet, ABS of a macro cell can be used to protect all the users who are interfered by the corresponding macro cell, while ABS was only helpful to pico users in FeICIC. In addition, the Smart Scheduler controls interference problem in subframes except ABS, so that all subframes are under controlling interference in any time if needed. As a result, it is also possible to improve the performance of users located even in highly densified area.

Smart FeICIC can be deployed in both of the following two possible configurations:


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C-RAN: In this configuration, all macro and pico are deployed in form of high and low power radio units and they are connected to a centralized bank eNB via optical fiber, and Smart Scheduler is deployed in the bank eNB. This structure enables real-time feedback, dynamic scheduling and interference coordination. In

D-RAN: In this configuration, DUs in macro and pico cells are connected to Smart Scheduler via Ethernet. Even though D-RAN experiences backhaul delay of IP network, Smart Scheduler can jointly control the scheduling of macro and pico cells considering interference issues. In both forms of C-RAN and D-RAN, Smart FeICIC can control interference from all possible interfering sources in HetNet.


How to Activate This section provides the information that you need to configure the feature Preconditions Smart FeICIC is a combination of DL Smart (LTE-ME6004) and Non-CA Based ICIC (LTE-ME4003) features. Activation Procedure To activate this feature, do the following:



Run CHG-CELLSCHR-CONF, and set SmartCellCoordinationEnable to ON.



FeICIC operates by establishing eICIC partnership among a macro cell and pico cells in the macro cell coverage. To activate the FeICIC feature between eICIC partners: oRun CHG-CELLSCHR-CONF and set EICIC_FLAG to True.



eICIC partnership starts when the macro cell‟s E-UTRAN Cell Global Identifier (ECGI) is entered as the pico cell EICIC_FLAG is set to True. If the macro cell‟s EICIC_FLAG is set to True and the number of the connected partner pico cells is smaller than the maximum number of pico cell partners, eICIC partnership can be established. To configure the maximum number of the pico cell partners that can be established by one macro cell, do the following: oRun CHG-DL-EICIC and set MAX_NUM_OF_PARTNER.

Deactivation Procedure To deactivate this feature, do the following:



Run CHG-CELLSCHR-CONF, and set SmartCellCoordinationEnable to OFF.


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Run CHG-DL-EICIC and set EICIC_FLAG of any of the eICIC partners to False.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CELLSCHR-CONF/RTRV-CELLSCHR-CONF Parameter

Description

CellId

The cell number. This value must not exceed the maximum number of cells supported by the system.

SmartCellCoordinationEnable

It is the SmartCell DL Coordination function On(true)/Off(false) flag, i.e. control flag of interworking function between eNB and the Smart Scheduler Server.

Parameter Description of CHG-CELLSCHR-CONF/RTRV-CELLSCHR-CONF Parameter

Description

EICIC_FLAG

This parameter is ON/OFF value of eICIC function.

Parameter Description of CHG-DL-EICIC/RTRV-DL-EICIC Parameter

Description

CRE_FLAG

This parameter is ON/OFF value of CRE function. This parameter can be individually switched, but in order for CRE function to operate, EICIC_FLAG needs to be set to "True" in both macro cell and its pico partner cell.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-DL-EICIC/RTRV-DL-EICIC Parameter

Description

MAX_CRE_CIO_CHANGE_ WAIT

This parameter specifies the number of times that satisfies CRE Offloading decision continuously.

THR_CRE_OFFLOAD

This parameter specifies the threshold (Macro/Pico) for offloading. For macroto-pico offloading, macro load should be higher than THR_CRE_OFFLOAD, and the partner pico load should be lower than THR_CRE_OFFLOAD_PARTNER. For pico-to-macro offloading, pico load should be higher than THR_CRE_OFFLOAD, and the partner macro load should be lower than THR_CRE_OFFLOAD_PARTNER.

THR_CRE_OFFLOAD_PART NER

This parameter specifies the threshold (Macro/Pico) for offloading. For macroto-pico offloading, macro load should be higher than THR_CRE_OFFLOAD, and the partner pico load should be lower than THR_CRE_OFFLOAD_PARTNER. For pico-to-macro offloading, pico load should be higher than THR_CRE_OFFLOAD, and the partner macro load


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Description should be lower than THR_CRE_OFFLOAD_PARTNER.

EICIC_BOUNDARY

Specify the maximum CIO value for eICIC UE.

FEICIC_BOUNDARY

Specify the maximum CIO value for FeICIC UE.

MAX_NUM_OF_PARTNER

The maximum the number of Pico Cells which can be made a partnership in one macro cell.

T_CRE_STATUS_UPDATE

This parameter is the term for CRE status update.

THR_CRE_ACT_MACRO

Threshold for CRE activation. For activating CRE, the Macro cell load should be above the threshold.

THR_CRE_ACT_PICO

Threshold for CRE activation. For activating CRE, the pico cell load should be lower than the threshold.

THR_CRE_UE_RATIO

Threshold for CRE activation. For activating CRE, the ratio of CRE UEs in the macro cell should be larger than the threshold.

THR_CRE_DEACT_ABS_FU LL

Threshold for CRE deactivation. For deactivating CRE, ABS Full should be lower than this parameter value to be CRE deactivation. (macro cell dedicated parameter) * ABS Full = Number of RBs usage for Pico CRE UEs / Number of RBs usage for Macro UEs + Number of RBs usage for UEs of all Pico partners

Parameter Descriptions of CHG-SONFN-ENB/RTRV-SONFN-ENB Parameter

Description

cellOffLoadThreshold

This is a threshold parameter for triggering cell off. A cell load is lower than this threshold for triggering cell off.

cellActLoadThreshold

This is a threshold parameter for activating cell on. It is lower than this threshold for triggering cell off. When a cell load is bigger than this threshold, the cell activates NBR dormant cells.

cellOffReliability

This parameter is a condition for reliability that shall be satisfied in cell off decision. A ratio of sum of bin counts shall excess this value for cell off.

cellActReliability

This parameter is a condition for reliability that shall be satisfied in cell activation decision. A ratio of sum of bin counts shall excess this value for cell activation.

PARTNER_MCC

This parameter is Mobile Country Code (MCC) of partner cell, which should be set for the partnership.

PARTNER_MNC

This parameter is Mobile Network Code (MNC) of partner cell, which should be set for the partnership.

PARTNER_CELL_IDENTITY

This parameter is Macro Cell Identity of partner cell, which should be established for the partnership.

T_PARTNERSHIP_GUARD

This parameter specifies the waiting time (s) to resume the partnership establishment request, in case of the specified number of consecutive failures.

T_PARTNERSHIP_RETRY

This parameter specifies the interval (ms) between two consecutive partnership establishment requests, in case of failure with the former request.

PARTNERSHIP_TX_COUNT

This parameter specified the maximum number of consecutive partnership establishment requests, in case of failure with the former request.

EICIC_SINR_ESTIMATE_EN ABLE

This parameter configures SINR estimation function based on periodic MR for legacy UE, when eICIC function is activated


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Counters and KPIs Table below outlines the main counters associated with this feature. Display Name

Type Name

Type Description

ODHO_X2_OUT

OnDemandHoOutAtt

This type is counted by sending X2 handover request with Switch off ongoing cause

OnDemandHoOutSucc

This type is counted by receiving UE context release command triggered by On-demand handover in Source eNB

OnDemandHoInAtt

This type is counted by receiving X2 handover request with Switch off ongoing cause

OnDemandHoInSucc

This type is counted by sending UE context release command triggered by On-demand handover from Source eNB

OnDemandHoOutAtt

Counted when the cause of S1 HO Request transmission is Miscellaneous::O&M Intervention.

OnDemandHoOutSucc

Counted if the UE performs OnDemand Hobased HO when the Source eNB successfully receives UE Context Release Request message.

OnDemandHoOutAttToUT RAN

Counted when the cause of UTRAN HO Request transmission through S1 is Miscellaneous::O&M Intervention.

OnDemandHoOutSuccTo UTRAN

Counted if the UE performs OnDemand Hobased HO when the Source eNB successfully receives UE Context Release Request message.

OnDemandHoInAtt

Counted when the cause of HO Request reception through S1 is Miscellaneous::O&M Intervention.

OnDemandHoInSucc

Counted if the UE performs OnDemand Hobased HO when the target eNB successfully sends HO Notify message.

OnDemandHoIntraOutAtt

Counted when the eNB attempts Intra HO out caused by OnDemand forced HO.

OnDemandHoIntraOutSuc c

Counted if the UE performs OnDemand forced HO when the Source eNB successfully successes Intra HO out.

OnDemandHoIntraInAtt

Counted when the eNB receives a request of Intra Hand-In caused by OnDemand forced HO.

OnDemandHoIntraInSucc

Counted if the UE performs OnDemand Hobased HO when the target eNB successfully Hand-in.

RedirectionToLTEByOnDe mandHo

This type is counted by conducting redirection to LTE (On-demand handover)

RedirectionToWCDMAByO nDemandHo

This type is counted by conducting redirection to WCDMA (On-demand handover)

RedirectionToGERANByO nDemandHo

This type is counted by conducting redirection to GERAN (On-demand handover)

RedirectionToHRPDByOn DemandHo

This type is counted by conducting redirection to HRPD (On-demand handover)

ODHO_X2_IN

ODHO_S1_OUT

ODHO_S1_IN

ODHO_INTRA_OUT

ODHO_INTRA_IN

ODHO_REDIRECTION


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Chapter 1 Air Performance Enhancement Display Name

ODHO_TIMER_RELEASE

Type Name

Type Description

CcoToGERANByOnDema ndHo

This type is counted by conducting CCO to GERAN (On-demand handover)

ReleaseCntByTimer

Forced released UE by timer expiration

REFERENCE None


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LTE-ME6004, DL Smart INTRODUCTION The DL-Smart feature performs centralized coordination for the radio resource of all cells connected to Smart Scheduler server to enhance the cell performance. In this case, each eNB allocates the physical radio resource to the UE based on the results of the coordination.

BENEFIT This feature enhances the performance of DL data transmission.

DEPENDENCY 

Required Network Elements: oThe Smart Scheduler server supports C-RAN only or D-RAN only. oThe eNB operates RT or NRT mode depending on the mode of Smart Scheduler server.

LIMITATION 

The number of cells supporting a Smart Scheduler server is different according to the type of the server.



This feature needs time synchronization between cells.



This feature requires backhaul latency between the eNB and Smart Scheduler server less than 30 ms (in round-trip-time (RTT)) for D-RAN.

SYSTEM IMPACT Interdependencies between Features For Smart Scheduler, DL Smart (LTE-ME6004) performs the basic function of Smart Scheduler related to the coordination information exchange between eNBs and Smart Scheduler. Performance and Capacity This feature increases the cell edge throughput for user in cell edge area. For the detailed information on the counters and KPIs, refer to the System Operation section of this feature. Coverage This feature performs interference mitigation for cell edge area among neighboring cells. Thus, the cell coverage can be increased with this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Interfaces The Smart signalling messages are introduced for interference mitigation of neighboring cells, which requires the proprietary interface between eNBs and Smart Scheduler.

FEATURE DESCRIPTION The network for DL-Smart is consisted of one Smart Scheduler and a large number of eNBs. Samsung supports two types of DL-Smart networks as C-RAN and DRAN. Figure below depicts the network diagram of C-RAN.

The C-RAN eNB is concentrated with Smart Scheduler, so C-RAN network guarantees short transmission delay. Each RU distributed from C-RAN eNB is connected with DU using the dark fiber. Figure below depicts the network diagram of D-RAN.


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The D-RAN eNB is distributed from Smart Scheduler using Ethernet network connection with long transmission delay (30 ms in RTT). Each eNB is connected with Smart Scheduler server and is classified as C-RAN eNB or D-RAN eNB according to the transmission delay between Smart Scheduler server and eNB. In each of the network architecture, if there is no Smart Scheduler, then eNBs can provide stand-alone operation. The software structure of Smart Scheduler network is depicted in figure below.

Each SW block performs the following functions:

Coordinator in Smart Scheduler server oNon real time (NRT) coordination oReal time (RT) coordination for C-RAN cells oTransfer NRT/RT resource allocation pattern to RT-Scheduler

Pre-Scheduler in Smart Scheduler server oSelection of the representative UE for each cell oTransfer the metric of the representative UE to coordinator.

UE Manager in Smart Scheduler server oSRS/MR based Tx power estimation of Cell oGeneration of the preferred resource allocation pattern

RT-Scheduler in eNB


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oSelects the candidate UE, and then transfer channel and traffic information of the candidate UE to Smart Scheduler server. When carrier aggregation and DL Smart are enabled at the same time, RTScheduler receives MR for the SCell from each UE and then transfers it to Smart Scheduler Server periodically. oAllocates resource using NRT/RT resource allocation pattern The scheduling procedure of this feature is as follows:

1 The RT-Scheduler block of the eNB selects the candidate UE for each cell. 2 The UE Manager block of the Smart Scheduler generates the preferred resource allocation pattern for each UE using DL/UL received power estimation.

3 The Pre-Scheduler block selects the representative UE for each cell. 4 The Coordinator block performs the coordination of radio resources for each cell based on the scheduling metric, generates the resource allocation pattern based on the coordination results and sends it to the eNB.

5 The RT-Scheduler block compensates the UE channel quality (CQI) based on the resource allocation pattern and allocates the control channel and the data channel to the UE.

6 The RT-Scheduler block confirms the resource allocation based on the resource coordination information from Post-Scheduler block and generates RLC/Modem control information.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure To activate this feature, do the following:



Run CHG-SRS-IDLE, and then set SMART_SRS_ENABLE to TRUE.



Run CHG-CELLSCHR-CONF, and then set SMART_CELL_COORDI_ENABLE to ON.




Run CHG-SRS-IDLE, and then set SMART_SRS_ENABLE to FALSE.



Run CHG-CELLSCHR-CONF, and then set SMART_CELL_COORDI_ENABLE to OFF.


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Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SRS-IDLE/RTRV-SRS-IDLE Parameter

Description

SMART_SRS_ENABLE

This parameter indicates whether or not SRS configuration is enabled for Smart Scheduling

Parameter Descriptions of CHG-CELLSCHR-CONF/RTRV-CELLSCHR-CONF Parameter

Description

CELL_ID


SMART_CELL_COORDI_ENABLE

This parameter is the control flag of interworking function between eNB and the Smart Scheduler.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameters Descriptions of CHG-SCHR-IDLE Parameter

Description

EARFCN_DL

This parameter is the DL EARFCN supported Smart Scheduler.

Counters and KPIs Table below outlines the main counters associated with this feature. Family Name

Type

Description

Throughput distribution counter for CS ON OFF (1 of 2)

ThroughputAvg

Average UE throughput

ThroughputTot

Total UE throughput

ThroughputCnt

Total number of UE throughputs

Thru0_20

Number of UE throughputs ranging from 0kbps to 20kbps

Thru16880_16900

Number of UE throughputs ranging from 16,880kbps to 16,900kbps

...

...

Thru16900_16920

Number of UE throughputs ranging from 16,900kbps to 16,920kbps

...

...

Thru280600_306200

Number of UE throughputs ranging from 280,600kbps to 306,200kbp

Throughput distribution counter for CS ON OFF (2 of 2)


74


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.819 „Coordinated multi-point operation for LTE physical layer aspects‟ [9] 3GPP TR 36.913 „Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN)‟


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LTE-ME6005, UL Smart (Interference Coordination for UL) INTRODUCTION This feature performs centralized coordination for the radio resource of all cells to enhance the cell performance. In this case, each eNB allocates the physical radio resource to the UE based on the results of the coordination.

BENEFIT This feature enhances the performance of UL data transmission.

DEPENDENCY 

Required Network Elements oSmart Scheduler Smart Scheduler server that supports C-RAN only or DRAN only



Prerequisite Features oLTE-ME6004 (DL Smart)

LIMITATION 

The number of cells supported by a Smart Scheduler server is different according to the type of the server.



This function needs time synchronization.



This feature follows DL Smart (LTE-ME6004) feature in terms of the network architecture, interfaces, and so on.

SYSTEM IMPACT Interdependencies between Features Interdependent Feature: LTE-ME6004, DL Smart The LTE-ME6004 feature performs the basic function for the Smart Scheduler related to the coordination information exchange between eNBs and Smart Scheduler. Based on the LTE-ME6004 feature, the UL Smart (LTE-ME6005) feature performs interference mitigation for UL data transmission in cell edge area.


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Performance and Capacity This feature increases the cell edge throughput for user in cell edge area. For detail information on the counters and KPIs, refer to the System Operation section of this feature. Coverage This feature performs interference mitigation for cell edge area among neighboring cells, and thereby increases the cell coverage. Interfaces The smart signaling messages are introduced for interference mitigation of neighboring cells, which requires the proprietary interface between eNBs and Smart Scheduler.

FEATURE DESCRIPTION The UL-Smart network consists of one Smart Scheduler and a large number of eNBs. Samsung supports two types of UL-Smart networks as C-RAN and D-RAN. Figure below depicts the network diagram of C-RAN.

The C-RAN eNB is concentrated with Smart Scheduler, so C-RAN network guarantees short transmission delay less than 1ms. Each RU distributed from CRAN eNB is connected with DU using the dark fiber. Figure below depicts the network diagram of D-RAN.


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D-RAN eNB is distributed from Smart Scheduler using Ethernet network connection with transmission delay longer than 1ms. Each eNB is connected with Smart Scheduler server and is classified as C-RAN eNB and D-RAN eNB according to the transmission delay between Smart Scheduler server and eNB. In each of the network architecture, if there is no Smart Scheduler, then eNBs can provide stand-alone operation. Figure below depicts the software structure of Smart Scheduler network.

Each SW block performs the following functions:

Coordinator in Smart Scheduler server oDetermines inter-interference relation between serving cell and neighbor cells based on SRS. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oGenerates allocation pattern using load information and inter-cell interference relation to improve the performance of cell edge UE. oTransfers resource allocation pattern to RT-Scheduler.

UE Manager in Smart Scheduler server oDetermines (1) cell edge UEs based on SRS oDetermines (2) which of cells receive inter-cell interference from UE of the serving cell based on SRS. oTransfers UE information (1) and (2) to RT-Scheduler, and information (2) to Coordinator.

RT-Scheduler in eNB oTransfers load information, such as the amount of inter-cell interference, which UEs generate in the serving and amount of inter-cell interference that the serving cell receives from neighbor cells, to Coordinator. oAllocates resource using UE information and resource allocation pattern. The scheduling procedure of this feature is as follows:

1 The RT-Scheduler block calculates the amount of inter-cell interference, which UEs generate in the serving and amount of inter-cell interference that the serving cell receives from neighbor cells. Then RT-Scheduler transfers them to Coordinator in Smart Scheduler server.

2 The UE manager determines (1) cell edge UE and (2) which of cell receive intercell interference from UE of serving cell based on SRS. Then UE manager transfers UE information (1) and (2) to RT-Scheduler, and information (2) to Coordinator.

3 The coordinator determines inter-interference relation between cells based on SRS. Then coordinator generates allocation pattern using load information and inter-cell interference relation.

4 The coordinator transfers resource allocation pattern to RT-Scheduler. 5 The RT-Scheduler block allocates resource to UEs using UE information and resource allocation pattern for cell edge UEs to avoid inter-cell interference from neighbor cells.


How to Activate Preconditions The smart server should be supported.


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Activation Procedure To activate this feature, run CHG-SMTUL-SCHED, and set the value of ulSmartCsOnOff to 1, 2, or 3. The recommended value of ulSmartCsOnOff is 3. Deactivation Procedure To deactivate this feature, run CHG-SMTUL-SCHED, and set the value of ulSmartCsOnOff to 0.

Key Parameters Run RTRV-SMTUL-SCHED to retrieve the configuration information of smart uplink scheduling. Activation/Deactivation Parameters Parameter

Description

dbIndex

This is just db index.

ulSmartCsOnOff

This parameter enables or disables the coordinated scheduling (CS) of UL smart. If ulSmartCsOnOff = 0, coordinated scheduling is off (false). If ulSmartCsOnOff = 1, coordinated scheduling using start RB index is on (true). RT-Scheduler can allocate the resource from the lowest RB index or from the highest RB index for cell edge UE to avoid inter-cell interference between neighbor cells. If ulSmartCsOnOff = 2, coordinated scheduling using edge pattern is on (true). RT-Scheduler allocates the resource using edge pattern for cell edge UE to avoid inter-cell interference between neighbor cells. If ulSmartCsOnOff = 3, coordinated scheduling using start RB index and edge pattern is on (true). RT-Scheduler dynamically switches between CS using start RB index and CS using edge pattern.

Configuration Parameters There are no specific configuration parameters.


REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.819 „Coordinated multi-point operation for LTE physical layer aspects‟ [9] 3GPP TR 36.913 „Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN)‟


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LTE-ME6009, Inter Cluster Smart Scheduler INTRODUCTION Smart LTE system improves the cell throughput performance with a new proprietary network structure element called as Smart Scheduler server. A cluster of cells is connected to the server and interference coordination for these multiple cells is performed in a centralized manner. Each Smart Scheduler has a limitation induced by its H/W capacity, which can just cover the restricted number of cells. Consequently, this causes boundary areas between clusters. To eliminate this inherent vulnerability, an Inter Cluster Smart Scheduler server is newly introduced to support interference coordination in the boundary areas between clusters.

BENEFIT This feature improves the performance of DL and UL data transmissions among clusters served by Smart Scheduler servers.

DEPENDENCY 

Required Network Elements oSmart Scheduler: This feature works with Smart Scheduler and Inter Cluster Smart Scheduler servers.



Prerequisite Features oLTE-ME6004 (DL Smart)

LIMITATION 

The number of cells supported by an Inter-cluster Smart Scheduler is different depending on the type of Inter-cluster Smart Scheduler server.



This feature needs time synchronization between cells.



This feature requires backhaul latency between Smart Scheduler server and Inter-cluster Smart Scheduler server less than a pre-defined threshold in roundtrip-time (RTT).



This feature can be used only when the DL Smart (LTE-ME6004) feature is enabled.

SYSTEM IMPACT Interdependencies between Features Interdependent Feature: LTE-ME6004, DL Smart eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The LTE-ME6004 feature performs the basic function for the Smart Scheduler related to the coordination information exchange between eNBs and smart scheduler. Based on the LTE-ME6004 feature, the Inter-Cluster Smart Scheduler (LTE-ME6009) feature performs interference mitigation among clusters coordinated by Smart Schedulers. Performance and Capacity This feature increases the cell edge throughput for user in cell edge area. For detail information on the counters and KPIs, refer to the System Operation section of this feature. Coverage This feature performs interference mitigation for cell edge area among neighboring cells, and thereby increases the cell. Interfaces The smart signaling messages are introduced for interference mitigation of neighboring cells, which requires the proprietary interfaces between eNBs and Smart Scheduler, and between Smart Schedulers and Inter-Cluster Smart Scheduler.

FEATURE DESCRIPTION The architecture of Inter-Cluster Smart Scheduler is depicted in figure below. When Smart Schedulers are deployed without Inter-Cluster Smart Scheduler, each Smart Scheduler server forms a cluster, which consists of hundreds of cells or more number of cells depending on Smart Scheduler‟s HW capacity. Since each Smart Scheduler operates independently from others, interference cannot be handled between cells belonging to different clusters. However, when Inter-Cluster Smart Scheduler is added, interference coordination can be supported among multiple clusters. Inter-Cluster Smart Scheduler can fully coordinate thousands of cells or more number of cells depending on server‟s HW capacity.

To support Inter-Cluster Smart Scheduler, the roles of Inter-Cluster Smart Scheduler and Smart Scheduler are defined as follows:

Inter-Cluster Smart Scheduler eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oUpper-level coordinator of Smart Schedulers. oFully coordinates the entire constituent cells.

Smart Schedulers oPerforms scheduling and SRS processing for each cell individually. oActivate local coordination automatically only when failure occurs in a communication to Inter-Cluster Smart Scheduler. To support Inter-Cluster Smart Scheduler, interference measurements are shared between different clusters. In figure below, the UE is located in the cluster boundary area. The neighboring cells 1 and 2, belonging to the neighbor cluster, measure the SRS transmitted by the UE. Then the two cells send the SRS measurements to Smart Scheduler A. Based on the SRS measurements, Smart Scheduler A can estimate the interference of cells 1 and 2 to the UE. eNBs in cluster boundary area are automatically connected to neighboring Smart Scheduler.

In addition, coordination results are shared between different clusters. In figure below, Smart Scheduler A sends the coordination results of cells 1 and 2 to the cells in cluster-boundary area. Based on that, those cells can perform link adaptation depending on whether the cells 1 and 2 are muted or not.


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How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure To activate this feature, do the followings:



Run CHG-UPSCHR-INF for Inter Cluster Smart Scheduler, and set SCHR_IPv4 SCHR_IPv6 to the IP address of Inter Cluster Smart Scheduler.



Run CHG-SCHR-INF for Smart Scheduler, and then set UPPER_SCHR_IPv4 or UPEER_SCHR_IPv6 to the IP address of Inter Cluster Smart Scheduler to which Smart Scheduler is connected to.



Run CHG-SCHR-INF for Smart Scheduler, and then set UPPER_SCHR_STATE to SchrUnlocked.

To activate Inter-Cluster uplink Smart Scheduling in this feature, do the followings:



Run CHG-UPSMTUL-CONF for Inter Cluster Smart Scheduler, and then set UL_SUPER_SMART_CS_ON_OFF to be 1 (On status).




Run CHG-SCHR-INF for Smart Scheduler, and then set upperSchrState to SchrLocked.


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To deactivate Inter-Cluster uplink Smart Scheduling in this feature, do the followings:



Run CHG-UPSMTUL-CONF for Inter Cluster Smart Scheduler, and then set UL_SUPER_SMART_CS_ON_OFF to be 0 (Off status).

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-UPSCHR-INF/RTRV-UPSCHR-INF Parameter

Description

IP_VER

This parameter is the IP version of Inter Cluster Smart Scheduler.

SCHR_IPv4

This parameter is the IPv4 address of Inter Cluster Smart Scheduler.

SCHR_IPv6

This parameter is the IPv6 address of Inter Cluster Smart Scheduler.

SECONDARY_IPv4

This parameter is the secondary IPv4 address of Inter Cluster Smart Scheduler.

SECONDARY_IPv6

This parameter is the secondary IPv6 address of Inter Cluster Smart Scheduler.

Parameter Descriptions of CHG-SCHR-INF/RTRV-SCHR-INF Parameter

Description

UPPER_SCHR_STATE

This parameter is the administrative state of Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler) internetworking function.

SCHR_IPv4

This parameter is the IPv4 address of Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler).

SCHR_IPv6

This parameter is the IPv6 address of Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler).

SECONDARY_IPv4

This parameter is the secondary IPv4 address of Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler).

SECONDARY_IPv6

This parameter is the secondary IPv6 address of Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler).

Parameter Descriptions of CHG-UPSMTUL-CONF/RTRV-UPSMTUL-CONF Parameter

Description

UL_SUPER_SMART_CS_O N_OFF

This parameter is the control flag (ON/OFF status) of uplink Upper-level Smart Scheduler (that is, Inter Cluster Smart Scheduler).

Configuration Parameters There are no specific configuration parameters for this feature.

Counters and KPIs Table below outlines the main counters associated with this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 1 Air Performance Enhancement Family Name

Type

Description

Inter Cluster Smart Scheduler Traffic

InterClusterSchrTrafRxTh ruAvg

The calculated number that indicates the average per-second size of all received packets from Smart Scheduler during the collection interval.

InterClusterSchrTrafRxBy teTot

The overall calculated size of all packets received from Smart Scheduler during the collection interval.

InterClusterSchrTrafRxBy teCnt

The cumulated count to collect InterClusterSchrTrafRxByte

InterClusterSchrTrafTxTh ruAvg

The calculated number that indicates the average per-second size of all transmitted packets to Smart Scheduler during the collection interval.

InterClusterSchrTrafTxBy teTot

The overall calculated size of all packets transmitted to Smart Scheduler during the collection interval.

InterClusterSchrTrafTxBy teCnt

The cumulated count to collect InterClusterSchrTrafTxByte

InterClusterSchrPktDelay Avg

The average one-way delay between Inter Cluster Smart Scheduler and Smart Scheduler.

InterClusterSchrPktDelay

The overall cumulated number of InterClusterSchrDelay between Inter Cluster Smart Scheduler and Smart Scheduler.

InterClusterSchrPktCount

The overall cumulated number of transmitted packets between Inter Cluster Smart Scheduler and Smart Scheduler.

Inter Cluster Smart Scheduler Delay

REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.211 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation‟ [3] 3GPP TS 36.212 „Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding‟ [4] 3GPP TS 36.213 „Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures‟ [5] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [6] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟ [7] 3GPP TR 36.814 „Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects‟ [8] 3GPP TR 36.819 „Coordinated multi-point operation for LTE physical layer aspects‟ [9] 3GPP TR 36.913 „Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN)‟


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LTE-ME6017, Smart CRS-IC INTRODUCTION Cell-specific Reference Signals (CRS) are transmitted by an eNB in every subframe and in every resource block. Power boosting is also allowed for CRS transmission. CRS transmission causes interference to UEs in neighboring cells. In 3GPP Rel-11, a UE can cancel CRS interference from neighboring cells by using some assistance information sent by its serving cell. Interference Cancellation (IC) improves DL performance by increasing DL throughput.

BENEFIT DL performance is improved because the UE can cancel CRS interference from neighboring cells.

DEPENDENCY 

Required Network Elements oSmart Scheduler: DL smart scheduler is required.



Interface & Protocols oThe UE should be able to receive Rel-11 CRS assistance information (TS 36.331).

Prerequisite Features oLTE-ME6004 DL Smart

LIMITATION None

SYSTEM IMPACT Performance and Capacity With this feature, the serving cell can send some assistance information to celledge UEs, which can cancel CRS interference from neighboring cells. So, improvement in cell-edge performance is expected by using this feature. Since CRS-IC is performed by UEs, it is not possible for eNB to directly measure performance enhancement due to CRS-IC. Still, existing statistics for DL CQI distribution, DL MCS distribution, DL MAC air throughput, and so on can be used to measure the performance of this feature.


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FEATURE DESCRIPTION CRS are transmitted by eNB in every subframe and in every resource block. Power boosting is also allowed for CRS transmission. CRS transmission causes interference to UEs in neighboring cells. In 3GPP Rel-11, a UE can cancel CRS interference from neighboring cells by using some assistance information sent by its serving cell. Figure below depicts the CRS interference.

To cancel CRS interference from a neighboring cell, the UE needs to know the physical Cell ID (PCID), the number of CRS antenna ports (1, 2, or 4) and the MBSFN subframe configuration of that cell. The eNB provides this assistance information to all UEs, which indicate that they can receive this information (FGI 115 bit = 1). The eNB can collect the assistance information using X2 interface. However, Samsung's implementation method is based on DL smart scheduler and does not use X2 interface. For each cell, the eNB creates a cell-specific list of interfering cells. DL smart scheduler receives this list from several eNBs and returns to the eNBs, a UE-specific list for each UE, which is capable of receiving assistance information. The eNB sends UE-specific assistance information using RRC CONNECTION RECONFIGURATION message. In this message, the information is contained in NeighCellsCRS-Info-r11 IE (inside RadioResourceConfigDedicated IE). For each UE, the assistance information consists of a list of maximum 8 cells. The assistance information IE of CRS interference cancellation is as follows (from TS 36.331):


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The UE can use the assistance information to cancel the CRS interference from neighboring cells. Figure below depicts the CRS interference cancellation.


How to Activate This section provides the information that you need to configure the feature. Preconditions DL smart scheduler is required. Activation Procedure To activate this feature, do the following:

Run CHG-CELLSCHR-CONF, and set smartCellCoordiEnable and smartCrsicEnable to True.

Key Parameters Activation Parameters RTRV-CELLSCHR-CONF/CHG-CELLSCHR-CONF Parameter

Description

smartCrsicEnable

It is the Smart CRS-IC function On (true)/Off (false) flag.

REFERENCE [1] 3GPP TS 36.300: E-UTRA and E-UTRAN; Overall description; Stage 2 [2] 3GPP TS 36.331: Radio Resource Control (RRC); Protocol specification [3] 3GPP TS 36.306: User Equipment (UE) radio access capabilities [4] 3GPP TS 36.213: Physical layer procedures


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Chapter 2

Call Control

LTE-SW0100, Support UE Category 0 INTRODUCTION The Samsung eNB supports UE category 0 (Cat 0), which is a low complexity UE, and has reduced Tx and Rx capabilities compared to other UE categories. The Cat 0 UEs can access a cell only if the SIB1 message indicates that access of these UEs is supported. Otherwise, the Cat 0 UEs consider the cell as barred.

BENEFIT Operators can offer IoT services. This feature reduces terminal modem complexity compared to category 1 UEs. This feature controls eNB overload traffic by barring the delay tolerant devices such as Cat 0 UE.

DEPENDENCY The Cat 0 MTC device is required. (with Rel-12 compliant)

LIMITATION The paging period of Cat 0 UE should be set larger than 40 ms for type B halfduplex FDD mode.

SYSTEM IMPACT Interface between eNB and MME needs to be updated based on Rel-12 to support this feature.

FEATURE DESCRIPTION LTE Cat 0 is low cost devices such as Machine-Type Communications (MTC). Its characteristic is 1RX Antenna operation, type B half-duplex FDD mode and reduced Transport Block Size (TBS). These Devices can receive or send a maximum 1000 bits of unicast traffic per subframe which results in peak data rates to 1 Mbps in DL and UL. Due to this, within one TTI, a UE indicating Cat 0 can receive up to:

1000 bits for a transport block associated with C-RNTI/P-RNTI/SI-RNTI/RARNTI

2216 bits for another transport block associated with P-RNTI/SI-RNTI/RA-RNTI eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 2 Call Control

The Cat 0 UE supports TDD, FD-FDD and type B HD-FDD. The Type B HD-FDD UE can not receive both first and last DL subframes (following/preceding UL subframes). Therefore, the Cat 0 UEs should be removed from the candidate list for scheduling the TTI. To allow access to Cat 0 devices, the eNB indicates its support of Cat 0 UE through the SIB1 message, as depicted in figure below.

The Cat 0 UE sends RRCConnectionRequest or RRCConnectionEstablishment message with a new LCID value as listed table below from TS 36.321 specification. The eNB recognizes the UE as Cat 0 when it receives LCD value as 01011. The LCD field size is 5 bits. Index

LCID values

00000

CCCH (Other Category UEs)

00001-01010

Identity of the logical channel

01011

CCCH (Cat 0 UE)

The Cat 0 UEs can support a maximum TBS of 1000 bits for unicast traffic and 2216 bits for broadcast traffic. Therefore, the eNB supports resource allocation with the consideration of 1000 bits for unicast traffic. UE also indicates Cat 0 capability to eNB in UE CapabilityInformation. The UERadioPagingInfo IE contains information used for paging of Cat 0 UEs. The UE includes this field when the Cat 0 has been indicated by ue-Category-v12xy in UE-EUTRA-CAPABILITY as depicted in figure below.


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The eNB forwards the UERadioPaging Information to MME. The MME replaces the UE capability information, if stored previously, with the latest information. It returns the updated information to the eNB in the paging message. The eNB uses this paging IE to apply specific paging schemes. Paging period for Cat 0 UE should be set larger than 40 ms for HD-FDD mode. In TS 36.304, the nB can be {4T, 2T, T, T/2, T/4, T/8, T/16, T/32}. To configure the nB as {T/4, T/8, T/16, T/32}, set the paging period larger than 40 ms. For TDD and FD-FDD mode, the paging period is same as other normal UEs.

Modified Cat 0 Signalling Details.


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How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-CELL-INFO and set CATEGORY0_ALLOWED to True. Deactivation Procedure Run CHG-CELL-INFO and set CATEGORY0_ALLOWED to False.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameter To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CELL-INFO/RTRV-CELL-INFO Parameter

Description

CATEGORY0_ALLOWED

This parameter indicates whether the cell allows access for Category 0 UEs. False: An operating cell does not allow category 0 UE access. True: An operating cell allows category 0 UE access.

Configuration Parameter There are no specific parameters associated with this feature.


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2. Release 12. [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification. Release 12.


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[3] 3GPP TS36.306 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio access capabilities. Release 12. [4] 3GPP TR36.888 Study on provision of low-cost Machine Type Communications(MTC) User Equipments (UEs) based on LTE. Release 12. [5] 3GPP TS23.401 General Packet Radio Service enhancements for Evolved Universal Terrestrial Radio Access Network. Release 12. [6] 3GPP TS36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification. Release 12.


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LTE-SW0101, Support for UE Category 1, 2, 3, and 4 INTRODUCTION The Support for UE Category 1, 2, 3, and 4 feature allows an eNB to support UE Category 1, 2, 3, and 4, which are defined in 3GPP TS36.306. Different UE categories define different UE capability in terms on throughput.

BENEFIT The eNB supports different device types that are capable of DL 2 × 2 MIMO, 2RX diversity, or SISO.

The UE can improve downlink throughput if it supports DL 2 × 2 MIMO.

DEPENDENCY Related Radio Technology E-UTRAN (LTE)

Others Commercial UE terminal per each UE category is required

LIMITATION None

SYSTEM IMPACT The implementation of this feature does not have any impact on the network.

FEATURE DESCRIPTION Samsung eNB has no limitation on supporting UE category 1, 2, 3, and 4, which have up to two layers downlink and do not support uplink 64 QAM. UE Category 1 supports SISO and UE Category 2, 3, and 4 supports 2 × 2 MIMO. Table below outlines modulation and MIMO format supported for each UE categories. Category Modulation

1

2

Downlink

QPSK, 16 QAM, 64 QAM

Uplink

QPSK, 16 QAM


3

4

5 QPSK, 16 QAM, 96

Chapter 2 Call Control Category MIMO

1

2

3

4

5 64 QAM

2Rx diversity

Assumed in performance requirements across all LTE UE categories

2 × 2 MIMO

Not supported

4 × 4 MIMO

Not supported

Mandatory Mandatory

Table below outlines DL throughput and the number of downlink layers per UE Category, which are defined in 3GPP TS36.306 release 9 version. The maximum total bits per Transmission Time Interval (TTI) in the downlink defines the maximum downlink throughput. A single TTI corresponds to the 1ms subframe duration. The maximum downlink throughput specified for the release 8 and 9 versions of the 3GPP specifications is 300 Mbps. This is supported when transferring 2 transport blocks per subframe on a single RF carrier. UE Category

Maximum number of DL-SCH transport block bits received within a TTI

Maximum number of bits of a DL-SCH transport block received within a TTI

Total number of soft channel bits

Maximum number of supported layers for spatial multiplexing in DL

Category 1

10296

10296

250368

1

Category 2

51024

51024

1237248

2

Category 3

102048

75376

1237248

2

Category 4

150752

75376

1827072

2

Category 5

299552

149776

3667200

4

Table below outlines UL throughput and 64 QAM support per UE Category, which are defined in 3GPP TS36.306 release 9 version. Similarly, the maximum total bits per TTI in the uplink defines the maximum uplink throughput. The maximum uplink throughput specified for the release 8 and 9 versions of the 3GPP specifications is 75Mbps. This is supported when transferring 1 transport block per subframe on a single RF carrier. UE Category

Maximum number of bits of an UL-SCH transport block transmitted within a TTI

Support for

Category 1

5160

No

Category 2

25456

No

Category 3

51024

No

Category 4

51024

No

Category 5

75376

Yes

64 QAM in UL

Figure below depicts the UE capability information message flow for signaling UE category (or categories).


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How to Activate This feature runs automatically, and it cannot be disabled.

Key Parameters There are no specific parameters associated with this feature.

Counters and KPIs Table below outlines the main counters associated with this feature. Family Display Name

Type Name

Type Description

UE Category

UE_Category_1

Number of UEs in the UE Category 1

UE_Category_2


UE_Category_3


UE_Category_4


UE_Category_5


UE_Category_6


UE_Category_7



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Chapter 2 Call Control Family Display Name

Type Name

Type Description

UE_Category_8


UE_Category_9


UE_Category_10


UE_Category_11


UE_Category_12


UE_Category_13


UE_Category_14


UE_Category_15


UE_Category_0


REFERENCE [1] 3GPP TS36.306 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio access capabilities [2] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) Protocol specification


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LTE-SW0111, UE Counting per Category INTRODUCTION The eNB performs counting for each category of RRC_Connected UE and collects the statistics per eNB.

BENEFIT UE counting per category helps to analyze connected UEs' status per category.

DEPENDENCY AND LIMITATION Limitation This statistics collection is impossible if the eNB cannot acquire UE category information from the MME during idle to active transition.

If a time-out occurs because the UE does not transmit ATTACH COMPLETE, the statistics is counted but the UE context release may be performed in the MME.

FEATURE DESCRIPTION This feature enables the operator to know the number of UE in the network for each UE category. The eNB obtains the UE category information during two possible states-during attachment or during idle to active transition.

The figure below shows during ATTACH procedure: eNB saves UE category during UE Capability Enquiry/UE Capability Information procedure and counts the statistics after ATTACH procedure is finished.


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The figure below shows duringIdle to Active procedure: eNB saves UE category during Initial Context Setup Request/Initial Context Setup Response procedure and counts the statistics after ATTACH is finished.

SYSTEM OPERATION How to Activate Execute the command CHG-UEPWRSAVING-CONF to set 'usedFlag' to 'USE'. Operator can disable this feature by setting the parameter to 'NO_USE'. Key Parameters This feature is basically enabled and operator cannot disable. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Counters and KPIs Family Display Name

Type Name

Type Description

UE Category

UE_Category_1


UE_Category_2


UE_Category_3


UE_Category_4


UE_Category_5


UE_Category_6


UE_Category_7


UE_Category_8


UE_Category_9


UE_Category_10


UE_Category_11


UE_Category_12


UE_Category_13


UE_Category_14


UE_Category_15


UE_Category_0


REFERENCE [1] The Vendor‟s LTE solution shall support functionality to enquire UE capability and record number of UEs per eNodeB and per cell for each UE category. [2] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [3] 3GPP TS36.306 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio access capabilities (Release 9) [4] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification (Release 9)


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LTE-SW0114, Enhancements for Diverse Data Applications INTRODUCTION Multiple Diverse Data Applications like Instant Messaging, Interactive Content Pull, Gaming, HTTP Video Streaming are used in UE such as Smart Phones. With the increasing use of such applications, UE suffers from low battery life time. So, it is necessary to optimize the power consumption of UE. So, eNodeB is required to provide a better power efficient mode of operation.

BENEFIT Reduction in Power Consumption. Improvements in System efficiency.

DEPENDENCY AND LIMITATION Dependency Release 11 UE to support UEAssistance Information.

During transmitting UEAssistance message to UE, if UE sets powerPrefIndication to normal, UE starts or restart timer T340 with the value of powerPrefIndicationTimer received from eNB during RRCconnectionReconfiguration message.

UE should not change the PowerPreferenceMode from Normal to lowPowerConsumption until the T340 timer expires.

UE upon initiating RRCConnectionreestablishment procedure, releases powerPrefIndicationConfig, if configured and stop timer T340, if running;

FEATURE DESCRIPTION The purpose of RAN Enhancements to Diverse Data Applications is for eNodeB to provide UE a power saving operation. Upon configuring the UE to provide power preference indications, eNodeB waits for UE to provide its power saving preference. Once the Preference is known from UE, eNodeB provides appropriate resolution based on operator's configuration. This feature is enabled based on the Device Type of the UE. If the UE DeviceType is set to noBenFromBatConsumpOpt received from UE in UE-EUTRACapability-v920-IE. Then this feature is disabled as no DRX solution could be provided since UE does not wants a Network Controlled Battery Saving Solution. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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If the UE DeviceType is not set to noBenFromBatConsumpOpt received from UE in UE-EUTRA-Capability-v920-IE, then this feature is enabled.

1 If this feature is enabled, eNodeB configures UE to provide power preference indication by sending RRC connection reconfiguration message to UE with powerPrefIndicationConfig data structure set to setup. This configuration message can be sent during any reconfiguration on the serving cell or in the reconfiguration message during handover to E-UTRA. powerPrefIndicationConfig-r11 is present in otherConfig-r9 structure. The setup parameter part of the powerPrefIndicationConfig contains powerPrefIndicationTimer-r11 parameter which is a Prohibit timer for Power Preference Indication reporting of UE. This prevents from frequent PowerMode Change (T340 timer) of the UE from Normal to Low.

2 UE responds with RRC connection reconfiguration complete message. 3 UE further notifies eNodeB with its power saving preference by sending UEAssistanceInformation message to eNodeB with setting either of two possible values

apowerPrefIndication is set to lowPowerConsumption (or) bpowerPrefIndication is set to normal. UE start or restart timer T340 with the timer value set to the powerPrefIndicationTimer received from eNB during RRCconnectionReconfiguration message. UE should not change the PowerPreferenceMode from Normal to lowPowerConsumption until the T340 timer expires. UE upon initiating RRCConnectionreestablishment procedure, UE should release powerPrefIndicationConfig, if configured and stop timer T340, if running.

4 When eNodeB receives the message with parameter powerPrefIndication: oIf eNodeB receives the message with parameter powerPrefIndication set to lowpowerconsumption, then based on the Operator configuration, eNodeB may respond to UE with either a long value for long DRX cycle or Feature/Parameter

Configuration

Value/Description

DRX

Long cycle length

80, 160, 320, 640, 1280, 2560 ms

eNodeB may respond to UE with RRC connection release message to save UE device power consumption. oIf eNodeB receives the message with parameter powerPrefIndication set to normal, then normal operation resumes.


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SYSTEM OPERATION How to Activate Execute the command CHG-UEPWRSAVING-CONF to set 'usedFlag' to 'USE'. Operator can disable this feature by setting the parameter to 'NO_USE'. Key Parameters CHG-UEPWRSAVING-CONF/RTRV-UEPWRSAVING-CONF Parameter

Description

USED_FLAG

This parameter shows whether the UE power saving function is supported or not.

PREF_IND_TIMER

This parameter shows Prohibit timer(T340) for Power Preference Indication reporting. Value in seconds. Value s0 means prohibit timer is set to 0 second or not set, value s0dot5 means prohibit timer is set to 0.5 second, value s1 means prohibit timer is set to 1 second and so on

SUPPORT_METHOD

This parameter shows the way to support UE power saving.

CHG-UEPWRSAVING-DRXINFO/RTRV-UEPWRSAVING-DRXINFO Parameter

Description

QCI

This parameter is the QoS Class Identifier (QCI). The range is 0-255.The standard QCI defined in the standard document is 1-9. 0 and 10-255 can be used by the operator optionally.

DRX_CONFIG_SETUP

This parameter indicates whether to use the DRX for UE power saving. Release: DRX is not used. Setup: DRX profile is used

ON_DURATION_TIMER

This parameter is onDurationTimer to monitor PDCCH in DRX mode. (onDurationTimer-Specifies the number of consecutive PDCCH-subframe(s) at the beginning of a DRX Cycle.)


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Chapter 2 Call Control Parameter

Description

DRX_INACTIVITY_TIMER

This parameter is drxInactivityTimer to monitor PDCCH in DRX mode. (drxInactivityTimer-Specifies the number of consecutive PDCCH-subframe(s) after successfully decoding a PDCCH indicating an initial UL or DL user data transmission for this UE.)

DRX_RETRANSMISSION_TI This parameter is drxRetransmissionTimer to monitor PDCCH in DRX mode. MER (drx-RetransmissionTimer-Specifies the maximum number of consecutive PDCCH-subframe(s) for as soon as a DL retransmission is expected by the UE.) LONG_DRXCYCLE_START_ The long DRX cycle and drx start offset values to run onDurationTimer in DRX OFFSET_TYPE mode. For UE power saving, longDRCCycle can have multiples of sf80.

Counters and KPIs There are no related counters or KPIs.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2. Release 11. [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); RRC Control and Signalling.Release 11. [3] 3GPP TR 36.822 LTE Radio Access Network (RAN) enhancements for diverse data applications (Release 11)


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LTE-SW0315, Extended Access Barring (SIB14) INTRODUCTION The Extended Access Barring (EAB) restricts low priority UEs, such as MachineType Communications (MTC), from accessing the network during RAN or Core Network overload state. UEs configured for EAB are considered more tolerant to access restrictions than other UEs. To support this feature, barring information is included in the SIB14 message, which is broadcasted to UEs.

BENEFIT This feature controls RAN and Core Network (CN) overload conditions by restricting access attempts from UEs that are configured for EAB.

DEPENDENCY Prerequisite Features Feature ID (Feature Name): None

Others Requires Release 11 UE.

LIMITATION None

SYSTEM IMPACT Interfaces Air interface

A new RRC SystemInformationBlockType14 message. A new eab-ParamModification-r11 IE in RRC Paging message.

FEATURE DESCRIPTION Due to the diverse applications and services deployed in the LTE network, there can be excess traffic. This excess traffic can overload RAN or Core Network. During excess traffic, the eNB reaches congestion state when;

The CPU load level of eNB exceeds overload threshold.


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Accepted UEs have reached its full capacity such as maximum number of UEs per cell except the reserved resources.

All the MMEs connected to the eNB inform the eNB about the congestion state through sending OVERLOAD START message to the eNB. Figure below depicts the procedures performed by the eNB to apply EAB when the eNB is overloaded or the CN is overloaded. When the congestion state has reached or by manual configuration by the operator, the eNB applies EAB. The eNB broadcasts the access class bitmap and the UE category through the SIB14 message to UEs. The UE determines whether it is subjected to barring based on this information. If the UE in idle state determines that it is subjected to barring, it refrains from sending a connection request.

EAB Evaluation The UE acquires the SIB14 message upon receiving a PAGING message from the eNB, or if it has not stored a valid version of SIB14 upon entering into the RRC_IDLE state. The eNB sets the SIB14 Flag as TRUE when sending the SIB1 message. The UE access is denied if all of these conditions are met, as depicted in figure below:


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The UE belongs to Access Class (0 to 9). The UE category is the same as received in SIB14. The UE access class is the same as received in SIB14.

The eNB removes the EAB through the SIB14 message specifying as Not Barred when it comes back to normal state or receives the OVERLOAD STOP message from the MME.


How to Activate This section provides the information that you need to configure the feature. Preconditions Ensure that the following conditions are met before enabling this feature:

The SIB14_PERIOD of CHG-SIB-INF must be set to 0~6. Activation Procedure Run CHG-EAB-PARA and set EAB_PARAM_USAGE to 1. Deactivation Procedure Run CHG-EAB-PARA and set EAB_PARAM_USAGE to 0.


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Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-EAB-PARA/RTRV-EAB-PARA Parameter

Description

EAB_PARAM_USAGE

This parameter is the usage flag of eab barring status.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-EUTRA-A6CNF/RTRV-EUTRA-A6CNF Parameter

Description

CELL_NUM

This parameter is the number of cells. This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity provided to the carrier per system is 1 FA/3 Sector, up to 3 cells are supported.

eabBarringStatusType

This parameter is the eab barring status to be changed or retrieved for All MME overload status or manual. eabBarManual: Manual Mode eabBarAuto: All MME overload status

eabPlmnType

This parameter is the eab barring status to be changed or retrieved for each plmn or all plmns. eabPlmn0: eab barring status for PLMN #0. eabPlmn1: eab barring status for PLMN #1. eabPlmn2: eab barring status for PLMN #2. eabPlmn3: eab barring status for PLMN #3. eabPlmn4: eab barring status for PLMN #4. eabPlmn5: eab barring status for PLMN #5. eabCommon: eab barring status for all PLMNs.

eabParamUsage

This parameter is the usage flag of eab barring status.

eabCategory

Indicates the category of UEs for which EAB applies. categoryA: corresponds to all UEs. categoryB: corresponds to the UEs that are neither in their HPLMN nor in a PLMN that is equivalent to it. categoryC: corresponds to the UEs that are neither in the PLMN listed as most preferred PLMN of the country where the UEs are roaming in the operator-defined PLMN selector list on the USIM, nor in their HPLMN nor in a PLMN that is equivalent to their HPLMN.

accessClass[10]

This parameter indicates whether access class is barred or not barred. Index 0 to 9 correspond to access class 0 to 9. barred: access class x barred. (x: 0~9) not barred: access class x not barred. (x: 0~9)


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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2. Release 11. [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification. Release 11. [3] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access (E-UTRA); S1 Application Protocol (S1AP). Release 11. [4] 3GPP TS22.368 Service requirements for Machine-Type Communications (MTC). Release 11. [5] 3GPP TS23.401 General Packet Radio Service enhancements for Evolved Universal Terrestrial Radio Access Network. Release 11.


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LTE-SW0318, SIB Broadcast (SIB16) INTRODUCTION In case of eMBMS operations, services are made available via broadcast from the BM-SC to the UE and an alignment in time between the two end-to-end nodes is necessary to ensure correct operations and service quality. For live services supported by DASH, the segments are generated on the fly at the encoder and they are continuously published and made accessible by assigning a unique URL to each segment. Segment availability times are used to signal to clients the availability time of segments at the specified HTTP-URLs. These times are provided in Universal Time (UTC), aka wall-clock time and clients typically compare the wall-clock time to segment availability times before accessing the segments at the specified HTTP-URLs. If the time is not accurate, the DASH client may fetch earlier which segment is not available yet. Or if DASH client fetches it late, the delay will be increased. Therefore, the timing accuracy at the UE side for eMBMS operations can be greatly enhanced through use of the UTC time in the SIB 16 system message. SIB 16 contains information related to GPS time and UTC time.

BENEFIT This feature will mitigate the DASH time drift problem caused by time difference between UE and BM-SC.

DEPENDENCY AND LIMITATION Dependency Broadcast SIB16 in the cells where provide eMBMS service. Limitation Only Release 11 UE can receive the system messages.

FEATURE DESCRIPTION SystemInformationBlockType16 contains information related to GPS time and Coordinated Universal Time (UTC). The UE may use the parameters provided in this system information block to obtain the UTC, the GPS and the local time. The relationship between UTC and GPS time is as follows:

timeInfoUTC = GPS time-leapSeconds, where timeInfoUTC counts up by 10 ms and leapSeconds counts by second. -- ASN1START SystemInformationBlockType16-r11 ::= SEQUENCE { timeInfo-r11 SEQUENCE {


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timeInfoUTC-r11 dayLightSavingTime-r11 leapSeconds-r11 localTimeOffset-r11 } lateNonCriticalExtension ...

INTEGER (0..549755813887), BIT STRING (SIZE (2)) OPTIONAL, INTEGER (-127..128) OPTIONAL, INTEGER (-63..64) OPTIONAL OPTIONAL, OCTET STRING OPTIONAL,

------

Need Need Need Need Need

OR OR OR OR OP

} -- ASN1STOP

SystemInformationBlockType16 field descriptions dayLightSavingTime: It indicates if and how daylight saving time (DST) is applied to obtain the local time. The semantics is the same as the semantics of the Daylight Saving Time IE in TS 24.301 [35] and TS 24.008 [49]. The first/leftmost bit of the bit string contains the b2 of octet 3, i.e. the value part of the Daylight Saving Time IE, and the second bit of the bit string contains b1 of octet 3.

leapSeconds: Number of leap seconds offset between GPS Time and UTC. UTC and GPS time are related i.e. GPS time -leapSeconds = UTC time.

localTimeOffset: Offset between UTC and local time in units of 15 minutes. Actual value = IE value * 15 minutes. Local time of the day is calculated as UTC time + localTimeOffset.

timeInfoUTC: Coordinated Universal Time corresponding to the SFN boundary at or immediately after the ending boundary of the SI-window in which SystemInformationBlockType16 is transmitted. The field indicates the integer count of 10 ms units since 00:00:00 on 1 January, 1900. This field is excluded when estimating changes in system information, i.e. changes of timeInfoUTC should neither result in system information change notifications nor in a modification of systemInfoValueTag in SIB1.

SYSTEM OPERATION How to Activate In order to change activation, operator has to set the Parameters (sib 16) in the RTRV-SIB-INF command.

Key Parameters RTRV-SIB-INF/CHG-SIB-INF Parameter

Description

CELL_NUM

This parameter is the number of cells.This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity provided to the carrier per system is 1 FA/3 Sector, up to 3 cells are supported.

sib16Period

This parameter is the broadcast interval for SIB 16. not_used: Does not broadcast SIB16.


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REFERENCE N/A


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LTE-SW0320, RRC Connection Management INTRODUCTION The RRC Connection Management feature establishes the layer 3 connection between a UE and an eNB so the UE can access the LTE network. The feature manages the layer 3 connection, including establishment, reconfiguration, and release of the connection.

BENEFIT Operator can provide radio connectivity to its subscribers within LTE network. LTE users can have a radio connection with an eNB for LTE service.

DEPENDENCY None

LIMITATION None


FEATURE DESCRIPTION RRC connection management involves following RRC procedures:

RRC connection establishment: This procedure is used to establish an RRC connection between the UE and eNB.

RRC connection reconfiguration: This procedure is used to set up, modify, or delete the radio configuration of the RRC connection.

RRC connection release: This procedure is used to release the RRC connection. RRC connection re-establishment: This procedure is used to re-establish the RRC connection between the UE and eNB.

RRC Connection Establishment The eNB performs the RRC connection establishment procedure upon the UE‟s request. The RRC connection establishment procedure is used for RRC connection setup, and the eNB establishes signaling connection with the UE through this eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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procedure. When receiving the RRC connection request from the UE, the eNB considers the current RRC connection configuration status to determine whether RRC connection can be established. If it is possible, it allocates resources for SRB1 and sends them to the UE with the RRC Connection Setup message. The UE responds to this message. When receiving the RRC Connection Setup Complete message, it completes the RRC connection establishment procedure and then performs subsequent procedures. Figure below depicts the RRC connection establishment procedure.

The UE performs the random access procedure with the eNB.

1 The UE transmits the RRC Connection Request message to the eNB. UE transmits the message from the Physical Channel PUSCH/Transport Channel UL-SCH/Logical Channel CCCH using SRB0 in TM Mode.

2 The eNB determines whether RRC connection can be established. If RRC connection can be established, the eNB transmit the RRC Connection Setup message to the UE. Information required for SRB1 setup is included in this message. The eNB responds to UE with the message from the Physical Channel PDSCH/Transport Channel DL-SCH/Logical Channel CCCH using SRB0 in TM Mode. If RRC connection cannot be established, the eNB transmit the RRC Connection Reject message to the UE.

3 After setting up SRB1 according to the RRC Connection Setup message received from the eNB, the UE responds with the RRC Connection Setup Complete message. The UE responds to the eNB with the message from the Physical Channel PUSCH/Transport Channel UL-SCH/Logical Channel DCCH using SRB1 in AM Mode. The NAS message: Attach Request (ESM: PDN Connectivity Request) is included in this message.

4 The eNB transmits the Initial UE message including the NAS message: Attach Request (ESM: PDN Connectivity Request) received from the UE to the MME. A procedure to be followed depends on the MME‟s operation.

RRC Connection Reconfiguration eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The eNB performs the RRC connection reconfiguration procedure to set up/change/release the radio configuration for controlling the connected UE. The RRC connection reconfiguration procedure is used in various situations to set up the call, to add the DRB, to change the radio resource configuration, to change the measurement configuration, to change the security context, and so on. Figure below depicts the RRC Connection Reconfiguration procedure. (E-RAB setup case)

The eNB receives E-RAB Setup Request from the MME. The QoS information of the E-RAB(s) to be added, an NAS message to be sent to the UE and ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST are included in the E-RAB Setup Request.

1 When receiving the E-RAB Setup Request from the MME, the eNB determines whether new E-RAB(s) can be added. If it is possible, it reallocates internal resources and transmits the RRC Connection Reconfiguration to the UE.

2 The UE sets up the additional DRB(s) specified by the RRC Connection Reconfiguration and responds to the eNB with the RRC Connection Reconfiguration Complete. The eNB responds with the RRC Connection Reconfiguration message from the Physical Channel PDSCH/Transport Channel DL-SCH/Logical Channel DCCH using SRB1 in RLC AM Mode. oNAS: Attach Request oNAS: Activate Default EPS Bearer Context Request. UE responds with the RRC Connection Reconfiguration Complete message from the Physical Channel PUSCH/Transport Channel UL-SCH/Logical Channel UL DCCH using SRB1 in RLC AM Mode. oNAS: Attach Complete oNAS: Activate Default EPS Bearer Context Accept.

3 The eNB responds to the MME with the E-RAB Setup response. The E-RAB Setup response includes setup success/failure results for each E-RAB.

RRC Connection Release The eNB performs RRC connection release procedures to release a call of the connected UE, to redirect, or to process the CSFB. When releasing the RRC connection with the UE, the eNB transmits the RRC Connection Release message to the UE. Then, the eNB releases the entire UE context. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Figure below depicts the RRC Connection Release prcedure is as follows.

1 In case of eNB initiated UE context release procedure, the eNB transmits UE Context Release request to the MME to request for call release. (for example. Inactivity timer expired)

2 The MME transmits UE Context Release command to the eNB for S1 release. 3 The eNB transmits RRC Connection Release to the UE. 4 After performing the RRC Connection Release procedure with the UE, the eNB responds to the MME with UE Context Release Complete. RRC Connection is released when its inactivity timer expires. For UEs in RRC_CONNECTED mode, the eNB monitors both signlaing inactivity time and user data inactivity time, and it triggers RRC Connection Release procedures when both inactivity timers are expired. Signaling inactivity timer and user data inactivity timer are configurable respectively. RRC Connection is released when eNB detects a failure of the S1 connection. The S1 connection failure occurs when the eNB cannot communicate with the MME of the UE for a certain time period or when the eNB does not receive an ECHO Response message for the SGW of the UE for a certain time period. When eNB detects a failure in the connection with MME or SGW, the eNB releases all the UEs that have S1 connection with the MME or the SGW.

RRC Connection Reestablishment The eNB performs the RRC connection reestablishment procedure upon the UE‟s request to re-setup the RRC connection. This procedure is triggered upon detecting Radio Link Failure (RLF), handover failure, mobility from E-UTRA failure, integrity check failure from lower layers and upon RRC Connection Reconfiguration failure. The RRC connection reestablishment procedureIt helps to re-establish the SRB1 operation and re-activate the Security Algorithms. (Security Algorithms are not changed). This procedure is successful when eNB has a valid UE Context. If eNB does not have a UE context, then UE moves to RRC_IDLE_STATE. Figure below depicts the RRC connection reestablishment procedure.


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The UE performs the Random access procedure with the eNB for RRC connection reestablishment.

1 The UE transmits the RRC Connection Reestablishment Request message to the eNB.

2 The eNB checks whether the UE has the UE context. If it has the UE context, the eNB transmits the RRC Connection Reestablishment message to the UE. The information required for SRB1 setup and AS security context restoration is included in this message. If RRC connection re-establishment is not possible, the eNB transmit the RRC Connection Reestablishment Reject message to the UE.

3 The UE restores the SRB1 setup and AS security context according to the RRC Connection Reestablishment message received from the eNB and responds with the RRC Connection Reestablishment Complete message.

4 The eNB performs the RRC connection reconfiguration procedure with the UE to set up the SRB2 and DRB. If the handover procedure was being performed, it processes subsequent procedures with the EPC. Radio Link Failure (RLF) The reason for RLF

PUCCH release: If PUCCH release occurs 40 times in a row, PUCCH release is turned on in DSP and transmitted to call control block through OutOfSync message.

PUSCH HARQ residual error: If PUSCH HARQ residual error occurs 40 times in a row, PUSCH HARQ residual error is turned on in DSP through OutOfSync message and transmitted to call control block. See the Reference 36.300, T1, T2. Call Summary Log (CSL) related RLF If Sync with an UE is released in DSP block, the DSP notifies OutOfSync to call control block. Later if call control block is notified of InSync (HARQACK/NACK is received 20 times) again from DSP block or receives RRC Connection Re-establishment Request from UE, RFT operates normally. But if RRC Connection Re-establishment Request is not received, call is released after a eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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certain period of time (for example: 5 seconds).



Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There are no specific parameters associated with this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-TIMER-INF/RTRV-TIMER-INF Parameter

Description

RRC_CONNECTION_SET UP

The time to wait for reception of the RrcConnectionSetupComplete message after sending the RrcConnectionSetup message from the eNB to the UE.

RRC_CONNECTION_REC ONFIG

The time to wait for reception of the RrcConnectionRecofigurationComplete message after sending the RrcConnectionRecofig message from the eNB to the UE.

RRC_CONNECTION_RE_ ESTABLISH

The time to wait for reception of the RrcConnectionReestablishmentComplete message after sending the RrcConnectionReestablishment message from the eNB to the UE.

INTERNAL_RRC_RESET

The time to wait for multiple UEs to be released after sending the RrcConnectionRelease to the UEs at eNB reset.

INTERNAL_SOLICIT_MEA SUREMENT_REP ORT

The time to wait for reception of the Measurement Report message from the UE according to the Solicit Measurement Report procedure.

RRC_SECURITY_MODE_ COMMAND

The time to wait for reception of the SecurityModeComplete message after sending the SecurityModeCommand message from the eNB to the UE.

RRC_UE_CAPABILITY_E NQUIRY

The time to wait for reception of the UeCapabilityInformation message after sending the UeCapabilityEnquiry message from the eNB to the UE.

RRC_CONNECTION_REL EASE

The time to wait for reception of the message from the PDCB block confirming that the RrcConnectionRelease message was successfully sent after sending it from the eNB to the UE.

RRC_HANDOVER_PREP ARATION

The time to wait for reception of the RrcUL-HandoverPreparationTransfer message after sending the RrcHandoverFromEU-TRAPreparationRequest message from the eNB to the UE.

RRC_UE_INFORMATION _REQUEST

The time to wait for reception of the InformationResponse message after sending the InformationRequest message from the eNB to the UE.


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Parameter Descriptions of CHG-PLMNSIGTIMER-INFO/RTRVPLMNSIGTIMER-INFO Parameter

Description

INTERNAL_SIGNALING_INA CTIVITY_TIMER

This parameter is the inactivity timer information for a signaling message. An eNB starts an inactivity timer for a signaling message after a UE is attached. Signaling Inactivity is (re)initialized if a signaling message containing NAS PDU information is received from a UE or MME.

Parameter Descriptions of CHG-INACT-INTER/RTRV-INACT-TIMER Parameter

Description

INTERNAL_USER_INACTIVIT Y

This parameter is the User inactivity timer value. User Inactivity is (re)initialized if UL/DL data is received from a UE or MME.

Counters and KPIs Table below outlines the main counters associated with this feature. Display Name

Type Name

Type Description

RRC_ESTAB

ConnEstabAtt

RRC CONNECTION REQUEST count

ConnEstabSucc

RRC CONNECTION SETUP COMPLETE count

ConnEstabFail_CP_CC_TO

RRC connection Establishment fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP)

ConnEstabFail_CP_CC_FAIL

RRC connection Establishment fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block

ConnEstabFail_UP_MAC_FAI L

RRC connection Establishment fails due to the failure in the MAC block

ConnEstabFail_UP_PDCP_FA IL

RRC connection Establishment fails due to the failure in the PDCP block

ConnEstabFail_UP_RLC_FAIL

RRC connection Establishment fails due to the failure in the RLC block

ConnEstabFail_RRC_SIG_TO

RRC connection Establishment fails due to RRC signaling timeout (not received)

ConnEstabFail_S1AP_LINK_F AIL

RRC connection Establishment fails due to the S1 SCTP link failure

ConnEstabFail_S1AP_SIG_FA IL

RRC connection Establishment fails due to receiving S1AP signaling

ConnEstabReject_CP_CC_FAI L

A call is rejected due to cell status (e.g. barred) or MME status (e.g. no available MMEs) during the RRC connection establishment

ConnEstabReject_CP_CAPA_ CAC_FAIL

A call is rejected due to CAC during the RRC connection establishment

ConnEstabReject_S1AP_MME _OVLD

A call is rejected due to MME overload during the RRC connection establishment


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Chapter 2 Call Control Display Name

Type Name

Type Description

RRC_RECONFIG

ConnReconfigAtt

RRC CONNECTION RECONFIGURATION count

ConnReconfigSucc

RRC CONNECTION RECONFIGURATION COMPLETE count

ConnReEstabAtt

RRC CONNECTION REESTABLISHMENT REQUEST count

ConnReEstabSucc

RRC CONNECTION REESTABLISHMENT COMPLETE count

ConnReEstabFail_CP_CC_FA IL

RRC connection Re-establishment fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block

ConnReEstabFail_UP_MAC_F AIL

RRC connection Re-establishment fails due to the failure in the MAC block

ConnReEstabFail_UP_PDCP_ FAIL

RRC connection Re-establishment fails due to the failure in the PDCP block

ConnReEstabFail_UP_RLC_F AIL

RRC connection Re-establishment fails due to the failure in the RLC block

ConnReEstabFail_RRC_SIG_ TO

RRC connection Re-establishment fails due to RRC signaling timeout (not received)

ConnReEstabFail_S1AP_LINK _FAIL

RRC connection Re-establishment fails due to the S1 SCTP link failure

ConnReEstabFail_S1AP_SIG_ FAIL

RRC connection Re-establishment fails due to receiving S1AP signaling

ConnReEstabReject_CP_CC_ FAIL

A call is rejected due to cell status (e.g. barred) or MME status (e.g. no available MMEs) during the RRC connection reestablishment

ConnReEstabReject_CP_CAP A_CAC_FAIL

A call is rejected due to Capacity based CAC during the RRC connection reestablishment

ConnReEstabReject_CP_QOS _CAC_FAIL

A call is rejected due to Air QoS based CAC during the RRC connection reestablishment

ConnRelease_CP_CC_NORM AL

Normal release

ConnRelease_CP_CC_TO

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP)

ConnRelease_CP_CC_FAIL

A call is released due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block

ConnRelease_UP_GTP_FAIL

A call is released due to the failure in the GTP block

ConnRelease_UP_MAC_FAIL

A call is released due to the failure in the MAC block

ConnRelease_UP_MAC_UE_I NACT

A call is released due to user inactivity

ConnRelease_UP_PDCP_FAI L

A call is released due to the failure in the PDCP block

RRC_REESTAB

RRC_RELEASE


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RRC_CONN

Type Name

Type Description

ConnRelease_UP_RLC_FAIL

A call is released due to the failure in the RLC block

ConnRelease_RRC_HC_TO

A call is released due to HO preparation timeout (not received HO command)

ConnRelease_RRC_SIG_FAIL

A call is released due to receiving RRC signaling

ConnRelease_RRC_SIG_TO

A call is released due to RRC signaling timeout (not received)

ConnRelease_CP_BH_CAC_F AIL

A call is released due to Backhaul QoS based CAC

ConnRelease_CP_CAPA_CA C_FAIL

A call is released due to Capacity based CAC

ConnRelease_CP_QOS_CAC _FAIL

A call is released due to Air QoS based CAC

ConnRelease_S1AP_CU_FAIL

A call is released due to the S1AP specification cause

ConnRelease_S1AP_LINK_FA IL

A call is released due to the S1 SCTP link failure

ConnRelease_S1AP_RO_TO

A call is released due to the S1AP relocoverall timeout (not received)

ConnRelease_S1AP_SIG_FAI L

A call is released due to receiving S1AP signaling

ConnRelease_S1AP_SIG_TO

A call is released due to S1AP signaling timeout (not received)

ConnRelease_X2AP_CU_FAIL

A call is released due to the X2AP specification cause

ConnRelease_X2AP_LINK_FA IL

A call is released due to the X2 SCTP link failure

ConnRelease_X2AP_RO_TO

A call is released due to the X2AP relocoverall timeout (not received)

ConnRelease_X2AP_SIG_FAI L

A call is released due to receiving X2AP signaling

ConnNo

Average number of RRC connections during a time period

ConnMax

Maximum number of RRC connections during a time period

ConnTot

Summation of the collected ConnNo

ConnCnt

Count of the collected ConnNo

ReleaseCallHoldingTime

Average holding time of RRC connection. This is collected when a call is released.

ReleaseCallHoldingTimeTot

Summation of the collected ReleaseCallHoldingTime

ReleaseCallCnt

Call Release Count


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Type Name

Type Description

RRC_CONN_PLMN

ConnNo_PLMN

Average number of RRC connections per PLMN during a time period

ConnMax_PLMN

Maximum number of RRC connections per PLMN during a time period

ConnTot_PLMN

Summation of the collected ConnNo_PLMN

ConnCnt_PLMN

Count of the collected ConnNo_PLMN

ConnEstabTime

Average RRC Connection setup time

ConnEstabTimeMax

Maximum RRC Connection setup time

ConnEstabTimeTot

Summation of the collected ConnEstabTime

ConnEstabTimeCnt

Count of the collected ConnEstabTime

ConnReEstabTime

Average RRC Connection reestablishment time

ConnReEstabTimeMax

Maximum RRC Connection reestablishment time

ConnReEstabTimeTot

Summation of the collected ConnReEstabTime

ConnReEstabTimeCnt

Count of the collected ConnReEstabTime

CallDrop_ECCB_DSP_AUDIT _RLC_MAC_CALL_RELEASE

Call drop (abnormal release) count due to no call in RLC and MAC block

CallDrop_ECCB_RCV_RESET _REQUEST_FROM_ECMB

Call drop (abnormal release) count due to reset request from ECMB

CallDrop_ECCB_RCV_CELL_ RELEASE_IND_FROM_ECMB

Call drop (abnormal release) count due to cell release indication from ECMB

CallDrop_ECCB_RADIO_LINK _FAILURE

Call drop (abnormal release) count due to radio link failure

CallDrop_ECCB_DSP_AUDIT _MAC_CALL_RELEASE

Call drop (abnormal release) count due to no call in MAC block

CallDrop_ECCB_ARQ_MAX_ RE_TRANSMISSION

Call drop (abnormal release) count due to ARQ failure (no ACK is received after maximum retransmission)

CallDrop_ECCB_DSP_AUDIT _RLC_CALL_RELEASE

Call drop (abnormal release) count due to no call in RLC block

CallDrop_ECCB_TMOUT_rrcC onnectionReconfig

Call drop (abnormal release) count due to RRC signaling timeout (not received) during the RRC Connection Reconfiguration

CallDrop_ECCB_TMOUT_rrcC onnectionReEstablish

Call drop (abnormal release) count due to RRC signaling timeout (not received) during the RRC Connection Reestablishment

CallDrop_ECCB_S1_SCTP_O UT_OF_SERVICE

Call drop (abnormal release) count due to S1 failure

RRC_TIME

RRC_RESETUP_TIME

CALL_DROP


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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification


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LTE-SW0321, UE Context Management INTRODUCTION The eNB maintains UE contexts while the UEs are in the RRC_CONNECTED state, and supports Initial Context Setup, UE Context Release, and Modification according to requests from the MME.

BENEFIT The operator can maintain UE context for its subscribers in the RRC_CONNECTED state.

DEPENDENCY AND LIMITATION Limitation Need UE IOT for security context modification.

FEATURE DESCRIPTION Initial Context Setup eNB performs Initial Context Setup procedures when it receives INITIAL CONTEXT SETUP REQUEST message from MME. Initial Context Setup procedures are used for call setup. eNB creates UE context for the UE so that it can process UE associated signaling and data transmission/reception. On receiving INITIAL CONTEXT SETUP REQUEST message from MME, eNB determines whether the call setup is possible or not, based on the status of resources at that moment. If there are available resources, eNB performs RRC Connection Reconfiguration procedures with the UE for resource reconfiguration and transmits INITIAL CONTEXT SETUP RESPONSE to the MME, according to 3GPP TS36.413. Usually, Initial Context Setup procedures include E-RAB setup procedures. In the following figure, UE initiated Service Request trigers Initial Context Setup procedures.


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UE performs the random access and RRC connection establishment procedures with eNB for call setup.

1 The eNB transmits the Initial UE message to the MME to establish the connection. The NAS message received from the UE and SERVICE REQUEST are included in this message.

aThe eNB uses the eNB-UE-S1AP-ID to uniquely identify the UE. bEPS attach type may be EPS Attach (or) Combined EPS/IMSI Attach. cThe UE Identity is specified is IMSI (If the UE is not registered with the network) and Old GUTI (Subsequent attach requests identify the UE with the Old GUTI).

2 If necessary, the NAS security setup or authentication procedures are performed. 3 The MME transmits the Initial Context Setup request to the eNB. Information required for E-RAB(s) setup, UE contexts required by the eNB to control the UE, the NAS message to be sent to the UE and SERVICE ACCEPT are included in the Initial Context Setup request.

aS1AP Initial Context Setup Request contains a request to establish a context between MME-eNodeB and the message containing SGW tunneling information.


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bNAS Attach Accept Message acknowledges the successful Attach to the UE, eNodeB will pass this message to the UE.

cActivate Default Bearer Request Message initiates the default bearer setup on the UE and the eNodeB will pass this message to the UE.

4 The eNB determines whether call setup is possible based on the information received from the MME. If possible, it performs the AS security activation procedure with the UE.

5 The eNB reallocates internal resources for DRB(s) setup and transmits RRC Connection Reconfiguration to the UE.

6 The UE sets up the additional DRB(s) specified by RRC Connection Reconfiguration and responds to the eNB with RRC Connection Reconfiguration Complete.

7 The eNB responds to the MME with the Initial Context Setup response. Setup success/failure results for each E-RAB are included in the Initial Context Setup response. If eNB detects a failure in the path to the SGW, it responds to the MME with Initial Context Setup Failure message, where the cause value is 'Transport Resource Unavailable'.

aThis message confirms the establishment of the GTP tunnel on the S1-U Interface.

bThe message contains information about the RABs that are being established at startup.

cEach RAB will have an E-RAB ID, transport layer IP address on the eNodeB and eNodeB GTP Tunneling ID (TEID) for the eNodeB side.

8 The MME performs the Modify Bearer procedure with the S-GW/P-GW. When the path between eNB and Serving GW is in failure state, eNB responds with INITIAL CONTEXT SETUP FAILURE message instead of INITIAL CONTEXT SETUP RESPONSE message. It makes MME to disconnect the call of the UE.

UE Context Modification The eNB performs the UE context modification procedure upon the MME‟s request. It can change the security context, UE AMBR and SPID through the UE context modification procedure. When receiving the UE Context Modification request from the MME, the eNB changes the UE context using the value included in the message and transmits the UE Context Modification response to the MME. If the security context was changed, it performs the RRC Connection Reconfiguration procedure with the UE and then responds to the MME. It uses the UE context modification procedure to change the UE context of the connected UE. The following UE contexts can be changed through the UE context modification procedure.

UE Aggregate Maximum Bit Rate (UE AMBR) UE Security Capabilities eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Security Key Subscriber Profile ID for RAT/Frequency priority (SPID) CSG Membership Status Registered LAI The UE context modification procedure is as follows.

If the HSS initiated UE context modification procedure, the HSS performs the subscriber data modification procedure with the MME.

1 If UE context modification is required, the MME transmits the Context Modification request to the eNB.

2 The eNB changes the UE context based on the information included in the UE Context Modification Request message and transmits the UE Context Modification Response message to the MME. If the security context was changed, it performs the RRC Connection Reconfiguration procedure with the UE and then responds to the MME.

UE Context Release The eNB performs the UE context release procedure upon the MME‟s request. The UE context release procedure is used for releasing a call from the connected UE. The MME initiated UE context release is performed based on MME‟s decision or the eNB initiated UE context release is performed upon the request from the eNB. When receiving the UE Context Release Command message from the MME, the eNB performs the RRC Connection Release procedure with the UE and then transmits the UE Context Release Complete message to the MME.

The UE context release procedure is used for call release (active-to-idle transition).

The UE context release procedure is as follows.


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If the eNB initiated UE context release procedure, the eNB transmits the UE Context Release request to the MME to request for call release.

1 If S1 release is necessary, the MME performs the Release Access Bearer procedure with the S-GW.

2 The MME transmits the UE Context Release command to the eNB for S1 release. 3 The eNB transmits RRC Connection Release to the UE. 4 The eNB performs the RRC Connection Release procedure with the UE and then responds to the MME with the UE Context Release Complete.

SYSTEM OPERATION How to Activate This feature is basically enabled and operator cannot disable.

Key Parameters Security algorithm can be set by the following parameters using command RTRVSECU-INF/CHG-SECU-INF. Parameter

Description

INTEGRITY_E A_PRIOR

The integrity protection algorithm supported by the eNB EIA0: NULL EIA1: SNOW 3G EIA2: AES

CIPHER_EA_P RIOR

The ciphering algorithm supported by the eNB EEA0: NULL EEA1: SNOW 3G EEA2: AES


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Type Name

Type Description

ERAB_ESTAB

EstabInitAttNbr

INITIAL CONTEXT SETUP REQUEST count.

EstabInitSuccNbr

INITIAL CONTEXT SETUP RESPONSE count.

ErabInitFailNbr_CP_CC_TO

Initial E-RAB setup fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, and GTP).

ErabInitFailNbr_CP_CC_FAIL

Initial E-RAB setup fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block.

ErabInitFailNbr_UP_GTP_FAIL

Initial E-RAB setup fails due to the failure in the GTP block.

ErabInitFailNbr_UP_MAC_FAIL

Initial E-RAB setup fails due to the failure in the MAC block.

ErabInitFailNbr_UP_ PDCP_FAIL

Initial E-RAB setup fails due to the failure in the PDCP block.

ErabInitFailNbr_UP_RLC_FAIL

Initial E-RAB setup fails due to the failure in the RLC block.

ErabInitFailNbr_RRC_ SIG_FAIL

Initial E-RAB setup fails due to receiving RRC signaling.

ErabInitFailNbr_RRC_ SIG_TO

Initial E-RAB setup fails due to RRC signaling timeout (not received).

ErabInitFailNbr_CP_BH_CAC_FAIL

Initial E-RAB setup fails due to Backhaul QoS based CAC.

ErabInitFailNbr_CP_ CAPA_CAC_FAIL

Initial E-RAB setup fails due to Capacity based CAC.

ErabInitFailNbr_CP_QOS_CAC_FAIL

Initial E-RAB setup fails due to Air QoS based CAC.

ErabInitFailNbr_S1AP_ CU_FAIL

Initial E-RAB setup fails due to the S1AP specification cause.

ErabInitFailNbr_S1AP_ LINK_FAIL

Initial E-RAB setup fails due to the S1 SCTP link failure.

ErabInitFailNbr_S1AP_ SIG_FAIL

Initial E-RAB setup fails due to receiving S1AP signaling.

EraseAttbyEnb_CP_CC_TO

eNB initiated UE Context Release fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, and GTP).

EraseAttbyEnb_CP_CC_FAIL

eNB initiated UE Context Release fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block.

EraseAttbyEnb_UP_GTP_FAIL

eNB initiated UE Context Release fails due to the failure in the GTP block.

EraseAttbyEnb_UP_MAC_FAIL

eNB initiated UE Context Release fails due to the failure in the MAC block.

ERAB_ERASE_ENB


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ERAB_ERASE

ERAB_TIME

ERAB_SESSION_UE

S1SIG

Type Name

Type Description

EraseAttbyEnb_UP_MAC_UE_INACT

eNB initiated UE Context Release fails due to user inactivity.

EraseAttbyEnb_UP_ PDCP_FAIL

eNB initiated UE Context Release fails due to the failure in the PDCP block.

EraseAttbyEnb_UP_RLC_FAIL

eNB initiated UE Context Release fails due to the failure in the RLC block.

EraseAttbyEnb_RRC_HC_TO

eNB initiated UE Context Release fails due to HO preparation timeout (not received HO command).

EraseAttbyEnb_RRC_SIG_FAIL

eNB initiated UE Context Release fails due to receiving RRC signaling.

EraseAttbyEnb_RRC_SIG_TO

eNB initiated UE Context Release fails due to RRC signaling timeout (not received).

EraseAttbyEnb_S1AP_ CU_FAIL

eNB initiated UE Context Release fails due to the S1AP specification cause.

EraseAttbyEnb_S1AP_ RO_TO

eNB initiated UE Context Release fails due to the S1AP relocoverall timeout (not received).

EraseAttbyEnb_S1AP_ SIG_TO

eNB initiated UE Context Release fails due to S1AP signaling timeout (not received).

EraseAttbyEnb_X2AP_ RO_TO

eNB initiated UE Context Release fails due to the X2AP relocoverall timeout (not received).

EraseAtt

UE CONTEXT RELEASE COMMAND count.

EraseSucc

UE CONTEXT RELEASE COMPLETE count.

EstabTimeAvg

Average time of Initial E-RAB set-up and additional E-RAB setup.

EstabTimeMax

Max. time of Initial E-RAB set-up and additional E-RAB setup.

EstabTimeTot

Total time of Initial E-RAB set-up and additional E-RAB setup.

EstabTimeCnt

Counts of Initial E-RAB set-up and additional E-RAB setup.

SessionTimeUEAvg

Average In-Session time.

SessionTimeUETot

Total In-Session time.

SessionTimeUECnt

Counts of In-session time.

S1ConnEstabAtt

INITIAL UE MESSSAGE count.

S1ConnEstabSucc

INITIAL CONTEXT SETUP REQUEST count.

S1ConnEstabFail_CpCcFail

S1 Connection Establishment fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block.


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Type Name

Type Description

S1ConnEstabFail_S1apCuFail

S1 Connection Establishment fails due to the S1AP specification cause.

S1ConnEstabFail_S1apLinkFail

S1 Connection Establishment fails due to the S1 SCTP link failure.

S1ConnEstabFail_S1apSigFail

S1 Connection Establishment fails due to receiving S1AP signaling.

S1ConnEstabFail_S1apSigTo

S1 Connection Establishment fails due to S1AP signaling timeout (not received).

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36. 413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP)


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LTE-SW0322, E-RAB Management INTRODUCTION ERAB is a bearer connection between an eNB and a Serving GW (S-GW). An MME initiates E-RAB setup, modification, and release procedures, and it also requests an eNB to modify the E-RAB QoS characteristics. The E-RAB Management feature performs all these procedures according to 3GPP TS36.413. This feature allows the eNB and MME to set up an E-RAB connection so that the eNB and the S-GW transmit user packets in uplink and downlink through the GTP tunnel. They distinguish each E-RAB bearer by Tunnel Endpoint Identifier (TEID).

BENEFIT Operator can provide EPS bearer service to its subscribers and manage E-RAB resources for user data transport.

DEPENDENCY None

LIMITATION None


FEATURE DESCRIPTION This feature has the following three main functions:

E-RAB Setup E-RAB Modification E-RAB Release


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E-RAB Setup The eNB can add E-RAB for a new service to a connected UE through E-RAB setup procedure. When receiving the E-RAB Setup Request message from the MME, the eNB considers the current resource usage status and determines whether a new bearer can be added. If a new E-RAB can be added, the eNB performs the RRC Connection Reconfiguration procedure with the UE for resource reconfiguration of the new DRB and transmits the E-RAB Setup Response message to the MME. Each E-RAB will have the following information: E-RAB ID, Transport Layer IP Address on the eNB, GTP Tunneling ID (TEID) for the eNB side, QCI to assign session priority, maximum bit rate for the E-RAB, and guaranteed bit rate for the E-RAB. Figure below depicts the E-RAB setup procedure.

1 The P-GW transmits the Create Bearer request to the S-GW to add the new ERAB.

2 The S-GW transmits the Create Bearer request to add the new E-RAB. 3 The MME transmit the E-RAB Setup request to start the E-RAB setup procedure. QoS information of the E-RAB(s) to be added, the NAS message to be sent to the UE, and ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST are included in the E-RAB Setup request.

4 When receiving the E-RAB Setup request from the MME, the eNB determines whether a new E-RAB(s) can be added. If possible, the eNB reallocates internal resources and transmits RRC Connection Reconfiguration to the UE. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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5 The UE adds the new DRB(s) specified by RRC Connection Reconfiguration and then replies to the eNB with RRC Connection Reconfiguration Complete.

6 The eNB responds to the MME with the E-RAB Setup response. Setup success/failure results for each E-RAB are included in the E-RAB Setup response.

7 The UE transmits the NAS message and ACTIVATE DEDICATED EPS BEARER CONTEXT RESPONSE.

8 The eNB transmits the NAS received from the UE to the MME. 9 The MME transmits the Create Bearer response to the S-GW. 10 The S-GW transmits the Create Bearer response to the P-GW. E-RAB Modification The eNB can change the QoS setting of a bearer (E-RAB) already in service through E-RAB modification procedure. Using this procedure, operator can change UE AMBR for non-GBR bearer and E-RAB Level QoS parameters (QCI, ARP and GBR QoS Information) for GBR bearer. Figure below depicts the E-RAB modification procedure.

1 The P-GW transmits Update Bearer Request to S-GW to change QoS setting. 2 The S-GW transmits Update Bearer Request to MME to change QoS setting.


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3 The MME starts the E-RAB modification procedure by transmitting E-RAB Modify Request to the eNB. The E-RAB Modify Request has the QoS information of E-RAB(s) to change, NAS message to send to an UE, and MODIFY EPS BEARER CONTEXT REQUEST.

4 When the eNB receives E-RAB Modify Request from the MME, it judges if it is possible to change the QoS setting of the E-RAB(s). If possible, it re-allocates internal resources and transmits RRC Connection Reconfiguration to the MS.

5 The MS changes the QoS setting of DRB(s) that is specified in RRC Connection Reconfiguration and replies RRC Connection Reconfiguration Complete to the eNB.

6 The eNB replies E-RAB Modify Response to the MME. The E-RAB Modify Response has the success or failure of QoS setting change per E-RAB.

7 The UE transmits NAS message, MODIFY EPS BEARER CONTEXT RESPONSE.

8 The eNB transmits the NAS message received from the UE to the MME. 9 The MME transmits Update Bearer Response to the S-GW. 10 The S-GW transmits Update Bearer Response to the P-GW. E-RAB Release The eNB can release specific bearer service of a connected UE through E-RAB release procedure. This procedure is performed by request from MME, and MME requests E-RAB release based on its own decision (MME initiated E-RAB release) or as following action after an indication from eNB (eNB initiated E-RAB release). When E-RAB RELEASE REQUEST message is received from MME, eNB performs RRC connection reconfiguration procedure with UE to release the corresponding Data Radio Bearer (DRB). When the DRB is released successfully, eNB returns E-RAB RELEASE RESPONSE message to MME. Figure below depicts E-RAB release procedure.


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0) If the eNB initiated E-RAB release procedure, the eNB transmits the E-RAB Release indication to the MME to notify the release of a specific E-RAB. The MME transmits the Delete Bearer command to the S-GW for E-RAB release.

1 The S-GW transmits the Delete Bearer command for E-RAB release. The P-GW transmits the Delete Bearer request to the S-GW for E-RAB release.

2 The S-GW transmits the Delete Bearer request to the MME for E-RAB release. 3 The MME initiates the E-RAB release procedure by transmitting the E-RAB Release command. ID(s) of the E-RAB(s) to be released, the NAS message to be sent to the UE and DEACTIVATE EPS BEARER CONTEXT REQUEST are included in the E-RAB Release command.

4 When receiving the E-RAB Release command from the MME, the eNB transmits RRC Connection Reconfiguration to the UE.

5 The UE releases the DRB(s) specified by RRC Connection Reconfiguration and then replies to the eNB with RRC Connection Reconfiguration Complete.

6 The eNB responds to the MME with the E-RAB Release response. 7 The UE transmits the NAS message and DEACTIVATE EPS BEARER CONTEXT RESPONSE.

8 The eNB transmits the NAS received from the UE to the MME. 9 The MME transmits the Delete Bearer response to the S-GW. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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10 The S-GW transmits the Delete Bearer response to the P-GW.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure For standard QCI E-RABs, this feature runs automatically, and in cannot be disabled.

For operator specific QCIs, run CHG-QCI-VAL to equip new QCIs to be used. Deactivation Procedure This feature does not need to be deactivated.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There are no specific parameters associated with this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-QCI-VAL Parameter

Description

QCI

QoS Class Identifier (QCI) index. The range is from 0 to 255. The QCI defined in the standard is 1 to 9. The user can use QCI values 0 and 10-255.

STATUS

Whether the QoS Class Identifier (QCI) is used. EQUIP: The QCI is used in the eNB. N_EQUIP: The QCI is not used in the eNB.

Counters and KPI Table below outlines the main counters associated with this feature. Family Display Name

Type Name

Type Description

ERAB_ESTAB_ADD

EstabAddAttNbr

ERAB SETUP REQUEST count

EstabAddSuccNbr

ERAB SETUP RESPONSE count


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ERAB_REL_ ENB

ERAB_REL

Type Name

Type Description

ErabAddFailNbr_CP_CC _TO

E-RAB setup fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP)

ErabAddFailNbr_CP_CC _FAIL

E-RAB setup fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block

ErabAddFailNbr_UP_GT P_FAIL

E-RAB setup fails due to the failure in the GTP block

ErabAddFailNbr_UP_M AC_FAIL

E-RAB setup fails due to the failure in the MAC block

ErabAddFailNbr_UP_PD CP_FAIL

E-RAB setup fails due to the failure in the PDCP block

ErabAddFailNbr_UP_RL C_FAIL

E-RAB setup fails due to the failure in the RLC block

ErabAddFailNbr_RRC_S IG_FAIL

E-RAB setup fails due to receiving RRC signaling

ErabAddFailNbr_RRC_S IG_TO

E-RAB setup fails due to RRC signaling timeout (not received)

ErabAddFailNbr_CP_BH _CAC_FAIL

E-RAB setup fails due to Backhaul QoS based CAC

ErabAddFailNbr_CP_CA PA_CAC_FAIL

E-RAB setup fails due to Capacity based CAC

ErabAddFailNbr_CP_Q OS_CAC_FAIL

E-RAB setup fails due to Air QoS based CAC

ErabAddFailNbr_S1AP_ CU_FAIL

E-RAB setup fails due to the S1AP specification cause

ErabAddFailNbr_S1AP_ LINK_FAIL

E-RAB setup fails due to the S1 SCTP link failure

ErabAddFailNbr_S1AP_ SIG_FAIL

E-RAB setup fails due to receiving S1AP signaling

ErabAddFailNbr_CP_CC _INTERACTION

E-RAB setup fails due to ongoing inter-eNB handover

RelAttbyEnbNbr_CP_C C_TO

eNB initiated E-RAB Release fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP)

RelAttbyEnbNbr_S1AP_ CU_FAIL

eNB initiated E-RAB Release fails due to the S1AP specification cause

RelAttNbr

ERAB RELEASE COMMAND count

RelSuccNbr

ERAB RELEASE RESPONSE count

RelFailNbr_CP_CC_FAI L

MME initiated E-RAB Release fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block

RelFailNbr_S1AP_SIG_ FAIL

MME initiated E-RAB Release fails due to receiving S1AP signaling

RelFailNbr_S1AP_CU_F AIL

MME initiated E-RAB Release fails due to the S1AP specification cause

RelActive

Number of active E-RABs abnormally released by eNB

RelFailNbr_CP_CC_INT ERACTION

MME initiated E-RAB Release fails due to ongoing intereNB handover

RelActive_ECCB_RADI O_LINK_FAIL

Number of active E-RABs abnormally released by eNB in case of radio link fail.

RelActive_ECCB_ARQ_

Number of active E-RABs abnormally released by eNB in


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ERAB_NUM

Type Name MAX_ReTransmission

Type Description case of ARQ MAX Retransmission.

RelActive_ECCB_TM_O UT_RRC_CONNECTIO N_RECONFIG

Number of active E-RABs abnormally released by eNB in case of Time Out RRC Connection Reconfiguration

RelActive_ECCB_TM_O UT_RRC_CONNECTIO N_REESTABLISH

Number of active E-RABs abnormally released by eNB in case of Time Out RRC Connection Reestablishment

UsageNbr

Average number of E-RABs during a time period

UsageNbrMax

Maximum number of E-RABs during a time period

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36. 413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP)


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LTE-SW0325, User Inactivity Timer Control INTRODUCTION The User Inactivity Timer Control feature allows an eNB to set an inactivity timer for singling and data services of a UE. When the timer expires, this feature releases the UE so the UE that has no traffic for a longer time does not occupy resources in the active status.

BENEFIT Operator can optimize the system utilization by changing the user inactivity timer. A longer inactivity timer allows UEs keep their connections longer even though there is no traffic flow over them. This reduces the amount of signaling messages among network elements such as UE, eNB and EPC. On the other hand, a shorter inactivity timer increases the number of UEs that the cell can serve under the coverage.

DEPENDENCY The value of the inactivity timer may affect the KPI. If the timer value is lower, resource efficiency goes higher. However, the UE is often released so its experience quality may become worse. When the timer value is higher, resource efficiency goes lower. However, the UE is released in a rare occasion when the timer value is low so its experience quality may become better.

LIMITATION None

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Value of inactivity timer may affect resource efficiency and UE battery consumption. (See DEPENDENCY section.)

FEATURE DESCRIPTION With this feature, the eNB can control the inactivity timer of the signaling and user data. It supports the following control functions:

Inactivity Timer Start Inactivity Timer Reset/Initialization eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Inactivity Timer Stop Inactivity Timer Expiry Inactivity Timer Start Figure below depicts the inactivity timer control during RRC Connection Setup procedure.

This procedure is made up of the following flows:

1 The eNB receives RRC Connection Request from the UE. 2 The eNB transmits the RRC Connection Setup message to the UE. 3 If the eNB receives the RRC Connection Setup Complete message, starts the signaling inactivity timer. During this time, the user data inactivity timer is set to the expired status.

4 If the uplink or downlink user data of the UE is transmitted and received, the eNB start the user data inactivity timer.

Inactivity Timer Reset/Initialization When the RRC connection setup is completed, the eNB can control inactivity timers as follows: Signaling Inactivity Timer Control If the signaling message specified by the UE or MME is received, then the eNB resets the signaling inactivity timer for the UE and initializes the existing set timer value for new start. User Data Inactivity Timer Control If the eNB receives the user data of the UE, it stops the user data inactivity timer for the UE and completes transmitting the user data. During this time, the user data inactivity timer of the UE is initialized than being restarted. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Inactivity Timer Stop The eNB stops the signaling and user data inactivity timers corresponding to the UE after transmitting the RRC Connection Release message to the UE. This process is the same as general resource collecting process.

When Inactivity Timer Expiry The eNB determines the UE is in the inactive status when the signaling and user data inactivity timer expire. It transmits the S1AP UE Context Release Request message to the MME by performing the UE context release procedure. With the cause value: user inactivity, the RRC connection responding to the UE is released. Figure below depicts an overall message flow when the inactivity timer expires.


1 When there is no user data between the eNB and the UE for a certain period of time, the user data inactivity timer expires.

2 When there is no specified signaling message between the eNB and UE for a certain period, the signaling inactivity timer expires.

3 If the signaling and user data inactivity timer expire, the eNB releases the call by performing the UE context release procedure.

Inactivity Timer Procedure with Intra-LTE Handover With this feature, the eNB controls the inactivity timer when intra-LTE handover. Calculating UE-InactiveTime IE Calculation of the remaining timer at each stage is as follows: [ue-InactiveTime IE calculation method] ue-InactiveTime = MAX (Init.Signaling Inactivity Timer, Init.User Data Inactivity Timer) - MAX (Remaining Signaling Inactivity Timer, Remaining User Data Inactivity Timer) Remaining Signaling Inactivity Timer = Init. Signaling Inactivity Timer - ue-InactiveTime IE Remaining User Data Inactivity Timer = Init. User Data Inactivity Timer - ue-InactiveTime IE


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If the value of the Remaining Signaling Inactivity Timer or Remaining User Data Inactivity Timer is 0 or less, it is considered as the timer has expired. X2 Handover Figure below depics the inactivity timer procedure during X2 handover.


1 The eNB receives the Measurement Report message from the UE and determines the handover. The source eNB calculates the UE-InactiveTime according to the operation of the inactivity timer.

2 The source eNB transmits the UE-InactiveTime to the target eNB through the X2AP Handover Request message.

3 The target eNB calculates and saves the remaining signaling and remaining user data inactivity time according to the operation of the target eNB inactivity timer after receiving the X2AP Handover Request message. During this time, the target eNB does not run the user data inactivity timer immediately.

4 The target eNB runs the user data and signaling timers separately after receiving the RRC Connection Reconfiguration Complete message. S1 Handover Figure below depicts the inactivity timer procedure during S1 handover.


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1 The source eNB determines the handover after receiving the Measurement Report message from the UE and calculates the ue-InactiveTime according to the operation of the inactivity timer.

2 The source eNB transmits the ue-InactiveTime to the target eNB via the MME by using the S1 handover procedure.

3 The target eNB calculates and saves the remaining signaling and user data inactivity times according to the operation of the target eNB inactivity timer after receiving the S1AP Handover Request message. During this time, the target eNB does not start the user data timer.

4 The target eNB runs the user data and signaling timers separately after receiving the RRC Connection Reconfiguration Complete message.



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How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-INACT-TIMER and set INTERNAL_USER_INACTIVITY to be larger than 0 to enable the user inactivity timer for target PLMN_IDX and QCI. Deactivation Procedure For target PLMN_IDX and QCI, run CHG-INACT-TIMER and set INTERNAL_USER_INACTIVITY to be 0 to disable the user inactivity timer.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-INACT-TIMER/RTRV-INACT-TIMER Parameter

Description

INTERNAL_USER_INACTIVITY

This parameter is the User inactivity timer value per QCI. A different User inactivity timer value can be set for each QCI by executing this command. As User inactivity timer is closely related to call release, if possible, use the default value without changing it. It is a timer value that operates in seconds. If the operating User inactivity timer value is 65535, a call may not be detached for 65535 seconds and because this may cause serious problems for the battery usage of the UE, if possible, use a value that is less than 30 seconds.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-INACT-TIMER/RTRV-INACT-TIMER Parameter

Description

QCI

This parameter is the QoS Class Identifier (QCI). The range is 0-255. The standard QCI defined in the standard document is 1-9. 0 and 10255 can be used by the operator optionally. [Related Specifications] 3GPP TS 23.203 [Table 6.1.7] Standardized QoS characteristics.

PLMN_IDX

The plmn index to be changed or retrieved. PLMN ID corresponding to the selected plmnIdx is mapped to the PLMN ID which is retrieved/changed by command RTRV/CHG-ENBPLMN-INFO with the same plmnIdx number.)

INTERNAL_USER_INACTIVITY

This parameter is the User inactivity timer value per QCI. A different User inactivity timer value can be set for each QCI by executing this command. As User inactivity timer is closely related to call release, if possible, use the default value without changing it. It is a timer value that


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Description operates in seconds. If the operating User inactivity timer value is 65535, a call may not be detached for 65535 seconds and because this may cause serious problems for the battery usage of the UE, if possible, use a value that is less than 30 seconds.

Parameter Descriptions of CHG-PLMNSIGTIMER-INFO/RTRVPLMNSIGTIMER-INFO Parameter

Description

PLMN_IDX

The plmn index to be changed or retrieved. PLMN ID corresponding to the selected plmnIdx is mapped to the PLMN ID which is retrieved/changed by command RTRV/CHG-ENBPLMN-INFO with the same plmnIdx number.)

INTERNAL_SIGNALING_INACTIVI TY_TIMER

This parameter is the inactivity timer information for a signaling message. An eNB starts an inactivity timer for a signaling message after a UE is attached. Signaling Inactivity is initialized if a message containing NAS PDU information is received from a UE or MME and a timer is expired if a message containing the NAS PDU information is not received while timer is operating. When timer is expired, a call is detached if the User inactivity timer is also expired. If the User inactivity timer is not expired, the call is waiting until the User inactivity timer is expired. Unlike other timers, this timer operates in the sec. unit and it is recommended not to change it because the default is a service provider's requirement.


Type Name

Type Description

CSL

[0x0341] ECC_USER_INACTIVITY

The cumulated number of Call Release due to the expiration of both Signaling Inactivity Timer and User Inactivity Timer.



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LTE-SW0327, SIPTO Support INTRODUCTION There is an ever increasing demand for higher bandwidth and low latency application. This increase in traffic further loads the LTE Core network resulting in increased CAPEX and OPEX for the operator. Traffic offloading has been attracting attention from operators as one solution to the problem of increased traffic. Traffic offloading is a technology to veer traffic from User plane directly to the internet from LTE eNodeB. SIPTO (Selective IP Traffic Offload) mechanisms are intended to minimize the amount of data traffic that traverses the Core Network, thereby reducing the backhaul requirements. This feature enables the UE to offload traffic to the nearest network node (PDN GW) from where UE is located. E-UTRAN supports SIPTO at the Local Network with a standalone GW where SGW and L-GW are collocated.

BENEFIT Offloads Core Network from the specific traffic type desired by the operator. Overload Control Feature by offloading traffic to gateway. Reduces Operator‟s CAPEX and OPEX

DEPENDENCY Required Network Elements MME, MME to Support MME-triggered S-GW relocation without UE mobility through the E-RAB MODIFY REQUEST message

Others Release 12 UE to support SIPTO@LN for standalone GW.

LIMITATION N/A



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FEATURE DESCRIPTION SIPTO Architecture SIPTO service enables an operator to offload selected traffic towards a network close to the user equipment (UE) point of attachment to the access network. It is based on an enhanced gateway selection function that has the capability to select a mobile core network gateway close to the eNB. When a user requests to access a service that the operator has defined to be offloaded locally through SIPTO offload, the packet data network (PDN) connection will therefore be established through a local PDN gateway (L-GW) defined for SIPTO traffic offload. Samsung EUTRAN supports SIPTO with standalone L-GW architecture and is illustrated in below diagram. This architecture is called as SIPTO Above RAN architecture.

GW Selection The S-NAPTR (Straightforward-Name Authority Pointer) based selection of the SGW (based on TAI) gives the shortest user plane path from the UE to the S-GW from the S-NAPTR ordering. Topological naming should be employed to find the shortest user plane path from the S-GW to the P-GW based on the topological closeness. With this approach, EPC selects an S-GW and P-GW to achieve the shortest user plane path to the UE for a SIPTO enabled APN. EPC selects P-GW based on the TA information(in EPC local configuration) SIPTO@LN with standalone GW (with S-GW and L-GW collocated, Release 12) SIPTO@LN is supported using a standalone GW is the architecture that is deployed in the local network. The MME may decide to trigger S-GW relocation without UE mobility.If a handover is performed, SIPTO@LN PDN connection is released.eNB must support signalling of its LHN ID to the MME in the INITIAL UE MESSAGE, UPLINK NAS TRANSPORT, HANDOVER NOTIFY and PATH SWITCH REQUEST messages.In order to select an appropriate Local GW (L-GW) for SIPTO at the local network service, the GW selection function in the MME uses the APN and the Local Home Network ID during the DNS interrogation as specified in TS 29.303 to find the GW identity of the L-GW to be selected.


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The eNB should support for MME-triggered S-GW relocation without UE mobility through the E-RAB MODIFY REQUEST message. LHN ID is configured locally in each eNB of the Local Home Network. Based on the Operator Configuration, LHN ID could be retrieved. If Operator Configuration is not available, then LHN ID could be identified in a PLMN-ID. The eNBs in the same LHN shall have the same LHN-ID.

eNB Impact LHN ID Support In the SIPTO@LN with standalone GW architecture, there is the concept of Local Home Network (LHN). Local Home Network is a set of eNBs belonging to a local network with a standalone local GW-which consists of a co-located Serving Gateway and a Local Gateway. These eNBs have IP connectivity for SIPTO LGW. There can be many Local Home Networks per PLMN. Each LHN is identified uniquely by its own LHN-ID. With this feature, eNB supports configuration of the Local Home Network ID on per PLMN basis. The Local Home Network identifier (LHN ID) uniquely identifies a local home network. The syntax of Local Home Network-ID FQDN is provided in the following format.

lhn< LHN name >.lhn.epc.mnc.mcc.3gppnetwork.org where the length and content is an operator choice.The LHN ID is transported in S1AP messages as below and eNB supports configuration of LHN ID in an string format of size 32 to 256 bytes. When LHN ID IE is received in the INITIAL UE MESSAGE, PATH SWITCH REQUEST, HANDOVER NOTIFY and UPLINK NAS TRANSPORT message, the MME shall, if supported, use it for SIPTO@LN operation as specified in TS 23.401.


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ERAB Setup for SIPTO@LN When UE requests for a new PDN connection for which a local GW can be selected, MME selects the local SGW and new ERAB is setup in eNB. From an eNB perspective, this may result in two separate scenarios, one involving INITIAL CONTEXT SETUP REQUEST message and another with ERAB SETUP REQUEST message. When MME receives the Local Home Network ID from eNB in INITIAL UE MESSAGE, it is used to select the appropriate GW for SIPTO@LN service with a stand-alone GW (with S-GW and L-GW collocated). The PDN GW selection function in MME uses the APN and the Local Home Network ID during the DNS interrogation as specified in TS 29.303 to find the PDN GW identity. Upon selecting the S-GW co-located with LGW, MME further provides the S-GW (with collocated L-GW) information for the bearer that is allowed for SIPTO offloading in INITIAL CONTEXT SETUP REQUEST message with Transport Layer address and GTP tunnel Id of the selected S-GW in ERAB to be Setup item IEs. Below figure illustrates an example scenario.


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When MME receives the LHN ID in UPLINK NAS TRASPORT and if the UE is requesting a new PDN connection for which a local GW selection is possible, MME may select a local SGW. If the UE is already connected to the same S-GW for an existing PDN connection, this would result in a S1AP ERAB SETUP REQUEST message with the SGW (collocated with LGW) information in ERAB To Be Setup Item IEs. Below figure illustrates example scenario.

In the S1AP UPLINK NAS TRANSPORT message, eNB provides LHN ID configured for the UE selected PLMN. When MME receives Local Home Network ID in UPLINK NAS TRANSPORT message, it is used to determine if the UE has left its current local network and if S-GW relocation is needed. In this example, UE has not left its current LHN. Upon receiving the NAS PDN connectivity request, MME performs GW selection using APN and LHN ID and selects an S-GW collocated with L-GW. MME sends Create Session Request to SGW with LHN ID and S-GW in turn sends Create Session Request to L-GW. Once the UL GTP tunnel id information is available from S-GW/L-GW, MME sends S1AP ERAB SETUP REQUEST message with S-GW/L-GW IP address and GTPTEID information to eNB and eNB setups the bearer and provides downlink GTP TEID information back to MME, similar to regular ERAB setup procedure.


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eNB support for MME-triggered S-GW relocation Macro S-GW may be allocated for PDN connection in the operator's network. If a new PDN connection is requested by the UE that requires that a local S-GW is selected to provide for SIPTO at the Local Network, S-GW relocation from the macro S-GW to the local S-GW shall be performed as specified in clause 5.10.4 [TS 23.401]. The MME sends the Serving GW Relocation Notification (Serving GW addresses and uplink TEID(s) for user plane) message to eNodeB. The eNodeB starts using the new Serving GW address(es) and TEID(s) for forwarding subsequent uplink packets.

UE has a PDN connection for which the local GW is not involved. When a UE requests for a PDN connection for which a local GW can be selected, MME relocates the SGW to local GW even for the already existing bearer. Please note that, generally SGW relocation is triggered by UE mobility (Tracking Area Update or Intra-LTE mobility), but in this case, the SGW relocation is not triggered by UE mobility. As part of SGW relocation in this scenario, the transport layer address and GTP tunnel id for the existing bearer needs to be modified at eNB, and hence MME sends S1AP ERAB MODIFY REQUEST with new GW information to eNB along with S1AP ERAB SETUP REQUEST for the new SIPTO bearer. Typically eNB receives S1AP ERAB MODIFY REQUEST to modify QoS parameters, but in this case the transport layer address and GTP-TEID is modified.


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How to Activate This section provides the information that you need to configure the feature. Precondition There are no specific preconditions to activate this feature. Activation Procedure Run CHG-SIPTO-CONF and set siptoAllowed to True. Deactivation Procedure Run CHG-SIPTO-CONF and set siptoAllowed to False.


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Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SIPTO-CONF/RTRV-SIPTO-CONF Parameter

Description

SIPTO_ALLOWED

It should decide whether to support the SIPTO feature in eNB. Normal operation is able if Rel.12 MME exists only. False: LHNid is not transmitted to MME. True: LHN id is transmitted to MME.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SIPTO-CONF/RTRV-SIPTO-CONF Parameter

Description

LHN_ID

It transmits the configured LHN ID to MME in case SIPTO_ALLOWED == TRUE (SIPTO support feature is True). Refer the TS 23.003 for detailed configuration and it should be configured with more than 32 digits at least. Ex) For MCC = 999, MNC = 99, and lhn name SAMSUNGLTE, LHN ID = lhnSAMSUNGLTE.lhn.epc.mnc099.mcc999.3gppnetwork.org


REFERENCE [1] 3GPP Evolved Universal Terrestrial Radio Access Network (E-UTRAN) TS 36.300 (Release 12) [2] 3GPP Evolved Universal Terrestrial Radio Access Network (E-UTRAN) S1 Application Protocol (S1AP) TS 36.413 (Release 12) [3] 3GPP General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Access TS 23.401 (Release 12) [4] 3GPP Local IP Access and Selected IP Traffic Offload (LIPA-SIPTO) TR 23.829 (Release 12) [5] 3GPP Domain Name System Procedures TS 29.303 (Release 12)


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LTE-SW0501, S1 Interface Management INTRODUCTION The S1 interface management feature manages the S1-MME signaling associated between an eNB and an MME. This feature also includes S1-U path management between the eNB and an SGW.

BENEFIT Operator can manage the signaling associations between the eNB and the EPC such as setting up, resetting S1 interface and recovering from errors.

Operator can monitor S1-U path status between the eNB and the SGW.

DEPENDENCY Required Network Elements MME

Related Radio Technology E-UTRAN (LTE)

Interface & Protocols S1-AP, SCTP, GTP

Prerequisite Features COM-IP0401, SCTP

LIMITATION The eNB can connect to up to 16 MMEs at the same time. The eNB can communicate with any SGWs informed by the MME without the limitation on the number of SGWs as long as there is IP connectivity between the eNB and the SGW.

In some operator's network, IPsec tunnelling is used between the eNB and a SeGW. S1 signaling and data traffic is delivered from/to the EPC through the IPsec tunnel.


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SYSTEM IMPACT Interdependencies between Features Interdependent Feature: LTE-SW0504 MME Selection and Load Balancing This feature is part of LTE-SW0504 MME Selection and Load Balancing which selects an appropriate MME for a new call in the following way:

1 The eNB monitors the status of S1 connections up to 16 MMEs via LTESW0501 S1 Interface Management and then, it considers MMEs with available S1 connection for a new call (excluding MMEs with unavailable S1 connection).

2 The eNB learns Relative MME Capacity (RMC) of each MME via LTESW0501 S1 Interface Management and then, it selects the MME by wellknown weighted round robin method where RMC works as weight. Interdependent Feature: LTE-SW5001 Multiple PLMN Support This feature is part of LTE-SW5001 Multiple PLMN Support in the following way

1 The eNB learns which PLMNs each MME serves via LTE-SW0501 S1 Interface Management and then

2 The eNB periodically broadcasts multiple PLMN IDs (up to six) in system information and routes signaling for call control to the corresponding MME based on the selected PLMN ID by UE;

FEATURE DESCRIPTION This feature has the following main functions:

S1 Setup S1 Reset Error Indication eNB Configuration Update MME Configuration Update Keep Alive between eNB and MME Path Management between eNB and SGW When the eNB starts, the eNB performs S1 setup procedures with the MME according to 3GPP TS36.413, and they manage the connection by exchanging SCTP Heartbeat, S1 Reset, eNB/MME Configuration Update, and Error Indication message. Once the eNB and the MME setup an E-RAB connection, the eNB and the SGW can transmit user packets unlink and downlink through GTP tunnel. They distinguish each E-RAB bearer by Tunnel Endpoint Identifier (TEID). The eNB supports S1-U path management function as per 3GPP TS29.281. The following sub sections explain how to configure and manage S1 interface (S1MME and S1-U interface). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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S1 Setup The S1 Setup procedure is the first S1AP procedure after a Transport Network Layer(TNL) association has been made. When this procedure is performed, the application level configuration data between the eNB and the MME, if there was, is removed and replaced with the newly received data. During S1 setup procedure, the eNB sends its basic application level configuration data such as Global eNB ID, Supported Tracking Area list consisting of PLMN and Tracking Area Code, and Default paging DRX and the MME sends its list of served GUMMEIs, Relative MME capacity and so on as well. If the eNB initiating the S1 SETUP procedure on (or more) CSG cell(s), the S1 SETUP REQUEST message shall contain the CSG ID(s) of the supported CSG(s). Figure below depicts the S1 Setup, successful operation.

When the MME cannot accept S1 Setup request, it should respond with a S1 Setup Failure and appropriate cause value. If the S1 Setup Failure message includes Time to Wait IE, the eNB shall wait at least for the indicated time before reinitiating the S1 Setup towards the same MME. If the eNB fails to receive the S1 Setup Response message within certain amount of time configured by S1_SETUP timer, it retransmits the S1 Setup Request again to MME. Note that this S1 management interface is essential for LTE service, there is no retry count. It means that the eNB retransmits S1 Setup Request to the MME unlimitedly until it receives S1 Setup Response successfully from MME. The figure below depicts the S1 Setup, unsuccessful operation.


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S1 Reset When an abnormal situation occurs, S1 interface of all or some UEs can be initialized through reset procedure which runs on S1-C. However, the application level configuration data, which was exchanged by S1 Setup procedure, is not changed. This S1 Reset procedure is executed over S1-C interface which is a control plane interface of S1. The eNB sends the Rest Acknowledge message to the MMEs after receiving the Reset message and then sends the RRC Connection Release message to the target UEs. After that, the UE related resources, which are controlled by the eNB, are released. Figure below depicts the S1 Reset, the MME triggered.

Another example of S1 Reset is when the eNB decides a specific Software or Hardware module is in an abnormal state and unable to provide the normal service, which has resulted in the loss of some or all transaction reference information, it sends the Reset message to the MME. When Samsung eNB determines the cell is not normal any more due to channel card, DSP or RF unit, it sends S1 Reset to the MME. The list of UEs, whose resources should be released, can be specified by MME UE S1AP ID IE or eNB UE S1AP ID IE of the UE-Associated logical S1connection list IE in S1 Reset message. Note that MME UE S1AP ID uniquely identifies a connected UE association among many UE associations within the MME and eNB UE S1AP ID does in the same way within the eNB. Hence, by informing these IDs to the MME or the eNB, the MME or the eNB can easily identify which UEs are impacted by this Reset message and releases them. Figure below depicts the S1 Reset, the eNB triggered.


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If the eNB fails to receive the S1 Reset Acknowledge message within certain amount of time configured by s1Reset timer, it retransmits the S1 Reset message again to the MME upto s1ResetRetryCount times. Unlike Reset by the MME, the eNB doesn‟t send RRC Connection Release to the UE right after Reset if Reset is triggered by the eNB. The reason is that in case of Reset by the eNB, the eNB is in an abnormal state and may not be able to send RRC Connection Release to the corresponding UEs correctly. Hence, instead of sending RRC Connection Release to UEs right away, the eNB relies on each UE‟s failure detection mechanism such as Radio Link Failure (RLF) detection. When the UE detects RLF due to eNB‟s Reset, it tries to send RRC Connection Reestablishment request to the eNB and if the eNB is able to accept this request, the connection continues. If it fails after several times of retries, the UE will release RRC connection by itself and goes to Idle. Later when RRC connection is needed, the UE will send RRC Connection Request to create new RRC connection.

Error Indication When the received message cannot be processed normally and cannot be responded with the appropriate failure message, the eNB or the MME can report this fact to the peer with Error Indication procedure. Currently, Samsung eNB sends Error Indication only when it fails to decode the received messages. It means whenever the eNB decides that it is impossible to parse and interpret the bit stream of the received message, it sends the Error Indication with Cause IE, however, it doesn‟t send Error Indication in case of sematic error or logical errors and so on. For example, if the eNB successfully decodes the received message and it turns out to have a value out of range, the eNB does not send Error Indication and instead, discards or ignores the received IE or message.


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In case the Error Indication procedure is triggered by utilising UE associated signalling the MME UE S1AP ID and the eNB UE S1AP shall be included in the ERROR INDICATION message as below figure. Otherwise, the Error Indication does not include MME UE S1AP ID and the eNB UE S1AP ID. Figure below depicts the error indication, the eNB originated.

Figure below depicts the error indication, the MME originated.

eNB Configuration Update When the eNB wants to update the application level data impacting the UE-related context, the eNB can send the eNB Configuration Update message to the MME with which the eNB has an established S1 connection currently. If the current TAC, eNB Name, or DefaultPagingDRX value set in the PLD is changed during system operation, the eNB includes not only the changed parameter values but also the unchanged parameter values in the eNB Configuration Update message, and sends it to the MMEs. At this time, the eNB must send the message to all MMEs with S1 Setup established. When the eNB Configuration Update message is sent, a timer starts configured by “s1Update” and the eNB expects an eNB Configuration Update Acknowledge message to be received before the timer expires. When the MME cannot accept eNB Configuration Update request, it shall respond with an eNB Configuration Update Failure and appropriate cause value. If the eNB Configuration Update Failure message includes the Time to Wait IE, the eNB shall wait at least for the indicated time before reinitiating the eNB Configuration Update towards the same MME. Both the eNB and the MME shall continue to operate the S1 with their respective configuration data. If the eNB configuration update acknowledge message is not received before the s1Update timer expires, the eNB kills the timer, resends the eNB configuration update message upto S1_UPDATE_RETRY_COUNT times. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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If the supported CSG ID(s) is/are to be updated in CSG or hybrid cell, the whole list of supported CSG IDs, including those that are not to be updated, shall be included in the CSG Id List IE. The MME shall overwrite the whole list of CSG IDs. Figure below depicts the eNB configuration update, successful operation.

The following figure is eNB configuration update, unsuccessful operation.

MME Configuration Update Similar to eNB Configuration Update, when the MME wants to update the application level data impacting the UE-related context, the MME can send the MME Configuration Update message to the eNB with which the eNB has an established S1 connection currently. If the current TAC, CSGID, eNBName, or DefaultPagingDRX value set in the PLD is changed during system operation, the MME includes not only the changed parameter values but also the unchanged parameter values in the MME Configuration Update message, and sends it to the eNBs. At this time, the MME must send the message to all eNBs with S1 Setup established. When the MME Configuration Update message is sent, the MME starts a timer configured by S1AP timer and expects an MME Configuration Update Acknowledge message from the eNB before the timer expires.


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Note that there is no retransmission for MME Configuration Update and thus, if the MME configuration update acknowledge message is not received before the timer expires, the MME stops the timer and MME configuration procedure is stopped and both eNB and MME shall continue to operate the S1 with their respective configuration data. If the eNB sends MME Configuration Update failure, then there might be mismatch in the Relative MME Capacity between the MME and the eNB. In some cases, the eNB selects MME according to the old Relative MME Capacity. Figure below depicts the MME configuration update, successful operation.

Figure below depicts the MME configuration update, unsuccessful operation.

Keep Alive between eNB and MME The SCTP parameter names of the below description is used conceptually. Refer to COM-IP0401 for exact SCTP parameter names of S1 interface. The eNB and the MME can monitor S1-MME connection by exchanging SCTP HEARTBEAT/HEARTBEAT ACK messages defined by SCTP protocol. HEARTBEAT message is periodically transmitted and the period is configured as HEART_BEAT_INTERVAL. When transmitting HEARTBEAT message, the eNB delivers the current time in the Heartbeat Information field, which is also included in the HEARTBEAT ACK message so that the sender and receiver can calculate the Round Trip Time (RTT). Figure below depicts the keep alive between the eNB and the MME, successful operation.


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When HEARTBEAT ACK message is not received, the eNB tries to retransmit HEARTBEAT message periodically. The maximum number of retransmission is configured as NUM_PATH_RE_TX. The period of retransmission is Heartbeat Retransmission Interval in the below figure and calculated as HEART_BEAT_INTERVAL + RTO + RTO*[-0.5, 0.5], where RTO is increased as exponential backoff if the previous HEARTBEAT message is unanswered. The initial, minimum and maximum values are configured as RTO_INITIAL, RTO_MIN and RTO_MAX. When HEARTBEAT ACK is not received after all the retransmission, the link status is considered abnormal. If the MME SCTP connection is considered abnormal, the MME_FAILOVER_TIMER is triggered and the call is not released when the SCTP connection is restored before the timer expiry. However, when the MME_FAILOVER_TIMER expires, all active calls on the SCTP Connection are released and MME_COMMUNICATION_FAIL alarm is generated. Note that eNB does not manage Idle calls. While the MME_COMMUNICATION_FAIL alarm is on, eNB routes new call attempts to another alive MMEs via S1-flex. For example, when there are three MMEs (MME1, MME2 and MME3), the eNB normally maintains three S1 interfaces, one for each MME1, MME2 and MME3 and distributes calls among them. In case S1 interface to the MME1 fails, the eNB routes new call attempts to two remaining MMEs (MME2 and MME3). Figure below depicts the keep alive between eNB and MME, unsuccessful operation.


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In case of S1 setup procedure, the eNB transmits INIT message to establish SCTP association. If it fails to get the response of INIT ACK message, the eNB transmits INIT message once again after 1s. If it is not answered also, the eNB repeats this procedure with the period of CONNECT_INTERVAL until SCTP setup is successful as described in the below figure. Figure below depicts the SCTP setup between the eNB and the MME, unsuccessful operation.


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Path Management between eNB and S-GW According to 3GPP TS 29.281, the eNB and the S-GW can monitor S1-U path using ECHO REQUEST/ECHO RESPONSE messages defined by GTP-U protocol. Here, S1-U Path means a logical connection between an eNB and a SGW. In other words, only one S1-U Path exists between a certain eNB and a certain S-GW even though there may be many S1 bearers between them. Hence, eNB manages only one S1-U path for each S-GW by sending an Echo Request to find out if it is alive. Figure below depicts the path management procedures between the eNB and three S-GW, successful operation. In this case, there are three S1-U paths and for each path, the eNB sends the ECHO REQUEST message to the S-GW periodically and waits for ECHO RESPONSE message.

If the eNB fails to receive the ECHO RESPONSE message, it resends the ECHO REQUEST message up to the configured maximum retransmissions N3_REQUEST. When the eNB fails to receive the ECHO RESPONSE message even after maximum resending, it will release all E-RAB connections with the failed S-GW and triggers MME to release the related calls via S1-Reset procedure. Figure below depicts the keep alive between the eNB and the S-GW, unsuccessful operation.


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How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activation this feature. Activation Procedure Run CHG-MME-CONF to configure MME by adding IP address and to set the status to be Equip and unlock active state of the corresponding MME. Deactivation Procedure Run CHG-MME-CONF to make all MMEs are Not Equipped.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-MME-CONF/CHG-MME-CONF (MME Information) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

MME_INDEX

The index used to access the information. Since there are a total of 16 MMEs that can be connected to an eNB, the index range is 0 to 15.

STATUS

The EQUIP status information on the MME. N_EQUIP: The MME to connect does not exist. EQUIP: The MME to connect exists

ACTIVE_STATE

The state information on the specified MME in operation. Of the MMEs for which the S1 Setup is established, if there is an undesired MME, this parameter value must be changed to Inactive. The default is active. If the STATUS parameter is set to Equip, it is better not to change this parameter value to inactive. Inactive: MME (S1 assigned) is not used. Active: MME (S1 assigned) is used.

IP_VER

The IP address version of the MME. Either IPv4 or IPv6 is assigned.

MME_IPV4

Information on the IPV4 address of the MME. This parameter value is valid only if the IP_VER parameter is set to IPv4. It is not used if the IP_VER parameter is set to IPv6.

MME_IPV6

Information on the IPV6 address of the eNB. This parameter value is valid only if the IP_VER parameter is set to IPv6. It is not used if the IP_VER parameter is set to IPv4.

ADMINISTRATIVE_STATE

The status of the MME link. Locked: A state where active calls connected to the MME are all dropped, and new call connections are not possible. Unlocked: Connection to the MME is normal. Shutting down: A state where active calls connected to the MME are maintained, but new call connections are not possible.

SECONDARY_MME_IPV4

The secondary IP address of the IPv4 type set in the MME node to support the SCTP Multi Homing function. It is valid only if the IP_VER parameter is set to IPv4. *) This is for SCTP multi-homing

SECONDARY_MME_IPV6

The secondary IP address of the IPv6 type set in the MME node to support the SCTP Multi Homing function. It is valid only if the IP_VER parameter is set to IPv6. *) This is for IPv6.

S1_TUNNE_GROUP_ID

This parameter defines IPSec Tunnel Group ID of the MME (valid only if IPsec tunnel group function is supported)

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters Parameter Descriptions of CHG-TIMER-INF/RTRV-TIMER-INF (S1 Management Timer/Count Information) Parameter

Description

S1_SETUP

Waiting duration for S1Setup Response or S1Setup Failure after eNB sends S1Setup Request.(ms)

S1_UPDATE

Waiting duration for eNB Configuration Update Acknowledge or eNB Configuration Update Failure after eNB sends eNB Configuration Update request (ms)

S1_UPDATE_RETRY_COUNT

The retry count for the eNB configuration update procedure when the eNBConfigurationUpdateFailure message is received from the MME or


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Description when time out occurs after sending the eNBConfigurationUpdate message from the eNB.

S1_UPDATE_TIME_TO_WAIT

The TimetoWait value included in MMEConfigurationUpdateFailure transmission.

s1Reset

Retrieve Only (Not Configurable) Waiting duration for S1 Reset Acknowledge after eNB sends S1 Reset Request.(ms).

s1ResetRetryCount

Retrieve Only (Not Configurable) Maximum number of S1 Reset Retransmission. ci_RetryZero: no retransmission ci_RetryOne: 1 retransmission ci_RetryTwo: 2 retransmission ci_RetryThree: 3 retransmission ci_RetryTen: 10 retransmission ci_RetryInfinity: infinite retransmission

Parameter Descriptions of CHG-MME-CONF/RTRV-MME-CONF (MME Information) Parameter

Description

MME_INDEX


STATUS

The EQUIP status information on the MME. N_EQUIP: The MME to connect does not exist. EQUIP: The MME to connect exists.

ACTIVE_STATE


IP_VERr


MME_IPV4


MME_IPV6

Information on the IPV6 address of the eNB. This parameter value is valid only if the IP_VER parameter is set to IPv6. It is not used if the IP_VER parameter is set to IPv4. *) This is for IPv6, which is not included in the current 3UK release.


The status of the MME link. Locked: A state where active calls connected to the MME are all dropped, and new call connections are not possible. Unlocked: Connection to the MME is normal. Shutting down: A state where active calls connected to the MME are maintained, but new call connections are not possible.

SECONDARY_MME_IPV4

The secondary IP address of the IPv4 type set in the MME node to support the SCTP Multi Homing function. It is valid only if the IP_VER parameter is set to IPv4.


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Description *) This is for SCTP multi-homing.

SECONDARY_MME_IPV6


S1_TUNNEL_GROUP_ID

This parameter defines IPSec Tunnel Group ID of the MME

Refer to COM-IP0401 feature for parameter descriptions of CHG-SCTP-PARA /RTRV-SCTP-PARA, CHG-ENBCONN-PARA/RTRV-ENBCONN-PARA.

Parameter Descriptions of CHG-GTP-INF/RTRV-GTP-INF (GTP Information) Parameter

Description

T3_TMR

The interval at which transmission of the ECHO-REQ message is repeated if a response message to ECHO-REQ, which is sent for Keep Alive, is not received. The range is between 0 and 60000 msec. The default is 5000 (5 seconds). This timer runs only if KEEP_ALIVE is set to '1'. (msec)

T3_TMR_LONG

The interval at which the ECHO-REQ message is sent for periodic Keep Alive. The range is between 60000 and 600000 msec. The default is 60000 (60 seconds). This timer runs only if KEEP_ALIVE is set to '1'. (msec)

N3_REQUEST

The maximum retransmission number of the GTP ECHO-REQ message. This timer runs only if KEEP_ALIVE is set to '1'.

KEEP_ALIVE

Whether the GTP ECHO-REQ message at specified intervals (Keep Alive) is sent. 0: The ECHO-REQ message is not sent. 1: The ECHO-REQ message is sent(default).

SNN

Whether the GTP sequence number is used. 0: The GTP sequence number in the eNB is not used. 1: The GTP sequence number in the eNB is used.

ECN

Whether the Explicit Congestion Notification (ECN) function is used. 0: The ECN function in the eNB is not used. 1: The ECN function in the eNB is used.

Parameter Descriptions of RTRV-S1-STS (S1 Status, Retrieval only) Parameter

Description

MME_INDEX

MME Index

MME_ID

MME Id

SCTP_STATE

SCTP state

S1AP_STATE

Interface state

MME_NAME

MME name

IP_VER

MME IP version(IPv4 or IPv6).

MME_IP_V4

MME’s IPV4 address

MME_IP_V6

MME’s IPV6 address


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Parameter Descriptions of CHG-IP-ADDR/CRTE-IP-ADDR/DLT-IPADDR/RTRV-IP-ADDR (IP Address Information) Parameter

Description

IF_NAME

The name of the interface to be set with the IP address. Enter the name of the interface grown. For example, in case of IPsec outer IP with VLAN 100, enter ge_0_0_0.100. In case of IPsec inner IP, it is vpn0, vpn1 or vpn2.

IP_ADDR

The IP address to be set.

IP_PFX_LEN

The prefix length of the IP address determining the network mask. If the network mask is 255.255.255.0, the length is 24.

IP_GET_TYPE

The IP address setting method. STATIC: The user manually enters the IP address. IPSEC: The IP address which is assigned by SeGW when VPN tunnel is setup (RTRV ONLY)

TUNNEL_GROUP_ID

The Group ID of IPSec Tunnel. (RTRV ONLY)

OAM

Attribute of the IP address, whether to use the IP address entered for OAM. False: The IP address is not used for OAM. True: The IP address is used for OAM.

LTE_SIGNAL_S1

Attribute of the IP address. Whether to use the IP address entered for S1 signals. False: The IP address is not used for S1 signals. True: The IP address is used for S1 signals.

LTE_SIGNAL_X2

Attribute of the IP address. Whether to use the IP address entered for X2 signals. False: The IP address is not used for X2 signals. True: The IP address is used for X2 signals.

LTE_BEARER_S1

Attribute of the IP address. Whether to use the IP address entered for S1 bearer. False: The IP address is not used for S1 bearer. True: The IP address is used for S1 bearer.

LTE_BEARER_X2

Attribute of the IP address. Whether to use the IP address entered for X2 bearer. False: The IP address is not used for X2 bearer. True: The IP address is used for X2 bearer.

Parameter Descriptions of CHG-SYS-SIGIP/RTRV-SYS-SIGIP (System Signaling IP Information) Parameter

Description

TUNNEL_GROUP_ID

The Group Id of IPSec Tunnel

SIG_IPVER

The IP version for Signal (RTRV only)

S1_PRI_IPV4_ADDR

The primary IPv4 address for S1 signal. (RTRV only) It is same as IPsec inner IP.

S1_SEC_IPV4_ADDR

The secondary IPv4 address for S1 signal. (RTRV only) *) This is for SCTP multi-homing.

X2_PRI_IPV4_ADDR

The primary IPv4 address for X2 signal. (RTRV only) It is same as IPsec inner IP.

X2_SEC_IPV4_ADDR

The secondary IPv4 address for X2 signal. (RTRV only) *) This is for SCTP multi-homing.


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Description

S1_PRI_IPV6_ADDR

The primary IPv6 address for S1 signal. (RTRV only) *) This is for IPv6, which is not included in the current 3UK release.

S1_SEC_IPV6_ADDR

The secondary IPv6 address for S1 signal. (RTRV only) *) This is for IPv6.

X2_PRI_IPV6_ADDR

The primary IPv6 address for X2 signal. (RTRV only) *) This is for IPv6.

X2_SEC_IPV6_ADDR

The secondary IPv6 address for X2 signal. (RTRV only) *) This is for IPv6.


REFERENCE [1] 3GPP TS36.300, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.412, Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 signalling transport [3] 3GPP TS36.413, Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP) [4] 3GPP TS29.281, General Packet Radio System (GPRS) Tunnelling Protocol User Plane (GTPv1-U) [5] IETF RFC4960, Stream Control Transmission Protocol


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LTE-SW0504, MME Selection and Load Balancing INTRODUCTION The MME Selection and Load Balancing feature allows an eNB to assign an MME for a new attach request, considering load balancing among MMEs in the same pool. An UE that has registered to the MME before will be assigned the same MME for mobility control, which makes the UE use the same IP address that PGW assigned. If the UE has never been assigned the MME, the eNB assigns the UE to one of MMEs considering load among MMEs.

BENEFIT Load is evenly distributed over multiple MMEs according to their relative capacity while the UE can keep the same MME resulting in the same IP address.



Interface & Protocols S1-AP, SCTP

Prerequisite Features LTE-SW0501 (S1 Interface Management)

LIMITATION The eNB supports up to 16 MMEs including both active and standby MMEs. Load balancing between MMEs is based on relative capacity information that the MMEs provide through S1AP interface.

SYSTEM IMPACT Interdependencies between Features Interdependent Feature: LTE-SW5001 Multi-PLMN Support


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This feature is part of LTE-SW5001 Multiple PLMN Support since the eNB selects the most appropriate MME not only based on RMC but also by matching the served PLMN list of MME and selected PLMN by UE. It means that the eNB can support multiple PLMNs by choosing a corresponding MME.

FEATURE DESCRIPTION When the eNB receives an RRC connection request message from the UE, the eNB searches and selects the MME that has served the UE before. The selection is based on S-TMSI information from RRC Connection Requestor message or registered MME information from RRC Connection Setup Complete message. Otherwise, the eNB performs load-based MME selection function for a new call that has no such information in the messages. The eNB selects the MME by well-known weighted round robin method where Relative MME Capacity (RMC) works as weight. The RMC is the relative processing capacity of the MME with respect to the other MMEs in the pool in order to load-balance MMEs within a pool. The MME has responsibility in deciding its capacity(0~255) relative to other MMEs and informs the eNB of its RMC via S1 Setup Response or MME Configuration Update message and then, the eNB stores this value and uses for load balancing. Figure below depicts the MME selection and load balancing procedure for new call.


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1 The UE transmits the S-TMSI information in RRC Connection Request message or the registered MME information in RRC Connection Setup Complete message during RRC connection setup procedure. Note that oThe UE does not provide the registered MME information when it does Power On or it wants to change registered MME. oFor the idle to activation, the registered MME information is provided.

2 The eNB performs MME selection when it receives RRC Connection Request or RRC Connection Setup Complete message from the UE. (If S-TMSI of RRC Connection Request message indicates valid MME, the eNB select this MME. Otherwise, the eNB selects MME based on registered MME from Connection Setup Complete message.) Firstly, the eNB determines whether to allocate a new MME to the UE or find and allocate the MME where the UE had been allocated. If it is necessary to allocate an MME, the eNB selects MME in proportion to the MME capacity to distribute loads. This load balancing among MMEs will be based on Relative MME Capacity Information.

3 After deciding the most proper MME, the eNB transmits INITIAL UE MESSAGE to the specified MME to create UE-associated S1 connection. After this UE-associated S1 connection is created with the MME successfully, all the following signaling messages are sent to this chosen MME.


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How to Activate This section provides the information that you need to configure the feature. Preconditions Ensure that the following conditions are met before enabling this feature: LTE-SW0501, S1 managment feature is enabled. Activation Procedure/Deactivation Procedure This feature runs automatically, and it cannot be disabled.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There are no specific parameters associated with this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MME-CONF/RTRV-MME-CONF (MME Information) Parameter

Description

MME_INDEX


STATUS


ACTIVE_STATE


IP_VER


MME_IPV4


MME_IPV6

Information on the IPV6 address of the eNB. This parameter value is valid only if the IP_VER parameter is set to IPv6. It is not used if the IP_VER parameter is set to IPv4.


The status of the MME link.


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Description Locked: A state where active calls connected to the MME are all dropped, and new call connections are not possible. Unlocked: Connection to the MME is normal. Shutting down: A state where active calls connected to the MME are maintained, but new call connections are not possible.

SECONDARY_MME_IPV4

The secondary IP address of the IPv4 type set in the MME node to support the SCTP Multi Homing function. It is valid only if the IP_VER parameter is set to IPv4. *) This is for SCTP multi-homing

SECONDARY_MME_IPV6


S1_TUNNE_GROUP_ID

This parameter defines IPSec Tunnel Group ID of the MME (valid only if IPsec tunnel group function is supported)


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP) [3] 3GPP TS36.331: Evolved Universal Terrestrial Radio Access Network (EUTRAN); Radio Resource Control (RRC); Protocol specification.


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LTE-SW0505, Random Delayed S1 Setup for Load Distribution INTRODUCTION In case of a MME failure, all the eNodeBs connected to the MME shall release their allocated resources on S1 interface. Upon MME recovery and a successful TNL (Transport Network Layer) association, all the eNodeBs (previously connected to the MME) attempt S1 AP setup simultaneously on the same MME. If the MME cannot accept the setup request due to overload, it may discard the S1 SETUP REQUEST and may not respond to eNodeBs. Hence at the eNodeB, the S1AP setup attempts from multiple eNodeBs have to be randomly delayed and distributed so that there is no overloading at the MME. With this feature, when the MME recovers from failure, the eNodeB calculates a random back off time value and waits for back off timer value then sends the First S1SETUP REQUEST after the successful SCTP association. The eNodeB then starts the random back off timer. In case of no response for random back off timer duration, the eNodeB retransmits S1 SETUP REQUEST. This process repeats until eNB has sent the maximum number of S1 SETUP REQUESTS as configured by the operator. The random back off time value exponentially delays and distributes the arrival of S1 SETUP REQUESTS at the MME from various eNodeBs. This feature need not be enabled if MME is performing S1AP randomization by randomizing TIME TO WAIT IE for different eNodeBs.

BENEFIT MME overload due to simultaneous S1 SETUP REQUEST attempts will be prevented.

eNodeBs attempting to establish S1AP connection are serviced efficiently.

DEPENDENCY AND LIMITATION N/A


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FEATURE DESCRIPTION Normal Startup Operation In the normal mode of startup operation (such as eNB initialization or reset), the eNodeB after sending the first S1 SETUP REQUEST waits for the configured S1_SETUP time (default value is 5 seconds) for S1 SETUP RESPONSE or S1 SETUP FAILURE message from MME. If there is no response from the MME for S1_SETUP time, eNB will retransmit S1 SETUP REQUEST again without applying any additional delay. This operation is performed whether or not Random delay distribution feature is enabled. Random Backoff method during MME Outage and no S1 Setup Response During scenarios such as MME outage and recovery, if Random Delayed S1 Setup for Load Distribution feature is enabled, eNodeB will calculate a random back off time value and start an additional Random Back off wait timer. The eNodeB calculates the Random Back off time in units of miliseconds and as function of eNodeB id,current timestamp, configurable parameters initialBackoffValue and an internal counter setupRetryCount. Following formula is used to calculate the Random Back off time:

The base random number is generated using the eNodeB ID and Time Stamps as the seeds.

The generated random number is further controlled by initialBackoffValue and Setup Retry Count using a modulo operation.

The eNodeB uses setupRetryCount as an internal counter and increases the counter by 1 for every S1 SETUP REQUEST retry attempt with Random back off time.

The Setup retry counter exponentially increases the initial Back Off Value as shown in the formula above.

If the initialBackoffValue is set to zero then randomized back off timer calculation is disabled. The default value of initialBackoffValue parameter is 2 and the range is 0 to 600.

The parameter maxExponentialRange is used to limit Setup Retry Count. The default value of maxExponentialRange is 6 and the range is 0 to 100.

The Setup retry internal counter is used to compare against the maxExponentialRange parameter to determine the allowed number of retry attempts. When Setup retry count reaches maxExponentialRange, Setup retry count resets to 0 again and thus, S1 setup request is sent again with Backoff time calcuated by Setup retry count = 0.


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Upon expiration of this timer, eNB will transmit the S1 Setup Request message. After transmission, eNB will calculate an additional exponential Random backoff wait timer. The eNB will retransmit S1 SETUP REQUEST after expiration of this random back off wait timer. This process is repeated until the max retransmission count is reached. Hence, with this random backoff process, the S1 SETUP REQUESTs arrival at MME is distributed, thereby reducing the chance of overload at MME. In the below Figure, multiple eNodeB are attempting to establish S1AP connection with the MME at the same time, which results in overload at the MME. However, by applying Random Backoff time, the S1 SETUP REQUEST arrival at the MME is distributed.

Random back off time when eNodeB receives S1 SETUP FAILURE during MME Outage During an MME Outage, if the eNodeB receives S1 SETUP FAILURE message without TIME TO WAIT IE, the eNB starts Random Back off timer and wait for random back off time for every re-transmission of S1 SETUP REQUEST. If the eNodeB receives a S1 SETUP FAILURE message with TIME TO WAIT IE, the eNB waits for time specified by TIME TO WAIT IE for further retransmission of S1 SETUP REQUEST and will not use Random Back off timer.


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SYSTEM OPERATION How to Activate This feature can be turned on by set S1_SETUP_BACKOFF_ENABLE value to be 1 using CLI CHG-S1SB-CONF. When turned on, back off operation can be tuned by set MAX_EXPONENTIAL_RANGE, INITIAL_BACKOFF_VALUE.

Key Parameters RTRV-S1SB-CONF/CHG-S1SB-CONF Parameter

Description

S1_SETUP_BACKOFF_ENABLE

This parameter indicates ON/OFF state of S1 SETUP BACKOFF. It has a value of 0 or 1, the default is 1. The 0 means OFF state of S1 SETUP BACKOFF, whereas the 1 means ON. (DEFAULT: 1) 0: OFF 1: ON

MAX_EXPONENTIAL_RANGE

This parameter indicates an incresable range of exponential. The range is 1 to 100, and the default is 6.

INITIAL_BACKOFF_VALUE

This parameter indicates initial backoff used in calculation of backoff time. The range is 0 to 600, and the default is 2.


REFERENCE [1] 3GPP TS 36.413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP)


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LTE-SW0510, Geo Redundancy of MME INTRODUCTION This feature is a part of S1-flex of 3GPP complaint feature, which allows an eNB to interoperate with multiple MMEs for redundancy and high availability. It enables operator to configure a pool of active and standby MMEs. The eNB selects a standby MME for new UEs when all the active MMEs are down.

BENEFIT With this feature, operator can explicitly configure a group of standby MMEs to use only when all the active MMEs are out of service.

From SLR4.5, the eNB selects standby MMEs based on their Relative MME Capacity (RMC) values. Operator can precisely control the frequent selection of certain standby MMEs using their RMC value, thereby increasing the service availability and reducing OPEX.

DEPENDENCY AND LIMITATION Operator must ensure that the following conditions are met when enabling this feature:

Hardware: No impact Device: No impact Interface: MME must provide the relative capacity information through S1AP interface for load balancing between MMEs.

Performance: No impact Capacity: No impact Pre-requisites: No impact

FEATURE DESCRIPTION The S1-flex feature of Samsung enables an eNB to be connected with a pool of active and standby MMEs. The eNB sets up a dedicated S1 connection with the active MME when a UE connects to the network. If all the active MMEs are down, S1-flex provides high availability by allowing the eNB to route UE signaling messages to the standby MME. When the failed MMEs come up and take over the active role, the eNB establishes the new calls with active MMEs and maintains the ongoing calls with standby MME. The Samsung eNB can have connections with up to 16 MMEs belonging to any MME pool. Within the 16 MMEs, the eNB can be eNB 11 of overlapping area and either eNB 10 of MME Pool Area 1 or eNB 12 of MME Pool Area 2, as shown in the below Figure. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The eNB 1 to 11 are connected to MME 1, MME 2, and MME 3 from MME Pool Area 1

The eNB 11 to 16 are connected to MME 4, MME 5, and MME 6 from MME Pool Area 2

The eNB 11 is at Overlapping Area and is active for both the pools Selecting a Standby MME The eNB selects the active MMEs based on their RMC and backup mode configuration. It receives the processing capacity relative to other MMEs from the serving MME through the RMC IE after setting up the dedicated S1-MME connection. Before SLR 3.1, the standby MME method was not included in the feature. In order to support the standby MME configuration, the backup mode parameter is introduced in SLR 3.1. With this parameter, operator can set the backup mode, active or standby, of MME among the connected MMEs. For backward compatibility, the standby MME selection criteria from multiple standby MMEs is enhanced. The below table gives a brief description of each selection criteria introduced from SLR 3.1. Software Release Version

Standby MME Condition

Before SLR 3.1

Before to SLR 3.1 package, Not applicable the Samsung eNB does not support the configuration of standby MME, which implies the eNB cannot continue services if all the active MMEs are down.

In the Figure 1, the eNB 11 considers all six MMEs, MME 1 to 6, as equally active if their RMC value is greater than zero and S1 SCTP connections are active.

SLR 3.1

The eNB decides whether an MME is operating as standby based on either of these conditions: BackupMode = Standby RMC = 0

See section Standby MME Selection in SLR 3.1


Standby MME Selection Criteria

The eNB selects a standby MME based on the round robin method among multiple standby MMEs whose backup mode is configured as standby or RMC value is

Scenario

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Chapter 2 Call Control Software Release Version

Standby MME Condition

Standby MME Selection Criteria equal to zero.

Scenario

SLR 4.5

The eNB decides whether an MME is operating as standby under the conditions: At first, the eNB checks the backup mode of MME is standby If there is no MME that meets the first condition, then the eNB checks the RMC value is zero.

If there are multiple MMEs See section Standby MME Selection in SLR 4.5 that meet the first condition, then the eNB selects the standby MME among them based on its RMC value using round robin approach. If there is no MME that meets the first condition, and are only MMEs with RMC value zero, then the eNB uses the round robin approach to select the standby MME among them.

Selecting a Standby MME in SLR 3.1 Below figure illustrates a scenario where MME 1, MME 2, and MME 3 are configured as active while MME 4, MME 5, and MME 6 as standby at eNB 11. The standby MME is selected among MME 4, MME 5, and MME 6 when all the active MMEs are down.

Similarly, when there is multiple standby MMEs configured, the eNB selects the final MME among the standby MMEs by round robin method. Below figure illustrates a scenario where the eNB 11 selects the final standby MME by round robin approach among the standby MMEs: MME 1, MME 2, and MME 5 if all active MME 3, MME 4, and MME 6 are down.


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Selecting a Standby MME in SLR 4.5 Below figure illustrates a scenario where MME 3, MME 4, and MME 6 are configured as active while MME 1, MME 2, and MME 5 as standby at eNB 11. The standby MME is selected by weighted round robin approach among MME 1, MME 2 and MME 5 when all of MM3, MME4, and MME6 are down.


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Selecting a Standby MME within the MME Pool This feature can be used to configure standby MMEs within the same MME pool. The Figure 5 illustrates a scenario where MME 3 and MME 1 are configured as standby MME at eNB 1 and eNB 10 respectively belonging to same MME Pool Area 1. The eNB1 uses MME 3 only when both MME 1 and MME 2 are down and eNB 10 uses MME 1 only when both MME 2 and MME 3 are down.

Configuring Symmetric Standby MME The Samsung eNB allows configuration of standby MMEs from different MME pools of other geographical zones. With this type of configuration, operator can set the standby MMEs for a pool of active MMEs, which are located at the different zones. Below figure shows a typical scenario where MME Pool 1 and MME Pool 2 serve as standby MMEs for each other symmetrically.


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SYSTEM OPERATION How to Activate In order to configure a specific MME to be a standby MME (for geo redundancy backup-mode), set 'BACKUP_MODE' of the corresponding MME to be 'Standby'.

Key Parameters RTRV-MME-CONF/CHG-MME-CONF (MME INFORMATION) Parameter

Description

MME_INDEX


STATUS


ACTIVE_STATE


BACKUP_MODE

This parameter defines MME's backup mode type.


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP)


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LTE-SW0521, X2 Interface Management INTRODUCTION X2 interface is for direct communication of neighbor eNBs, and used for the handover between eNBs. The X2 handover omits the steps comparing to S1 handover and reduces the total handover time. And it may reduce the HO time exchanging the HO messages instead of exchanging the handover messages between eNBs through the MME depending on backhaul network structure. Also, the X2 interface is for exchanging load information between neighbor eNBs. The X2 interface has control plane and user plane. The control plane connect X2 and AP via the SCTP protocol and make it possible to exchange signaling messages such as X2 handover, load information, and interference information. The user plane uses the GTP tunnels to forward the user data from the source eNB to the target eNB at handover. When a neighbor cell is added to the eNB, the eNB automatically sets up X2 connection with the eNB which includes the target cell. The IP address of target eNB is required to set up X2 connection, use the Automatic Neighbor Relation (ANR) function to learn the steps for getting the IP address. The X2 connection is a SCTP-based between eNBs in the X2 application layer. The X2 interface management function includes all procedure such as setup and monitoring the X2 connection, processing errors, and resetting to manage the X2 connection.

BENEFIT This feature enables operator to manage the signalling associations between eNBs, surveying X2 interface and recovering from errors. Efficient usage of the radio resources with the help of X2 interface management.

DEPENDENCY Required Network Elements Neighbor eNB


Interface & Protocols X2-AP, SCTP, GTP

Prerequisite Features COM-IP0401, SCTP eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LIMITATION Max. 256 X2 connections are supported. X2 based handover between Home eNBs is allowed if no access control at the MME is needed.

SYSTEM IMPACT Interdependencies between Features Intra ANR: ANR also automatically sets up the LTE unique X2 interface between eNBs, primary used for handover.

FEATURE DESCRIPTION X2 AP Setup X2AP setup procedure is for setting up the X2 interface between two eNBs for the first time. Assuming that eNB 1 triggers X2 setup, the following figure shows the X2 AP setup procedures for successful case.

1 The eNB 1 sends its global eNB ID, served cell information, neighbor information, MultibandInfoList, and GU group ID list information to eNB 2 using the X2 Setup Request message. (In the perspective of HeNB, eNB 1 shall contain the CSG ID IE in the X2 SETUP REQUEST message for each CSG or hybrid cell)

2 The eNB 2 receives the X2 Setup Request message and stores the information contained in it in appropriate locations. Then eNB 2 sends its global eNB ID, served cell information, neighbor information, and GU group ID list information to eNB 1 using the X2 Setup Response message. (In the perspective of HeNB, eNB 2 shall contain the CSG ID IE in the X2 SETUP RESPONSE message for each CSG cell or hybrid cell. The eNB receiving the IE shall take this information into account when further deciding whether X2 handover between the source cell and target cell may be performed.) Below figure is X2 AP Setup procedure for unsuccessful case. Samsung eNB #2 sends X2 Setup failures to the eNB #1 if:

X2 setup is not allowed for eNB #1 by operator(NO_X2). X2 setup is not allowed for the primary PLMN of eNB #1 (refer to LTE-SW5012 for details). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1 The eNB 1 receives the X2 setup failure message from eNB #2. 2 The eNB 1 waits as long as Time To Wait as included in the X2 setup failure message and then resends the X2 setup request message to eNB #2.

X2 AP Reset If an abnormal failure occurs with the X2 interface between two interacting eNBs, X2AP Reset procedure is performed to reconcile the resources between the two eNBs. The following figure shows the X2 AP reset procedure. Below figure is X2 AP Reset Procedure.

1 The eNB 1 sends the X2 Reset Request message to eNB 2. 2 The eNB 2 sends the X2 Reset Response message to eNB 1. If there are any procedures which eNB 1 is carrying out via the X2 Interface, eNB 2 stops all of them and performs the Call Release procedure for the call. Samsung eNB sends X2 Reset Request message to its neighbor eNBs when the cell of the eNB is going to be released. If eNB 1 could not receive X2 Reset Response message, it does not resend X2 Reset Request message and there is no further actions

Keep Alive between eNBs The eNB and neighbor eNB can monitor X2 connection by exchanging SCTP HEARTBEAT/HEARTBEAT ACK messages defined by SCTP protocol. HEARTBEAT message is periodically transmitted and the period is configured as HEART_BEAT_INTERVAL. When transmitting HEARTBEAT message, the eNB delivers the current time in the Heartbeat Information field, which is also included in the HEARTBEAT ACK message so that the sender and receiver can calculate the Round Trip Time (RTT).


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In case SCTP connection is disconnected, all active calls will be disconnected. Note that idle mode UEs are not maintained in eNB. Note that HERATBEAT message is defined by SCTP layer.

When HEARTBEAT ACK message is not received, eNB tries to retransmit HEARTBEAT message periodically. The maximum number of retransmission is configured as NUM_PATH_RE_TX. The period of retransmission is Heartbeat Retransmission Interval in the below figure and calculated as HEART_BEAT_INTERVAL + RTO + RTO*[-0.5, 0.5], where RTO is increased as exponential backoff if the previous HEARTBEAT message is unanswered. The initial, minimum and maximum values are configured as RTO_INITIAL, RTO_MIN and RTO_MAX. If HEARTBEAT ACK is not received after all the retransmission, the link status is considered abnormal.


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In case of X2 setup procedure, the eNB transmits INIT message to establish SCTP association. If it fails to get the response of INIT ACK message, eNB retransmits INIT message after 1 sec. If it goes unanswered, the eNB repeats this procedure with the period of CONNECT_INTERVAL until SCTP setup is successful as described in the below figure.

Operator could manage the neighbor eNB link status as follows:

locked: Cancels the relevant X2 handover procedure if there is any current X2 handover call, and blocks a new X2 handover out.

unlocked: Normally processes the X2 Handover. shuttingDown: Normally processes the relevant X2 handover procedure if there is any current X2 handover call, and blocks a new X2 handover out. In order to recover X2 connection, operator can do following actions through LSM.

turn off/on x2 connection with each neighbor eNB manually. send SCTP ABORT message only to neighbor eNBs which current X2 status is enable.

send SCTP ABORT message to all neighbor eNBs regardless of the current X2 interface status.


How to Activate This section provides the information that you need to configure the feature. Preconditions Ensure that the following conditions are met before enabling this feature: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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SCTP connection is established and operational state is normal. Activation Procedure Run CRTE-NBR-ENB or CHG-NBR-ENB and set NO_X2 to False. Deactivation Procedure Run the CHG-NBR-ENB and set NO-X2 to True.

Key Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CRTE-NBR-ENB/DLT-NBR-ENB/CHG-NBRENB/RTRV-NBR-ENB Parameter

Description

NBR_ENB_INDEX

This parameter specifies the index to change the neighbor eNB information required for the operation of the neighbor eNB.

STATUS

This parameter indicates the validity of the neighbor eNB. This parameter must be set accurately since it determines the X2 link and handover execution. N_EQUIP: The information is determined as invalid. EQUIP: The information is determined as valid.

NO_X2

This parameter determines whether to execute X2 link setup with the neighbor eNB. The parameter must be set accurately for X2 link setup to be determined by the setting. False: X2 link setup with the neighbor eNB is executed. True: X2 link setup with the neighbor eNB is not performed.

NO_HO

This parameter determines whether HO is possible with the neighbor eNB. The parameter must be set accurately for Handover to be executed as determined by the setting. False: Handover is done with the neighbor eNB. True: Handover is not done with the neighbor eNB.

ENB_ID

This parameter is the eNB ID of the Neighbor eNB to which the Neighbor Cell belongs. Depending on the Neighbor eNB type, the entry must be made in 20 bits for Macro eNB ID, and 28 bits for Home eNB. This information is used during Handover. The eNB ID of the Neighbor eNB must be entered accurately. If the information does not match, the Handover will not be executed.

ENB_TYPE

This parameter is the eNB type of the neighbor eNB. Macro_eNB: Macro eNB. Home_eNB: Home eNB.

ENB_MCC

This parameter is the PLMN information (MCC) of the eNB where the EUTRAN neighbor cell, located around the eNB, is belonged. Enter 3-digit number whose each digit range is 0-9. The MCC information must be entered accurately.

ENB_MNC

This parameter is the PLMN information (MNC) of the eNB where the EUTRAN neighbor cell, located around the eNB, is belonged. Enter 3-digit or 2-digit number whose each digit range is 0-9.

IP_VER

This parameter is the IP address version indicating the IP address of a neighboring eNB. All neighboring eNB IP version information must be the same.


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Description IPV4: Indicates IPV4 address. IPV6: Indicates IPV6 address.

NBR_ENB_IPV4

This parameter indicates the IP version 4 address of the neighbor eNB. This information is used during X2 Link setup for the SCTP connection setup. Accurately set the information to ensure proper X2 setup.

NBR_ENB_IPV6

This parameter indicates the IP version 6 address of the neighbor eNB. This information is used during X2 Link Setup for the SCTP connection setup. Accurately set the information to ensure proper X2 setup.

SECONDARY_NBR_ENB_IPV4

This parameter indicates the secondary IPv4 address of the neighbor eNB. This information is used during SCTP multi-homing connection setup.

SECONDARY_NBR_NEB_IPV6

This parameter indicates the secondary IPv6 address of the neighbor eNB. This information is used during SCTP multi-homing connection setup.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CRTE-NBR-ENB/DLT-NBR-ENB/CHG-NBRENB/RTRV-NBR-ENB Parameter

Description


This parameter is the neighbor eNB link status information. Note that if the setting is set to Shutdown or Locked, the S1 Handover is executed instead of the X2 Handover. unlocked: Normal operation of the X2 Link state. shuttingDown: Restricts new X2 Handovers but the normal execution of the current X2 Handover in progress. locked: Restricts both of the current X2 Handover in progress and the new X2 Handover.

OWNER_TYPE

This parameter defines how NRT is updated, This filed can be classified Initial NRT/ANR by Server/ANR by UE/Created by User Command/CreatedByUserUI/AnrByTnlReq/AnrByTnlReply/AnrByX2Setup.

REMOTE_FLAG

This parameter indicates whether the neighbor eNB is managed by the same EMS or a different EMS.

CURRENT_X2_RANK

The current X2 rank of corresponding EUTRAN neighbor eNB. Higher value presents higher priority.

PREVIOUS_X2_RANK

The previous X2 rank of corresponding EUTRAN neighbor eNB. Higher value presents higher priority.

NO_REMOVE

It shows whether it is possible to delete Neighbor eNB data.

NO_X2_HO

This parameter is the flag to determine whether X2 or S1 HO will be used between X2 NR only when X2 status is in service. False: X2 HO will be used for X2 NR HO True: X2 HO will not be used. S1 HO will be used X2 NR HO

Parameter Descriptions of CHG-TIMER-INF/RTRV-TIMER-INF Parameter

Description

X2_SETUP

This parameter is the waiting time to receive the X2SetupResponse message or X2SetupFailure message after the X2SetupRequest message is transmitted from the eNB to another eNB. The X2 Setup procedure is a


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Description procedure to exchange the eNB setup information with another eNB that is designated as a neighbor. The eNB setup information includes the Global eND ID information, Global Unique (GU) Group ID List information, Serve Cell information (Physical Cell ID, CellId, TAC, and PLMN), etc. When the X2SetupResponse message is received, the X2 setup is completed and afterwards, if a handover is performed to an eNB where the X2 setup is completed, an X2 handover can be performed. Enough time must be guaranteed until a message is transmitted to another eNB and a response message is received (minimum 100 ms or more).

X2_SETUP_RETRY_COUNT

This parameter is the number of times that the X2SetupRequest procedure should be attempted again when Timeout occurs because the X2SetupFailure message is received or X2SetupResponse message is not received from another eNB after the X2SetupRequest message has been transmitted from the eNB. Zero: The X2SetupRequest re-transmission procedure is not executed. One: The X2SetupRequest re-transmission procedure is executed once. Two: The X2SetupRequest re-transmission procedure is executed twice. Three: The X2SetupRequest re-transmission procedure is executed 3 times. Ten: The X2SetupRequest re-transmission procedure is executed 10 times. Infinity: The X2SetupRequest re-transmission procedure is executed unlimited times.

X2_SETUP_TIME_TO_WAIT

This parameter is the TimetoWait value included in the X2SetupFailure message when the eNB that has received the X2SetupRequest message transmits the X2SetupFailure message. The eNB that has received the TimeToWait information re-transmits the X2SetupRequest message after waiting for the TimeToWait time. 1: Transmits the X2SetupRequest message 1 second after the receipt of the X2SetupFailure. 2: Transmits the X2SetupRequest message 2 seconds after the receipt of the X2SetupFailure. 5: Transmits the X2SetupRequest message 5 seconds after the receipt of the X2SetupFailure. 10: Transmits the X2SetupRequest message 10 seconds after the receipt of the X2SetupFailure. 20: Transmits the X2SetupRequest message 20 seconds after the receipt of the X2SetupFailure. 60: Transmits the X2SetupRequest message 60 seconds after the receipt of the X2SetupFailure.

X2_UPDATE

This parameter is the waiting time to receive the ENBConfigurationUpdateAcknowledge message or ENBConfigurationUpdateFailure message after the ENBConfigurationUpdate message is transmitted from the eNB to another eNB that is designated as a neighbor. The procedure above is a procedure to update the changes of information to another eNB when the Global Unique (GU) Group ID List information and Serve Cell information (Physical Cell ID, CellId, TAC, PLMN) is changed by the operator. Enough time must be guaranteed until a message is transmitted to another eNB and a response message is received (minimum 100 ms or more).

X2_UPDATE_RETRY_COUNT

This parameter is the number of times that the X2 ENBConfigurationUpdate procedure should be attempted again when Timeout occurs because the ENBConfigurationUpdateFailure message is received or ENBConfigurationUpdateAcknowledge message is not received from another eNB after the X2 ENBConfigurationUpdate message has been


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Description transmitted from the eNB. Zero: Does not perform the ENBConfigurationUpdate re-transmission procedure. One: Performs the ENBConfigurationUpdate re-transmission procedure 1 time. Two: Performs the ENBConfigurationUpdate re-transmission procedure 2 times. Three: Performs the ENBConfigurationUpdate re-transmission procedure 3 times. Ten: Performs the ENBConfigurationUpdate re-transmission procedure 10 times. Infinity: Performs the ENBConfigurationUpdate re-transmission procedure infinitely.

X2_UPDATE_TIME_TO_WAIT

This parameter is the TimetoWait value included in the ENBConfigurationUpdateFailure message transmitted by the eNB that has received the ENBConfigurationUpdate message. The eNB that has received the TimeToWait information re-transmits the ENBConfigurationUpdate message after waiting for the TimeToWait time. 1: Transmits the ENBConfigurationUpdate message 1 second after the receipt of the ENBConfigurationUpdateFailure. 2: Transmits the ENBConfigurationUpdate message 2 seconds after the receipt of the ENBConfigurationUpdateFailure. 5: Transmits the ENBConfigurationUpdate message 5 seconds after the receipt of the ENBConfigurationUpdateFailure. 10: Transmits the ENBConfigurationUpdate message 10 seconds after the receipt of the ENBConfigurationUpdateFailure. 20: Transmits the ENBConfigurationUpdate message 20 seconds after the receipt of the ENBConfigurationUpdateFailure. 60: Transmits the ENBConfigurationUpdate message 60 seconds after the receipt of the ENBConfigurationUpdateFailure.

X2_RESET

This parameter is the time waiting to receive the ResetResponse message after an eNB transmits the ResetRequest message to another eNB. The X2 Reset procedure is used to balance resources if there is abnormal failure between neighbor eNBs. An eNB that received X2 Reset performs the procedure of releasing all the call resources in the eNB. Basically, enough time must be guaranteed until a message is transmitted to another eNB and a response message is received (minimum 100ms or more).

X2_RESET_RETRy_COUNT

This parameter is the number of times that the X2 Reset procedure should be attempted again when Timeout occurs because the ResetResponse message is not received from another eNB after the X2 Reset message has been transmitted from the eNB. Zero: The Reset re-transmission procedure is not executed. One: The Reset re-transmission procedure is executed once. Two: The Reset re-transmission procedure is executed twice. Three: The Reset re-transmission procedure is executed 3 times. Ten: The Reset re-transmission procedure is executed 10 times. Infinity: The Reset re-transmission procedure is executed unlimited times.

Parameter Descriptions of RTRV-X2-STS Parameter

Description

NBR_ENB_INDEX

This parameter is the index of the neighbor eNB.


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Description

ENB_MCC

This parameter is the PLMN information (MCC) of the eNB where the EUTRAN neighbor cell, located around the eNB, is belonged. Enter 3-digit number whose each digit range is 0-9.

ENB_MNC

This parameter is the PLMN information (MNC) of the eNB where the EUTRAN neighbor cell, located around the eNB, is belonged. Enter 3-digit or 2-digit number whose each digit range is 0-9.

NBR_ENB_ID

This parameter is the ID of the neighbor eNB.

SCTP_STATE

This parameter is the Stream Control Transmission Protocol (SCTP) status. It is the physical connection status between the eNBs. disable_SD_PlmnTg_UA: shutdown by undecidable PLMN TGID. disable_SD_PlmnVr: shutdown by undecidable PLMN VRID. disable_SD_NoX2: shutdown by NO_X2 setting. disable_SD_Locked: shutdown by administrativeState locked setting. disable_OOS: out of service (all case without above case). enable_INS: in service.

X2AP_STATE

This parameter is the X2AP status. It is the logical connection status between the eNBs. If SCTP is disabled, X2AP cannot be enabled. disable_X2AP_SCTP_OOS: X2Ap status is disabled. Because SCTP status is OOS Out-Of-Service). disable_X2AP_SETUP_TO: X2Ap status is disabled. Because retry count of X2 setup request is over than threshold. disable_X2AP_RESET_TO: X2Ap status is disabled. Because retry count of X2 reset is over than threshold. disable_X2AP_UPDATE_TO: X2Ap status is disabled. Because retry count of X2 update request is over than threshold. disable_X2AP_SETUP_FAIL: X2Ap status is disabled. When X2 setup failure is received and x2 setup retry count was is 0(zero). disable_X2AP_UPDATE_FAIL: X2Ap status is disabled. When X2 update failure is received and x2 update retry count is 0(zero).


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 application protocol (S1AP) [3] 3GPP TS36.423 Evolved Universal Terrestrial Radio Access Network (EUTRAN); X2 application protocol (X2AP)


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LTE-SW3010, PDCP Sublayer Support INTRODUCTION The PDCP Sublayer Support feature provides functions of PDCP sublayer which is one of LTE layer 2 sublayers.

BENEFIT This feature enables basic LTE service including delivery of control/user plane data.

DEPENDENCY None

LIMITATION None


FEATURE DESCRIPTION In LTE system, the layer 2 is split into three sublayers: Medium Access Control (MAC), Radio Link Control (RLC) and Packet Data Convergence Protocol (PDCP). Figure below depicts control plane and user plane protocol stack of LTE system.


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The PDCP sublayer processes Radio Resource Control (RRC) messages in the control plane and Internet Protocol (IP) packets in the user plane. Figure below depicts PDCP layer functional architecture of user plane.

Each radio bearer that uses the PDCP sublayer is configured to have one PDCP entity. Only SRBs/DRBs mapped on DCCH and DTCH type of logical channels can use PDCP sublayer functions. The detailed functions are as follows:

Header compression and decompression of user plane data Transfer of control/user plane data PDCP Sequence number (SN) maintenance Timer based discard of user plane data Discard of duplicates In-sequence delivery of upper layer PDUs at PDCP re-establishment of lower layers for RLC AM

Duplicate detection/elimination of lower layer SDUs at PDCP re-establishment for RLC AM

Ciphering and deciphering of user plane data and control plane data Integrity protection and verification of control plane data


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Type Name

Type Description

Packet Loss Rate

PdcpSduLossRateUL

The calculated average loss rate of uplink SRB Packet that is received in the PDCP

PdcpSduAirIntfAvg

The calculated DL PDCP SDU loss rate.

PdcpSduTotalULNum

The number of UL PDCP SDUs

PdcpSduLossULNum

The number of lost UL PDCP SDUs

PdcpSduTotalDLNum

The number of total DL PDCP SDUs.

PdcpSduLossDLNum

The number of DL PDCP SDUs lost during the collection period. When a RLC ACK message has not been received even after maximum retransmission, the SDU is regarded as a lost DL PDCP SDU. This counter only applies for RLC AM. "0" should be displayed for RLC UM bearers.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.323 Evolved Universal Terrestrial Radio Access (E-UTRA); Packet Data Convergence Protocol (PDCP) specification


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LTE-SW3011, Header Compression ROHCv1 (RTP, UDP, IP) INTRODUCTION The Header Compression ROHCv1 (RTP, UDP, IP) feature supports 3GPP and IETF specified Robust Header Compression (RoHC) algorithm on PDCP layer between eNB and UE. RoHC compresses typical 40 bytes overhead of RTP, UDP, and IP header up to only 3 bytes by placing a compressor before the L2 link, and placing a decompressor after that link. The opposite side decompress, making a new IP/UDP/RTP header just before being delivered to IP layer. The main application for RoHC algorithm is VoLTE, which is a typical RTP/UDP/IP packet.

BENEFIT The eNB and UE can enhance user data throughput by applying RoHC to user data transmitted over the radio link.

When this feature is enabled for VoLTE, the eNB can accommodate more VoLTE users at the same time.

DEPENDENCY UE needs to support RoHC for header compression over the radio link.

LIMITATION This feature supports IPv4 only.


FEATURE DESCRIPTION With this feature, Samsung eNB supports RoHC algorithm on PDCP sublayer. In PDCP sublayer, RoHC compression is only applied to the user plane, and should not be applied to the control plane. Table below outlines the header compression protocol and profiles. Each profile can be applied to each IPv4 and IPv6, but Samsung eNB supports only IPv4 profiles: 0x0000, 0x0001, 0x0002, and 0x0004. Profile Identifier

Usage:

Reference

0x0000

No compression

RFC 4995


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Chapter 2 Call Control Profile Identifier

Usage:

Reference

0x0001

RTP/UDP/IP

RFC 3095, RFC 4815

0x0002

UDP/IP

RFC 3095, RFC 4815

0x0003

ESP/IP

RFC 3095, RFC 4815

0x0004

IP

RFC 3843, RFC 4815

0x0006

TCP/IP

RFC 4996

0x0101

RTP/UDP/IP

RFC 5225

0x0102

UDP/IP

RFC 5225

0x0103

ESP/IP

RFC 5225

0x0104

IP

RFC 5225

Upon connecting to the eNB, the UE shall be able to negotiate with the eNB, RoHC profile information over UE-EUTRA-CAPABILITY message. Each RoHC profile is bearer specific, therefore the operator may set RoHC profile for each QCI through LSM interface. The ROHC context is never transferred during handover. An operator can set Enable/Disable RoHC for each QCI, profile list, and max RoHC Context sessions.

RoHC Architecture and Configuration Figure below depicts the RoHC compressor (transmission side) and decompressor (reception side).

The compression consists of the three states: Initialization and Refresh (IR) state, First-Order (FO) state, and Second-Order (SO) state.

IR state: The compressor has just been created or reset, and full packet headers are sent. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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FO state: The compressor has detected and stored the static fields (such as IP addresses and port numbers) on both sides of the connection. The compressor is also sending dynamic packet field differences in FO state. Thus, FO state is essentially static and pseudo-dynamic compression.

SO state: The compressor is suppressing all dynamic fields such as RTP sequence numbers, and sending only a logical sequence number and partial checksum to cause the other side to predictively generate and verify the headers of the next expected packet. In general, FO state compresses all static fields and most dynamic fields. SO state is compressing all dynamic fields predictively using a sequence number and checksum. When mismatch of the state happens, due to the change of the header information, the compressor in the eNB side begins to transmit full header to synchronize the context state. According to RFC 3095 the ROHC scheme has three modes of operation: the Unidirectional, the Bidirectional Optimistic, and the Bidirectional Reliable mode. In the Unidirectional mode of operation, packets are only sent in one direction: from compressor to decompressor. This mode therefore makes ROHC usable over links where a return path from decompressor to compressor is unavailable or undesirable. The Bidirectional Optimistic mode is similar to the Unidirectional mode, except that a feedback channel is used to send error recovery requests and (optionally) acknowledgments of significant context updates from the decompressor to compressor. The O-mode aims to maximize compression efficiency and sparse usage of the feedback channel. The Bidirectional Reliable mode differs in many ways from the previous two. The most important differences are a more intensive usage of the feedback channel and a stricter logic at both the compressor and the decompressor that prevents loss of context synchronization between compressor and decompressor except for very high residual bit error rates.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-ROHC-INFO and set ROHC_SUPPORT of each QCI as True. Deactivation Procedure Run CHG-ROHC-INFO and set ROHC_SUPPORT of each QCI as False. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameter To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ROHC-INFO/RTRV-ROHC-INFO Parameter

Description

ROHC_SUPPORT

This parameter sets whether to support the RoHC in the PDCP. False: Does not use the RoHC for the QCI. True: Uses the RoHC for the QCI.

Configuration Parameter To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ROHC-INFO/RTRV-ROHC-INFO Parameter

Description

QCI

This parameter is the QoS Class Identifier (QCI). The range is 0-255.The standard QCI defined in the standard document is 1-9. 0 and 10-255 can be used by the operator optionally.

MAX_CONTEXT_SESSION

This parameter sets the maximum number of Active ROHC Contexts that the eNB and the UE can support.

PROFILE0001

This parameter indicates whether to support the ROHC profile0001 (RTP/UDP/IP, RFC3095/4815). False: The QCI does not support profile0001. True: The QCI supports profile0001.

PROFILE0002

This parameter indicates whether to support the ROHC profile0002 (UDP/IP, RFC3095/4815). False: The QCI does not support profile0002. True: The QCI supports profile0002.

PROFILE0003

This parameter indicates whether to support the ROHC profile0003 (ESP/IP, RFC3095/4815). False: The QCI does not support profile0003. True: The QCI supports profile0003.

PROFILE0004

This parameter indicates whether to support the ROHC profile0004 (IP, RFC3095/4815). False: The QCI does not support profile0004. True: The QCI supports profile0004.

PROFILE0006

This parameter indicates whether to support the ROHC profile0006 (TCP/IP, RFC4996). False: The QCI does not support profile0006. True: The QCI supports profile0006.

PROFILE0101

This parameter indicates whether to support the ROHC profile0101 (RTP/UDP/IP, RFC5225). False: The QCI does not support profile0101. True: The QCI supports profile0101.


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Description

PROFILE0102

This parameter indicates whether to support the ROHC profile0102 (UDP/IP, RFC5225). False: The QCI does not support profile0102. True: The QCI supports profile0102.

PROFILE0103

This parameter indicates whether to support the ROHC profile0103 (ESP/IP, RFC5225). False: The QCI does not support profile0103. True: The QCI supports profile0103.

PROFILE0104

This parameter indicates whether to support the ROHC profile0104 (IP, RFC5225). False: The QCI does not support profile0104. True: The QCI supports profile0104.


Type Name

Type Description

CP_PACKET

RoHCDecompFailRate

The RoHC Decompression Failure Rate of PDCP uplink DRB Packet. So the denominator is the total number of received packets; RoHC Decompression Success SDU + RoHC decompression Failure SDU.

RoHCDecompFailCnt

The number of RoHC decompression failed UL PDCP SDUs.

RoHCDecompSuccCnt

The number of RoHC decompression succeeded UL PDCP SDUs.

REFERENCE [1] 3GPP TS36.323 Evolved Universal Terrestrial Radio Access (E-UTRA); Packet Data Convergence Protocol (PDCP) specification [2] IETF RFC3095 RObust Header Compression (ROHC): Framework and four profiles: RTP, UDP, ESP, and umcompressed [3] IETF RFC3759 RObust Header Compression (ROHC): Terminology and Channel Mapping Examples [4] IETF RFC3843 RObust Header Compression (ROHC): A Compression Profile for IP [5] IETF RFC4815 RObust Header Compression (ROHC): Corrections and Clarifications to RFC 3095 [6] IETF RFC4995 RObust Header Compression (ROHC) Framework [7] IETF RFC4996 RObust Header Compression (ROHC): A Profile for TCP/IP (ROHC-TCP) [8] IETF RFC5225 RObust Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP-Lite


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LTE-SW3052, Ciphering: Null/SNOW3G/AES INTRODUCTION Three algorithms 128-EEA1/128-EIA1 (SNOW-3G based algorithm), 128EEA2/128-EIA2 (AES based algorithm), and 128-EEA0/EIA0 (NULL) are defined in LTE security architecture for confidentiality and integrity protection. The confidentiality algorithms, 128-EEA1 and 128-EEA2, are used to encrypt/decrypt blocks of data using confidentiality key CK. The integrity algorithms, 128-EIA1 and 128-EIA2 compute a 32-bit MAC (Message Authentication Code) of a given input message using integrity key IK and MAC will be appended to the message. EEA0 and EIA0 provide no security.

BENEFIT Prevents UE tracking based on cell level measurement reports. Supports privacy protection for user information.


FEATURE DESCRIPTION The input parameters to the integrity algorithm are a 128-bit integrity key named KEY, a 32-bit COUNT, a 5-bit bearer identity called BEARER, the 1-bit direction of the transmission (that is, DIRECTION), and the message itself (that is,MESSAGE). The DIRECTION bit shall be 0 for uplink and 1 for downlink. The bit length of the MESSAGE is LENGTH. The following figure illustrates the use of the integrity algorithm EIA to authenticate the integrity of messages.


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The input parameters to the ciphering algorithm are a128-bit cipher key named KEY, a 32-bit COUNT, a 5-bit bearer identity BEARER, the 1-bit direction of the transmission i.e. DIRECTION, and the length of the keystream required i.e. LENGTH. The DISRECTION bit shall be 0 for uplink and 1 for downlink. The following figure illustrates the use of the cipher algorithm EEA to encrypt the messages.

Integrity protection applies to control-plane messages whereas ciphering covers all radio bearers including the control plane and user plane. In order to ensure integrity for UE-eNB communications, the integrity value (MAC-I) calculated and sent by one party is compared with the recalculated value of the other party after receiving the message. If any discrepancy is found, the message is deemed altered during transmission, and is discarded. The detailed procedure is explained below:

1 The RRC block of the eNB acknowledges the Initial Context Setup Request and selects an AS algorithm.

2 The integrity/ciphering algorithm preferred by the eNB is specified by a system parameter. The algorithm identical to the one sent via the UE Security Capabilities IE of the Initial Context Setup Request is selected. The RRC block derives from KeNB, Krrc_int, Krrc_enc, and Kup_enc.

3 The RRC block sends the selected algorithm, Krrc_int, Krrc_enc, and Kup_enc to the PDCP block. The integrity protection should be applied to the subsequent RRC message.

4 After receiving acknowledgement from the PDCP, the RRC block sends the SecurityModeCommand message to the UE, along with the selected algorithm.

5 After receiving the Security Mode Complete message from the UE, the RRC block controls the PDCP block to apply ciphering for SRB #1. The PDCP block then applies integrity/ciphering protection to all subsequent radio bearers.


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SYSTEM OPERATION How to Activate The algorithm applied to ciphering and integrity may be selected through the CHG-SECU-INF command.

Key Parameters CHG-SECU-INF/RTRV-SECU-INF Paramter

Description

DB_INDEX

Tuple index

INTEGRITY_EA_PRIOR

The integrity protection algorithm supported by the eNB. EIA0: NULL EIA1: SNOW 3G EIA2: AES

CIPHERING_EA_PRIOR

The ciphering algorithm supported by the eNB. EIA0: NULL EIA1: SNOW 3G EIA2: AES


REFERENCE [1] 3GPP TS 33.401 3GPP System Architecture Evolution (SAE); Security architecture [2] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol Specification [3] 3GPP TS 36.323 Evolved Universal Terrestrial Radio Access (E-UTRA); Packet Data Convergence Protocol (PDCP) specification


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LTE-SW4101, Capacity based Call Admission Control INTRODUCTION Call Admission Control (CAC) function is basically enabled to efficiently use the limited radio resources, to guarantee the quality of user service even in case of congestion, and to protect eNB system from being overloaded. Capacity-based CAC makes a decision based on the capacity that operator configures in advance.

BENEFIT By limiting the maximum number UEs or bearers per cell and per eNB, considering radio and backhaul bandwidth, operator can control the minimum QoS level provided for UEs.

Operator can protect the system from being shutdown due to overload or congestion.

DEPENDENCY None

LIMITATION None

SYSTEM IMPACT Interdependencies between features LTE-SW4102 QoS based Call Admission Control and LTE-SW4106 Call Admission Control per QCI operates after Capacity based CAC is passed, if they are activated.


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FEATURE DESCRIPTION Functional Architecture There are three call admission control functionalities: Capacity-based Call Admission Control (CAC), QoS-based Call Admission Control and Pre-emption. For other two CAC features, refer to the LTE-SW4102 (QoS based Call Admission Control) and the LTE-SW4103 (Preemption). Figure below depicts the overall call admission control procedure.

This feature allows an incoming call or bearer as long as the total number of calls/bearers does not exceed the pre-configured thresholds per cell and the eNB. There exist three kinds of thresholds: threshold for normal, threshold for emergency and handover user, and the maximum. These thresholds per the eNB can be depicted as the figure below. Normal users can be allowed up to NOR_ENB_CALL_COUNT per eNB. Emergency and HO users can be allowed up to EM_HO_ENB_CALL_COUNT per eNB. These thresholds can be configured for CAC via LSM by using CALL_CAC_THRESH_FOR_NORMAL and CALL_CAC_THRESH_FOR_EMER_HO as follows:

NOR_ENB_CALL_COUNT = MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_NORMAL for the corresponding eNB,

EM_HO_ENB_CALL_COUNT = MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_EMER_HO for the corresponding eNB.. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Also, there exist similar thresholds per cell as the figure below. Normal users can be allowed up to NOR_CELL_CALL_COUNT per cell. Emergency and HO users can be allowed up to EM_HO_CELL_CALL_COUNT per cell. These thresholds can be configured for CAC via LSM by using CALL_CAC_THRESH_FOR_NORMAL and CALL_CAC_THRESH_FOR_EMER_HO as follows:

NOR_CELL_CALL_COUNT = MAX_CELL_CALL_COUNT * CALL_CAC_THRESH_FOR_NORMAL for the corresponding cell,

EM_HO_CELL_CALL_COUNT = MAX_CELL_CALL_COUNT * CALL_CAC_THRESH_FOR_EMER_HO for the corresponding cell. In addition, there is another threshold for generating a notification if the number of admitted UEs in the cell exceeds the threshold.

For radio bearer, capacity based CAC applies similar concept per cell as depicted in the figure below. Bearers for normal users can be allowed up to NOR_DRB_CALL_COUNT per cell. Bearers for emergency and HO users can be allowed up to EM_HO_DRB_COUNT per cell. Theses thresholds can be configured for CAC by using DRB_CAC_THRESH_FOR_NORMAL and DRB_CAC_THRESH_FOR_EMER_HO as follows:

NOR_DRB_COUNT = MAX_DRB_COUNT * DRB_CAC_THRESH_FOR_NORMAL for the corresponding cell,

EM_HO_DRB_COUNT = MAX_DRB_COUNT * DRB_CAC_THRESH_FOR_EMER_HO for the corresponding cell. In addition, there is another threshold for generating a notification if the number of admitted bearers in the cell exceeds the threshold.


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Related Parameters For the capacity, operator should consider the hardware platform and radio resources, such as radio bandwidth, the number of channel card, and QoS level. Table below outlines an example of system parameter configuration for this feature in case of 10 MHz bandwidth and the maximum values. These values can be varied with different channel card and system bandwidth. System Parameters

Criteria (10 MHz BW)

Decision

MaxUeCELL (= MAX_CELL_CALL_COUNT)

600

Current # of UEs of the cell < MaxUeCELL

MaxUeENB (= MAX_ENB_CALL_COUNT)

1800

Current # of UEs of the eNB < MaxUeENB

MaxRbUE

8

Current # of bearers of the UE < MaxRbUE

MaxRbCELL (= MAX_DRB_COUNT)

1200

Current # of bearers of the cell < MacRbCELL

In this context, number of active UE's is equal to the number of active RRC Connections. For the number of bearers, GBR bearers and Non-GBR bearers are counted all together. Maximum number of radio bearers per UE, which counts only data radio bearers excluding signaling radio bearers, is limited by MAC layer protocol specification (3GPP TS 36.321) and it is not configurable by operator.

Operation Details This section describes this feature's operation in each call procedure:


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During RRC Connection Establishment

1 During the RRC connection establishment, the eNB capacity-based CAC operates per call. The procedure starts when the RRC connection request message is received from the UE.

2 The eNB capacity-based CAC procedure is initiated. Firstly, the CAC operates at eNB the level. If the eNB level CAC is passed, cell level CAC proceeds. Detailed procedure is described as follows: oeNB level CAC If the attempted RRC Connection is for normal user, NOR_ENB_CALL_COUNT is applied for the threshold. If the current number of UEs in the eNB is less than NOR_ENB_CALL_COUNT, the eNB level CAC for the RRC Connection is passed. Otherwise, the call is rejected. If the attempted RRC Connection is for an emergency user, EM_HO_ENB_CALL_COUNT is applied for the threshold. If the current number of UEs in the eNB is less than EM_HO_ENB_CALL_COUNT, eNB level CAC for the RRC Connection is passed. Otherwise, the call is rejected. ocell level CAC If the attempted RRC Connection is for normal user, NOR_CELL_CALL_COUNT is applied for the threshold. If the current number of UEs in the cell is less than NOR_CELL_CALL_COUNT, eNB level CAC for the RRC Connection is passed. Otherwise, the call is rejected. If the attempted RRC Connection is for an emergency user, EM_HO_CELL_CALL_COUNT is applied for the threshold. If the current number of UEs in the cell is less than EM_HO_CELL_CALL_COUNT, eNB level CAC for the RRC Connection is passed. Otherwise, the call is rejected.

3 If the call is rejected and RRCConnectionReject is sent to the UE, depriotisationReq IE can be populated according to the configuration. RRCConnectionReject-v1130-IEs ::= SEQUENCE { eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 2 Call Control deprioritisationReq-r11 SEQUENCE { deprioritisationType-r11 ENUMERATED {frequency, e-utra}, deprioritisationTimer-r11 ENUMERATED {min5, min10, min15, min30} } OPTIONAL, -- Need ON nonCriticalExtension SEQUENCE {} OPTIONAL}

4 If both eNB and cell level CAC is passed, RRC connection establishment is initiated by transmitting the RRC connection setup message to the UE. If the call is rejected and the call type is emergency call, the longest call among active calls in the cell is released. For a normal call, the RRC connection release message is transmitted to the UE and the call is released.

5 The UE transmits the RRC Connection Setup Complete message. 6 The eNB sends the MME Initial UE message. During E-RAB Setup

1) fter the RRC establishment, the eNB capacity-based CAC operates by receiving the initial context setup request or E-RAB setup/modify request message from the MME for the default radio bearer and dedicated radio bearer (DRB) setup. 2) The eNB capacity-based CAC runs per E-RAB. oIf the attempted bearer is for normal user, NOR_DRB_COUNT is applied for the threshold. If the current number of bearers in the cell is less than NOR_DRB_COUNT,the call is admitted. Otherwise, the call is rejected. oIf the attempted bearer is for emergency user, EM_HO_DRB_COUNT is applied for the threshold. If the current number of bearers in the cell is less than EM_HO_DRB_COUNT, the call is admitted. Otherwise, the call is rejected. 3~4) If the E-RAB is successfully admitted, the RRC connection reconfiguration message is transmitted to the UE to initiate an E-RAB (DRB) establishment. If the call is rejected, whether to admit the E-RAB is determined in interoperation with the preemption function per E-RAB (DRB) to control the call flow. In the case that not all bearers can be admitted, bearers can be handled as follows according to the configuration: oa partial success per E-RAB is ignored (whole bearers are rejected) if a partial success flag is not set. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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opossible E-RABs are admitted if a partial success flag is set. 5) eNB sends the MME E-RAB setup message. During Intra-eNB Handover

1 The eNB receives a measurement report from a UE. 2 When cell change take places within the same eNB, the eNB capacity-based CAC operates to control intra-eNB handover call admission.

3 The eNB capacity-based CAC is initiated based on a call. If the current number of UEs in the cell is less than EM_HO_ENB_CALL_COUNT, the call is admitted. Otherwise, the call is rejected. If the current number of bearers in the cell is less than EM_HO_DRB_COUNT, the call is admitted. Otherwise, the call is rejected.

4 If the call is admitted, the RRC connection reconfiguration message is transmitted to the UE to initiate the intra-eNB handover. If the call is rejected, whether to admit the E-RAB is determined in interoperation with the preemption function per E-RAB (DRB) to control the call flow (a partial success per E-RAB is ignored).

5 The UE transmits RRC connection reconfiguration complete message.


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During Inter-eNB Handover

1) The eNB receives a measurement report from a UE. 2) The source eNB determines HO and sends the target eNBs a Handover Request message. 3) To control inter-eNB handover call admission, the eNB capacity-based CAC operates by using the E-RAB Level QoS parameter included in the Handover Request message received. The eNB capacity-based CAC is initiated based on a call. If the current number of UEs in the cell is less than EM_HO_ENB_CALL_COUNT, the call is admitted. Otherwise, the call is rejected. If the current number of bearers in the cell is less than EM_HO_DRB_COUNT, the call is admitted. Otherwise, the call is rejected. 4) If the call is admitted, the Handover Request Acknowledge message is transmitted to the source eNB to initiate the inter-eNB handover. If the call is rejected, whether to admit the E-RAB is determined in interoperation with the preemption function per E-RAB (DRB) to control the call flow. In the case that not all bearers can be admitted, bearers can be handled as follows according to the configuration: oa partial success per E-RAB is ignored (whole bearers are rejected) if a partial success flag is not set. opossible E-RABs are admitted if a partial success flag is set. 5~6) The source eNB transmits the RRC connection reconfiguration message to the UE and performs SN Status Transfer. 8~10) After path switch procedure, the target eNB sends Release Request the source eNB. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Run CHG-ENB-CAC and set CALL_COUNT_CAC_USAGE to use. Run CHG-CELL-CAC and set CELL_COUNT_CAC_USAGE to use. Deactivation Procedure To deactivate this feature, do the following:

Run CHG-ENB-CAC and set CALL_COUNT_CAC_USAGE to no_use. Run CHG-CELL-CAC and set CELL_COUNT_CAC_USAGE to no_use. Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ENB-CAC/RTRV-ENB-CAC, CHG-CELLCAC/RTRV-CELL-CAC Parameter

Description

CALL_COUNT_CAC_USAGE

Whether to execute the Capacity-based Call Admission Control (CAC) function per cell. ci_no_use: The capacity-based CAC function per base station is not performed. ci_use: The capacity-based CAC function per base station is performed.

CELL_COUNT_CAC_USAGE

Whether to execute the call count-based CAC function, which is one of the capacitybased Call Admission Control (CAC) functions per cell. ci_no_use: The capacity-based CAC function per cell is not performed. ci_use: The capacity-based CAC function per cell is performed.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ENB-CAC/RTRV-ENB-CAC eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

DB_INDEX

The index to be changed or retrieved.



MAX_ENB_CALL_COUNT

The limit for capacity based CAC (call admission control) at the eNB level. The number of calls that can be allowed by the eNB.

CALL_CAC_THRESH_FOR_ NORMAL

The percentage of the allowable calls to the total normal calls. When a normal call is requested, if the number of connected calls exceeds MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_NORMAL, the Capacity-based CAC Fail is generated.

CALL_CAC_THRESH_FOR_E MER_HO

Emergency call availability of total handover calls in percentage. When a normal call is requested, if the number of connected calls exceeds MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_EMER_HO, the Capacity-based CAC Fail is generated.

CHECK_UE_ID_USAGE

Whether to execute the SAE Temporary Mobile Station Identifier (S-TMSI) Duplication Check function for a new call. ci_no_use: The S-TMSI Duplication Check function is not performed. ci_use: The S-TMSI Duplication Check function is performed. If a call is found as a duplicate, the existing call is released and the new call is accommodated.

highPriorityAccessType

This parameter determines the type of a highpriorityaccess call. If the type is normalType, handles the highpriorityaccess as a normal call. If the type is emergencyType, handles the highpriorityaccess as an emergency call.

emergencyDuration

This parameter is the time taken to recognize a UE that includes the s-TMSI in paging as an emergency call. If the s-TMSI included in the paging message comes in with a call within the EMERGENCY_DURATION time, it is handled as an emergency call.

cacNotificationUsage

Control on/off of the feature to send a notification to LSM when the calls or DRBs exceed the call or drb Notification Threshold set by RTRV/CHG-CELLCAC.

cacNotificationMonitoringPerio d

Decide whether to generate a notification again after the period from the moment when a call or DRB CAC notification was generated as the calls or DRBs were created more than the set Notification threshold.

Parameter Descriptions of CHG-CELL-CAC/RTRV-CELL-CAC Parameter

Description

cellNum


cellCountCacUsage

This parameter indicates whether to perform call count based CAC among the cell-based capacity based Call Admission Control (CAC) functions. no_use: Does not perform the capacity based CAC function per cell. use: Performs the capacity based CAC function per cell.

maxCallCount

This parameter indicates the maximum call count in a Cell. This value is used


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Description during Capacity based CAC (Call Admission Control) per cell. The maximum call count is recommended based on system performance and RRH bandwidth. Be sure not to increase more than contracted system capacity per cell.

callCacThreshForNormal

This parameter is capacity based CAC threshold for normal calls (e.g. Attach and Idle to Active) of the cell. If the number of connected calls exceeds MAX_CALL_COUNT * CALL_CAC_THRESH_ FOR_NORMAL when a normal call is requested, the capacity based CAC failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to be failed, and some resources may be idled and wasted.

callCacThreshForEmer

This parameter is the capacity based CAC threshold for emergency calls of the cell. If the number of connected calls exceeds MAX_CALL_COUNT * CALL_CAC_THRESH_FOR_EMER when an emergency is requested, a capacity based CAC failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to fail, and some resources may be idled and wasted.

callCacThreshForHo

This parameter is the capacity based CAC threshold for for incoming handover call without emergency priority. If the number of connected calls exceeds MAX_CALL_COUNT * CALL_CAC_THRESH_FOR_HO when an incoming handover call is requested, a capacity based CAC failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to fail, and some resources may be idled and wasted.

callCacThreshForMoSig

This parameter is the capacity based CAC threshold for Mobile Originating Signalling calls of the cell. If the number of connected calls exceeds MAX_CALL_COUNT * CALL_CAC_THRESH_FOR_MO_SIG when a incoming call with establishment cause = mo_Signalling call is requested, a capacity based CAC failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to fail, and some resources may be idled and wasted.

callCacThreshForMtAccess

This parameter is the capacity based CAC threshold for Mobile Terminating Access calls of the cell. If the number of connected calls exceeds MAX_CALL_COUNT * CALL_CAC_THRESH_FOR_MT_ACCESS when a incoming call with establishment cause = mt-Access call is requested, a capacity based CAC failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to fail, and some resources may be idled and wasted.

drbCountCacUsage

This parameter indicates whether to perform E-UTRAN Radio Access Bearer (E-RAB) based CAC among the capacity based CAC per cell. no_use: Does not perform the E-RAB number based CAC per cell. use: Performs the E-RAB number based CAC per cell.

maxDrbCount

This parameter is the maximum number of EUTRAN radio access bearer (ERAB) used by capacity based call admission control(CAC) per cell. The DRB count within the cell cannot exceed this value. Actually applicable number limit is determined through a calculation using


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Description DRB_CAC_THRESH_FOR_NORMAL/DRB_CAC_THRESH_FOR_EMER_HO.

drbCacThreshForNormal

This parameter is acceptable percentage of normal calls. If the number of connected calls exceeds MAX_DRB_COUNT * DRB_CAC_THRESH_FOR_NORMAL when a normal call is requested, the Capacity based CAC Failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to be failed, and some resources may be idled and wasted.

drbCacThreshForEmerHo

This parameter is acceptable percentage of emergency calls and handover calls. If the number of connected calls exceeds MAX_DRB_COUNT * DRB_CAC_THRESH_FOR_EMER_HO when a normal call is requested, the Capacity based CAC Failure is generated. If this parameter is too high, the system load after CAC is probably too high, which results in system congestion. If it is too low, the call requests are more likely to be failed, and some resources may be idled and wasted.

qosCacOption

This parameter indicates whether to perform the QoS based CAC function per cell. no_use: Does not perform the QoS based CAC function per cell. use: Performs the QoS based CAC function per cell.

qosPolicyOption

This parameter is the policy for a newly requested GRB bearer when the QoS based CAC function is performed per cell. Option0: PRB usage is calculated based on the resource type (GBR, nonGBR) of the QCI to perform CAC and all the non-GBRs are accepted. Option1: PRB usage is calculated based on the priority of the QCI to perform CAC and all the non-GBRs are accepted.

prbReportPeriod

This parameter is the Physical Resource Block (PRB) report interval for QoS CAC per cell and the unit is second. If QOS_CAC_OPTION is use, this parameter value is transmitted to the MAC layer and the PRB report is transmitted at specified intervals.

estimationOpt

This parameter is the method for calculating the expected Physical Resource Block (PRB) usage. Available in Auto or Manual. Expected PRB is the PRB usage that is expected to increase when a bearer request is received and the applicable bearer is accepted. Auto: Calculates using the specified algorithm. Manual: Calculates using the unitUsageManual value that is set by executing the CHG-QCACQ-PARA command.

preemptionFlag

This parameter indicates whether to perform the preemption function per cell. no_use: Does not perform the preemption function per cell. use: Performs the preemption function per cell.

bhBwCacUsage

This parameter indicates whether to perform the backhaul based CAC function per cell. no_use: Backhaul based CAC functionis not executed. use: Backhaul based CAC is executed. If this parameter is no_use, the backhaul load is probably too high, which results in backhaul congestion.

bhBwCacOption

This parameter is the policy used when the backhaul based CAC function is performed per cell. QCI_only: Performs only CAC function based on QCI of QoS. ServiceGroup_only: Performs only the service group based CAC function. Both_QCI_ServiceGroup: Performs both the QCI (QoS Class Identifier) based


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Description CAC and service group based CAC functions.

qciDrbCacUsage

This parameter indicates whether to perform the QCI DRB CAC function per cell. no_use: Does not perform the function. use: Performs the function.

lBRedirectionUsage

Whether to use Load based Redirection at CAC no_use: Load based Redirection at CAC is not used. use: Load based Redirection at CAC is not used.

adaptiveSharingUsage

Whether to use Adaptive RAN sharing no_use: Load based Redirection at CAC is not used. use: Load based Redirection at CAC is not used.

rsPreemptionOption

The policy of Ran Sharing preemption. overUsingPLMNfirst: For a Ran sharing, PLMN is selected based on overusing PLMN. Then PLMN is selected based on the lowest ARP. lowestARPfirst: For a Ran sharing, PLMN is selected based on the lowest ARP. Then PLMN is selected based on overusing PLMN.

maxCaCallCount

This parameter is the Carrier Aggregation (CA) call count that the cell can accept.

reservedUeCount

This parameter defines the reservation UE count set for the emergency call or priority calls.

lowCallRelOption

When doing CAC about the new emergency Call, Determine the operation method releasing the already attached normal call. (If there is no Normal call among the existing call at all, the new emergency call reception is impossible.) LongestCall: Release UE with the Longest Call base. ArpBased: Release UE with ARP base. No_use: Release is not performed although the Normal Call remains.

emergencyArpPriority

This parameter defines priority of emergency call or priority call.

callCacNotificationThreshold

Call CAC notification is generated when the number of UEs attached to the cell/maxCallCount of the cell exceeds the threshold while CAC Notification is on.

drbCacNotificationThreshold

Drb CAC notification is generated when the number of DRBs set in the cell/ maxDrbCount of the cell exceeds the threshold while CAC Notification is on.

partialCacUsage

It is a parameter to set whether to support Partial CAC in the eNB. If the parameter is set to ‘Use’, it operates in a way that as many bearers as possible are accepted even if the available resources are insufficient when multiple bearers are requested for a new call.


REFERENCE [1] 3GPP TS36.300, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


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LTE-SW4102, QoS based Call Admission Control INTRODUCTION CAC function is basically enabled to efficiently use the limited radio resources, to guarantee the quality of user service even in case of congestion, to protect eNB system from being overloaded. QoS based Call Admission Control admits a new GBR bearer only when the eNB can support the required bit rate.

BENEFIT Operator can provide QoS guaranteed service to UEs. Operator can configure how much resources (PRB, backhaul bandwidth, number of GBR bearers) can be used for GBR services.

Operator can configure the maximum number of GBR bearers per cell.

DEPENDENCY Required Network Elements: MME, this feature has effect when MME requests GBR bearers.

LIMITATION None

SYSTEM IMPACT Interdependencies between features QoS based CAC operates with Capacity based CAC.

FEATURE DESCRIPTION Functional Architecture There are three call admission control functionalities: Capacity-based Call Admission Control (CAC), QoS-based Call Admission Control and Pre-emption. For other two CAC features, refer to the LTE-SW4101 (Capacity based Call Admission Control) and the LTE-SW4103 (Pre-emption). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Figure below depicts the overall call admission control procedure.

This feature admits a new GBR bearer only when it is expected to achieve its guaranteed bit rate requirement under the radio condition of that time. Additional admission of a new GBR bearer must not degrade the QoS level of existing GBR bearers. For this, the eNB monitors the PRB usage and backhaul bandwidth utilization that exisiting GBR bearers are consuming. The eNB makes an admission decision based on these resources utilizations of that time and the QoS level required by the new GBR bearer. Practically, GBR bearers are not likely to consume all the reserved resource as much as the guaranteed bit rate required. Therefore, the estimation of expected throughput of the new GBR bearer QCI is computed based on the actual average throughput of the existing GBR bearers with the same QCI. This allows the eNB to accommodate more GBR bearers. Note that GBR bearers with the same QCI are assumed to use the same service and to consume the similar level of throughput. This feature applies only to GBR bearers. Non-GBR bearers are always allowed as long as the total number bearers per UE and per cell do not exceed the maximum limit, which is not to hinder a UE‟s access to the network because it must establish at least one default non-GBR bearer to attach to the network. As the eNB allows more GBR bearers, less resource can be allocated to non-GBR bearers. It will degrade quality of user experience of the UEs who have non-GBR bearers. To sustain a certain level of service quality for non-GBR services, operator can limit the amount of resources that can be allocated to GBR bearers or the total number of UEs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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For this, operator can configure following system parameters. The eNB allows GBR bearers within the amount of resources configured by operator.

The amount of PRBs that can be allocated to GBR bearers The amount of backhaul bandwidth that can be allocated to GBR bearers The maximum number of GBR bearers (SLR3.0) Operation Details RRC Connection Setup The QoS based CAC is not used in RRC connection setup procedures but capacity based CAC is used. Figure below depicts the E-RAB based setup subjected to capacity and QoS based CAC.

1) After the RRC Establishment procedure, the Initial Context Setup Request message or the E-RAB Setup/Modify Request message is received from the MME to set up the default radio bearer and the dedicated radio bearer (hereafter, DRB). Then, the eNB capacity-based CAC and the QoS-based CAC are performed sequentially to determine whether to admit the call. 2) The eNB capacity-based CAC (SW4101) is initiated per E-RAB. 3) When the E-RAB has the GBR, the QoS-based CAC is initiated. oIf the PRB usage of the cell satisfies CurrentGbrPrbUsage + ExpectedPrbUsage < MaxGbrPrbUsage, the call is admitted. If not, the call is rejected. An estimated PRB usage for the GBR bearer is accumulated to currentGbrPrbUsage usage if the GBR bearer is requested and admitted before currentGbrPrbUsage usage is updated. oIf the Backhaul BW satisfies CurrentGbrBwUsage + ExpectedBw < MaxGbrBw, the call is admitted. If not, the call is rejected. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oIf admission constrol based on packet delays of existing GBR bearers is activated and the estimated packet delays of existing GBR bearers are greater than threshold, the call is reject. If not, the call is admitted oIf the E-RAB is admitted, the RRC Connection Reconfiguration message is transmitted to the UE to perform the E-RAB (DRB) Establishment procedure. If a call is rejected, the CAC function determines whether to admit E-RAB by interworking with the preemption function per E-RAB (DRB) to control the flow of each call. (Partial success per E-RAB is not considered.) 4~5) If the E-RAB is successfully admitted, the RRC connection reconfiguration message is transmitted to the UE to initiate an E-RAB (DRB) establishment. If the call is rejected, whether to admit the E-RAB is determined in interoperation with the preemption function per E-RAB (DRB) to control the call flow (a partial success per E-RAB is ignored). 6) eNB sends the MME E-RAB setup message Intra-eNB Handover Figure below depicts the Intra-eNB Handover subject to Capacity and QoS based CAC.

1) The eNB receives a measurement report from a UE. 2~3) The source eNB determines the handover and capacity based CAC is performed. 4) When the E-RAB has the GBR, the QoS-based CAC is initiated. oIf the PRB usage of the target cell satisfies „CurrentGbrPrbUsage + ExpectedPrbUsage < MaxGbrPrbUsage‟, the call is admitted. If not, the call is rejected. An estimated PRB usage for the GBR bearer is accumulated to currentGbrPrbUsage usage if the GBR bearer is requested and admitted before currentGbrPrbUsage usage is updated. oIf admission constrol based on packet delays of existing GBR bearers is activated and the estimated packet delays of existing GBR bearers are greater than threshold, the call is reject. If not, the call is admitted.


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5) If the call is admitted, the RRC Connection Reconfiguration message is transmitted to the UE to perform the Intra-eNB Handover procedure. If the call is rejected, the CAC function controls the flow of each call by interworking with the preemption function per E-RAB (DRB) determining whether to admit E-RAB. (Partial success per E-RAB is not considered.) 6) The RRC Connection Reconfiguration Complete message is received from the UE. Inter-eNB Handover Figure below depicts the Inter-eNB Handover subject to Capacity and QoS based CAC.

1) The eNB receives a measurement report from a UE. 2) The source eNB determines HO and sends the target eNBs a Handover Request message. 3) The eNB performs capacity-based CAC (LTE-SW4101). 4) If the capacitiy-based CAC is passed, when the E-RAB has the GBR, the QoSbased CAC is initiated. oIf the backhaul BW satisfies CurrentGbrBwUsage + ExpectedBw < MaxGbrBw, the call is admitted.


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oIf not, the call is rejected. If the PRB usage of the target cell satisfies CurrentGbrPrbUsage + ExpectedPrbUsage < MaxGbrPrbUsage, the call is admitted. If not, the call is rejected. An estimated PRB usage for the GBR bearer is accumulated to currentGbrPrbUsage usage if the GBR bearer is requested and admitted before currentGbrPrbUsage usage is updated. oIf admission constrol based on packet delays of existing GBR bearers is activated and the estimated packet delays of existing GBR bearers are greater than threshold, the call is reject. If not, the call is admitted. 5) If the call is admitted, the Handover Request Acknowledge message is transmitted to the source eNB to initiate the inter-eNB handover. 6) The source eNB transmits the RRC connection reconfiguration message to the UE and performs SN Status Transfer. 8~10) After path switch procedure, the target eNB sends Release Request the source eNB


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-CELL-CAC and set QOS_CAC_OPTION to QoSCAC_option1. (use) Deactivation Procedure Run CHG-CELL-CAC and set QOS_CAC_OPTION to QoSCAC_option0. (no_use)

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CELL-CAC/RTRV-CELL-CAC Parameter

Description

QOS_CAC_OPTION

The policy of the QoS (Quality of Service) based CAC (call admission control) at the cell level. QoSCAC_option0: The QoS based CAC function at the cell level is not used.


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Description QoSCAC_option1: The QoS-based CAC function per cell is used.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ENB-CAC/RTRV-ENB-CAC/CHG-CELLCAC/RTRV-CELL-CAC Parameter

Description



MAX_ENB_CALL_COUNT

The limit for capacity based CAC (call admission control) at the eNB level. The number of calls that can be allowed by the eNB.

CALL_CAC_THRESH_FOR_ NORMAL

The percentage of the allowable calls to the total normal calls. When a normal call is requested, if the number of connected calls exceeds MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_NORMAL, the Capacity-based CAC Fail is generated.

CALL_CAC_THRESH_FOR_E MER_HO

Emergency call availability of total handover calls in percentage. When a normal call is requested, if the number of connected calls exceeds MAX_ENB_CALL_COUNT * CALL_CAC_THRESH_FOR_EMER_HO, the Capacity-based CAC Fail is generated.

CHECK_UE_ID _USAGE

Whether to execute the SAE Temporary Mobile Station Identifier (S-TMSI) Duplication Check function for a new call. ci_no_use: The S-TMSI Duplication Check function is not performed. ci_use: The S-TMSI Duplication Check function is performed. If a call is found as a duplicate, the existing call is released and the new call is accommodated.

CELL_NUM

The cell number. This value must not exceed the maximum number of cells supported by the system. It is determined by Carrier/Sector. For example, if the maximum capacity system is 1 Carrier/3 Sector, up to 3 cells are supported.

CELL_COUNT_CAC_USAGE

Whether to execute the call count-based CAC function, which is one of the capacitybased Call Admission Control (CAC) functions per cell. ci_no_use: The capacity-based CAC function per cell is not performed. ci_use: The capacity-based CAC function per cell is performed.

MAX_CALL_COUNT

The call count limit in the capacity based CAC (call admission control) at the cell level. The number of calls that can be allowed by the cell.

DRB_COUNT_CAC_USAGE

Whether to execute the E-UTRAN Radio Access Bearer (E-RAB)-based CAC function, which is one of the capacity-based Call Admission Control (CAC) functions per cell. ci_no_use: The E-RAB count-based CAC function per cell is not executed. ci_use: The E-RAB count-based CAC function per cell is executed.

MAX_DRB_COUNT

The limit for the E-RAB (E-UTRAN Radio Access Bearer) count in capacity based CAC (call admission control) at the cell level. The number of E-RABs (E-Utran Radio Access Bearers) allowed in the cell.

DRB_CAC_THRESH_FOR_N

The percentage of the allowable calls to the total normal calls. When a normal


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Chapter 2 Call Control Parameter ORMAL

Description call is requested, if the number of connected calls exceeds ‘MAX_DRB_COUNT *DRB_CAC_THRESH_FOR_NORMAL’, the Capacitybased CAC Fail is generated.

DRB_CAC_THRESH_FOR_E MER_HO

Emergency call availability of total handover calls in percentage. When a normal call is requested, if the number of connected calls exceeds ‘MAX_DRB_COUNT *DRB_CAC_THRESH_FOR_EMER_HO’, the Capacitybased CAC Fail is generated.

QOS_CAC_OPTION

The policy of the QoS (Quality of Service) based CAC (call admission control) at the cell level. QoSCAC_option0: The QoS based CAC function at the cell level is not used. QoSCAC_option1: The QoS-based CAC function per cell is used.

QOS_POLICY_OPTION

The policy used when executing the Quality of Service (QoS)-based Call Admission Control (CAC) function per cell. QoSPolicy_option0: For a GBR bearer newly requested, the PRB usage is calculated based on the resource type (GBR or non-GBR) of the QCI. Then CAC is executed based on the calculated PRB usage. Non-GBRs are always allowed. QoSPolicy_option1: For a GBR bearer newly requested, the PRB usage is calculated based on the priority of the QCI. Then CAC is executed based on the calculated PRB usage. Non-GBRs are always allowed.

PRB_REPORT_PERIOD

PRB (Physical Resource Block) report period for QoS CAC at the cell level.

ESTIMATION_OPT

The policy of the Expected PRB usage calculation. (0: auto, 1: manual) EstimationOption_auto(0): The PRB Usage is automatically calculated. EstimationOption_manual(1): The PRB Usage is manually calculated.

PREEMPTION_FLAG

Whether to use preemption at the cell level. ci_no_use: The Preemption function per cell is disabled. ci_use: The Preemption function per cell is enabled.

BH_BW_CAC_USAGE

Whether to use backhaul bandwidth based CAC at the cell level. ci_no_use: Backhaul Bandwidth-based CAC function per cell is not used. ci_use: Backhaul Bandwidth-based CAC function per cell is used.

BH_BW_CAC_OPTION

The policy used when executing the Backhaul-based Call Admission Control (CAC) function per cell. bhBwCac_Qci_only: QoS-based CAC. bhBwCac_ServiceGroup_only: Service group-based CAC. bhBwCac_Both_Qci_ServiceGroup: QoS amp; Service group-based CAC.

dlGBRUsageThreshNormal

This parameter is the percentage (%) of GBR that can be allocated as downlink for normal calls. If the downlink GBR PRB usage amount exceeds the entered parameter ratio when a new call is requested, the QoS CAC Fail is generated.

dlGBRUsageThreshHO

This parameter is the percentage (%) of GBR that can be allocated as downlink for handover calls. If the downlink GBR PRB usage amount exceeds the entered parameter ratio when a handover call is requested, the QoS CAC Fail is generated.

ulGBRUsageThreshNormal

This parameter is the percentage (%) of GBR that can be allocated as uplink for normal calls. If the uplink GBR PRB usage amount exceeds the entered parameter ratio when a new call is requested, the QoS CAC Fail is generated.

ulGBRUsageThreshHO

This parameter is the percentage (%) of GBR that can be allocated as uplink for handover calls. If the uplink GBR PRB usage amount exceeds the entered parameter ratio when a handover call is requested, the QoS CAC Fail is generated.


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Description

BundlingUsageThreshNormal

The threshold of using TTI bundling that can be assigned per cell. It is used when a new call is requested. It is calculated as 'PRB percentage'. When a new call is requested, if the GBR PRB usage exceeds this parameter value, the QoS CAC Fail is generated.

BundlingUsageThreshHO

The threshold of using TTI bundling that can be assigned per cell. It is used when a Handover call is requested. It is calculated as 'PRB percentage'. When a Handover call is requested, if the GBR PRB usage exceeds this parameter value, the QoS CAC Fail is generated.

delayQosCacUsage

Whether to use or not delay based CAC. It is running when the number of GBR is the same or larger than delayQosCacBearerCountThresh.

delayQosCacBearerCountThre sh

Delay based CAC is running when the number of GBR is the same or larger than delayQosCacBearerCountThresh.

qci1_2SumCacUsage

To support sum of QCI1 + QCI2 bearer based CAC. max 5 points can be configured.

point0Usage

usage of point0 at sum of QCI1 + QCI2 bearer based CAC

qci1Point0

number of max qci1 at point0

qci2Point0


point1Usage


qci1Point1


qci2Point1


point2Usage


qci1Point2


qci2Point2


point3Usage


qci1Point3


qci2Point3


point4Usage


qci1Point4


qci2Point4


ulLcg1Thresh

delay based CAC threshold for UL LCG1.

ulLcg2Thresh

delay based CAC threshold for UL LCG2.

Parameter Descriptions of CHG-QCI-VAL/RTRV-QCI-VAL Parameter

Description

dlPdcpSduDelayThresh

For delay based CAC, DL pdcp sdu delay threshold is configured using this parameter. It is noted that it is aplied to QCI = 1 only.



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REFERENCE [1] 3GPP TS36.300, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS23.203, Technical Specification Group Services and System Aspects; Policy and charging control architecture


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LTE-SW4103, Preemption INTRODUCTION In case of no resource available, eNB can admit a new bearer by preempting existing bearers. This feature can be used to give admission to priority users even in congestion. The decision is based on Allocation and Retention Priority (ARP) information of new bearer(s) and existing bearer(s). ARP consists of priority level, preemption capability, and preemption vulnerability, which are delivered from MME to eNB during E-RAB establishment. When there are multiple preemptive candidate bearers, the eNB selects a longest call. MME has responsibility to configure appropriate ARP per each bearer.

BENEFIT Operator can provide a differentiated service that allows a high-priority UE to access the network even in congestion.

DEPENDENCY AND LIMITATION Dependency MME to support this feature Limitation A connected UE could experience a call drop when eNB is congested.

FEATURE DESCRIPTION Functional Architecture for CAC Following table shows a functional architecture for call admission control. Capacity based CAC has impact on the RRC connection establishment and E-RAB bearer establishment while QoS based CAC and Pre-emption has impact on ERAB bearer establishment only. This section covers preemption. For other two CAC features, refer to LTE-SW4101 "LTE-SW4101, Capacity based Call Admission Control" on page 오류! 책갈피가 정의되어 있지 않습니다. and LTE-SW4102.


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Preemption function is applied to GBR and non-GBR bearers in case of no resources available. Related resources are the number of bearers defined per cell. If operator provides QoS service and has limited resources that can be allocated to GBR bearers, the lack of GBR bearers, PRBs and backhaul bandwidth can trigger preemption function. In this case, an existing GBR bearer will be preempted. eNB follows the preemption rules defined in 3GPP TS36.413. If there are multiple preemption candidates that have the same ARP, eNB will select a candidate bearer at random. Parameter

Presence

Range

IE Type and reference

Semantics Description

Priority Level

M

-

INTEGER (0.. 15)

The priority of allocation and retention. Value 15 means 'no priority'. Values between 1 and 14 are ordered in decreasing order of prioirty, i.e 1 is the highest and 14 the lowest. Value 0 shall be treated as a logical error if received.

Pre-emption Capability

M

-

ENUMERATED (shall not trigger pre-emption,may trigger pre-emption)

This indicates the pre-emption capability of the request on other E-RABs. The E-RAB shall not pre-empt other ERABs or, the E-RAB may pre-empt other E-RABs. The Pre-emption Capability indicator applies to the allocation of resources for an E-RAB and as such it provides the trigger to the pre-emption procedures/processes of the eNB.

Pre-emption Vulnerability

M

-

ENUMERATED(not preemptable, pre-emptable)

This IE indicates the vulnerability of the E-RAB to preemption of other E-RABs. The E-RAB shall not be pre-empted by other E-RABs or the E-RAB may be pre-


234


Presence

Range

IE Type and reference

Semantics Description empted by other RABs. Pre-emption Vulnerability indicator applies for the entire duration of the E-RAB, unless modified and as such indicates whether the E-RAB is a target of the pre-emption procedures/processes of the eNB.

Handover of Preempted UE The preempted UE can be handed over to a neighbor cell. The eNB sends MR Solicitation to the preempted UE and it performs handover procedures based on the measurement result from the UE. If multiple carriers are available, they are all configured for the measurement. Operator can configure handover thresholds appropriately for the peemption case. Operator can enable or disable the handover of preempted UE. According to eNB and UE situation, call procedure executed can be divided as follows:

Inter-frequency handover: The UE to be pre-empted supports multiple E-UTRA carriers, and inter-frequency handover is available according to the CAC preemption handover function.

Intra-frequency handover: The UE to be pre-empted does not support multiple EUTRA carriers, and intra-frequency handover is available according to the CAC pre-emption handover function.

Inter-frequency redirection: The UE to be pre-empted supports multiple E-UTRA carriers, and inter-frequency handover is not available according to the CAC pre-emption handover function.

RRC connection release: The UE to be pre-empted does not support multiple EUTRA carriers; or it supports multiple E-UTRA carriers, but inter-frequency handover and inter-frequency redirection are not available according to the CAC pre-emption handover function. The following is the operation flow before the CAC pre-emption handover function executes.


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1 Upon receiving a new "call/bearer setup or handover" request, the eNB performs CAC function.

2 After CAC function is performed in 1), if the new "call/bearer setup or handover" request can be accepted without pre-emption, the request is accepted and the next procedure is performed.

3 After CAC function is performed in 1), if pre-emption is needed, pre-emption function is performed to decide whether pre-emption of the existing call is available.

4 If pre-emption of the existing call is available in 3), the new "call/bearer setup or handover" request is accepted, and the next procedure is performed.

5 CAC pre-emption handover function is performed for the pre-empted call selected in 3). CAC pre-emption handover is operated only when the entire call is pre-empted. When only some bearers of a call are pre-empted, CAC pre-emption handover is not operated for the call.

6 If pre-emption of the existing call is unavailable in 3), the new "call/bearer setup or handover" request is rejected, and the next procedure is performed. The CAC pre-emption handover function can be described as follows:


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0) The eNB operates CAC pre-emption handover function according to the result of the CAC/pre-emption performance. (Continued from the [A] of the operation flow before the CAC pre-emption handover function executes.)

1 The eNB judges whether there is enough resource available for the CAC preemption handover process. oIf the CAC pre-emption handover process is available in 1), step 2) is performed. oIf the CAC pre-emption handover process is not available in 1), step 7) is performed.

2 The eNB decides the target carrier which will handover the pre-empted call. oIf the UE does support multiple E-UTRA carriers, one of the carriers that is not a serving carrier is selected. oIf the UE does not support multiple E-UTRA carriers, the serving carrier is selected.

3 The eNB solicits the UE for measurement report for the target carrier selected in 2). At this moment, it starts a wait timer in order to determine whether the measurement solicitation fails.

4 When the measurement report message is received from the UE while the wait timer of 3) is in operation, the eNB checks if there exist neighbor cells whose UE measurement results are above the configured threshold.


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5 If there exist neighbor cells whose UE measurement results are above the configured threshold in 4), the best cell is selected among cells and handover preparation procedure starts.

6 If the handover preparation succeeds in 5), the UE to be pre-empted is directed to perform handover.

7 If one of the events below occurs during 4)-6), CAC pre-emption handover is unavailable. Thus it should be judged whether inter-frequency redirection is available. oThe wait timer of 3) expires while the measurement report message is not received from the UE yet. oIn the step 4), there is no neighbor cell whose UE measurement result is above the configured threshold. oIn the step 5), the handover preparation fails.

8 In the step 7), if the UE does support multiple E-UTRA carriers, one of the carriers that is not a serving carrier is selected and inter-frequency redirection is performed.

9 In the step 7), if the UE does not support multiple E-UTRA carriers, interfrequency redirection is unavailable. Thus, RRC connection release procedure is performed.

SYSTEM OPERATION How to Activate Operator can enable the preemption function by setting PREEMPTION_FLAG to USE with CHG-CELL-CAC.

When this function is disabled, eNB ignores the ARP information received from MME and it does not admit a new bearer when the configured maximum number of bearers is all used.

Operator can also enable the preemption handover function by setting ACTIVE_STATE to ACTIVE with CHG-PREEMPT-HO.

Key Parameters RTRV-CELL-CAC/CHG-CELL-CAC Parameter

Description

CELL_NUM


PREEMPTION_FLAG

This parameter decides whether the cell enables or disables the use preemption functionality.

RTRV-PREEMPT-HO/CHG- PREEMPT-HO


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Description

CELL_NUM


ACTIVE_STATE

Whether to use the Preemption Handover Function

PREEMPTION_HO_THRESH RSRP threshold used for triggering the EUTRA measurement report for OLD_RSRP Preemption Handover. PREEMPTION_HO_THRESH RSRQ threshold used for triggering the EUTRA measurement report for OLD_RSRQ Preemption Handover.


Type Name

Type Description

Preemption Handover per ERAB

PreemptHoDropBearerIntra

Number of bearers released as a result of inter-eNB HO failure while performing intraeNB HO due to CAC preemption HO operation

PreemptHoBearerIntra

Number of bearers handed over as a result of successful intra-eNB HO among the bearers on which preemption HO is performed instead of being released due to CAC preemption HO operation

PreemptHoDropBearerInterX2

Number of bearers released as a result of X2HO failure while performingX2HO due to CAC preemption HO operation

PreemptHoBearerInterX2

Number of bearers handed over as a result of successful inter-eNB X2HO among the bearers on which preemption HO is performed instead of being released due to CAC preemption HO operation

PreemptHoDropBearerInterS1

Number of bearers released as a result of S1HO failure while performingS1HO due to CAC preemption HO operation

PreemptHoBearerInterS1

Number of bearers handed over as a result of successful inter-eNB S1HO among the bearers on which preemption HO is performed instead of being released due to CAC preemption HO operation

PreemptHoErabCnt

Count of Preemption Handover per ERAB collected

PreemptHoErabTargetEarfcnDL TargetEarfcnDl requested for collection Preemption Handover

PreemtIntraEnbAtt

Intra-handover attempt count.

PreemtIntraEnbPrepSucc

Total intra handover preparation success count

PreemtIntraEnbSucc

Total intra handover execution success count

PreemtInterX2OutAtt

X2-based preemption handover attempt count in SeNB

PreemtInterX2OutPrepSucc

X2-based preemption handover preparation success count in SeNB

PreemtInterX2OutSucc

X2-based preemption handover execution success count in SeNB

PreemtInterS1OutAtt

S1-based preemption handover attempt count in SeNB


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Type Name

Type Description

PreemtInterS1OutPrepSucc

S1-based preemption handover preparation success count in SeNB

PreemtInterS1OutSucc

S1-based preemption handover execution success count in SeNB

NoAvailableTargetCarrier

Counted when redirection is performed to the serving carrier because the target carrier of the UE does not exist during preemption HO.

MrSolicitFail

Counted when redirection is performed because MR solicit is performed by specifying a target carrier for preemption HO but no target cell above the MR threshold for preemption HO is identified within the specified timer period or report amount.

HoPrepFail

Counted when redirection is performed due to intra/S1/X2 HO preparation failure although a target carrier for preemption HO is specified and a target cell is specified as a result of successful MR solicit.

PreemptHoCnt

Count of Preemption Handover collected

PreemptHoTargetEarfcnDL

TargetEarfcnDl requested for collection

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol (S1AP), Section 9.2.1.60


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LTE-SW4106, Call Admission Control per QCI INTRODUCTION In order to utilize limited resources of the eNB efficiently and prevent the eNB from being overloaded, management of the resources is needed. Call Admission Control (CAC) can be used for these purposes. Bearer admission control per QCI can be performed through CAC per QCI.

BENEFIT Operator can control bearer admission per QCI


FEATURE DESCRIPTION In QCI based CAC, call types for CAC is more classified, that is, CAC is applied per each QCI while Capacity based CAC is performed based on the number of total bearer and QoS based CAC is only applied to GBR bearer. When RRC connection is set up, capacity based CAC is applied since QCI is not known in this stage. QCI based CAC can be applied when a bearer is created/activated or call is handed in. At this moment, the applicable admission control procedure can be described as follows:

1 Capacity based CAC: checks whether the bearer can be admitted or not based on the pre-configured number of bearer. Detailed procedure can be found in LTESW4101 description.

2 QoS based CAC: checks whether the GBR bearer can be admitted or not based on the PRB usage and BH usage, if the bearer is GBR and this feature is enabled. Detailed procedure can be found in LTE-SW4102 description.

3 QCI based CAC: checks whether the bearer can be admitted or not based on preconfigured number of bearers to the corresponding QCI. a) If the current number of bearers with the same QCI as that of the bearer is less than the threshold, the bearer is admitted. b-1) If the current number of bearers with the same QCI as that of the bearer is equal to the threshold and the pre-emption is off, the bearer is not admitted. b-2) If the current number of bearer with the same QCI as that of the bearer is equal to the threshold and the pre-emption is on, pre-emption is tried according to its ARP value. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

241


SYSTEM OPERATION How to Activate The administrator set QCI DRB CAC to change QCI_DRB_CAC_USAGE, STATUS.

Define the DRB count information of QCI for CAC by cell and perform CAC for the definition.

Key Parameters CHG-CELL-CAC/RTRV-CELL-CAC Parameter

Description

CELL_NUM


QCI_DRB_CAC_USAGE

CI_no_use: Disables the DCAC Per QCI function. CI_use: Enables the CAC Per QCI function.

PREEMPTION_FLAG

CI_no_use: If a new bearer cannot be taken over while performing the CAC Per QCI function, reject the bearer. CI_use: If a new bearer cannot be taken over while performing the CAC Per QCI function, preempt the existing bearer to take over the new bearer.

CHG-QCIDRB-CAC/RTRV-QCIDRB-CAC Parameter

Description

CELL_NUM

The cell number to be changed or retrieved.

DB_INDEX

Index of the QCI to perform the CAC Per QCI function.

STATUS

N_EQUIP (= 0): The dbIndex information is invalid. EQUIP (= 1): The dbIndex information is valid.

QCI_VALUE

QCI value to perform the CAC Per QCI function.The standard QCI defined in the standard document is 1-9. 0. 10-255 can be used by an operator arbitrarily.

MAX_DRB_COUNT

MAX DRB Count of QCI to perform the CAC Per QCI function.


REFERENCE [1] 3GPP TS36.300, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS23.203, Technical Specification Group Services and System Aspects; Policy and charging control architecture


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LTE-SW4201, Standard QCI Support INTRODUCTION The Standard QCI Support feature allows an eNB to ensure that the necessary QoS for a bearer over the radio interface is met. Each bearer has an associated QoS Class identifier (QCI), and an Allocation and Retention Priority (ARP). Each QCI is characterized by priority, packet delay budget, and acceptable packet loss rate.

BENEFIT This feature enables operator to plan a variety of premium services: end-to-end QoS differentiated services in 9 different levels as per defined in 3GPP standard.

Operator can provide high-quality VoLTE service by using guaranteed bit rate bearers.

Operator can provide different user classes for different quality of services. Users can use a premium service that provides better quality even in congestion.

DEPENDENCY None

LIMITATION None


FEATURE DESCRIPTION The QoS characteristics of QCI 1~9 are standardized by 3GPP. With this feature, the eNB allows applications/services mapped to that QCI to acquire the same minimum level of QoS in multi-vendor network deployments and in case of roaming.


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Each Service Data Flow (SDF) is associated with one and only one QCI. The QCI is used as a reference to node specific parameters that control packet forwarding treatment (for example, scheduling weights, admission thresholds, queue management thresholds, link layer protocol configuration, and so on) and that have been pre-configured by the operator. Table below outlines 9 standard QCIs defined in 3GPP LTE standard. QCI

Resource Type

Priority

Packet Delay Budget

Packet Error Loss Rate

Example Services

1

GBR

2

100 ms

10-2

Conversational Voice

2

GBR

4

150 ms

10-3

Conversational Video (Live Streaming)

3

GBR

3

50 ms

10-3

Real Time Gaming

4

GBR

5

300 ms

10-6

Non-Conversational Video (Buffered Streaming)

5

Non-GBR

1

100 ms

10-6

IMS Signalling

6

Non-GBR

6

300 ms

10-6

Video (Buffered Streaming) TCPbased (e.g. www, e-mail, chat, ftp, p2p file sharing, progressive video, etc.)

7

Non-GBR

7

100 ms

10-3

Voice, Video (Live Streaming) Interactive Gaming

8

Non-GBR

8

300 ms

10-6


9

Non-GBR

9

300 ms

10-6


A standardized QCI and corresponding characteristics is independent of the UE's current access (3GPP or Non-3GPP).

QCI 1-specific Parameter Support According to GSMA IR.92 document, the dedicated bearer for Conversational Voice (that is, VoLTE service) must utilize the standardized QCI value of one (1). If the VoLTE and data bearers share the common radio and/or transmission parameters, the VoLTE service quality may be degraded because VoLTE bearers have different QoS requirements from data bearers. QCI 1-specific parameter support enables differential treatment of VoLTE calls.


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Maximum Transmission Number of PUCCH Scheduling Request (dsr-TransMax) During VoLTE call setup, the eNB includes dsr-TransMax value, which means the maximum transmission number of PUCCH Scheduling Request, separately configured for QCI 1. This parameter is contained in SchedulingRequestConfig IE of RRC Connection Reconfiguration message when dedicated bearer of QCI 1 is set up. This operation also applies to the case of handover. The target eNB includes this QCI 1-specific value when it sends Handover Command message to the source eNB. When VoLTE call is released, it is configured back again to the common dsr-TransMax value.


How to Activate This section provides the information that you need to configure the feature. Preconditions It is recommended for operators not to change standard QCI related configurations. Activation Procedure/Deactivation Procedure This feature runs automatically, and it cannot be disabled.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters There are no specific parameters associated with this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-QCI-VAL/RTRV-QCI-VAL Parameter

Description

QCI

This parameter is the QoS Class Identifier (QCI). The range is 0-255.The standard QCI defined in the standard document is 1-9. 0 and 10-255 can be used by the operator optionally. [Related Specifications] 3GPP TS 23.203 [Table 6.1.7] Standardized QoS characteristics.

STATUS

This parameter indicates the whether to use the QoS Class Identifier (QCI). EQUIP: eNB uses the relevant QCI. N_EQUIP: eNB does not use the relevant QCI.

RESOURCE_TYPE

This parameter is the resource type of the QoS Class Identifier (QCI). NonGBR: Sets the resource type of the QCI to non-Guaranteed Bit Rate (GBR).


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Description GBR: Sets the resource type of the QCI to Guaranteed Bit Rate (GBR).

PRIORITY

This parameter is the priority of the QoS Class Identifier (QCI). The range is 0.5 to 16.0, and 0.5 means the highest priority.

PDB

This parameter is the Packet Delay Budget (PDB) of the QoS Class Identifier (QCI). pdb50 msec: PDB of the QCI is 50 msec. pdb60 msec: PDB of the QCI is 60 msec. pdb75 msec: PDB of the QCI is 75 msec. pdb100 msec: PDB of the QCI is 100 msec. pdb150 msec: PDB of the QCI is 150 msec. pdb200 msec: PDB of the QCI is 200 msec. pdb250 msec: PDB of the QCI is 250 msec. pdb300 msec: PDB of the QCI is 300 msec. pdb350 msec: PDB of the QCI is 350 msec. pdb400 msec: PDB of the QCI is 400 msec. pdb450 msec: PDB of the QCI is 450 msec. pdb500 msec: PDB of the QCI is 500 msec.

SCHEDULING_TYPE

Scheduling type of the QoS Class Identifier (QCI). Entered parameter value is used for scheduling in the MAC layer. Dynamic_scheduling: The QCI uses the dynamic scheduling. SPS_scheduling: The QCI uses the SPS scheduling.

UPLINK_FORWARD

This parameter determines whether to perform Uplink Data Forwarding from the target eNB on the bearer that has the QCI during handover. 0: Disables the Uplink Data Forwarding function (Not Uplink Data Forwarding). 1: Enables the Uplink Data Forwarding function (Uplink Data Forwarding).

DOWNLINK_FORWARD

This parameter determines whether to perform Downlink Data Forwarding from the target eNB on the bearer that has the QCI during handover. 0: Disables the Downlink Data Forwarding function (Not Downlink Data Forwarding). 1: Enables the Downlink Data Forwarding function (Downlink Data Forwarding).

Parameter Descriptions of CHG-DPHY-SR/RTRV-DPHY-SR Parameter

Description

DSR_TRANS_MAX_FOR_QC I1

The maximum number of transmitting scheduling request before UE gets PUSCH resource allocation for QCI 1 bearer.


REFERENCE [1] 3GPP TS 23.203, Technical Specification Group Services and System Aspects; Policy and charging control architecture eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LTE-SW4202, Operator Specific QCIs Support INTRODUCTION In addition to standard QCIs, the Operator Specific QCIs Support feature allows an eNB to support extended QCIs that ranges from 128 to 254.

BENEFIT Operator can define a customized QCI for a specific service, where QoS characteristics of the extended QCIs may be different from those of standard QCIs in terms of priority, resource type, packet delay budget.

UE can receive a customized network service that is suitable to a specific application.

DEPENDENCY For the use of operator-specific QCIs, EPC and UE must recognize the operatorspecific QCIs and they shall behave to support the QoS level.

LIMITATION According to 3GPP standard, operator-specific QCIs shall range between 128 and 254.

LSM may have limitation on the number of operator specific QCIs because additional QCIs increase the amount of PM data.


FEATURE DESCRIPTION Samsung eNB enables operator to define extended QCIs. Operator can determine the resource type, priority and packet delay budget of the extended QCIs through LSM. The rule check function in LSM prevents operator from putting a wrong value that is out of allowed range and it also prevents from putting an overlapped QCI indexes. These QoS characteristics have the same meaning that 3GPP defines for standard QCIs. The eNB handles the extended QCIs based on those QoS characteristics configured by operator. For the use of extended QCIs, UE and EPC shall recognize the extended QCIs and support the QoS characteristics too. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Table below outlines the parameters for operator-specific QCI. Parameter for Operator Specific QCI

Range

Description

QCI Index

128~254

The numbers 10~127 are reserved and cannot be used for operator-specific QCIs. Refer to 3GPP TS24.301 Table 9.9.4.3.1.

Resource Type

GBR or NonGBR

Operator can set GBR or Non-GBR for the operator-specific QCI.

Priority

0.5~16.0

Operator can select one among 16 different priority levels. The values of 0.5~1.9 have highest priority, and the values of 2.0~2.9 have second highest priority, and so on. The value of 16.0 have the lowest priority.

Packet Delay Budget

0~11

Operate can choose one among 12 different PDB indexes. Index 0 means 50 ms of PDB, index 1 means 65 ms of PDB, index 2 means 75 ms of PDB, and so on. Finally, index 11 means 500 ms.

The QoS characteristics such as resource type, priority, and packet delay budget have the same semantics as the QoS factors of the standardized QCIs. Therefore, they have the same impact on scheduling priority when the eNB sends UEs packets from bearers with the operator-specific QCIs. Operator has to configure the QCI to DSCP mapping table to reflect a newly defined operator-specific QCI, which is for DSCP marking on packets that flow through the bearers with the operator-specific QCI. In addition, operator has to configure which network queue can be used to buffer the packets with the operator-specific QCI. Depending on the queues, different network scheduling algorithm is applied, such as Deficit Round Robin or Strict Priority. The eNB supports both the standardized QCIs and operator-specific QCIs defined and enabled by operator. The eNB will reject ERAB setup request if it includes an unknown QCI.



It is recommended for operators to set for operator specific QCIs, STATUS, RESOURCE_TYPE, PRIORITY must be configured before the QCI value is activated.


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Activation Procedure Operator can retrieve or modify QCI information by running RTRV-QCI-VAL or CHG-QCI-VAL. Operator can input any QCI value from 10 to 255 but is recommended to choose one value between 128 and 254 as per the 3GPP standard. QCI, QCI, STATUS, RESOURCE_TYPE, and PRIORITY must be configured before the QCI value is activated by running CHG-QCI-VAL. Deactivation Procedure Run CHG-QCI-VAL to change the status of the operator specific QCIs to N_EQUIP.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters Parameter Descriptions of CHG-QCI-VAL/RTRV-QCI-VAL Parameter

Description

QCI


STATUS


Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-QCI-VAL/RTRV-QCI-VAL Parameter

Description

QCI


STATUS


RESOURCE_TYPE

This parameter is the resource type of the QoS Class Identifier (QCI). NonGBR: Sets the resource type of the QCI to non-Guaranteed Bit Rate (GBR). GBR: Sets the resource type of the QCI to Guaranteed Bit Rate (GBR).

PRIORITY

This parameter is the priority of the QoS Class Identifier (QCI). The range is 0.5 to 16.0, and the smaller value means the higher priority.

PDB

This parameter is the Packet Delay Budget (PDB) of the QoS Class Identifier (QCI).


249


Description pdb50 msec: PDB of the QCI is 50 msec. pdb65 msec: PDB of the QCI is 65 msec. pdb75 msec: PDB of the QCI is 65 msec. pdb100 msec: PDB of the QCI is 100 msec. pdb150 msec: PDB of the QCI is 150 msec. pdb200 msec: PDB of the QCI is 200 msec. pdb250 msec: PDB of the QCI is 250 msec. pdb300 msec: PDB of the QCI is 300 msec. pdb350 msec: PDB of the QCI is 350 msec. pdb400 msec: PDB of the QCI is 400 msec. pdb450 msec: PDB of the QCI is 450 msec. pdb500 msec: PDB of the QCI is 500 msec.

BH_SERVICE_GROUP

This parameter is the Service Group of the QoS Class Identifier (QCI). The entered parameter value is used for the backhaul Call Admission Control (CAC). voipService: The QCI uses the Voice over Internet Protocol (VoIP) service. videoService: The QCI uses the video service.

SCHEDULING_TYPE

Scheduling type of the QoS Class Identifier (QCI). Entered parameter value is used for scheduling in the MAC layer. Dynamic_scheduling: The QCI uses the dynamic scheduling. SPS_scheduling: The QCI uses the SPS scheduling.

UPLINK_FORWARD

This parameter determines whether to perform Uplink Data Forwarding from the target eNB on the bearer that has the QCI during handover. 0: Disables the Uplink Data Forwarding function (Not Uplink Data Forwarding). 1: Enables the Uplink Data Forwarding function (Uplink Data Forwarding).

DOWNLINK_FORWARD

This parameter determines whether to perform Downlink Data Forwarding from the target eNB on the bearer that has the QCI during handover. 0: Disables the Downlink Data Forwarding function (Not Downlink Data Forwarding). 1: Enables the Downlink Data Forwarding function (Downlink Data Forwarding).

CONFIGURED_BIT_RATE

This is minimum configured bit rate of standard non-GBR QCI bearer in Cell Load Calculation. If loadEvaluateMode is loadPrb, this parameter is used in Cell Load Calculation. This parameter is applied to the bearer of QCI value 5~9. loadEvaluateMode is attribute of RTRV(CHG)-ACTIVE-LB.

WEIGHT_FOR_CELL_LOAD

This is the weight value of PRB usage per non-GBR QCI in Cell Load Calculation. It is used in case that loadEvaluateMode which can be checked by CLI RTRV-ACTIVE-LB is loadPrb and the cell load is calculated automatically.

Counters and KPI There are no specific counters or Key Performance Indicators (KPIs) associated with this feature.

REFERENCE [1] 3GPP TS 23.203 Policy and charging control architecture (Release 12) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LTE-SW4203, QCI to DSCP Mapping INTRODUCTION LTE system supports the designated level of QoS for each QCI. However, the QoS support defined by LTE cannot be received if the packet passes a backhaul section between eNB and EPC. The backhaul IP network sections that cannot recognize LTE traffic require the QoS support of IP network such as DiffServ. Therefore, LTE QoS needs to be mapped to the IP network QoS in order to support LTE system‟s end-to-end QoS. For this, eNB marks an appropriate DSCP for uplink packets so that bearer QoS can be differentiated in the backhaul IP network section as well. Operator can set different DSCPs for each QCI in regard to all packets transmitted by eNB. It is also available to seta separate DSCP for the signaling message sent to MME or the OAM traffic delivered to LSM. As for DL packets, SGW should support a function of DSCP marking per QCI. In order for the backhaul IP network to support QoS, switches or routers that consist the operator IP network between eNB and SGW should be set up to support QoS based on DSCP. For example, the buffer size of each DSCP, scheduling priority, and and so on. should be set up appropriately.

BENEFIT Operator can manage traffic from eNB to SGW for end-to-end QoS service. In addition to bearer traffic, operator can setup appropriate DSCP values to signaling traffic and OAM traffic for system optimization. For example, setting a high priority on signaling message will reduce call setup time while a DSCP value for regularly generated OAM ftp traffic needs to set not to affect user traffic.

DEPENDENCY AND LIMITATION Limitation eNB can set DSCP values only for uplink packets. DSCP values for downlink packets are marked by SGW.

The DSCP value set by eNB is valid until being transmitted to SGW. In case of section between SGW and PGW, the marking rule set by the core network is followed.


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FEATURE DESCRIPTION Operator can set different DSCP values for each traffic such as QCI 1-9, Signaling (S1-MME, X2), Management, OAM, Network Control and Default as shown in the table below. This table is an example of QCI to DSCP mapping. Appropriate DSCP values can be set according to the Operator‟s backhaul network operation policy and service. QCI

DSCP Value

Traffic Type

Remarks

-

24 (CS3)

Signaling

S1/X2 signaling (including SCTP heart-beat), GTP echo, GTP error indication

-

24 (CS3)

Management

SNMP messages (Alarm, Status, Command Request/Response)

-

26 (AF31)

OAM Traffic

FTP, Logs (CSL, Trace), ICMP (between LSM and eNBs)

-

48 (CS6)

Network control

IP control (DHCP), NTP (LSM and eNBs)

1

46 (EF)

QCI-1 User Data

Conversational Voice (RTP) (CDMA Voice)

2

34 (AF41)

QCI-2 User Data

Conversational Video (Live Streaming)

3

36 (AF42)

QCI-3 User Data

Real Time Gaming

4

38 (AF43)

QCI-4 User Data

Non-Conversational Video (Buffered Streaming)

5

24 (CS3)

QCI-5 User Data

IMS Signalling

6

16 (CS2)

QCI-6 User Data

Video (Buffered Streaming), TCP-based (For example, www, e-mail, chat, ftp, and p2p)

7

18 (AF21)

QCI-7 User Data

Voice, Interactive Gaming, Video (Live Streaming)

8

20 (AF22)

QCI-8 User Data


9

22 (AF23)

QCI-9 User Data


-

0 (CS0)

Remaining Traffic

Best Effort

The backhaul network transmits and receives mixtures of various traffics such as signaling traffic, OAM traffic, bearer traffic, and network control traffic, so the traffics should be controlled according to the priority of each traffic. For instance, in case of losing signaling traffic or network control traffic, the entire service can be affected, so it requires a higher priority than a general user's traffic. In addition, latency of voice traffic is important, so it should have a higher priority than internet data traffic. Likewise, the transport QoS function is required to control the priority of each traffic type. In the Ethernet backhaul network, the IP layer and the Ethernet layer uses DSCP and CoS respectively to provide the transport QoS function. The operator can control the priorities by setting DSCP/CoS for each traffic type. Full conceptual diagram of transport QoS's is as follows.


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The same DSCP value can be mapped even if QCIs are different. In the eNB, packets are classified as different network buffers (queues) depending on the DSCP values. If the queues are different, each can have different scheduling priorities. Strict Priority Queuing (SPQ) and Deficit Round Robin (DRR) are applied for scheduling the packet transmission from these queues to the backhaul network.

SYSTEM OPERATION How to Activate CHG-DSCP-TRF changes the DSCP mapping informationper QoS Class Identifier (QCI). The changeable information is the mapped DSCP value per QCI. When operator configure the QCI value and enter a DSCP value to change, the DSCP value of QCI is changed.

CHG-DSCP-SIG changes the DSCP setting value for signal communication in an eNB. If the VirtualRouting interface is not used, the VRID value is always set to 0. If the VirtualRouting interface is used, it can configure a dscp value by using VirtualRouting id and signaling class id as an index.

CHG-SCHRDSCP-DATA changes the Smart Scheduler traffic and the mapping information of Differentiated Services Code Point (DSCP) created by Smart Scheduler and eNB. Select a traffic type using the CLASS_ID parameter and enter a DSCP value that will be applied to the traffic into the DSCP parameter.

Key Parameters CHG-DSCP-TRF/RTRV-DSCP-TRF Parameter

Description

QCI

It is a QoS class identifier (QCI) value to which the DSCP mapping information will


253


Description be set. Identifier)

DSCP

It is a DSCP value to be set for each traffic type (for each QCI).

CHG-DSCP-SIG/RTRV-DSCP-SIG Parameter

Description

VR_ID

This parameter is the virtual interface ID for signal of an eNB. If virtual interface is not supported, it is always set to 0.

CLASS_ID

It represents a signal class ID in the eNB. Each class ID is defined as follows. 0: S1 Signaling 1: X2 Signaling 2: S1/X2-U management 3: M2 signaling (It is valid in MBMS Supported System)

DSCP

It is a DSCP value to be set for each signaling traffic type generated by the system.

CHG-SCHRDSCP-DATA/RTRV-SCHRDSCP-DATA Parameter

Description

CLASS_ID

Index defined to configure Smart Scheduler traffic, and the mapping information of Differentiated Services Code Point (DSCP). 2 traffic types are defined and the traffic types corresponding to each index are as follows: 0: Smart Scheduler Traffic for D-RAN. 1: SmartSON traffic.

DSCP

DSCP value that is to be configured per Smart Scheduler traffic type.


REFERENCE [1] 3GPP TS 23.203, Technical Specification Group Services and System Aspects; Policy and charging control architecture


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LTE-SW4211, Application Aware QoS INTRODUCTION The Application Aware QoS feature supports application-aware traffic control, which controls packet rate of a specific application when the cell congestion occurs.

BENEFIT Operator can provide differentiated service according to applications within one specific non-GBR bearer to its subscribers. Some applircations such as video and web can have priority in terms of throughput and/or latency by dropping (a part of) packets of other applications such as P2P and FTP under the congestion situation.

Users can experience better quality for delay-sensitive applications even in congestion situation.

DEPENDENCY The Core Network should support DSCP marking of the UE`s IP packet and deliver to the eNB to enable this feature.

LIMITATION N/A


FEATURE DESCRIPTION According to current 3GPP standard, QoS differentiation is performed on E-RAB basis. Therefore, in most commercial LTE network, which exploits only a few non-GBR bearers, multiple different types of application (for example, video, web, email, P2P, FTP, and so on), which are delivered through one specific non-GBR bearer (usually, the default bearer), have same QoS characteristics according to QCI of the bearer, and are handled at the eNB without distinction, even in congestion situation. With this feature, the eNB can control packet rate of a specific application, which is distinguished by DSCP, when the cell congestion occurs.


255


Figure below depicts the example of the rate control for packets of DSCP = YY and DSCP = ZZ.

The rates of 100 Kbps and 200 Kbps are configured for 'YY' application and 'ZZ' application, respectively. The incoming packets for each configured application will be dropped according to their configured rate. The rate control function is activated only when the cell congestion situation as depicted figure below.

The cell congestion is determined by air resource utilization measured from Physical Resource Block (PRB) usage. The rate control is triggered when a congestion of a cell is detected (that is, PRB usage comes up the pre-configured threshold.). The eNB stops the rate control when the congestion is cleared (that is, PRB usage goes under the pre-configured threshold.).


256


Detection for Application Awareness Application differentiation is based on DSCP marked from the Core with inner IP header of data packets.

Application-Aware Traffic Control If congestion of a cell is higher than the pre-configured threshold, rate control is activated for the service with a configured DSCP.

The rate control function performs dropping (a part of) packets according to configured rate for the DSCP value.

If congestion of a cell is lower than the pre-configured threshold, rate control is de-activated for the service with a configured DSCP.

The congestion is determined based on air resource utilization measured from physical resource block (PRB) usage.

The maximum number of applications for rate control will be limited by system parameter (Currently, Max. eight DSCPs are supported).



Core Network should support DSCP marking functionality about IP packet of UE. Activation Procedure Run CHG-GTP-INF and set Changing tcFlag to ON to activate this feature. Deactivation Procedure Run CHG-GTP-INF and set Changing tcFlag to OFF to deactivate this feature.

Key Parameters Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-TWAMP-CONF Parameter

Description

TC_FLAG

This parameter is on/off configuration of Traffic Control.


257


Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-TC-POLICY Parameter

Description

cellType

This parameter is the eNB cell type. The Macro type has to input SmartCellType_OFF, and the Smart type input the SmartCellType_ON.

cellNumId

This parameter is the cell ID applied for the traffic control policy. The Macro type has to input the cell ID, and the Smart type input the Subcell ID.

dscpId

This parameter is the dscp index applied for the traffic control policy.

innerDscp

This parameter is the dscp value. dscp value means DSCP value mapping QCI of a non-GBR in PLDDSCPMapTraffic. To input the DSCP value making in Core systerm. In case the wrong parameter is set up by user, the traffic loss can happen.

dlTcBandwidth

This parameter is the maximum Bandwidth of Rate Limiting for Traffic Control. (0: disable, 1~1000000: enable)

dlTcBurstLimit

This parameter is the maximum token size in which it can be processed packet at a burst time.

Parameter Descriptions of CHG-TC-PI Parameter

Description

cellType

This parameter is the eNB cell type. The Macro type has to input SmartCellType_OFF, and the Smart type input the SmartCellType_ON.

cellNumId

This parameter is the cell ID of the traffic control PRB information. The Macro type has to input the cell ID, and the Smart type input the Subcell ID.

prbThreshold

This parameter is threshold of downlink total PRB usage. (0: disable, 1~100: enable)


Counter

Tye Description

DL_TRAFFIC_CONTROL

CellTcDLByte

This counter collects the Byte Count of DL traffic by each DSCP and each Cell.

CellTcDLPeriod

This counter specifies the CellTcDLByte collection time.

CellTcDLPacket

This counter collects the Packet Count of DL traffic by each DSCP and each Cell.

CellTcDLThruAvg

This counter collects the Average Total Throughput of DL traffic by each DSCP and each Cell.

CellTcDLThruMin

This counter collects the Minimum Total Throughput of DL traffic by each DSCP and each Cell.

CellTcDLThruMax

This counter collects the Maximum Total Throughput of DL traffic by each DSCP and each Cell.

CellTcDLDropByte

This counter collects the Drop Byte Count of DL traffic by each DSCP and each Cell.


258


Counter

Tye Description

CellTcDLDropPacket

This counter collects the Drop Packet Count of DL traffic by each DSCP and each Cell.

CellTcDLDropRatio

This counter collects the Drop Packet ratio of DL traffic by each DSCP and each Cell.

REFERENCE N/A


259


LTE-SW5500, CA Call Control INTRODUCTION Carrier Aggregation (CA) is an LTE-Advanced key feature that enhances the peak throughput and sentiment quality of UE by allowing the UE to use two or more carrier resources simultaneously. According to 3GPP standard, one UE may aggregate up to 5 carriers and 100 MHz frequency bandwidth at the same time. For this feature, eNB performs the following functions:

Selection of secondary cells (SCells) Decision on the allowance of SCell addition Delivery of the L1 and L2 configuration information for SCells The basic call processing procedures such as UE Context Setup and Handover are upgraded to support the aforementioned functions.

BENEFIT Operator can enhance the utilization of frequency resource and obtain load balance effects, and so on, for scheduling.

The UE can improve throughput and reduce file download delay.

DEPENDENCY HW dependency Support Channel Cards: Refer to Carrier Aggregation bandwidth combination features

Related Radio Technology E-UTRAN (LTE) 3GPP LTE Rel.10 Carrier Aggregation

Prerequisite Features N/A

LIMITATION UE connecting a TDD Cell does not have a FDD SCell in this release.


260


SYSTEM IMPACT Interdependencies between Features LTE-SW5500 CA Call Control and CA bandwidth combination features, which are varied by operator and eNB configuration, should be supported for carrier aggregation Performance and Capacity Carrier aggregation increases the system capacity for end-users by utilizing the available spectrum resources effectively across the network. Coverage Carrier aggregation allows end users to access the network through mulitple component carriers. Thus, the cell coverage can be increased for those CA users compared with the single-carrier users.

FEATURE DESCRIPTION The eNB supports two following operating modes to effectively support the CA development scenario of 3GPP TS36.300 Annex J: CA Operation Mode

Mode 1

Mode 2

Desirable Deployment Scenario

#1

#1, #2

Characteristics

Every PCells and SCells are 1:1 paired. The predesignated paired SCell is always configured on initial connection and HO in (Colocated)

Release and re-connection SCell based on PCell-SCell Paired, and MR at initial connection and HO in (Co-located + MR)

Configured frequency

SCell Configuration

SCell Configuration Event A2 Configuration for SCell release

Non-configured frequency

N/A

Event A4 Configuration for SCell addition

Measurement Configuration State (per carrierfrequency)

Mode 1: When UE establishes RRC-connection to a PCell or is handed over to the PCell, eNB instructs the UE to add the SCell collocated to the PCell. UE does not measure L3 radio quality of SCell.

Mode 2: When UE establishes RRC-connection to a PCell or is handed over to the PCell, eNB instructs the UE to add the SCell collocated to the PCell. UE may release and add the SCell again according to L3 measurement report of the SCell.

Check Blocks for SCell Addition Samsung eNB considers the following conditions for adding SCell: Check

Description

C1. PCell CA ON/OFF Check

This flag is configurable per PCell. If it is 0, OFF; if it is 1, ON.


261

Chapter 2 Call Control Check

Description

C3. CA Band Capability Check

If the supported BandCombinations and BandwidthCombinationsets received from UE radio capacity are supported by the eNB, success. This check is carried out for every supported BandCombination of UE.

C4. Cell Capacity Check

This step decides the allowed SCell addition based on the number of UEs of PCell and SCell. If a UE requests SCell addition beyond the maximum number of SCell added calls which allows the setting of SCell addition per PCell, the request is rejected.

C5. SCell Availability Check

This step is to check the service availability of the SCell requested by SCell addition as follows: SCell cell release: If the state of the cell requested as SCell is cell released, impossible to add SCell. SCell shutting down state: If the state of the cell requested as SCell is shutting down, impossible to add SCell. SCell barring or reserving: Decides the possibility of adding SCell considering all cells barred and reservedforOperatorUse of SCell.

C6. Co-Schedulability Check

This steup is to check whether co-scheduling of PCell and SCell is allowed or not. By using IDs set in expansion to cell configuration, set the SchedulableUnit as a parameter and if the cell requested as SCell is in the SchedulableUnit same as PCell, success; otherwise, failure.

C8. UE FGI 112 Check

If FGI bit 112 is 1, success; if it is 0, failure.

C4 Checking is moved to SCell activation stage.

Basic Operation for CA At the Setup of Initial Context Setup (Mode 1, 2) The eNB performs checks in serial order to determine the CA availability on obtaining the UE capability (at the reception of initial context setup request or of UE capability information),

C1. PCell CA ON/OFF Check C3. CA Band Capability Check C5. SCell Availability Check If the conditions C1 and C3 are met according to the CA operation modes, eNB sends the following configurations in the RRC Connection Reconfiguration message transmitted to the UE in the conventional setup procedures. In case of Mode 1, If C5 is satisfied for the paired SCell, the eNB configures the UE to add the paired SCell that meets C3 condition. In case of Mode 2, If C5 is satisfied for the paired SCell, the eNB configures the UE to add paired SCell that meets C3 condition; and configures the event A2 measurement for SCell release.


262


If neither of conditions is failed, the eNB performs the conventional initial context setup procedure, that is, the UE does not perform any other CA-related operations. Once completing the UE context setup, even if the states of C1 to C5 changed from CA unavailable to CA available before the release of the RRC Connection or the handout to other cells, the current SCell configuration and SCell measurement configuration are not changed. As ever, even if the conditions C1 to C5 during RRC connection changed CA available state to CA unavailable state, the eNB does not perform SCell release nor measurement configuration. On receiving event A4 measurement for SCell addition trigger (Modes 2) Before the eNB receives Event A4 Measurement Report (MR) for SCell addition, the UE is supposed to have no added SCell at the SCC. The eNB performs the following in serial order for the neighbor cell triggering the event on receiving Event A4 MR for SCell addition trigger:

C6. Co-Schedulability Check C5. SCell Availability Check If all conditions C6 and C5 are satisfied, eNB sends the UE a separate RRCConnectionReconfiguration message to set the following: In case of Mode 2,

Add the reported neighbor cell triggering Event A4 as SCell; Release event A4 measurement on the SCC of the added SCell; and Configure the event A2 measurement for releasing SCell whose the SCC of the added SCell is Measurement Object (MO). On receiving event A2 MR for SCell release trigger (Modes 2) On receiving event A2 MR for SCell release trigger, the eNB sends the UE a separate RRCConnectionReconfiguration message for the UE to set the following:

SCell release in the SCC corresponding to MO of the triggered event A2; Release of event A2 measurement for SCell release at SCC of the released SCell is MO;

Configuration of event A4 measurement for SCell addition at SCC of the released SCell is MO; and On receiving RRC connection re-establishment The eNB performs the following just after receiving the RRCConnectionReestablishment message from the UE:

Release of all SCells configured. Just after the RRC connection REestablishment (RRE) procedure, the configuration related to the CA on the RRCConnectionReconfiguration message is performed as same as the RRC connection establishment.


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Operation at intra-eNB handover If the CA supporting eNB receives a HO event MR and the neighbor cell triggering the event is a cell belonging to the eNB including the PCell, the following check operations are performed in serial order to determine the CA availability in the target cell:

C1. PCell CA ON/OFF Check C3. CA Band Capability Check C6. Co-Schedulability Check C5. SCell Availability Check Based on the conditions according to the CA operating modes, the eNB adds the following configurations in the RRCConnectionReconfiguration message including MobilityControlInfo. In case of Mode 1, If all conditions C1 and C3 are satisfied, and C5 is satisfied for the paired SCell, the UE is configured to add the paired SCell on the SCC. In case of Mode 2,

If all conditions C1 and C3 are passed, and C5 is satisfied for the paired SCell, the UE is configured to add the paired SCell on the SCC.

The eNB configures event A2 measurement for SCell release at SCC of the added SCell is MO. Operation at inter-eNB handover (X2, S1 HO) Operation of Source eNB

In inter-eNB HO procedure, the source eNB sends the target eNB the S1AP: or X2AP: Handover Request message including the follows.

Serving SCell list (sCellToAddModList) set by the source eNB CandidateCellInfoList on the serving frequencies. UE-RadioAccessCapability. Operation of Target eNB

When the target eNB supporting CA receives the S1AP: or X2AP:Handover Request message from the source eNB, it performs the following check operations in serial order to determine the CA availability of the UE from the source eNB:

C1. PCell CA ON/OFF Check C3. CA Band Capability Check C6. Co-Schedulability Check C5. SCell Availability Check C8. UE FGI bit 112 Check If all conditions C1 to C3 are satisfied, eNB configures as followings: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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In case of Mode 1, If C5 is satisfied for the paired SCell, the eNB configures the UE to add paired SCell that meets C3. In case of Mode 2,

If C5 is satisfied for the paired SCell, the eNB configures the UE to add paired SCell that meets C3.

The eNB configures event A2 measurement for SCell release at SCC on which the SCells are added. When the UE unsatisfied C8 performs S1 HO, and the handover type described in the S1AP: Handover Required message is either of the following cases, the target eNB does not include the configuration of SCell addition nor measurement for searching SCell in the Handover Request Acknowledge message, but configures one more separate RRC Connection Reconfiguration message after the completion of the handover of the UE.

UTRANtoLTE GERANtoLTE Additional Feature I: PCell Frequency Switching PCell Frequency Switching enables SCell-configured UEs to perform interfrequency handover to the SCC earlier than UEs not configuring SCell, thereby SCell-configured UEs can maintain a higher throughput level compared to non-CA UEs. In addition, PCell Frequency Switching is free from PCell throughput degradation caused by measurement gap since CA UEs with a configured SCell can measure L3 channel quality of neighbor cells on the SCC without measurement gap. Setting of Related Parameters Event A2/A1 thresholds for SCell-configured UEs to trigger inter frequency searching are defined as configurable system parameters, which shall be set to higher values than those for non-CA UE. Event A3 offset/A5 threshold2 for SCell-configured UEs to trigger inter frequency handover are defined as configurable system parameters, which are recommended to set to the same or higher values than those for non-CA UEs. Operation On meeting event-triggering conditions for SCell-configured UEs, SCellconfigured UEs perform inter frequency searching and inter frequency handover to the SCC. Following figures show state transition diagram of SCell configuration and measurement configuration in PCell Frequency Switching

CA_InterF_: threshold or offset for SCell-configured UEs to trigger interfrequency carrier searching or handover

InterF_: threshold or offset for non-CA UEs (including CA UEs which do not have SCell added) to trigger inter-frequency carrier searching or handover


265


Mode 1. Operation Details

This section describes how measurements are managed in Mode 1. As described earlier, the SCell is added in Mode 1 at the time of RRC Connection Reconfiguration (if not already added). Along with the SCell addition, the CA_InterF_A2 event is configured for the PCell. This event is used to monitor the PCell level and trigger further measurements. It should be defined higher than regular A2 measurements. When the CA_InterF_A2 trigger is reported, the eNB configures CA_InterF_A1 (on PCell), CA_InterF_A3/A5, and InterF_A2 (on PCell). If the UE reports CA_InterF_A1, other measurement triggers are removed and CA_InterF_A2 is again added. If the UE reports InterF_A2, the eNB configures InterF_A1 and InterF_A3/A5 on the UE and removes other measurements. If the UE reports CA_InterF_A3/A5 (for SCell FA), the eNB performs a PCell switch in which the SCell FA becomes the new PCell and the previous PCell FA is added as the new SCell. If the UE reports InterF_A1, the eNB removes the existing measurements and adds CA_InterF_A1 (on PCell), CA_InterF_A3/A5, and InterF_A2 (on PCell). If the UE reports InterF_A3/A5, a regular handover is performed.

Mode 2. Operation Details

Mode 2 operates similarly to Mode 1 except that A2 measurements related to SCell addition and release are also added.


266


Limitation

PCell Frequency Switching does not apply to UEs having GBR bearer(s).


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature Activation Procedure Run CHG-CACELL-INFO and set CA_AVAILABLE_TYPE to DL_Only to enable carrier aggregation. Deactivation Procedure Run CHG-CACELL-INFO and set CA_AVAILABLE_TYPE to CA_OFF to disable carrier aggregation.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature.


267


Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CACELL-INFO/RTRV-CACELL-INFO Parameter

Description

CA_AVAILABLE_TYPE

This parameter indicates whether to support carrier aggregation (CA). CA_OFF DL_only DL_and_UL

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CACELL-INFO/RTRV-CACELL-INFO Parameter

Description

CELL_NUM

The cell number. This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity provided to the carrier per system is 1 FA/3 Sector, up to 3 cells are supported.

CA_AVAILABLE_TYPE

This parameter indicates whether to support carrier aggregation (CA).

P_CELL_ONLY_FLAG

This parameter indicates whether to support only P Cell.

MAX_DL_CA_CC_NUM

The maximum number of carrriers to support Downlink Carrier Aggregation.

MAX_UL_CA_CC_NUM

The maximum number of carrriers to suppeor Uplink Carrier Aggregation.

CA_OPERATION_MODE

CA Operation mode. Mode1: Pcell and Scell are colocated and the Scell is added during intiail attachment. Mode2: Pcell and Scell are colocated and intial attachment will try Scell addition. If Scell is not found, Scell will be released. Mode3: Pcell and Scell are colocated and Scell is added based on MR (measurement report). Mode4: SCell is changed by Mesasurement about SCC

Parameter Descriptions of CHG-CASCHED-INF/RTRV-CASCHED-INF Parameter

Description

SCHEDULABILITY_UNIT

This parameter is the Carrier Aggreation (CA) Schedulability unit. It indicates the range of SCells for CA in the eNB. IntraEnb: Selects SCells in the same eNB. caGroup: Selects SCells in the CA Group.

Parameter Descriptions of CHG-CA-COLOC/RTRV-CA-COLOC Parameter

Description

STATUS

This parameter indicates whether the tuple information is valid.

COLOCATED_CELL_NUM

This parameter is the number of the cells in the same eNB that are colocated with CELL_NUM. This parameter is the input range is the


268


Description maximum number of the cells that the system supports. In case of Mode1, 2, the cells specified as COLOCATED_CELL_NUM become the Scell targets.

Parameter Descriptions of CHG-TIMER-INF/RTRV-TIMER-INF Parameter

Description

S_CELL_DEACTIVATION_TIMER

This parameter is the waiting time until a Scell is deactivated by MAC. This parameter is the value set to a UE if one or more Secondary Cells (Scell) are operating during Carrier Aggregation (CA) operation. It is recommended to use a default value. Be careful when setting the value because the Scell Deactivation time becomes long if the timer v alue is large.

Parameter Descriptions of CHG-CABAND-INFO/RTRV-CABAND-INFO Parameter

Description

BAND0_USAGE

This parameter indicates whether to use Band Combination of BandEutra0 and caBandwidthClassDl0

BAND_INDICATOR0

CA-supported BandIndicator

CA_BANDWIDTH_CLASS_DL0

CA Bandwidth Class

BAND1_USAGE


BAND_INDICATOR1



CA Bandwidth Class

BAND2_USAGE


BAND_INDICATOR2



CA Bandwidth Class

BAND0_FOR_UL_USAGE

This Parameter indicates whether to use BandIndicator0 for UL CA.

CA_BANDWIDTH_CLASS_UL0

CA Bandwidth Class Of BandIndiCator0. When SupportedBandCombination-r10 in UE-EUTRA-Capability includes band parameter which consists of bandIndicator0 and caBandwidthClassUl0, This parameter can be selected PCELL Band or UL CA Band

BAND1_FOR_UL_USAGE

This parameter indicates whether to use BandIndicator1 for UL CA.


CA Bandwidth Class Of BandIndiCator1. when SupportedBandCombination-r10 in UE-EUTRA-Capability includes band parameter which consists of bandIndicator1 and caBandwidthClassUl1, This parameter can be selected PCELL Band or UL CA Band.

BAND2_FOR_UL_USAGE

This parameter indicates whether to use BandIndicator2 for UL CA.


CA Bandwidth Class Of BandIndiCator2. when SupportedBandCombination-r10 in UE-EUTRA-Capability includes band parameter which consists of bandIndicator2 and caBandwidthClassUl2, This parameter can be selected PCELL Band or UL CA Band.

Parameter Descriptions of CHG-CA-OPTION/RTRV-CA-OPTION eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

SCC_SELECTION_PRIORITY 1

This parameter is used to give priority to SCC Selection. When a high priority condition is chosen and there is more than one SCC that meets the condition, the SCC selection is determined by the condition specified in this parameter. An option that is chosen in high priority should not be chosen again, except for the option 'Not_use'. Size_of_BW: The size of BW becomes the condition for SCC selection. The SCC with bigger BW is chosen. CAC: CAC stands for Composite Available Capacity. The SCC with greater CAC is chosen. number_of_UE_with_BW: The number of UE with BW consideration becomes the condition for SCC selection. The SCC with the least amount of UE after BW normalization is chosen. operator_specific: this option exists to give the operator forced priority. OPERATOR_PREFERRED_BAND will be chose as SCC. not_use: does not give additional priority to SCC selection.

OPERATOR_PREFERRED_D L_BAND1

This parameter is to define Band Value that gives the operator forced priority for SCC selection. the selected Band value is valid if the value of sccSelectionPriority1 equals 'operator_specific'.










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Description

SCC_PLMN_SELECTION

This parameter is used to control SCell configuration capability for Cells that do not support the same PLMN as PCell's PLMN. Not_use: Set the Cell that does not support the same PLMN as PCell's PLMN as an SCell. USE: Do not set the Cell that does not support the same PLMN as PCell's PLMN as an SCell.

USE_MO_DATA_BARRING

Whether to use ac-barringforMO-data as SCell configuration condition. Not_use: Set the Cell as an SCell regardless the SIB2 MO-data-barring value. USE: Set the Cell as an SCell depenging on SIB2 MO-data-barring value. If SIB2 MO-data-barring value is 'use', Do not set the Cell as an SCell. If it is 'no_use', set as an SCell.

SCELL_CHANGE_SUPPORT

Shows whether or not Scell Change support function through SCell Release/Add is operated for UEs that do not support FGI#111, when operating in CA Mode4.

SBC_LIST_PRIORITY_USAG E

SBC List can be used with Priority up to 3. This parameter designates how many priorities can be used for CA. 1: Priority1_use: One SBC List can be used with Priority1. 2: Priority1_Priority2_use: Two SBC Lists can be used with Priority1 and Priority2. 3: Priority1_Priority2_Priority3_use: Three SBC Lists can be used with Priority1, Priority2, Priority3.

OPERATOR_PREFERRED_U L_BAND1

This parameter is to define UL Band Value that gives the operator forced priority for SCC selection. the selected Band value is valid if the value of sccSelectionPriority1 equals 'operator_specific'.

OPERATOR_PREFERRED_U L_BAND2

This parameter is to define UL Band Value that gives the operator forced priority for SCC selection. the selected Band value is valid if the value of sccSelectionPriority2 equals 'operator_specific'.

Parameter Descriptions of CHG-EUTRA-FA/RTRV-EUTRA-FA Parameter

Description

MEAS_CYCLE_SCELL

This parameter is the subframes for SCell.


Type Name

Type Description

Carrier Aggregation capable UEs(PCell)

CaCapaPCellUE

Number of CA capable UEs (PCell)

CaUECapaEnquiryAdditional Sbc

The number of sending UECapabilityEnquiry message to get additional SBC during Attach, Idle to Active, Inter-eNB Handover, Reestablishment procedures

CaUECapaInformationAdditi onalSbc

The number of receiving UECapabilityInformation after sending UECapabilityEnquiry message to get additional SBC during Attach, Idle to Active, Inter-eNB Handover, Re-establishment procedures

SCellAddAtt

Scell Addition attempt count (SCell)

Carrier Aggregation


271

Chapter 2 Call Control Family Display Name Messagecount for Addition/Releas

Type Name

Type Description

SCellAddSucc_RrcSig

Number of successes in addition to colocated SCell or successes in SCell addition by HO-in procedure (SCell)

SCellAddSucc_EventA4

Number of successes in SCell addition by Event A4 (SCell)

SCellAddSucc_EventA6

Number of successes in SCell addition (change) by Event A6 (SCell)

SCellAddSucc_RrcResetup

Number of successes in addition to SCell after RRC connection reestablishment procedures (SCell)

SCellAddFail_RrcSigTO

Number of fails in Scell addition by released calls by RRC Connection Reconfiguration T/O (SCell)

SCellAddFail_CaCapaCac

Number of fails in SCell addition under Carrier Aggregation Capability CAC Procedure (SCell)

SCellAddFail_CpCcFail

Number of fails in Scell Addition under ECCB (Scell)

SCellAddFail_CpRrmFail

Number of fails in Scell Addition due to resource allocation failure (Scell)

SCellRel_RrcSig

Number of times that SCell Release is performed under the RRC connection reestablishment procedures (SCell)

SCellRel_HoOut

Number of times that SCell Release is performed under the HO Out procedures (SCell)

SCellRel_EventA2

Number of times that SCell Release is performed by Event A2 (SCell)

SCellRel_EventA6

Number of times that SCell Release (Change) is performed by Event A6 (SCell)

SCellRel_RrcResetup

Number of times that SCell Release is performed under the RRC connection reestablishment procedures (SCell)

SCellRel_CaCac

Number of times that SCell Release is performed under the Carrier Aggregation CAC (SCell)

SCellAddCnt_Avg

The average number of SCell Added UEs.

SCellAddAtt_RrcSig

The number of attempt to Add Scells during attach

SCellAddAtt_HoIn

The number of attempt to add Scells during Handover In

SCellAddAtt_EventA4

The number of attempt to add Scells triggered by A4 Event MR

SCellAddAtt_EventA6


SCellAddAtt_RrcResetup

The number of attempt to add Scells triggered by rrcConnectionReestablishment

SCellRel_SbcPriority

The number of attempt to release existed Scells because of adding new Scell of SBC with high priority

SCellAddAtt_AddSbcRrcSig

The number of attempt to Add Scells during


272


Carrier Aggregation Message count for Activation/Deactivation (SCell)

Type Name

Type Description attach after getting additional SBC

SCellAddAtt_AddSbcHoIn

The number of attempt to add Scells during Handover In after getting additional SBC

SCellAddAtt_AddSbcRrcRes etup

The number of attempt to add Scells triggered by rrcConnectionReestablishment after getting additional SBC

SCellAddSucc_AddSbcRrcSi g

The number of success to add Scells during attach after getting additional SBC

SCellAddSucc_AddSbcHoIn

The number of success to add Scells during Handover In after getting additional SBC

SCellAddSucc_AddSbcRrcR esetup

The number of success to add Scells triggered by rrcConnectionReestablishment after getting additional SBC

SCellRel_AddSbcRrcSig

The number of attempt to release existent Scells because of adding new Scells after getting additional SBC during attach procedure

SCellRel_AddSbcHoIn

The number of attempt to release existent Scells because of adding new Scells after getting additional SBC during Handover In procedure

SCellRel_AddSbcRrcResetu p

The number of attempt to release existent Scells because of adding new Scells after getting additional SBC during RRC Reestablishment procedure

SCellAddAtt_AddSbcRrcSig

The number of attempt to Add Scells during attach

SCellRel_AddSbcHoIn

The number of attempt to add Scells during Handover In

SCellRel_AddSbcRrcResetu p


SCellActivation

Count of activations (SCell)

SCellDeactivation_TO

Count of SCell deactivation occurrences by reason: When deactivation timer expires (SCell)

SCellDeactivation_Mismatch

Count of SCell deactivation occurrence by reason: When CA status of eNB and that of the UE are different (SCell)

CRNTIcollision

The cumulated number of Scell Activation fail due to C-RNTI collision (The C-RNTI of UE, who requests Scell activation to SCell, is already used in SCell)

SCellActUEAvg

The average number of Scell activated UE

SCellActivationAtt

The cumulated number of Scell Activation Attempts.

SCellActFailCaCac

The cumulated number of Scell Activation Failures due to CA CAC Fail.

SCellActFailSCellSetupTime Out

The cumulated number of Scell Activation Failures due to not receiving the response to Scell Setup within predefined time from eNB.

SCellActFailActMacCeResBl

The cumulated number of Scell Activation


273


Type Name er

Type Description Failures due to that Residual BLER occurs about Activation MAC CE Transmission.

Air MAC Packet (PCell)

AirMacULByte

The sum of the size of the MAC PDU successfully received via PUSCH during the statistics period

AirMacULByteCnt

AirMacULByte collection count

AirMacULTti

The sum of sections that have the MAC PDU successfully received via PUSCH during the statistics period

AirMacULThruAvg

Average size per second of the MAC PDU successfully received via PUSCH

AirMacULEfctivThruAvg

Average size of the MAC PDU of the section successfully received via PUSCH during the statistics period

AirMacDLByte

The sum of the size of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

AirMacDLByteCnt

AirMacDLByte collection count

AirMacDLTti

The sum of sections that have the MAC PDU successfully transmitted via PDSCH during the statistics period

AirMacDLThruAvg

Average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

AirMacDLEfctivThruAvg

Average size of the MAC PDU of the section successfully transmitted via PDSCH during the statistics period

AirMacULByteCurr

The most recently collected AirMacByteUl value

AirMacDLByteCurr

The most recently collected AirMacDLByte value

AirMacULThruMin

Minimum of the average size per second of the MAC PDU successfully received via PUSCH

AirMacULThruMax

Maximum of the average size per second of the MAC PDU successfully received via PUSCH

AirMacDLThruMin

Minimum value of average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

AirMacDLThruMax

Maximum value of average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

AirMacULByte


AirMacULByteCnt


AirMacULTti

The sum of sections that have the MAC PDU

Air MAC Packet (SCell)


274


DL Wideband CQI (PCell)

Type Name

Type Description successfully received via PUSCH during the statistics period.

AirMacULThruAvg

Average size per second of the MAC PDU successfully received via PUSCH.



AirMacDLByte


AirMacDLByteCnt


AirMacDLTti


AirMacDLThruAvg




AirMacULByteCurr


AirMacDLByteCurr


AirMacULThruMin


AirMacULThruMax


AirMacDLThruMin


AirMacDLThruMax


DLReceivedCQI0

Number of receiving CQI 0 for a wideband CQI per layer/codeword transmitted from CA UE whose the cell is PCell

DLReceivedCQI1


DLReceivedCQI2


DLReceivedCQI3



275


DL Wideband CQI (SCell)

Type Name

Type Description

DLReceivedCQI4


DLReceivedCQI5


DLReceivedCQI6


DLReceivedCQI7


DLReceivedCQI8


DLReceivedCQI9


DLReceivedCQI10


DLReceivedCQI11


DLReceivedCQI12


DLReceivedCQI13


DLReceivedCQI14


DLReceivedCQI15


DLReceivedCQIMin

The minimum value of DlReceivedCQI received from CA UE whose cell is PCell

DLReceivedCQIMax

The maximum value of DlReceivedCQI received from CA UE whose cell is PCell

DLReceivedCQIAvg

The average value of DlReceivedCQI received from CA UE whose cell is PCell

CQIErase

Number of times that CQI erase per layer/codeword is received from CA UE whose cell is PCell

DLReceivedCQI0

Number of receiving CQI 0 for a wideband CQI per layer/codeword transmitted from CA UE whose the cell is SCell

DLReceivedCQI1


DLReceivedCQI2

Number of receiving CQI 2 for a wideband


276


Type Name

Type Description CQI per layer/codeword transmitted from CA UE whose the cell is SCell

DLReceivedCQI3


DLReceivedCQI4


DLReceivedCQI5


DLReceivedCQI6


DLReceivedCQI7


DLReceivedCQI8


DLReceivedCQI9


DLReceivedCQI10


DLReceivedCQI11


DLReceivedCQI12


DLReceivedCQI13


DLReceivedCQI14


DLReceivedCQI15


DLReceivedCQIMin

The minimum value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

DLReceivedCQIMax

The maximum value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

DLReceivedCQIAvg

The average value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

CQIErase

Number of times that CQI erase per layer/codeword is received from CA UE


277


Type Name

Type Description whose cell is SCell

CA UE per number of CC

DL_1FD_SCC

The average number of UEs that has one of FDD DL carrier to SCell.

DL_1TD_SCC

The average number of UEs that has one of TDD DL carrier to SCell.

DL_2FD_SCC

The average number of UEs that has two of FDD DL carriers to SCell.

DL_2TD_SCC

The average number of UEs that has two of TDD DL carriers to SCell.

DL_1FD_1TD_SCC

The average number of UEs that has one of FDD DL carrier and one of TDD DL carrier to SCell.

No_DlCaCapabilityUe

There is no CA capability corresponding to the supportedBandCombination

2CC_DlCaCapabilityUe

CA capability corresponding to the supportedBandCombination support 2 Component Carrier

3CC_DlCaCapabilityUe

CA capability corresponding to the supportedBandCombination support 3 Component Carrier

2CC_ScellAdditionTime

Total SCell Addition Time of 2 Component Carrier

3CC_ScellAdditionTime

Total SCell Addition Time of 3 Component Carrier

SCell Added Information (PCell)

REFERENCE [1] 3GPP TS 36.101 „Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception‟ [2] 3GPP TS 36.300 „Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2‟ [3] 3GPP TS 36.331 „Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification‟


278

Chapter 3

Load Control

LTE-SW2001, Intra-LTE Mobility Load Balancing INTRODUCTION Samsung intra-LTE Mobility Load Balancing (MLB) enables an eNB to release the overload of a cell or to maintain the cell load difference between the co-located inter-frequency cells within the range set by an operator. For intra-LTE MLB, the eNB periodically monitors the cell load status of its own cells and neighbor cells. If the served cell‟s load reaches the threshold value and neighbor cell is low loaded, the eNB relocates some selected UEs from a higherloaded cell to lower-loaded neighbor cells.

BENEFIT 

By distributing traffic over multiple carriers, good QoS can be provided for each carrier.

The Quality of Experience (QoE) felt by the user can be improved.

DEPENDENCY 

Interface and Protocols X2 Interface: The eNBs should support X2 Resource Status Reporting so that the cell-load information can be exchanged between neighbor cells via the X2 interface.



Others oUE capability: Only UEs that support multiple carriers in the operator network are selected as candidates for load balancing between carriers. oCo-existence with Smart SON Tx Power Control (LTE-SO2021): It is recommended that A3 measurement for intra-frequency MLB should be turned off since Smart SON TPC periodically modifies the DL Tx power for load balancing between intra-frequency cells.

LIMITATION Conditions for Load Equalization: Load equalization is available only when the inter-frequency co-located neighbor cell supports a carrier of the same carrier group and its attribute isColocated in NRT is set to true.


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Chapter 3 Load Control

SYSTEM IMPACT Performance The Intra-LTE MLB feature performs gradual reduction of overload traffic by moving configured rate of UEs to neighbors in every period (configurable: few seconds). The amount of offloaded traffic at each period can be adjusted by configuring related parameters (RATE_LB_CANDIDATE and RATE_LB_TARGET. Coverage The Intra-LTE MLB feature uses the dedicated A3/A4 event parameter setting for MLB. The thresholds such as a3Offset and a4ThresholdRSRP (or RSRQ) can affect the area where MLB-triggered HOs occur.

FEATURE DESCRIPTION This section describes various methods supported by Samsung eNB for load balancing.

Intra-LTE MLB Functions and Carrier Grouping Samsung Intra-LTE MLB feature works based on carrier groups. Carriers must be configured into one or more carrier groups based on the operator‟s radio spectrum management policy. For example, the operator can manage a few lower frequency carriers as the VoLTE-preferred carriers or the operator can manage a few carriers for RAN sharing with other operator. In these cases, the carriers for a specific purpose need to be configured into a same carrier group. This feature consists of the following three types of load balancing functions, which can be enabled or disabled at the cell level:

Load equalization within intra-group carriers The purpose of this function is to maintain the cell load difference between a source cell and a co-located inter-frequency neighbor cell within the configured threshold level. Only the co-located neighbor cells of the same carrier group are candidate cells for this function.

Offloading to intra-group carriers The purpose of this function is to reduce a source cell‟s load by using lowerloaded intra-frequency and inter-frequency neighbor cells that belong to the same carrier group.

Offloading to inter-group carriers The purpose of this function is to reduce a source cell‟s load by using lowerloaded inter-frequency neighbor cells that belong to a different carrier group. Figure below depicts three types of intra-LTE MLB functions that can be activated according to the load level of the source cell. Load equalization within intra-group carriers is inactivated when offloading to intra-group carriers is activated. However, offloading to intra-group carriers still work when offloading to intergroup carriers is activated. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Figure below depicts an example of how intra-LTE MLB functions offload UEs to neighbor cells based on carrier grouping.

Procedure of Intra-LTE MLB Functions Figure below depicts the brief procedure of intra-LTE MLB.


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1 When any of the intra-LTE MLB functions is turned on, the eNB monitors the load levels of its cells and neighbor cells periodically.

2 If a source cell exceeds a configured threshold for one of the intra-LTE MLB functions, the corresponding intra-LTE MLB function is activated. However, load equalization within intra-group carriers is activated only if the cell load difference between the source cell and its co-located inter-frequency cell also exceeds a configured level.

3 The eNB selects a configured rate of candidate UEs randomly and configures measurements for the purpose of load balancing.

4 After the eNB collects measurement reports from candidate UEs, it selects the configured rate of target UEs to be moved to target cells. Pairs of (target UE, target cell) are selected based on the target cell‟s load and reported signal strength.

5 The eNB performs handovers of the target UEs to the target cells. Figure below shows the call flow of intra-LTE MLB. The details for each step are described in the following sub-sections.


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Cell Load Monitoring When any of the intra-LTE MLB functions for a source cell is turned on, the eNB monitors the load levels of the source cell and its neighbor cells periodically. The eNB monitors the source cell‟s load with the period of T_LOAD_DECISION_LB and neighbor cells‟ load with the period of T_RESOURCE_STATUS_REPORTING. If only load equalization within intra-group carriers is turned on, the source cell selects the intra-group inter-frequency neighbors, which have the attribute IS_COLOCATED set to TRUE. When offloading to intra-group carriers or offloading to inter-group carriers is turned on and the source cell has no existing cell load report from neighbor cells, the eNB selects the:

Configured number (NUM_OF_NR_FOR_ACTIVE_LB) of high-ranked neighbor cells in each carrier

Co-located inter-frequency neighbors in the intra-group. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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If there is any existing cell load report from at least one neighbor cell, then the process of selecting neighbors are performed at the next time of ANR ranking. The neighbors are ranked based on the number of HO successes in the period of NR_RANKING_PERIOD. To monitor the selected inter-eNB neighbor cells‟ load, the eNB uses X2 Resource Status Reporting procedure. A source eNB sends X2 Resource Status Request message to a neighbor eNB to which a selected neighbor cell belongs. The X2 Resource Status Request message includes the following information:



Report Characteristic IE: Samsung eNB requests the Composite Available Capacity Group IE so that it can estimate a neighbor cell‟s load from the DL/UL Capacity Value IEs (as described in Cell Load Metric).



Reporting Periodicity IE: The Reporting Periodicity IE is determined by the T_RESOURCE_STATUS_REPORTING.

When the neighbor eNB receives the X2 Resource Status Request message and can report the Composite Available Capacity Group IE, it:

Sends the X2 Resource Status Response message. Reports the cell load information periodically by using the X2 Resource Status Update message.

Decision on MLB Activation Three types of intra-LTE MLB functions are activated by different threshold levels:

Load equalization within intra-group carriers The load equalization is activated if the source cell load exceeds EQUAL_THRESHOLD (k) (k = 0, 1, 2, 3) and the cell load difference between the source cell and its co-located intra-group inter-frequency neighbor cell exceeds EQUAL_DELTA (k) (k = 0, 1, 2, 3). The co-located inter-group inter-frequency neighbor is not considered for load equalization. The number of levels for load equalization can be controlled from 1 to 4 by setting NUM_EQUAL_STEP. The following relations must be maintained irrespective of NUM_EQUAL_STEP when changing the thresholds below: oEQUAL_THRESHOLD0 ≤ EQUAL_THRESHOLD1 ≤ EQUAL_THRESHOLD2 ≤ EQUAL_THRESHOLD3 ≤ INTRA_GROUP_OFFLOAD_THRESHOLD [Inequation 1] oEQUAL_DELTA3 ≤ EQUAL_ DELTA2 ≤ EQUAL_ DELTA1 ≤ EQUAL_DELTA0 [Inequation 2]


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Figure below depicts an example of how the values are set in load equalization. Since both the source cell‟s load and the load difference at the point A exceed the configured thresholds, the load equalization is activated. In this example, point A is moved to the point B by the action of load equalization. At point B, the source cell load exceeds the EQUAL_THRESHOLD (0, however, the load difference does not exceed the EQUAL_DELTA (0). Therefore, the load equalization is not activated.

Offloading to intra-group carriers Offloading to intra-group carriers is activated if the source cell load exceeds INTRA_GROUP_OFFLOAD_THRESHOLD. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Offloading to inter-group carriers To enable offloading to the pth carrier group, both INTER_GROUP_OFFLOADING_ ENABLE for the source cell and OFFLOADING_TO_THIS_INTER_GROUP_ENABLE at the pth carrier group in the source eNB need to be set to ON. When multiple carrier groups are configured, the threshold for offloading to a specific carrier group from any other can be set separately. Offloading to the pth carrier group is activated if the source cell load exceeds INTER_GROUP_OFFLOADING_THRESHOLD at the pth carrier group.

Configuring Measurements for Candidate UEs The eNB selects the candidate cell based on the activated MLB function. These are the selection procedures:



Load equalization within intra-group carriers: A co-located intra-group interfrequency cell, which meets the cell load difference condition, is determined as a candidate cell.



Offloading to intra-group carriers: An intra-group intra-/inter-frequency neighbor cell, whose cell load is less than [source cell‟s loadDELTA_OFFLOAD_THRESHOLD], is determined as a candidate cell. A colocated intra-group inter-frequency neighbor cell is also included for offloading to intra-group carriers.



Offloading to inter-group carriers: An inter-group inter-frequency neighbor cell, whose cell load is less than [source cell‟s loadDELTA_OFFLOAD_THRESHOLD] and serves a frequency of the pth carrier group, is determined as a candidate cell.

If USE_TRAFFIC_PER_UE is set to USE, the source cell selects UEs with higher downlink PRB usage grade as candidate UEs up to the configured rate (RATE_LB_CANDIDATE). In this case, UEs are periodically graded according to their downlink per-UE PRB usage. Otherwise, the source cell randomly selects candidate UEs up to the configured rate. The source cell provides them the measurement configuration on the frequencies of the candidate cells, through the RRC Connection Reconfiguration message. It starts the timer (T_MEASUREMENT_COLLECTION_LB) for collecting measurement reports. If the source cell receives measurement reports from all the candidate UEs or the timer expires, then it starts selecting (target UE, target cell) pairs. UEs with CA capability can be selected as the candidate UE if they are not SCellactivated. If CA_UE_CANDIDATE_FLAG is Ci_ON, a SCell-activated UE can be selected as the candidate UE.


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For the intra-frequency measurement, the event A3 with the purpose index CI_A3PURPOSE_INTRA_FREQUENCY_LB is configured. To get the region for intra-frequency MLB, A3OFFSET for the MLB HO purpose should be set to less than the normal intra-frequency HO purpose. For the inter-frequency measurement, the event A4 with the purpose index CI_A4PURPOSE_INTER_FREQUENCY_LB is configured. When the measurement report is received from the UE and the reported strongest neighbor in a frequency is one of the candidate cells, the pair of the UE and the strongest neighbor cell can be the candidate pair for load-balancing handover.

Selecting {target UE, target cell} Pairs The eNB selects the strongest pairs, target UE, and cell, among the candidate pairs. To do this, the eNB uses the following methods:

Selects the candidate cell with the lowest cell load among the reported strongest neighbors for each candidate UE.

Selects {target UE, target cell} pairs until the ratio of the selected target UEs to the RRC connected UEs approaches the configured rate (RATE_LB_TARGET) with the criterion of the lowest cell load. After selecting {target UE, target cell} pairs, the source eNB performs X2 handover procedure, where the Cause IE in the X2 Handover Request message will be set to Reduce Load in Serving Cell. Figure below depicts how the {target UE, target cell} pairs are selected.


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Blind Mode in Offloading to Inter-group Carriers In offloading to inter-group carriers, if OFFLADING_TO_THIS_INTER_GROUP_ENABLE at the pth carrier group is set to LB_BLIND, the source eNB does not send the X2 Resource Status Request messages to the inter-eNB neighbors at the carriers of the pth carrier group. The source eNB uses source cell‟s load - DELTA_OFFLOAD_THRESHOLD -1 as the fixed cell load for these neighbors. The other procedure is same as that described above. When the candidate UE reports multiple carriers of the pth carrier group and it is selected as the target UE, its target cell will be selected in a stochastic manner. The probability of the target carrier is proportional to the corresponding CELL_CAPACITY_CLASS_VALUE_DL_PER_FA in the management object EutraFaPriorInfoFunc.

Call Admission Control on Load-based HO When the target eNB receives the X2 Handover Request message with the Cause IE set to Reduce Load in Serving Cell, it sends the X2 Handover Request Acknowledge message. This message is sent only if the requested target cell‟s load is smaller than TARGET_CELL_LOAD_THRESHOLD. Otherwise, the target eNB sends the X2 Handover Preparation Failure message.

Cell Load Metric Samsung intra-LTE MLB feature provides two modes for cell load evaluation:



LOAD_PRB mode: Only DL and UL PRB usages are factored in cell load evaluation.



LOAD_TOTAL mode: The DL and UL PRB usages, CPU usage, backhaul usage, and the number of RRC connected UEs are factored in cell load evaluation.

The cell load for the time window index i is given by:

The DL and UL bar{Load_{total}}(i) for the time window index i are updated respectively every PRB_REPORT_PERIOD by an exponential moving average as follows.

Here, alpha is the filtering coefficient and Load^{*}_{mode}(i) is calculated according to the selected cell load evaluation mode. The eNB checks whether the source cell‟s load exceeds a configured threshold for one of enabled intra-LTE MLB functions with the period of T_LOAD_ DECISION_LB while it updates the source cell‟s load every PRB_REPORT_PERIOD.


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LOAD_PRB Mode When LOAD_EVALUATE_MODE is set to LOAD_PRB, Load^{*}_{mode}(i) is evaluated as follows. In this mode, DL and UL Load^{*}_{mode}(i) are equal to DL and UL PRB load Load_{PRB}(i) respectively. DL and UL PRB load are evaluated as:

The loads due to control channels and GBR bearers are calculated as the control PRB usage and the GBR PRB usage as follows:

The load due to non-GBR bearers is calculated as:

Here, the non-GBR bearers load QCI = q, Load_{NGBR,q} is calculated as: For q = 5, 6, .., 9,

Where:



min {a, b} indicates the minimum between a and b.



CBR_{q} is the configured bit rate for a non-GBR QCI = q bearer.(Configurable parameter: CONFIGURED_BIT_RATE) Here, the configured bit rate can be set to the expected average bit rate for a non-GBR QCI = q bearer.



W indicates the time window length (= 1 sec).



N_{q} (i) is the number of active bearers during the time window index i.



w_{q} is the weight factor for the non-GBR QCI = q.(Configurable parameter: CONFIGURED_BIT_RATE)

For the other non-GBR QCIs (q = 10, 11, …),

To reduce the computational load of DSP, the load formula for the other non-GBR QCIs is simplified. The padding PRB usage indicates the percentage of the PRBs which include only the padding bits. It is calculated as follows. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The load due to padding PRB usage is calculated as:

Where: o

estimated_PRB_{padding, GBR} indicates the estimated padding PRB usage caused by GBR bearers, and is calculated as follows.

oestimated_PRB_{padding, NGBR} indicates the estimated padding PRB usage caused by non-GBR bearers, and is calculated as follows:

LOAD_TOTAL Mode When LOAD_EVALUATE_MODE is set to LOAD_TOTAL, DL and UL Load^{*}_{mode}(i) are evaluated as:

Where:



max {a, b} indicates the maximum between a and b.



intraGroupOffloadThreshold indicates INTRA_GROUP_OFFLOAD _THRESHOLD, which is the threshold for offloading to intra-group carriers.



Condition A is met if one of these conditions is true: o(C1): The number of RRC_Connected_UEs in a serving cell exceeds the configured threshold (CAPACITY_LB_ALPHA_FACTOR ×NUM_LB_MAX_UE)

o(C2): The CPU load exceeds the configured threshold (CPU_THRESHOLD)

o(C3): The backhaul load exceeds the configured threshold. In other words, the assignable backhaul capacity is less than the configured threshold (MIN_BACK_HUAL_CAPACITY).


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Capacity Value DL and UL capacity values indicate the DL and UL Capacity Value IEs of Composite Available Capacity IE in X2 Resource Status Update message. The DL or UL capacity value is evaluated as:

Cell Load Difference Cell load difference in load equalization is calculated as:

Here, the cell load of a neighbor cell is given by:


How to Activate Preconditions There are no specific preconditions to activate this feature. Activation Procedure You can use only one of MLB modes among LOAD_EQUALIZATION_ENABLE, INTRA_GROUPOFF_LOAD_ENABLE, and INTER_GROUPOFF_LOADING_ENABLE. To activate this feature, do the following:

Run CHG-LBGRP-CONF/RTRV-LBGRP-CONF to configure carrier groups. Run CHG-ACTIVE-LB/RTRV-ACTIVE-LB to set the related parameters. Run CHG-LBGRP-CONF/RTRV-LBGRP-CONF to configure the OFFLADING_TO_THIS_INTER_GROUP_ENABLE threshold for offloading to inter-group carriers.

Run CHG-NBR-EUTRAN/RTRV-NBR-EUTRAN to configure the co-located inter-frequency neighbors for load equalization within intra-carrier group.

Run CHG-TM-CNTR/RTRV-TM-CNTR to enable the selected intra-LTE MLB functions: LOAD_EQUALIZATION_ENABLE, INTRA_GROUPOFF_LOAD_ENABLE, and INTER_GROUPOFF_LOADING_ENABLE to ON. For offloading to the pth eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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inter-group carriers, OFFLADING_TO_THIS_INTER_GROUP_ENABLE at the pth carrier group is also set to lb_ON. Deactivation Procedure To deactivate this feature, set LOAD_EQUALIZATION_ENABLE, INTRA_GROUPOFF_LOAD_ENABLE, and INTER_GROUPOFF_LOADING_ENABLE to OFF.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated command and set the key parameters. Parameter Descriptions of CHG-TM-CNTR/RTRV-TM-CNTR Parameter

Description

LOAD_EQUALIZATION_ENAB LE

This parameter configures whether to execute the LOAD_EQUALIZATION step during active mode load balancing.

INTRA_GROUP_OFFLOAD_EN ABLE

This parameter configures whether to execute the INTRA_GROUP_OFFLOADING step during active mode load balancing.

INTER_GROUP_OFFLOAD_EN ABLE

This parameter configures whether to execute the INTER_GROUP_OFFLOADING step during active mode load balancing.

Configuration Parameters To configure the feature settings, run the associated command and set the key parameters. Parameter Descriptions of CHG-LBGRP-CONF/RTRV-LBGRP-CONF Parameter

Description

GRP_FA0

This parameter configures the EARCFN_DL value of a FA, which is specified by a specific group ID. If it is not configured, enter 0.

GRP_FA1


GRP_FA2


GRP_FA3


OFFLADING_TO_THIS_INTE R_GROUP_ENABLE

This parameter decides whether enabling or disabling INTER_GROUP_OFFLOADING to the FA group that belongs to a specific group ID.

INTER_GROUP_OFFLOADING _THRESHOLD

This parameter configures threshold of serving cell load to perform INTER_GROUP_OFFLOADING to a FA group belong to the group ID.

Counters and KPIs Table below outlines the main counters associated with this feature.


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Chapter 3 Load Control Family Display Name

Type Name

Type Description

LOAD

LoadIndicatorAvg

Average load of a cell when overload occurs due to the MLBO operation.

LoadIndicatorMin

Minimum load of a cell when overload occurs due to the MLBO operation.

LoadIndicatorMax

Maximum load of a cell when overload occurs due to the MLBO operation.

LoadIndicatorTot

Accumulated load of a cell when overload occurs due to the MLBO operation

LoadIndicatorCnt

The number of LoadIndicatorAvg called.

OverloadCount

The number of overload occurrences due to the MLBO operation.

MlbDurationAvg

Average of the overload period due to the MLBO operation.

MlbDurationMin

Minimum value of the overload period due to the MLBO operation.

MlbDurationMax

Maximum value of the overload period due to the MLBO operation.

MlbDurationTot

Accumulated value of the overload period due to the MLBO operation.

MlbDurationCnt

The number of MlbDurationAvg called.

MlbNotTriggered_Load Condition

The number of times when there is no candidate neighbor cell that meets the load condition although MLB is triggered.

MlbNotTriggered_Radio Condition

The number of times when there is no candidate UE because radio condition is not met although MLB is triggered.

MlbHOAtt

The number of handover attempts when MLB is triggered.

MlbHOSucc

The number of successful handovers when MLB is triggered.

LbhoCnt

Load Balancing handover collection count.

LbhoCid

tcID of which collection is requested.

LOAD_HISTOGR AM

LoadBinAvg

Cumulative LoadBinAvg.

LoadBinCnt

LoadBinAvg collection count.

LBHO_KPI

InterEnbHoSuccRatio

Inter-eNB Load Balancing Handover Success Rate.

SumInterEnbMlbHoAtt

Sum of MlbHOAtt that satisfy the condition of InterEnb.

SumInterEnbMlbHoSuc c

Sum of MlbHOSucc that satisfy the condition of InterEnb.

IntraEnbIntraCarrierGro upHoSuccRatio

Intra-eNB Load Balancing Handover Success Rate to a separate carrier within the same eNodeB of the same frequency due to load balancing.

SumIntraEnbIntraCarrie rGroupMlbHoAtt

Sum of MlbHOAtt that satisfy the condition of IntraEnbIntraCarrierGroup.

SumIntraEnbIntraCarrie rGroupMlbHoSucc

Sum of MlbHOSucc that satisfy the condition of IntraEnbIntraCarrierGroup.

IntraEnbInterCarrierGro upHoSucRatio

Intra-eNB Load Balancing Handover Success Rate to a separate carrier within the same eNodeB of the different carrier group due to load balancing.

SumIntraEnbInterCarrie rGroupMlbHoAtt

Sum of MlbHOAtt that satisfy the condition of IntraEnbInterCarrierGroup.

SumIntraEnbInterCarrie rGroupMlbHoSucc

Sum of MlbHOSucc that satisfy the condition of IntraEnbInterCarrierGroup.

LBHO


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REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification [3] 3GPP 36.423: E-UTRAN; X2 application protocol (X2AP) [4] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions


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LTE-SW2020, Load Distribution over Backhaul Links INTRODUCTION When eNB is connected to a backhaul network with multiple Ethernet links, there are different ways to distribute load over the links depending on IP configuration. For example, when single IP address is used for two Ethernet links in the same subnet, link aggregation can be used for load balancing between two links. In order to forward a packet, one link is selected by a hashing algorithm based on 5 tuples of the packet. When one link fails, the other link carries all the packets. In this case, however, SCTP multi-homing for S1/X2 interface cannot be used because there is only one IP address available. Equal Cost Multi Path (ECMP) is another way to achieve load balancing between two links that has two different IP addresses belonging to different subnet. In this case, however, it is not likely to evenly distribute load over the links because most packets will have the same source and destination IP and port number. In this feature, application layer selects a link during call setup procedures based on the number of UEs per each link. Traffic from a UE is carried over the same link. SCTP multi-homing can be enabled at the same time and even load distribution is achieved in terms of the number of UEs.

BENEFIT Load balancing achieved between two links. Operator can monitor all the traffic of a specific UE on the same link.

DEPENDENCY This feature can be enabled when eNB has two available Ethernet links.

LIMITATION This feature is not working with IPsec or Virtual Routing enabled For this feature, routes on each link should be configured as ECMP

FEATURE DESCRIPTION For load balancing between backhaul links that are connected to an eNB, we assume that the backhaul network shall be configured to support the separated two links, and front-end switches (or routers) in different path shall be connected to each other in order to secure an emergency path in case of link failure. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Load balancing between backhaul links Before eNB sends INITIAL CONTEXT SETUP RESPONSE message during the UE's call setup procedures, the eNB selects a link that has lower load in terms of the number of UEs, and include the transport network layer address in the message. As a result, the eNB will use the selected IP address as a source address of uplink GTP tunnel and as a destination address of downlink GTP tunnel for the UE. Since load is distributed based on the number of UEs, we cannot guarantee that actual amount of traffic is equalized between two links. The packets coming from the same UE and the packets heading to the same UE are carried through the same link. Therefore, operator can monitor all the packets from/to one UE by tapping the one link. Note that signaling messages(S1, X2) follow SCTP rules.

Link Failure When eNB detects a failure on one link, it sends GARP message through the other link so that the switches (or routers) can forward packets by using a live path. Otherwise, the packets would not be forwarded to the eNB in downlink path. For uplink packets, eNB forwards them to the healthy link.

SYSTEM OPERATION How to Activate When the eNB equips with two Ethernet links and they are both active, it starts to distribute calls over two links. When one link becomes not available, the eNB forwards all the packets to the other link available. There is no handler that operator can enable or disable this feature.




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REFERENCE None


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LTE-SW2104, eNB Overload Protection INTRODUCTION This feature explains how an eNB can be protected from being overloaded by limiting the number of calls during a given time period. Integrated eNB provides a function that can limit the maximum count of call connection requests (RRC connection request) per unit time.

BENEFIT This feature helps eNB from being overloaded by configuring the threshold settings.

DEPENDENCY None

LIMITATION The UE may experience a long setup time in case of congestion

FEATURE DESCRIPTION This feature enables operator to configure the monitoring duration for eNB overload protection. The maximum number of request messages for each RRC establishment cause and PS paging is shown below.

The maximum number of highPriorityAccess calls The maximum number of mo-Signaling calls The maximum number of mo-Data calls The maximum number of delayTolerantAccess The maximum number of PS paging (if include paging priority IE, then the eNB will not discard the paging message) See RRC establishment causes in RRCConnectionRequest message. emergency and mt-Access calls are not limited. EstablishmentCause ::= ENUMERATED { emergency, highPriorityAccess, mt-Access, mo-Signalling, mo-Data, delayTolerantAccess-v1020, spare2, spare1}

The eNB operation is as follows: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1 eNB observes the number of call request per RRC establishment cause and the number of PS paging for the monitoring time which is specified in the system parameter.

2 If the count exceeds the maximum number of call requests for establishment cause or PS paging message, then the eNB will discard the call.

3 When the monitoring time expires, the eNB initializes all counters for RRC establishment causes and PS paging messages. Then eNB begins to count up during the next monitoring time period. When the counter reaches the configured maximum limit, the eNB discards any additional request messages. A detailed overview of the operation procedure is shown below.

Operation Procedure Establishment Cause Based Protection Procedure The maximum count of call connection requests per unit time can be set as a system parameter for each RRC establishment cause. However, if the RRC establishment cause is an emergency and mt-Access, this number cannot be set.

The integrated eNB monitors the number of call connection requests for each RRC establishment cause during the monitoring period set by the system parameter.

When an RRC Connection Request message is received from the UE, if the number of call connection requests has not exceeded the threshold corresponding to the RRC establishment cause included in the RRC Connection Request message, the call connection request is accepted; however, if the count exceeds the threshold, the call connection request is not accepted.

If the monitoring period set by the system parameter has expired, the integrated eNB initializes the count of call connection requests for each RRC establishment cause.

The RRC establishment cause can be used by the network to prioritise the connection establishment request from the UE at the high load situation in the network. Paging Based Protection Procedure The maximum count of paging processes per unit time can be set as a system parameter.

The number of paging requests is monitored during the monitoring period set by the system parameter.

If the number of paging requests received from the MME has not yet exceeded the threshold, the paging message is processed; if the number exceeds the threshold, further paging requests are ignored.

If include paging priority IE received from the MME, then the eNB will not discard the paging message.

If the monitoring period set by the system parameter has expired, the paging request count is initialized. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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SYSTEM OPERATION How to Activate Overload Protection (CALL): change the overload protect control mode with CHG-OVLD-PTC command oProtectPerNormalCall: number of Normal Call based Overload Protection (control 1) oProtectPerEstablishCause: Establish Cause based Overload Protection (control 2)

Overload Protection (psPaging): change the psPaginglProtectUsage to 'USE' with CHG-OVLD-PTC command

Key Parameters Parameter

Description

OVERLAOD_PROTECT_CT RL

Setting Value for Overload Protect. 0: noUse 1:ProtectPerNormalCall 2:ProtectPerEstablishCause

PS_PAGING_PROTECT_U SAGE

Whether to execute psPaging Protect function


Type Name

Type Description

DENIED_CALL

Denied_HighPriorityAccess

Number of high priority access-type calls denied by the overload protection function

Denied_moSignaling

Number of mo signaling-type calls denied by the overload protection function

Denied_moData

Number of mo data-type calls denied by the overload protection function

Denied_DelayTolerantAccess

Number of delay tolerant access calls denied by the overload protection function

Denied_Paging

Number of paging messages denied by the overload protection function

REFERENCE [1] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification


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LTE-SW2106, Delay Tolerant Access Processing for eNB Overload Control INTRODUCTION When RAN and Core network gets overloaded during peak traffic, traffic needs to be reduced. So, NAS and RRC signaling has to be minimized for low-priority UEs. RAN mechanism to reduce signaling is to reject RRC Connection Request message from low-priority UEs or to release existing RRC connections of lowpriority UEs. From 3GPP Release 10, low-priority UEs have to set Delay Tolerance Access bit in RRC Connection Request message. When the network is congested, eNB can reject or release RRC Connection with ExtendedWaitTime period. The UE can retry connecting to the network after the expiration of the ExtendedWaitTime period.

BENEFIT The eNB can reduce the amount of signaling in case of RAN & core network overload during network congestion.

The eNB can make effective use of available radio resources for high priority UEs

DEPENDENCY Dependency Low priority UEs (Rel.10) need to implement a DelayTolerantAccess as part of the EstablishmentCause parameter which is sent in RRCConnection Setup message.

The MME should support 3GPP Rel.10 S1 interface.

LIMITATION None


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FEATURE DESCRIPTION RAN and core network can be overloaded during peak traffic. When the network is congested, traffic needs to be reduced and eNB should make effective use of available radio resources. In order to use resources effectively during peak traffic, the network needs to identify priority UEs for which resources are to be allocated. It is up to the scope of the operator to configure low-priority UEs like MTC (Machine Type Communication) and other devices. Once UEs are configured, overload control mechanism is as follows:

RAN Side Overload: 1) Low priority UEs configured by the operator inform eNB during RRC Connection Request procedures that they are delay tolerant access UEs by setting the parameter "EstablishmentCause = DelayTolerantAccess" as per 3GPP TS36.331. 2-3) When eNB detects congestion due to overload in capacity or air link or backhaul link, It responds with RRC Connection Reject during establishment of new connections. ENB while sending the Normal RRCConnection Release to low priority UE, sets the ExtendedWaitTime indicating to low priority UE to retry to Connect to Network after the expiry of the ExtendedWaitTime. 4-5) When eNB receives anymore RRC Connection Requests from Low-Priority UEs, eNB responds with RRC Connection Reject and Rejects those messages.


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Core Network Overload 1) Low priority UEs configured by the operator inform eNB during RRC Connection Request procedures that they are delay tolerant access UEs by setting the parameter "EstablishmentCause = DelayTolerantAccess" as per 3GPP TS36.331. 2) When the MME detects congestion due to overload in Core Network, It responds with Overload Start Message setting Reject Delay Tolerant Access in Overload action IE in Overload Response IE message (as per 36.413 spec) 3) The eNB after receiving the Overload message from MME, responds with RRC Connection Reject during establishment of new connections. The eNB while sending the Normal RRCConnection Release to low priority UE, sets the ExtendedWaitTime indicating to low priority UE to retry to Connect to Network after the expiry of the ExtendedWaitTime. 4-5) When the eNB receives anymore RRC Connection Requests from LowPriority UEs, eNB responds with RRC Connection Reject and Rejects those messages.

UE Scope RRCConnectionRequest-r8-IEs ::= SEQUENCE { ue-Identity InitialUE-Identity, establishmentCause EstablishmentCause,spare BIT STRING (SIZE (1)) } EstablishmentCause ::= ENUMERATED { emergency, highPriorityAccess, mt-Access, mo-Signalling, mo-Data, delayTolerantAccess-v1020, spare2, spare1}


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eNodeB SCOPE i) RRCConnectionReject-v1020-IEs ::= SEQUENCE { extendedWaitTime-r10 INTEGER (1..1800) OPTIONAL, -- Need ON nonCriticalExtension SEQUENCE {} OPTIONAL -- Need OP } RRCConnectionRelease-v1020-IEs ::= SEQUENCE { extendedWaitTime-r10 INTEGER (1..1800) OPTIONAL, -- Need ON nonCriticalExtension SEQUENCE {} OPTIONAL -- Need OP } extendedWaitTime Value in seconds for the wait time for Delay Tolerant access requests. ii) For Overload Detection in Capacity, Air Link Control and Backhaul Link Interfaces and System Parameters to control this feature, Please Refer to LTE-SW4101 Capacity based Call Admission Control and LTE-SW2103 UL Congestion Prevention for details.

Core Network -- MME Scope Overload Response IE IE/Group Name

Presence

Range

IE type and reference

Semantics description

CHOICE Overload Response

-

-

-

-

>Overload Action

-

-

-

-

>>Overload Action

M

9.2.3.20

-

Overload Action

M

ENUMERATED (Reject RRC connection establishments for non-emergency MO DT, Reject RRC connection establishments for Signalling, Permit Emergency Sessions and mobile terminated services only, …, Permit High Priority Sessions and mobile terminated services only, Reject delay tolerant access)

-

-

For system parameters to control this feature, refer to LTE-SW4101 Capacity based Call Admission Control and LTE-SW2103 UL Congestion Prevention for details.

SYSTEM OPERATION How to Activate When MME is overloaded, the call types to be blocked are transmitted to eNB through overload start message.

When overload occurs, it provides the function restricting connection of delayTolerantAccess call.

It rejects connection according to the ratio of the connection restriction per overload class.


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When it rejects delayTolerantAccess call, it is inserted extendedWaitTime in RRC_Connection_Reject message if the UE supports rel. 10.

Key Parameters RTRV-TIMER-INF/CHG-TIMER-INF Parameter

Description

EXTENDED_WAIT_TIME

This parameter is extended waitTime value for delayTolerantaccess call. It is the information to set waitTime of the call when the call, whose EstablishmentCause value is delayTolerantaccess in RrcConnectionRequest message, is rejected in eNB. The UE transmits RrcConnectionRequest again after extended waitTime. A sufficiently large value must be guaranteed for the extended waitTime-value of a delayTolerantaccess call to give a connection priority to another UE. This parameter is the second unit timer value, not like other timers (A default value is recommended). [Related Specifications] 3GPP TS 36.331 [6.2.2 RrcConnectioinReject]


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2. Release 10 & 11 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification. Release 10 & 11 [3] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access (E-UTRA); S1 Application Protocol (S1AP). Release 10 & 11


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LTE-SW2107, MME Overload Protection INTRODUCTION When MME or eNB recovers from failure/shutdown/reboot scenario, this feature prevents massive connection requests on MME.

BENEFIT Prevent the overload situation of MME when all MMEs or the entire network reboots.

DEPENDENCY None

LIMITATION This feature can limit the number of call attempts after eNB reboots, and some UEs can experience longer network access at that moment.

If LTE-SW2104 eNB Overload Protection feature not activate, the MME overload protection also does not work.

FEATURE DESCRIPTION This feature protects MME from an overload situation, by means of reducing total call attempt count. Possible Scenarios of this happening is when eNB reboots or when all S1 interface are out of service, then if any one of S1 interface comes up to in-service. Protective mechanism is implemented by reducing RRC attempt threshold to a fraction of Normal threshold level and thereafter advancing by some configurable fraction of threshold after every expiry of the periodic timer provided. This procedure is repeated until the RRC attempt threshold reaches the limit of normal threshold. For example, considering the following scenario when Normal threshold of RRC attempt per sec: 160

Startup threshold ratio: 50 % Time unit for increase: 60 sec Increase ratio: 10 % Corresponding RRC attempt threshold is as tabulated below in the chart. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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SYSTEM OPERATION How to Activate In order to activate MME overload protection, set mmeOverloadProtection to USE using CHG-OVLD-PTC.

Key Parameters RTRV-OVLD-PTC/CHG-OVLD-PTC Parameter

Description

mmeOverloadProtection

This parameter indicates whether to perform MME overload protection for s1 signaling.

mmeOverloadStartupControl Threshold

This parameter is the threshold approved after first time of which at least S1 connection is set up with the MME. (%)

mmeOverloadstartupStepTi me

This parameter is the increasing unit time ratio gradually in MME overload protection function. (sec)

mmeOverloadStartupIncreas ePortion

This parameter is the increasing threshold ratio gradually in MME overload protection function. (%)


Type Name

Type Description

Denied Call by Overload Protection

Denied_HighPriorityAccess

The number of Priority Access calls that are denied due to the overload prevention function

Denied_moSignaling

The number of MO Signaling calls that are denied due to the overload prevention function


307

Chapter 3 Load Control Family Display Name

Type Name

Type Description

Denied_moData

The number of MO Data calls that are denied due to the overload prevention function

Denied_DelayTolerantAccess

The statistics that counts the number of DelayTolerantAccess calls that are denied due to the overload prevention function

REFERENCE None


308


LTE-SW2108, Smart Congestion Mitigation INTRODUCTION Up to 3GPP Release 11, MMTel voice access is controlled by both Access Class Barring and Service Specific Access Control at the same time. As a result, the operator cannot control MMTel voice access separated from data access. From the 3GPP Release 12, using Smart Congestion Mitigation, The eNB can provide three bits in SIB2 in order to indicate whether MMTel voice, MMTel video and SMS UEs shall skip the Access Class Barring check. In this way, the operator can control MMTel voice access separated from data access and prioritize MMTel voice access over data access.

BENEFIT Operators can prioritize MMTel voice, MMTel video and SMS access attempts over other data packet services.

DEPENDENCY The UE should support Smart Congestion Mitigation.

LIMITATION None

FEATURE DESCRIPTION To allow UE to skip Access Class Barring for specific application such as mobile originating MMTELVoice, MMTELVideo or SMS, eNB can broadcast 3 ACB skip indicators in SIB2 in accordance with system configuration. When UE tries to establish RRC connection for specific application, UE checks relevant ACB skip indicator, and then skips ACB and consider access to the cell as not barred if ACB skip indicator for relevant application is set. Figure below depicts an example of ACB skip operation for a mobile originating MMTELVoice.


309


Using Smart Congestion Mitigation, Operator can allow access of specific applications while keep blocking packet data service at the congestion situation as depicted in the following figure.

SYSTEM OPERATION How to Activate The Smart Congestion Mitigation is to configure ACB skip indicator per service specific access control.

Key Parameters RTRV-BAR-PARA/CHG-BAR-PARA Parameter

Description

ACBARRING_SKIP_FOR_ MMTEL_VOICE

This parameter indicates to enable/disable skipping of Access Class Barring (Mo-Sig, Mo-Data) procedure when MMTEL Voice is used.

ACBARRING_SKIP_FOR_ MMTEL_VIDEO

This parameter indicates to enable/disable skipping of Access Class Barring (Mo-Sig, Mo-Data) procedure when MMTEL Video is used.

ACBARRING_SKIP_FOR_ SMS

This parameter indicates to enable/disable skipping of Access Class Barring (Mo-Sig, Mo-Data) procedure when SMS is used.



310


REFERENCE [1] TR 36.848 Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Study on smart congestion mitigation


311

Chapter 4

Mobility Control

LTE-SW1002, Idle Mobility Support INTRODUCTION To support the intra-LTE cell reselection, the eNB broadcasts the System Information Block type 3 (SIB3), SIB 4, and SIB 5. The UE monitors the EUTRAN BCCH during idle mode to retrieve these SIBs for the preparation of intra-LTE cell reselection. It measures the neighboring cells based on the criteria and performs cell reselection to intra- or inter-frequency neighboring cells.

BENEFIT You can provide idle mobility to the subscribers within E-UTRAN. LTE users in idle state can move within E-UTRAN.


FEATURE DESCRIPTION The feature provides the following functions:

PLMN Selection Cell Selection Cell Reselection Intra-Frequency Cell Reselection Combined EPS and IMSI Attach Combined EPS and IMSI Detach PLMN Selection When an LTE UE is switched on, it starts to search the Public Land Mobile Network (PLMN). The PLMN can be selected either automatically or manually, depending on the device configuration. On request from the NAS layer of the UE, if required, PLMN is already associated with LTE. The UE scans the LTE carriers based on the stored information. It searches for the strongest PLMN cell and tunes to the Physical Downlink Shared Channel (PDSCH) to read SIB1(s), where PLMN information is delivered. The PLMN reported to NAS has its measured RSRP value. Once the PLMN, high or eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 4 Mobility Control

lower quality, is selected, the UE access stratum is instructed to measure the reference signal. The UE reads the PDSCH for SIB1 again to initiate the cell selection using the S-criteria, based on Q_RX_LEV_MIN. At this stage, if the Scriteria are not met, the UE goes into the limited service, for emergency calls or finds an equivalent PLMN. Figure below illustrates the idle mode state procedure.

Selected PLMN available/unavailable: The UE scans all RF channels in the EUTRAN band according to UE capabilities to search available PLMNs.

Not camped: No suitable cell is found. Camped normally: The UE obtains normal service and performs the following tasks: oSelects and monitors the PCH of the cell. oPerforms system information monitoring. oPerforms necessary measurements for the cell reselection evaluation procedure. oExecutes the cell reselection evaluation procedure.

Camped on any cell: The UE obtains limited service and periodically searches for a suitable cell in the selected PLMN.

Cell selection: The UE selects a suitable cell and the radio access mode based on idle mode measurements and cell selection criteria.

Cell reselection: If after cell reselection evaluation process, a better cell is found, the cell reselection is performed. If there is no suitable cell, the UE enters to the next any cell selection state.

Any cell selection: UE searches an acceptable cell of any PLMN to camp on. Table below lists the parameters for PLMN selection. Parameter Name

Description

Q_RX_LEV_MIN

Minimum required RX level in the cell (dBm) (SIB1)

PLMN

MCC and MNC (SIB1)


313


Cell Selection Initial Cell Selection Figure below illustrates the initial cell selection procedures.

The UE scans all RF channels in the E-UTRAN bands based on the UE capability to find acceptable cells, which are not barred and measured RSRP is greater than or equal to -110 dBm. To read the PLMN identity and to decide the availability of the cell, the UE detects Primary/Secondary Synchronization Signals (PSS/SSS) and decodes the Cell Reference Signal (CRS) and reads at least MIB and SIB1. The PCID should not be overlapped between adjacent cells for successful detecting and decoding of the signals. The PLMN reading is reported to the NAS layer, and the search for PLMNs can be stopped on request of the NAS. Once the UE has selected the PLMN, the cell selection procedure is performed to select a suitable cell of the PLMN to camp on. If the UE has stored information of carrier frequencies and also information on cell parameters from previously received measurement, it can use this information to speed up the selection procedure. The suitable cell should meet the following conditions:

The cell is not barred. The cell is part of the selected PLMN, the registered PLMN, or the PLMN of the equivalent PLMN list.

The cell is part of at least one TA that is not port of the list of forbidden tracking areas for roaming.

The cell selection criterion S satisfies the Srxlev > 0 AND Squal > 0. Priorities between different frequencies or RATs provided to the UE by system information or dedicated signaling are not used in the cell selection procedure. Cell Barring LTE E-UTRAN cells broadcast cell selection information through SIB1 and SIB2 (AC-Barring). SIB1 has two fields for cell status indication; cellBarred and cellReservedForOperatorUse. The cellBarred is common for all PLMNs and the cellReservedForOperatorUse is specific per PLMN.


314


When cell status is indicated as 'not barred' and 'not reserved' for operator use, all UEs shall treat this cell as candidate during the cell selection and cell reselection procedures. When cell status is indicated as not barred and reserved for operator use for any PLMN:

UEs assigned to Access Class 11 or 15 operating in their HPLMN/EHPLMN treat this cell as a candidate during the cell selection and reselection procedures, if the field cellReservedForOperatorUse for the PLMN set to reserved.

UEs assigned to an access class in the range of 0 to 9 and 12 to 14 consider as if the cell status is barred in case the cell is reserved for operator use for the registered PLMN or the selected PLMN. When the cell status barred is indicated or to be treated as if the cell status is barred, the UE is not permitted to select/reselect this cell, not even for emergency calls. Cell Selection Criteria The cell selection is performed on the detected cell with RX signal and decoded MIB and SIBs. Cell selection criteria: Srxlev > 0 AND Squal > 0 Where, Srxlev = Qrxlevmeas - (Q_RX_LEV_MIN + Q_RXLEV_MIN_OFFSET) Pcompensation, Squal = Qqualmeas - (Q_QUAL_MIN + Q_QUAL_MIN_OFFSET) Table below lists the cell selection criteria. Parameter Name

Description

Srxlev

Cell selection RX level value (dB)

Squal

Cell selection quality value (dB)

Qrxlevmeas

Measured cell RX level value (RSRP)

Qqualmeas

Measured cell quality value (RSRQ)

Q_RX_LEV_MIN


Q_QUAL_MIN

Minimum required quality level in the cell (dB) (SIB1)

Q_RXLEV_MIN_OFFSET

Offset to the signalled Q_RX_LEV_MIN taken into account in the Srxlev evaluation as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN (SIB1)

Q_QUAL_MIN_OFFSET

Offset to the signalled Q_QUAL_MIN taken into account in the S qual evaluation as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN (SIB1)

Pcompensation

max(PEMAX - PPowerClass, 0) (dB)

P_MAX

Maximum TX power level an UE may use when transmitting on the uplink in the cell (dBm) defined as P_MAX in [TS 36.101] (SIB1)

PPowerClass

Maximum RF output power of the UE (dBm) according to the UE power class as defined in [TS 36.101]

Since Q_QUAL_MIN and Q_QUAL_MIN_OFFSET are not provided in network, devices test Srxlev only. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

315


If q-QualMinWB (in SIB1/SIB3/SIB5) is present, the UE, when performing RSRQ measurement, uses a wider bandwidth.

Cell Reselection Figure below illustrates the initial cell reselection procedures.

When the cell reselection condition is met, the UE in idle mode attempts to detect, synchronize, and read the system information of candidate frequencies. The UE only performs the cell reselection evaluation for E-UTRAN frequencies and interRAT frequencies that are given in the system information and for which the UE has a priority provided. The cell reselection procedures are triggered when one of the following conditions is met:

1 The serving cell does not fulfill Srxlev > S_INTRA_SEARCH_P and Squal > S_INTRA_SEARCH_Q. In this case, the UE performs intra-frequency cell reselection procedures.

2 The UE has E-UTRA frequencies or UTRA frequencies with a reselection priority higher than the reselection priority of the current E-UTRA frequency. In this case, the UE performs inter-RAT cell reselection procedures. The UE searches every layer of higher priority at least every Thigher_priority_search = (60 * Nlayers) seconds. Where Nlayers is the total number of configured higher priority E-UTRA, UTRA carrier frequencies.

3 The service cell does not fulfil Srxlev > S_NON_INTRA_SEARCH_P and Squal > S_NON_INTRA_SEARCH_Q. In this case, the UE performs inter-RAT cell reselection procedures for an E-UTRA inter-frequency, an UTRA frequency with an equal, or lower reselection priority than the reselection priority of the current E-UTRA frequency. As RSRQ related parameters are not provided in the network, devices test Srxlev only. The device uses the S_INTRA_SEARCH and S_NON_INTRA_SEARCH instead of the S_INTRA_SEARCH_P and S_NON_INTRA_SEARCH_P, respectively. Table below lists the parameters that trigger cell reselection procedures.


316

Chapter 4 Mobility Control Parameter Name

Description

Srxlev

This specifies the cell selection RX level value (in dB) measured by UE

Squal

This specifies the cell selection quality value (in dB) measured by UE

S_INTRA_SEARCH

This specifies the Srxlev threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-8 device (SIB3).

S_INTRA_SEARCH_P

This specifies the Srxlev threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-9 device (SIB3).

S_INTRA_SEARCH_Q

This specifies the Squal threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-9 device (SIB3).

S_NON_INTRA_SEARCH

This specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-8 device (SIB3).

S_NON_INTRA_SEARCH_P

This specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-9 device (SIB3).

S_NON_INTRA_SEARCH_Q

This specifies the Squal threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-9 device (SIB3).

Q_RX_LEV_MIN

This specifies the minimum required Rx level in the cell in dBm This parameter is used by Rel-9 device (SIB3).

Q_QUAL_MIN_REL9

This specifies the minimum required quality level in the cell in dB. This parameter is used by Rel-9 device (SIB3).

Thresholds and Priority Design The cell reselection triggering thresholds and priority are configured so that the UEs can select LTE network as a primary network in the presence of an acceptable LTE signal. In network, RSRP is used as a measurement triggering criteria because RSRQ can vary even in the center of the serving cell from -3 dB to -10 dB depending on traffic load from the serving cell. The S_INTRA_SEARCH should be greater than S_NON_INTRA_SEARCH so that LTE capable UEs can select LTE frequency as long as they move within the LTE coverage. Figure below illustrates the thresholds for cell reselection:


317


UE triggers the measurement of intra-frequency when the RSRP signal strength from LTE serving cell decreases below the threshold calculated as follows:

RSRP Strength from Serving Cell =< S_INTRA_SEARCH + Q_RX_LEV_MIN + Q_RXLEV_MIN_OFFSET + Pcompensation Where, Pcompensation is max (PEMAX -PPowerClass, 0) (dB). PEMAX is defined as PMAX in 3GPP TS36.101, and PPowerClass is 23 dBm as per 3GPP TS36.101. (118 dBm).Therefore, Pcompensation is usually assumed to be 0. UE triggers the measurement of UTRA frequency when the RSRP signal strength from LTE serving cell decreases below the threshold calculated as follows:

RSRP Strength from Serving Cell =< S_NON_INTRA_SEARCH + Q_RX_LEV_MIN + Q_RXLEV_MIN_OFFSET + Pcompensation UE starts the measurements of LTE frequency when the measured RSRP is less than -64 dBm [Q_RX_LEV_MIN = -63 (-126 dBm), Q_RXLEV_MIN_OFFSET = 0, S_INTRA_SEARCH = 31 (62 dB), Pcompensation = 0]. It starts the measurements of UTRA frequency when the measured RSRP is less than -112 dBm [Q_RX_LEV_MIN = -63 (-126 dBm), Q_RXLEV_MIN_OFFSET = 0, S_NON_INTRA_SEARCH = 7 (14 dB), Pcompensation = 0). For UEs, to select primarily LTE frequency when they end a CSFB call or when they come back into LTE coverage, LTE frequency priority must be greater than UTRA frequency. The priority of each frequency is broadcasted in SIB3 (E-UTRA frequency).

Intra-Frequency Cell Reselection The intra-frequency cell reselection is performed when the signal strength from LTE serving cell is less than the threshold as described above. The cell reselection is performed based on the ranking of the current and the neighboring cells. Cell reselection criteria:

Rs = Qmeas,s + Q_HYST Rn = Qmeas,n - Q_OFFSET_FREQ Table below lists the parameters of the equation mentioned above. Parameter Name

Description

Rs

Rs is for the serving cell.

Rn

Rn is for the neighbour cell.

Qmeas

RSRP measurement quantity used in cell reselections.

Q_HYST

This parameter (in dB) is to reduce ping-pong effects between serving and neighbor cells (SIB3).

Q_OFFSET_FREQ

For intra-frequency: Equals to Qoffsets,n, if Qoffsets,n is valid, otherwise this equals to zero.

T_RESELECTION

This specifies the reselection timer value for EUTRAN (SIB3).


318


The UE performs ranking of all cells that fulfil the cell selection criterion S. The cells are ranked according to the R criteria specified above, deriving Qmeas,n and Qmeas,s. The R value is calculated by the average of RSRP results. If a cell is ranked as the best cell, the UE performs cell reselection to the cell. The UE reselects the new cell, only if the following conditions are met:

The new cell is better ranked than the serving cell during a time interval T_RESELECTION.

More than 1 second has elapsed since the UE camped on the current serving cell. Initial Attach When UE camps on a suitable cell, if the new cell does not belong to at least tracking areas to which the UE is registered previously, the UE registers to the network by sending a TAU message. Figure below illustrates the initial attach procedures.


319


1 to 4) and step 2 to 4 completes a RRC connection establishing a SRB. The attach procedure starts with the RRC connection establishment procedure. The Attach Request message included in RRCConnectionSetupComplete is transparently delivered to MME in INITIAL UE MESSAGE. 5 to 9) The eNB sends the INITIAL UE MESSSAGE to MME, then MME responds with INITIAL CONTEXT SETUP REQUEST after selecting a S-GW. 10 to 12) The eNB acquires UECapabilityInformation and reports it to MME.


320


13 to 14) The eNB sends the integrity-protected AS Security Mode Command message to the UE. Then, the UE starts control plane signalling integrity. 15 to 16) The eNB sends the RRCConnectionReconfiguration message to a data radio bearer. After it receives the CONTEXT SETUP REQUEST message from MME, the eNB creates a default radio bearer by sending the RRCConnectionReconfiguration message to UE. When the UE receives the RRCConnectionReconfiguration message, it can transmit packets in uplink and the eNB can deliver the packets toward S-GW. 17) The eNB sends the Initial Context Setup Response message to MME and completes the establishment of S1 bearer. 18 to 19) The UE sends the ULInformationTransfer message to eNB, which includes Attach Complete message. This message is transparently delivered to MME in UPLINK NAS TRANSPORT message. 20 to 21) The MME sends the Modify Bearer Request message to S-GW, to provide the downlink tunnel information of eNB. After S-GW receives the Modify Bearer Request message, it can transmit packets in downlink. If both DRB and SRB do not carry any packets in downlink and uplink for a certain time period, the eNB releases the RRC connection and S1 bearer. You can configure INTERNAL_SIGNALING_INACTIVITY for a signalling bearer and INTERNAL_USER_INACTIVITY for a data bearer at eNB level. When both inactivity timers expire, the eNB sends the UE CONTEXT RELEASE message to MME and releases the S1 connection for the UE. The message indicates the cause value User Inactivity. Figure below illustrates the connection release procedure by the inactivity timer triggered.


321


Combined EPS and IMSI Attach When supporting the combined EPS/IMSI attach request, the MME selects the IWF (MSC/VLR) based on the TA and LA mapping and sends the location update request with new LAI, IMSI and the MME name to IWF. On receiving the request, the respective VLR creates an association for SGs interworking with the MME. In response, VLR provides VLR TMSI to MME. Figure below illustrates the combined EPS/IMSI attach call flow.

The combined EPS/IMSI attach procedures are:


322


1 to 5) The UE sends an Attach Request to MME with Attach Type as Combined EPS/IMSI, UE capability as CSFB and data APN name. The APN name depends on the subscriber type. The UE can include any of the Internet APN. 6) The MME sends the authentication information request message to HSS. After receiving the Authentication Information Answer from HSS, MME and UE are authenticated each other with set of authentication messages between UE and MME. After the successful authentication, the MME updates the subscriber location in the HSS and gets the subscriber profile from HSS. 7 to 8) The MME sends the Create Session Request message to S-GW for establishing the default bearer for the UE. The S-GW forwards the session request message to P-GW. The P-GW replies with the Create Session Response to MME. 9 to 10) Since the UE has requested for combined EPS/IMSI attach, after the default bearer establishment, MME updates the UE location in 3G network by sending the location update message with new LAI, IMSI and the MME name to IWF (MSC/VLR). After accepting the attach request by the network, default bearer is established. IWF updates the UE CS location in HLR. 11 to 14) The eNB acquires UECapabilityInformation and reports it to MME. 15 to 16) The eNB sends the integrity-protected AS Security Mode Command message to the UE. Then, the UE starts control plane signalling integrity. 17 to 18) The eNB sends the RRCConnectionReconfiguration message to a data radio bearer. After it receives the CONTEXT SETUP REQUEST message from MME, the eNB creates a default radio bearer by sending the RRCConnectionReconfiguration message to UE. When the UE receives the RRCConnectionReconfiguration message, it can transmit packets in uplink and the eNB can deliver the packets toward S-GW. 19) The eNB sends the Initial Context Setup Response message to MME and completes the establishment of S1 bearer. 20 to 21) The UE sends the ULInformationTransfer message to eNB, which includes Attach Complete message. This message is transparently delivered to MME in UPLINK NAS TRANSPORT message. 22 to 23) The MME sends the Modify Bearer Request message to S-GW, to provide the downlink tunnel information of eNB. After the S-GW receives the Modify Bearer Request message, it can transmit packets in downlink.

Combined EPS and IMSI Detach To detach the combined EPS/IMSI attached UE, the UE is required to be detached from both EPS and CS domains. Figure below illustrates the combined EPS/IMSI detach call flow.


323


The combined EPS/IMSI detach procedures are: 1 to 2) The UE sends Detach Request to MME. 3) The MME sends Delete Session Request message to S-GW for deactivating the default bearer for the UE. S-GW forwards the Delete Session Request message to P-GW. 4) The IMSI Detach Indication message from MME to IWF (MSC/VLR) so as to remove the SGs association with UE IMSI. 5) The P-GW replies with the Delete Session Response to MME. 6 to 8) The MME sends Detach Accept to UE and releases the S1-MME signalling connection.

Related SIB Messages SIB2 contains radio resource configuration information that is common for all UEs. Table below lists the SIB2 message. ac-BarringInfo

ac-BarringForEmergency ac-BarringForMO-Signalling (TAU, Attach/Detach message) ac-BarringforMO-Data (Service Request and Extended Service Request messages)

freqInfo

ul-CarrierFreq ul-Bandwidth additionalSpectrumEmission

radioResourceConfigCommo nSIB

rach-config, bcch-config, pcch-config, prach-config, pdsch-config, puschconfig, and pucch-config UL-CyclicPrefixLength uplinkPowerControlCommon


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Chapter 4 Mobility Control ue-TimersAndConstants timeAlignmentTimerCommon (to control how long the UE is considered uplink time aligned) mbsfn-SubframeConfigLit

SIB3 contains cell re-selection information common for intra-frequency, interfrequency and/or inter-RAT cell re-selection. Table below lists the SIB3 message. cellReselectionInfoCommon

q-Hyst speedStateReselectionPars (Q-hysteresis scaling factor depending on UE speed)

cellReselectionServingFreqInf o

s-NonIntraSearch threshServingLow cellReselectionPriority

intraFreqCellReselectionInfo

q-RxLevMin P-max (maximum uplink tx power of UE for the intra-frequency neighbouring E-UTRA cells) s-IntraSearch allowedMeasBandwidth neighCellConfig (MBSFN and TDD related information) t-ReselectionEUTRA (cell reselection timer, it can be set per E-UTRAN frequency) t-ReselectionEUTRA-SF (speed dependent scale factor)

SIB4 contains neighbouring cell related information relevant only for the intrafrequency cell re-selection. SIB4 includes cells with specific re-selection parameters and blacklisted cells. Table below lists the SIB4 message. intraFreqNeighbCellList (List of intra-frequency neighbouring cells with specific cell re-selection parameters, up to 16)

physCellId q-OffsetCell (Qoffsets,n, the offset between the two cells)

intraFreqBlackCellList (List of blacklisted intra-frequency neighbouring cells, up to 16)

Table below lists the SIB5 message. SIB5 is for information for inter-frequency cell re-selection. InterFreqCarrierFreqInfo (list of frequency information up to 8)

dl-CarrierFreq q-RxLevMin p-Max t-ReselectionEUTRA t-ReselectionEUTRA-SF threshX-High (cell reselection to a cell on a higher priority E-UTRAN frequency or inter-RAT frequency than the serving frequency if a cell of a higher priority RAT/frequency fulfils Srxlev > ThreshX, HighP during a time interval TreselectionRAT). threshX-Low (cell reselection to a cell on a lower priority E-UTRAN frequency or inter-RAT frequency than the serving frequency if the serving cell fulfils Srxlev < ThreshServing, LowP and a cell of a lower priority RAT/ frequency fulfils Srxlev > ThreshX, LowP during a time interval TreselectionRAT). allowedMeasBandwidth


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Chapter 4 Mobility Control presenceAntennaPort1 (to indicate whether all the neighbouring cells use antenna port 1) cellReselectionPriority neighCellConfig (MBSFN and TDD related information). q-OffsetFreq (Qoffsetfrequency, frequency specific offset for equal priority EUTRAN frequencies). interFreqNeighCellList (up to 16) physCellId q-OffsetCell (Qoffsets,n, the offset between the two cells). interFreqBlackCellList (up to 16)

SYSTEM OPERATION How to Activate The Idle Mobility Support is a collective feature with which the UE in Idle State (Mode) selects a network or a carrier. However, the following key parameters control the selection criteria of the cell which the UE selects. The settings of Command and Parameter can control the system information message of EUTRAN.

Key Parameters RTRV-EUTRA-FA/CHG-EUTRA-FA Parameter

Description

PRIORITY

This is a parameter specifying the priority of EUTRA-FA during idle reselection or mobility control information. '7' is the highest priority. Be careful not to set the same priority when configuring multiple EUTRA-FAs.

Q_RX_LEV_MIN

This parameter is minimum RX level required in a cell that is operating as EUTRA-FA and its unit is dBm.

T_RESELECTION

This parameter is the interval (timer) of reselection execution.

T_RESELECTION_SF_MEDI UM

This parameter is the medium timer value of the reselection scaling factor.

T_RESELECTION_SF_HIGH

This parameter is the high timer value of the reselection scaling factor.

S_INTRA_SEARCH

This parameter is the threshold value for intra-frequency measurement.

S_NON_INTRA_SEARCH

This parameter is the threshold value for the inter-RAT and inter-frequency measurement.

THRESH_SERVING_LOW

This parameter is the low threshold for serving frequency upon reselection evaluation.

THRESH_X_HIGH

This parameter is the threshold value used by the UE when reselecting the frequency with priority higher than the currently camped frequency.

THRESH_X_LOW

This parameter is the threshold value used when reselecting the low-priority frequency from the high-priority frequency.

Q-OFFSER-FREQ

This parameter is the frequency offset applied to the q-OffsetFreq of a SIB5 message.

S_INTRA_SEARCH_P

This parameter is the threshold-P value for the intra-frequency measurement of Rel-9.

S_INTRA_SEARCH_Q

This parameter is the threshold-Q value for the intra-frequency measurement of Rel-9.


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Chapter 4 Mobility Control Parameter

Description


This parameter is the threshold-P value for the inter-frequency measurement and Inter-RAT.


This parameter is the threshold-Q value for the inter-frequency measurement and Inter-RAT.

Q_QUAL_MIN_REL9

This parameter is the qQualMin value for Rel-9.

THRESH_SERVING_LOW_Q _REL9

This parameter is the threshServingLowQ value for Rel-9.

THRESH_XHIGH_Q_REL9

This parameter is the threshold value used by the UE when reselecting the frequency with priority higher than the currently camped frequency in the Rel9.

THRESH_XLOW_QREL9

This parameter is the threshold value used when reselecting the low-priority frequency from the high-priority frequency in the Rel-9.

RTRV-CELL-RSEL/CHG-CELL-RSEL Parameter

Description

Q_HYST


Q_HYST_SFMEDIUM

This parameter is the value added when the UE speed is medium among Qhyst values that are added to the current serving cell in the cell reselection criteria. To apply the change of this parameter, the SPEED_STATE_RESEL_PARAMS_USAG E should be changed to use in the CHGMOBIL-STA beforehand.

Q_HYST_SFHIGH

This parameter is the value added when the UE speed is high among Qhyst values that are added to the current serving cell in the cell reselection criteria. To apply the change of this parameter, the SPEED_STATE_RESEL_PARAMS_USAG E should be changed to use in the CHGMOBIL-STA beforehand.

Counters and KPIs There are no related counters and KPIs.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification [3] 3GPP TS36.304 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode


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LTE-SW1004, S1 Handover INTRODUCTION This is a mobility control feature between two adjacent eNBs using the S1 interface with the MME (inter-eNB handover via S1 interface). The S1 handover is used when there is no available direct interface with the target eNB, or the target eNB belongs to another MME group.

BENEFIT You can provide connected mobility to subscribers between cells in different eNBs.

Users in a connected state can move within E-UTRAN, with change of serving cell.

DEPENDENCY AND LIMITATION With full configuration, Hyper Frame Number (HFN) is reset for all bearers and lossless handover is not supported.

FEATURE DESCRIPTION Figure below illustrates the S1 handover procedure in E-UTRAN (S1 handover with MME and S-GW relocation case).


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1) The UE sends MEASUREMENT REPORT including E-UTRAN measurements to the source eNB. 2) The source eNB determines whether to perform S1-based handover into the target eNB. This decision can be initiated if there is no X2 connection to the target eNB or the inter-eNB handover of the target eNB is configured to execute the S1 handover. Handover decision in case of PCI duplication: On reception of MR message, the eNB checks whether PCI from MR exists in neighbor NRT or not. If there are several NRs with same PCI (this case is called PCI duplication), then eNB requests UE for measurement with the purpose set to reportCGI. After obtaining the measurement message including ECGI, the eNB triggers the Handover Preparation using NR of the reported ECGI. 3) The source eNB sends HANDOVER REQUIRED to the source MME. The source eNB provides information about which bearer is used for data forwarding and whether direct forwarding is possible from the source eNB to the target eNB. 4 to 6) The MME transmits the HANDOVER REQUEST message to the target eNB. This message creates the UE context which has bearer related information and security context in the target eNB. 7) The target eNB transmits the HANDOVER REQUEST ACKNOWLEDGE message to the MME. 8 to 10) If the indirect forwarding is used, the MME transmits the Create Indirect Data Forwarding Tunnel Request message to the S-GW. The S-GW replies to the MME with the Create Indirect Data Forwarding Tunnel Response message. 11) The source eNB receives the HANDOVER COMMAND from the source MME. 12) The source eNB creates the RRCConnectionReconfiguration message using the Target to Source Transparent Container IE included in the HANDOVER COMMAND message, and then transmits it to the UE. To transmit the PDCP status and the HFN status of the E-RABs of which the PDCP status must be preserved, the source eNB transmits the eNB/MME STATUS TRANSFER message to the target eNB via the MME. The source eNB must start forwarding downlink data to the target eNB through the bearer which is planned to be used for data forwarding. This can be direct or indirect forwarding. The UE performs synchronization to the target eNB and connects to the target cell through RACH. The target eNB replies with UL allocation and timing advance. 13) After successful synchronization with the target cell, the UE notifies the target cell that the handover procedure is complete using the RRCConnectionReconfigurationComplete message. The downlink packet forwarded from the source eNB can be transmitted to the UE. The uplink packet can be transmitted to the S-GW from the UE through the target eNB 14 to 16) The target eNB sends the HANDOVER NOTIFY message to MME to inform that the UE has changed cell.


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17 to 18) The MME transmits the Modify Bearer Request message to the S-GW per each PDN connection. The downlink packet from the S-GW is immediately transmitted to the target eNB. 19) The S-GW transmits the Modify Bearer Response message to the MME. To support packet re-arrangement in the target eNB, the S-GW transmits at least one end marker packets to the previous path as soon as the path is changed. 20) If any of the conditions listed in Section 5.3.3.0 of TS 23.401 (6) is met, the UE starts the Tracking Area Update procedure. 21 to 24) The source MME releases the UE resources that are used in the source eNB and the resources for data forwarding.

Full Configuration Full configuration option is used to support EUTRA handover to an eNB of an earlier release. The target uses a full configuration and the previous configuration is discarded by the UE. This can lead to a change in RLC mode for a bearer and the operation for RLC AM is the same as that for RLC UM. HFN is reset for all bearers. Since the source eNB is not aware that the target eNB is using full configuration, there is no difference in the source eNB behaviour. The target eNB does not resend data that was attempted delivery to the UE to prevent data duplication. Source the eNB includes ue-ConfigRelease IE in HandoverPreparationInformation message, the ue-ConfigRelease IE indicates the RRC protocol release used for the UE specific dedicated configuration. If the target eNB does not support the release of RRC protocol, which the source eNB used to configure the UE, the target eNB unable to comprehend the UE configuration provided by the source eNB. In this case, the target eNB should use the full configuration option to reconfigure the UE for handover and re-establishment. Full configuration option includes an initialization of the radio configuration, which makes the procedure independent of the configuration used in the source cell with the exception that the security algorithms are continued for the RRC re-establishment. For reconfigurations involving the full configuration option, the PDCP entities are newly established (SN and HFN do not continue) for all DRBs irrespective of the RLC mode. The UE deletes the current configuration and applies new configuration based on the configuration provided by the target eNB. The security configuration is retained and the security algorithm is retained for re-establishment. SRBs are reconfigured, DRBs are released, and re-setup using new configuration.

SYSTEM OPERATION How to Activate Select 1 event to use for activating the S1 handover. ACTIVE_STATE of CHG-EUTRA-A3CNF with PURPOSE A3PurposeIntraLteHandover set to active or ACTIVE_STATE of CHGEUTRA-A5CNF with PURPOSE A5PurposeIntraLteHandover set to active eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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A3 event is preferred. Set NO_HO of CHG-NBR-ENB to false. It is controlled by NBR eNB base. Key Parameters CHG-EUTRA-A3CNF/RTRV-EUTRA-A3CNF Parameter

Description

PURPOSE

The purpose for using Event A5. Not in current use. The definition is made for later use. ci_A5PurposeIntraLteHandover: Intra-LTE handover. ci_A5PurposeSpare_1: Reserved. ci_A5PurposeSpare_2: Reserved.

ACTIVE_STATE

Whether to use the Event A5. Inactive: Event A5 is not used. Active: Event A5 is used.

A5_THRESHOLD1_RSRP

RSRP threshold1 used for triggering the EUTRA measurement report for Event A5.

A5_THRESHOLD2_RSRP


TIME_TO_TRIGGER

timeToTrigger value for Event A5. The time-ToTrigger value is the period of time that must be met for the UE to trigger a measurement report.

TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A5 during ReportConfigEutra configuration. The triggerQuantity can be set to rsrp/rsrq/followA2Event. An UE transmits Event A5 when RSRP or RSRQ meets a specific threshold according to triggerQuantity. If the triggerQuantity is RSRP, the A5_THRESHOLD_RSRP is used. If it is RSRQ, the A5_THRESHOLD_RSRQ is used. If the triggerQuantity is followA2Event, it follows the triggerQuantity of the previously received A2 event with handover purpose. (it is noted that this configuration is only available if the A5 purpose is handover related case, that is, A5PurposeIntraLteHandover). This change is applied to the UE from next RRC signaling procedure (for example, attach or idle to active). To avoid overload, new setting is not updated to the current active UEs. rsrp: The trigger quantity of this event is set RSRP. rsrq: The trigger quantity of this event is set RSRQ. followA2Event: The trigger quantity of this event follows the trigger quantity of the previously received A2 event.

CHG-EUTRA-A5CNF/RTRV-EUTRA-A5CNF Parameter

Description

PURPOSE

The purpose for using Event A3. It is currently used for intra-LTE handover and the SON ANR function. IntraLteHandover ReportStrongestCells IntraFrequencyLb CaInterFreq

ACTIVE_STATE

Whether to use Event A3. Inactive: Event A3 is not used. Active: Event A3 is used.


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Description

A3_OFFSET

RSRP threshold used for triggering the EUTRA measurement report for Event A3.

TIME_TO_TRIGGER


TRIGGER_QUANTITY

Quantity (RSRP/RSRQ) used to calculate a triggering condition for Event A3. Either RSRP or RSRQ is assigned.

CHG-NBR-ENB/RTRV-NBR-ENB/CRTE-NBR-ENB/DLT-NBR-ENB Parameter

Description

NO_X2

Whether to make X2 connection to the neighboring eNB. False: X2 connection with the neighboring eNB is made. True: X2 connection to the neighboring eNB is not made.

NO_HO

Whether to perform handover to the neighboring eNB. False: Handover to the neighboring eNB is performed. True: Handover to the neighboring eNB is not performed.


Type Name

Type Description

S1 Out Handover

InterS1OutAtt

The number of attempts for S1 handover in SeNB.

InterS1OutPrepSucc

The number of successes for S1 handover preparation in SeNB.

InterS1OutSucc

The number of successes for S1 handover execution in SeNB.

InterS1OutPrepFail_CpCc Fail

Preparation fails due to reset notification (eNB failure or block restart) from ECMB or by ECCB block during inter S1 handover preparation.

InterS1OutPrepFail_S1ap CuFail

Preparation fails due to S1AP specification cause during inter S1 handover preparation.

InterS1OutPrepFail_S1ap LinkFail

Preparation fails due to S1 SCTP link failure during inter S1 handover preparation.

InterS1OutPrepFail_S1ap RpTo

Preparation fails due to S1AP relocprep timeout (not received) during the inter S1 handover preparation.

InterS1OutPrepFail_S1ap SigFail

Preparation fails due to receiving S1AP signaling during inter S1 handover preparation.

InterS1OutFail_CpCcTo

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the inter S1 handover execution.

InterS1OutFail_CpCcFail

A call is released due to reset notification (eNB failure or block restart) from ECMB or by ECCB block during the inter S1 handover execution.

InterS1OutFail_UpGtpFail

A call is released due to the failure in the GTP block during the inter S1 handover execution.

InterS1OutFail_UpMacFai l

A call is released due to the failure in the MAC block during the inter S1 handover execution.

InterS1OutFail_UpPdcpFa il

A call is released due to the failure in the PDCP block during the inter S1 handover execution.


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Chapter 4 Mobility Control Family Display Name

S1 In Handover

Type Name

Type Description

InterS1OutFail_UpRlcFail

A call is released due to the failure in the RLC block during the inter S1 handover execution.

InterS1OutFail_RrcSigFail

A call is released due to receiving RRC signaling during the inter S1 handover execution.

InterS1OutFail_S1apCuF ail

A call is released due to the S1AP specification cause during the inter S1 handover execution.

InterS1OutFail_S1apLink Fail

A call is released due to the S1 SCTP link failure during the inter S1 handover execution.

InterS1OutFail_S1apRoT O

A call is released due to S1AP relocoverall timeout (not received) during the inter S1 handover execution.

InterS1OutFail_S1apSigF ail

A call is released due to receiving S1AP signaling during the inter S1 handover execution.

InterS1OutCnt

S1 Handover Out collection count

InterS1OutCid

tcID of which collection is requested

InterS1InAtt

S1 handover attempt count in TeNB

InterS1InPrepSucc

S1 handover preparation success count in TeNB

InterS1InSucc

S1 handover execution success count in TeNB

InterS1InPrep_FailCpCcT o

Preparation fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the inter S1 handover preparation.

InterS1InPrep_FailCpCcF ail

Preparation fails due to reset notification (eNB failure or block restart) from ECMB or ECCB block during inter S1 handover preparation.

InterS1InPrep_FailUpGtp Fail

Preparation fails due to internal failure in the GTP block during the inter S1 handover preparation.

InterS1InPrep_FailUpMac Fail

Preparation fails due to internal failure in the MAC block during the inter S1 handover preparation.

InterS1InPrep_FailUpPdc pFail

Preparation fails due to internal failure in the PDCP block during the inter S1 handover preparation.

InterS1InPrep_FailUpRlcF ail

Preparation fails due to internal failure in the RLC block during the inter S1 handover preparation.

InterS1InPrep_FailCpBhC acFail

Preparation fails due to insufficient backhaulbased eNB resources during inter S1 handover preparation.

InterS1InPrep_FailCpCap aCacFail

Preparation fails due to insufficient capacity-based eNB resources during inter S1 handover preparation.

InterS1InPrep_FailCpQos CacFail

Preparation fails due to insufficient QoS-based eNB resources during inter S1 handover preparation.

InterS1InPrep_FailS1apC uFail

Preparation fails due to S1AP specification cause during inter S1 handover preparation.

InterS1InPrep_FailS1apLi nkFail

Preparation fails due to S1 SCTP link failure during inter S1 handover preparation.

InterS1InPrep_FailS1apSi gFail

Preparation fails due to receiving S1AP signaling during inter S1 handover preparation.

InterS1InFail_CpCcTo

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during


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Handover Time

MOBILITY (KPI)

Type Name

Type Description the inter S1 handover execution.

InterS1InFail_CpCcFail

A call is released due to reset notification (eNB failure or block restart) from ECMB or by ECCB block during the inter S1 handover execution.

InterS1InFail_UpGtpFail

A call is released due to the failure in the GTP block during the inter S1 handover execution.

InterS1InFail_UpMacFail

A call is released due to the failure in the MAC block during the inter S1 handover execution.

InterS1InFail_UpPdcpFail

A call is released due to the failure in the PDCP block during the inter S1 handover execution.

InterS1InFail_UpRlcFail

A call is released due to the failure in the RLC block during the inter S1 handover execution.

InterS1InFail_RrcHcTo

A call is released due to HO command timeout (not received) during the inter S1 handover execution.

InterS1InFail_RrcSigFail

A call is released due to receiving RRC signaling during the inter S1 handover execution.

InterS1InFail_S1apCuFail

A call is released due to the S1AP specification cause during the inter S1 handover execution.

InterS1InFail_S1apLinkFa il

A call is released due to the S1 SCTP link failure during the inter S1 handover execution.

InterS1InFail_S1apSigFail

A call is released due to receiving S1AP signaling during the inter S1 handover execution.

InterS1InFail_S1apSigTo

A call is released due to S1AP signaling timeout (not received) during the inter S1 handover execution.

IntraHOTime

Time taken from transmitting the RRCConnectionReconfiguration message to the UE until after receiving the RRCConnection ReconfigurationComplete message from the UE.

IntraHOTimeMax

Average maximum intra HO interrupt time

IntraHOTimeTot

Sum of Intra HO Interrupt time

IntraHOTimeCnt

Count of IntraHoTimeAvg collected

S1HOTime

Average S1 HO interrupt time

S1HOTimeMax

Average maximum S1 HO interrupt time

S1HOTimeTot

Sum of S1 HO interrupt time

S1HOTimeCnt

Count of S1HoTimeAvg collected

X2HOTime

Average X2 HO interrupt time

X2HOTimeMax

Average maximum X2 HO interrupt time

X2HOTimeTot

Sum of X2 HO Interrupt time

X2HOTimeCnt

Count of X2HoTimeAvg collected

HoTimeCnt

Count of HoTime collected

HoTimeCid

scID which collection is requested

EutranMobilityHOS1Out

HOIS1Out success rate of E-UTRAN mobility

sumHOS1Out_Att

Total S1 handover attempt count in SeNB

sumHOS1Out_Succ

Total S1 handover execution success count in SeNB


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Type Name

Type Description

sumHOS1Out_PrepSucc

Total S1 handover preparation success count in SeNB

EutranMobilityHOS1In

HOS1In success rate of E-UTRAN mobility

sumHOS1In_Att

Total S1 handover attempt count in TeNB

sumHOS1In_Succ

Total S1 handover execution success count in SeNB

sumHOS1In_PrepSucc

Total S1 handover preparation success count in TeNB



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LTE-SW1005, X2 Handover INTRODUCTION X2 handover is a handover between two adjacent eNBs using the X2 interface (inter eNB handover via X2 interface). X2 based handover is used when there is an available direct interface with the target eNB and the target eNB belongs to the same MME group.

BENEFIT The operator can provide connected mobility to its subscribers between cells in different eNBs.

Users in a connected state can be moving within E-UTRAN, with change of serving cell.

DEPENDENCY Prerequisite Features LTE-SW0521 (X2 Interface Management)

Others With Full Configuration, HFN is reset for all bearers and lossless HO is not supported.

LIMITATION None

SYSTEM IMPACT Interdependencies between Features This feature can be activated only when the LTE-SW0521 (X2 Interface Management) feature is enabled.

FEATURE DESCRIPTION X2 handover is a handover between two adjacent eNBs using the X2 interface (inter eNB handover via X2 interface).


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When eNB receives a measurement report including Event A3 from UE, eNB triggers intra-LTE handover to the best cell indicated in the measurement report. Because handover target cell is decided by UE‟s measurement results for neighbouring cells. X2 handover is used when there is available direct interface with the target eNB, or the target eNB belongs to the same MME group. eNB can transit from X2 handover to S1 handover with direct forwarding, when X2 setup fail (cause: Invalid MME Group ID). Figure below depicts the X2 handover procedure in E-UTRAN.

1) UE sends MEASUREMENT REPORT including E-UTRAN measurements to the source eNB. 2) The source eNB determines whether to accept the UE based on the MeasurementReport message and radio resource management information. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Handover decision in case of PCI duplication: On reception of MR message, eNB checks whether PCI from MR exists in Neighbor NRT or not. If there are several NRs with same PCI (this case is called PCI duplication), then eNB asks UE for measurement with the purpose set to reportCGI. After obtaining MR message including ECGI, eNB triggers Handover Preparation using NR of the reported ECGI. 3) The source eNB transmits the HANDOVER REQUEST message and the information necessary for handover to the target eNB. 4) The target eNB performs admission control for the incoming handover request. If accepted, the target eNB prepares the handover and creates the RRCConnectionReconfiguration message including the mobilityControlInfo IE that tells the source eNB to perform the handover. The target eNB includes the RRCConnectionReconfiguration message in the HANDOVER REQUEST ACKNOWLEDGE message and transmits it to the source eNB. Bearer Setup list includes a list of tunnel information for receiving forwarded data if necessary. 5) The RRC CONNECTION RECONFIGURATION for handover is constructed by the serving eNB and is sent to the UE. To send the uplink PDCP SN receiver status and the downlink PDCP SN transmitter status of the E-RABs of which the PDCP status must be preserved, the source eNB sends the SN STATUS TRANSFER message to the target eNB. After receiving the RRCConnectionReconfiguration message that includes the mobilityControlInfo IE, the UE performs synchronization with the target eNB and connects to the target eNB through the Random Access CHannel (RACH). The target cell replies with UL allocation and timing advance. 6) The UE performs the handover to the target cell. After the UE has successfully synchronized to the target cell, it sends a RRC CONNECTION RECONFIGURATION COMPLETE message to the target cell. 7) The target eNB sends a PATH SWITCH REQUEST message to MME to inform that the UE has changed cell. 8~10) The MME sends the Modify Bearer Request message to the S-GW. The SGW changes the downlink data path into the target eNB. The S-GW transmits at least one end marker to the source eNB through the previous path and releases the user plane resource for the source eNB. 11) The S-GW transmits the Modify Bearer Response message to the MME. 12) The MME returns the PATH SWITCH ACKNOWLEDGE message to the target eNB. 13) The target eNB sends the UE CONTEXT RELEASE message to the source eNB to notify the handover has succeeded and to make the source eNB release its resources. If the source eNB receives the UE CONTEXT RELEASE message, it releases the radio resources and the control plane resources related to the UE context.


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14) If Serving GW is relocated, the MME releases the UE‟s resources that was used in the source Serving GW.

Enhancement Full configuration option is used to support EUTRA handover to an eNB of an earlier release. The target uses a full configuration and the previous configuration is discarded by the UE. This can lead to a change in RLC mode for a bearer and the operation for RLC AM is the same as that for RLC UM. HFN is reset for all bearers. Since the source eNB may not be aware that target eNB is using full configuration, there is no difference in the source eNB behaviour. The target eNB does not resend data that was attempted delivery to the UE to prevent data duplication. Source eNB includes ue-ConfigRelease IE in HandoverPreparationInformation message, ue-ConfigRelease IE indicates the RRC protocol release used for the UE specific dedicated configuration. If the target eNB does not support the release of RRC protocol which the source eNB used to configure the UE, the target eNB may be unable to comprehend the UE configuration provided by the source eNB. In this case, the target eNB should use the full configuration option to reconfigure the UE for Handover and Re-establishment. Full configuration option includes an initialization of the radio configuration, which makes the procedure independent of the configuration used in the source cell with the exception that the security algorithms are continued for the RRC re-establishment. For reconfigurations involving the full configuration option, the PDCP entities are newly established (SN and HFN do not continue) for all DRBs irrespective of the RLC mode. UE deletes current configuration and applies new configuration based on the configuration provided by the target eNB. Security configuration is retained and security algorithm is retained for re-establishment. SRBs are reconfigured. DRBs are released and re-setup using new configuration. Figure below depicts general message flow:


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1 Source eNB sends Handover Request message including ue-ConfigRelease IE. 2 Target eNB sets FullConfig IE to true if ue-ConfigRelease IE is higher than RRC Protocol release of target eNB.

3 Target eNB sends Handover Request Acknowledge message including FullConfig IE.

4 Source eNB forwards RRC Connection Reconfiguration message to UE. 5 Source eNB transmits RRC Connection Reconfiguration Complete message to Target eNB.

6 UE deletes current configuration of source eNB and applies new configuration provided by target eNB except security configuration.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation To activate this feature, do the following:

Run CHG-EUTRA-A3CNF and set ACTIVE_STATE corresponding to PURPOSE (A3PurposeIntraLteHandover) to active or Run CHG-EUTRA-A5CNF and set ACTIVE_STATE corresponding to PURPOSE (A5PurposeIntraLteHandover) to active.

A3 event is preferred. Run CHG-NBR-ENB and set NO_X2 to false. It is controlled by NBR eNB base. Deactivation Procedure To deactivate this feature, do the following:

Run CHG-EUTRA-A3CNF and set ACTIVE_STATE corresponding to PURPOSE (A3PurposeIntraLteHandover) to Inactive or

Run CHG-EUTRA-A5CNF and set ACTIVE_STATE corresponding to PURPOSE (A5PurposeIntraLteHandover) to Inactive.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-EUTRA-A3CNF/RTRV-EUTRA-A3CNF Parameter

Description

PURPOSE

This parameter is the purpose of using Event Event A3. IntraLteHandover: Performs handover. ReportStrongestCells: Performs the ANR operation. IntraFrequencyLb: Performs Intra Frequency Load Balancing. CaInterFreq: Performs InterFrequency Carrier Aggregation. IntraFrequencyCre: Performs IntraFrequency CRE. PeriodicMr: Performs Periodic Measurement Report for eICIC.

ACTIVE_STATE



Description

PURPOSE


ACTIVE_STATE


A3_OFFSET


TIME_TO_TRIGGER


TRIGGER_QUANTITY


Parameter Descriptions of CHG-EUTRA-A5CNF/RTRV-EUTRA-A5CNF Parameter

Description

PURPOSE

The purpose for using Event A5. Not in current use. The definition is made for later use. ci_A5PurposeIntraLteHandover: Intra-LTE handover. ci_A5PurposeSpare_1: Reserved. ci_A5PurposeSpare_2: Reserved.

ACTIVE_STATE

Whether to use the Event A5.


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Description Inactive: Event A5 is not used. Active: Event A5 is used.

A5_THRESHOLD2_RSRP


A5_THRESHOLD2_RSRQ


TIME_TO_TRIGGER


TRIGGER_QUANTITY


Parameter Descriptions of RTRV-NBR-EUTRAN/CHG-NBR-EUTRAN/CRTENBR-EUTRAN/DLT-NBR-EUTRAN Parameter

Description

CELL_NUM


RELATION_IDX

Database index of E-UTRAN neighboring cell.

STATUS

The validity of the E-UTRAN neighboring cell information. N_EQUIP: The E-UTRAN neighboring cell information is invalid. EQUIP: The E-UTRAN neighboring cell information is valid.

ENB_ID

The eNB ID of the eNB to which E-UTRAN neighboring cell to the eNB belongs. If the enbType value is macro eNB, 20 bit of the value is eNB ID. If the enbType value is home eNB, 28 bit of the value is eNB ID. It is used when creating a cell identifier.

TARGET_CELL_NUM

The local cell ID of E-UTRAN neighboring cell to the eNB. It is used when creating a cell identifier.

ENB_TYPE

The type of the eNB to which E-UTRAN neighboring cell to the eNB belongs. ci_Macro_eNB: Indicates the macro eNB. ci_Home_eNB: Indicates the home eNB.

ENB_MCC

The PLMN information (MCC) of the eNB to which E-UTRAN neighboring cell to the eNB belongs. It is a three-digit number with each digit being from 0 to 9.

ENB_MNC

The PLMN information (MNC) of the eNB to which E-UTRAN neighboring cell to the eNB belongs. It is a three-digit or two-digit number with each digit being from 0 to 9.

PHY_CELL_ID

The physical cell ID of E-UTRAN neighboring cell to the eNB.

TAC

The tracking area code of E-UTRAN neighboring cell to the eNB.

MCC0

The broadcast PLMN list information (MCC) of E-UTRAN neighboring cell to the eNB. It is a three-digit number with each digit being from 0 to 9.

MNC0

The broadcast PLMN list information (MNC) of E-UTRAN neighboring cell to the eNB. It is a three-digit or two-digit number with each digit being from 0 to 9.

MCC1


MNC1



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Description

MCC2


MNC2


MCC3


MNC3


MCC4


MNC4


MCC5


MNC5


EARFCN_UL

The uplink EARFCN (E-UTRAN Absolute Radio Frequency Channel Number) of EUTRAN neighboring cell to the eNB.

EARFCN_DL

The uplink EARFCN (E-UTRAN Absolute Radio Frequency Channel Number) of EUTRAN neighboring cell to the eNB.

BANDWIDTH_UL

The uplink bandwidth of E-UTRAN neighboring cell to the eNB.

BANDWIDTH_DL

The downlink bandwidth of E-UTRAN neighboring cell to the eNB.

IND_OFFSET

The cell individual offset to be applied to EUTRAN neighboring cell to the eNB. It is used for UE measurement in RRC Connected mode.

QOFFSET_CELL

The cell quality offset to be applied to EUTRAN neighboring cell to the eNB. It is used for UE cell re-selection in RRC Idle mode.

IS_REMOVE_ALLOWED

Whether to delete a certain neighboring cell to the eNB using the ANR (Automatic Neighbor Relation) function. True: The neighboring cell can be deleted. False: The neighboring cell cannot be deleted.

IS_HOALLOWED

Whether to perform handover to E-UTRAN neighboring cell. True: Handover is allowed. False: Handover is not allowed.

IS_COLOCATED

This parameter defines whether this neighbor cell is co-located with the serving cell or not. True: The neighboring cell is co-located. False: The neighboring cell is NOT co-located.

Counters and KPIs Table below outlines the main counters associated with this feature Display Name

Type Name

Type Description

X2 Handover Out

InterX2OutAtt

Attempt count for X2 handover from SeNB.

InterX2OutPrepSucc

Success count for X2 handover preparation from SeNB.

InterX2OutSucc

Success count for X2 handover execution from SeNB.

InterX2OutPrepFail_CP_CC_F

Preparation fails due to reset notification


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Chapter 4 Mobility Control Display Name

Type Name AIL

Type Description (eNB failure or block restart) from ECMB or by ECCB block during the inter X2 handover preparation.

InterX2OutPrepFail_S1AP_LIN K_FAIL

Preparation fails due to S1 SCTP link failure during the inter X2 handover preparation.

InterX2OutPrepFail_S1AP_SIG _FAIL

Preparation fails due to receiving S1AP signaling during the inter X2 handover preparation.

InterX2OutPrepFail_X2AP_CU _FAIL

Preparation fails due to X2AP specification cause during the inter X2 handover preparation.

InterX2OutPrepFail_X2AP_LIN K_FAIL

Preparation fails due to X2 SCTP link failure during the inter X2 handover preparation.

InterX2OutPrepFail_X2AP_RP _TO

Preparation fails due to X2AP relocprep timeout (not received) during the inter X2 handover preparation.

InterX2OutPrepFail_X2AP_SIG _FAIL

Preparation fails due to receiving X2AP signaling during the inter X2 handover preparation.

InterX2OutFail_CP_CC_TO

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the inter X2 handover execution.

InterX2OutFail_CP_CC_FAIL

A call is released due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block during the inter X2 handover execution.

InterX2OutFail_UP_GTP_FAIL

A call is released due to the failure in the GTP block during the inter X2 handover execution.

InterX2OutFail_UP_MAC_FAIL

A call is released due to the internal failure in the MAC block during the inter X2 handover execution.

InterX2OutFail_UP_PDCP_FAI L

A call is released due to the internal failure in the PDCP block during the inter X2 handover execution.

InterX2OutFail_UP_RLC_FAIL

A call is released due to the internal failure in the RLC block during the inter X2 handover execution.

InterX2OutFail_RRC_SIG_FAI L

A call is released due to receiving RRC signaling during the inter X2 handover execution.

InterX2OutFail_S1AP_CU_FAI L

A call is released due to the S1AP specification cause during the inter X2 handover execution.

InterX2OutFail_S1AP_LINK_F AIL

A call is released due to the S1 SCTP link failure during the inter X2 handover execution.

InterX2OutFail_S1AP_SIG_FAI L

A call is released due to receiving S1AP signaling during the inter X2 handover execution.

InterX2OutFail_X2AP_CU_FAI

A call is released due to the X2AP specification cause during the inter X2


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X2 Handover In

Type Name L

Type Description handover execution.

InterX2OutFail_X2AP_LINK_F AIL

A call is released due to the X2 SCTP link failure during the inter X2 handover execution.

InterX2OutFail_X2AP_RO_TO

A call is released due to X2AP RelocOverall timeout (not received) during the inter X2 handover execution.

InterX2OutFail_X2AP_SIG_FAI L

A call is released due to receiving the X2AP signaling during the inter X2 handover execution.

InterX2InAtt

The number of attempts for X2 handover in TeNB

InterX2InPrepSucc

The number of successes for X2 handover preparation in TeNB

InterX2InSucc

The number of successes for X2 handover execution in TeNB

InterX2InPrepFail_CP_CC_TO

Preparation fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the inter X2 handover preparation.

InterX2InPrepFail_CP_CC_FAI L

Preparation fails due to reset notification (eNB failure or block restart) from ECMB or by ECCB block during the inter X2 handover preparation.

InterX2InPrepFail_UP_GTP_F AIL

Preparation fails due to internal failure in the GTP block during the inter X2 handover preparation.

InterX2InPrepFail_UP_MAC_F AIL

Preparation fails due to internal failure in the MAC block during the inter X2 handover preparation.

InterX2InPrepFail_UP_PDCP_ FAIL

Preparation fails due to internal failure in the PDCP block during the inter X2 handover preparation.

InterX2InPrepFail_UP_RLC_F AIL

Preparation fails due to internal failure in the RLC block during the inter X2 handover preparation.

InterX2InPrepFail_CP_BH_CA C_FAIL

Preparation fails due to insufficient backhaulbased eNB resources during the inter X2 handover preparation.

InterX2InPrepFail_CP_CAPA_ CAC_FAIL

Preparation fails due to insufficient capacitybased eNB resources during the inter X2 handover preparation.

InterX2InPrepFail_CP_QOS_C AC_FAIL

Preparation fails due to insufficient QoSbased eNB resources during the inter X2 handover preparation.

InterX2InPrepFail_S1AP_LINK _FAIL


InterX2InPrepFail_S1AP_SIG_ FAIL


InterX2InPrepFail_X2AP_CU_ FAIL



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Type Name

Type Description

InterX2InPrepFail_X2AP_LINK _FAIL


InterX2InPrepFail_X2AP_SIG_ FAIL


InterX2InFail_CP_CC_TO


InterX2InFail_CP_CC_FAIL


InterX2InFail_UP_GTP_FAIL


InterX2InFail_UP_MAC_FAIL


InterX2InFail_UP_PDCP_FAIL


InterX2InFail_UP_RLC_FAIL


InterX2InFail_RRC_HC_TO

A call is released due to HO command timeout (not received) during the inter X2 handover execution.

InterX2InFail_RRC_SIG_FAIL


InterX2InFail_S1AP_CU_FAIL


InterX2InFail_S1AP_LINK_FAI L


InterX2InFail_S1AP_PATH_TO

A call is released due to S1AP path switch timeout (not received) during the inter X2 handover execution.

InterX2InFail_S1AP_SIG_FAIL


InterX2InFail_X2AP_CU_FAIL

A call is released due to the X2AP specification cause during the inter X2 handover execution.

InterX2InFail_X2AP_LINK_FAI L


InterX2InFail_X2AP_SIG_FAIL



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MOBILITY (KPI)

Type Name

Type Description

InterX2InFail_X2AP_SIG_TO

A call is released due to X2AP signaling timeout (not received) during the inter X2 handover execution.

EutranMobilityHOX2Out

HOX2Out success rate of E-UTRAN mobility

sumHOX2Out_Att

Total X2 handover attempt count in SeNB

sumHOX2Out_Succ

Total X2 handover execution success count in SeNB

sumHOX2Out_PrepSucc

Total X2 handover preparation success count in SeNB

EutranMobilityHOX2In

HOX2In success rate of E-UTRAN mobility

sumHOX2In_Att

Total X2 handover attempt count in TeNB

sumHOX2In_Succ

Total X2 handover execution success count in TeNB

sumHOX2In_PrepSucc

Total X2 handover preparation success count in TeNB



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LTE-SW1006, Data Forwarding INTRODUCTION During handover, source eNB forwards PDCP SDUs in sequence to target eNB. Direct data forwarding is used when a direct path between source eNB and target eNB is available. Otherwise indirect data forwarding is used, where PDCP packets are delivered to target eNB through S-GW.

BENEFIT Users can obtain session continuity during handover within E-UTRAN, with almost no interruption.

DEPENDENCY Prerequisite Features LTE-SW1004 (S1 handover), LTE-SW1005 (X2 handover)

LIMITATION None

SYSTEM IMPACT Interdependencies between Features This feature can be activated only when the LTE-SW1004 (S1 Handover) or LTESW1005 (X2 Handover) feature is enabled.

FEATURE DESCRIPTION The source eNB decides which of the EPS bearers are subject for forwarding of packets from the source eNB to the target eNB. Samsung source eNB always requests downlink forwarding to the target eNB and the bearers that have accepted by the target eNB will be forwarded. Samsung target eNB always accepts downlink forwarding if handover admission is success. If uplink forwarding, Samsung target eNB requests to the source eNB according to system configuration by operator and the bearers that have accepted by the source eNB will be forwarded. Samsung source eNB always accepts the uplink forwarding request from the target eNB. Following packets can be forwarded to the target eNB based on 3GPP standards:

Downlink packets that have not been acknowledged by the UE (RLC-AM) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Downlink packets for which transmission have not been completed (RLC-UM) Fresh data arriving over S1 (RLC-AM/UM) Uplink data received out of sequence (RLC-AM) Direct data forwarding is operated in the following two cases when there exists an X2 connection between eNBs:

Inter-eNB S1 handover Inter-eNB X2 handover Figure below depicts X2/S1 handover data forwarding.

Direct data forwarding at Inter-eNB X2 handover A handover occurs via X2 interface when the UE moves between eNBs in the same MME group. If the X2 interface exists between different eNB cells, direct data forwarding is operated (only applicable to radio bearers acting as RLC AM). When performing handover via the X2 interface, the target eNB determines whether to perform uplink data forwarding. The source eNB performs uplink data forwarding only when the target eNB admits it. During the handover, the RLC layer block of the source eNB assembles SDUs through re-establishing the RLC to deliver the AM-mode uplink PDUs that previously failed to be delivered to the PDCP layer block. In case of uplink data forwarding, the PDCP layer block configures the PDCP SN status including completion of SDU forwarding from the RLC layer block. If uplink data forwarding is not operated, the PDCP layer block configures the PDCP SN status based on uplink data received so far. Figure below depicts data forwarding at Inter-eNB X2 handover.


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1 The UE sends the MeasurementReport message according to rules, such as the system information or specifications, and the source eNB decides whether to accept the UE based on the MeasurementReport message and radio resources management information.

2 The source eNB sends the HANDOVER REQUEST message and other handover-related information to the Target eNB. It, then, operates management control according to the E-RAB QoS information received.

3 The target eNB prepares the handover and creates the RRCConnectionReconfiguration message including the mobilityControlInfo IE that allows the handover to be performed. The target eNB sends to the source eNB the HANDOVER REQUEST ACKNOWLEDGE message containing RRCConnectionReconfiguration.

4 The source eNB sends the UE the RRCConnectionReconfiguration message, containing the needed parameter values to command the handover.


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5 To send the uplink PDCP SN receiver status and the downlink PDCP SN transmitter status of the E-RABs of which the PDCP status must be preserved, the source eNB sends the SN STATUS TRANSFER message to the target eNB. (Data forwarding can be possible even if it receives UE context release message during it receives End marker or timer limits.)

6 Upon receiving the RRCConnectionReconfiguration message containing mobilityControlInfo IE, the UE synchronizes with the target eNB and connects to the target cell via the Random Access Channel (RACH). The target eNB responds with UL allocation and timing advance.

7 After having connected to the target cell successfully, the UE notifies the target cell that the handover procedure has been completed, using the RRCConnection ReconfigurationComplete message.

8 The target eNB, using the PATH SWITCH REQUEST message, notifies the MME that the UE has changed the cell.

9 The MME sends the Modify Bearer Request message to the S-GW, which changes the downlink data path toward the target and sends one or more end markers to the source eNB through the previous path, releasing user plane resources for the source eNB. The source eNB sends one or more 'end markers' to the target eNB after all data from the source eNB gets forwarded to the target eNB.

10 The S-GW sends the Modify Bearer Response message to the MME. 11 The MME acknowledges the PATH SWITCH REQUEST message by issuing the PATH SWITCH REQUEST ACKNOWLEDGE message.

12 The target eNB sends the UE CONTEXT RELEASE message to the source eNB to notify the handover has succeeded and to make the source eNB release its resources. If the source eNB receives the UE CONTEXT RELEASE message, it releases the radio resources and the control plane resources related to the UE context.(Data forwarding can be possible until source eNB send End Marker)

Data forwarding at Inter-eNB S1 handover A handover is performed via the S1 interface when the UE moves between cells of different eNBs. Generally, a handover is carried out via the X2 interface for two eNBs in the same MME, and via the S1 interface for the eNBs in different MMEs. However, if the two eNBs in the same MME do not have the X2 interface, the handover is performed via the S1 interface. If the handover is done through the S1 interface and the X2 interface exists between the two eNBs, direct data forwarding is operated via X2-U. If there is no X2 interface, indirect data forwarding is performed via S1-U. Figure below depicts data forwarding at Inter-eNB S1 handover.


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1 The source eNB makes a decision on an S1-based handover to the target eNB. The decision can take place when there is no X2 connection to the target eNB, or an inter-eNB handover of the target eNB is set to occur through S1.

2 The source eNB sends the HANDOVER REQUIRED message to the MME, giving information on which bearer is used for data forwarding and whether direct forwarding from the source eNB to the target eNB is possible.

3 The MME sends to the target eNB the HANDOVER REQUEST message, which creates, in the target eNB, bearer information and the UE context including security context.

4 The target eNB sends the HANDOVER REQUEST ACKNOWLEDGE message to the MME.

5 If indirect forwarding applies, the MME sends the Create Indirect Data Forwarding Tunnel Request message to the S-GW.

6 The S-GW replies to the MME with the Create Indirect Data Forwarding Tunnel Response message.

7 The MME sends the HANDOVER COMMAND message to the source eNB. 8 The source eNB creates the RRCConnectionReconfiguration message using the Target to Source Transparent Container IE contained in the HANDOVER COMMAND message and then sends it to the UE.

9 To send the PDCP and the HFN status of the E-RABs of which the PDCP status must be preserved, the source eNB sends the eNB/MME STATUS TRANSFER message to the target eNB via the MME. (Data forwarding can be possible even if it receives UE context release message during it receives End marker or timer limits.)

10 The source eNB must start forwarding the downlink data to the target eNB through the bearer which was determined to be used for data forwarding. This can be either direct or indirect forwarding.

11 The UE performs synchronization with the target eNB and connects to the target cell via a RACH. The target eNB responds with UL allocation and timing advance.

12 After having synchronized with the target cell, the UE notifies the target eNB that the handover has been completed using the RRCConnectionReconfigurationComplete message. The downlink packet forwarded from the source eNB can be sent to the UE. The uplink packet can also be sent from the UE to the S-GW via the target eNB.

13 The target eNB sends the HANDOVER NOTIFY message to the MME, which starts the timer to inform when to release the source eNB resources and the temporary resources used by the S-GW for indirect forwarding.

14 For each PDN connection, the MME sends the Modify Bearer Request message to the S-GW. The downlink packet is sent from the S-GW immediately to the target eNB.


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15 The S-GW sends the Modify Bearer Response message to the MME, and sends one or more 'end markers' packets to the previous path as soon as the path changes to assist in reordering packets in the target eNB. The source eNB sends one or more 'end markers' to the target eNB after all data from the source eNB gets forwarded to the target eNB.

16 If any of the conditions listed in Section 5.3.3.0 of TS 23.401 is met, the UE starts the Tracking Area Update procedure.

17 When the timer started at step 13 expires, the MME sends the UE CONTEXT RELEASE COMMAND message to the source eNB.

18 The source eNB releases the resources related to the UE and replies with the UE CONTEXT RELEASE COMPLETE message. (Data forwarding can be possible until source eNB send End Marker)

19 If indirect forwarding applies, the expiry of the timer started in the MME at Step 13 causes the MME to send to the S-GW the Delete Indirect Data Forwarding Tunnel Request message. This message allows release of temporary resources allocated at Step 5 for indirect forwarding.

20 The S-GW replies to the MME with the Delete Indirect Data Forwarding Tunnel Response message.



Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There is no activation/deactivation parameter for this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-PDCP-INF/RTRV-PDCP-INF Parameter

Description

FWD_END_TIMER

A period of time when PDCP of target eNB waits for end marker upon receiving a Handover Complete message and source eNB waits for end marker upon receiving a UE Context Release message. in milliseconds.


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Counters and KPIs Table below outlines the main counters and main Key Performance Indicators (KPIs) associated with this feature. Family Display Name

Type Name

Type Description

GTP Forward Traffic

CntGtpDLEnbS1Nor

The cumulated number of S1 downlink GTP packets during the basis call.

CntGtpULEnbS1Nor

The cumulated number of S1 uplink GTP packets during the basis call.

CntGtpDLEnbS1Fw

The cumulated number of forwarded packets received in the S1 downlink during the S1 handover.

CntGtpULEnbS1Fw

The cumulated number of packets forwarded to the S1 uplink during the S1 handover.

CntGtpDLEnbX2Fw

The cumulated number of forwarded packets received in the X2 downlink during the X2 handover.

CntGtpULEnbX2Fw

The cumulated number of packets forwarded to the X2 uplink during the X2 handover.

ByteGtpDLEnbS1Nor

The cumulated bytes of S1 downlink GTP packets during the basis call.

ByteGtpULEnbS1Nor

The cumulated bytes of S1 uplink GTP packets during the basis call.

ByteGtpDLEnbS1Fw

The cumulated bytes of forwarded packets received in the S1 downlink during the S1 handover.

ByteGtpULEnbS1Fw

The cumulated bytes of packets forwarded to the S1 uplink during the S1 handover.

ByteGtpDLEnbX2Fw

The cumulated bytes of forwarded packets received in the X2 downlink during the X2 handover.

ByteGtpULEnbX2Fw

The cumulated bytes of packets forwarded to the X2 uplink during the X2 handover.

ThruGtpDLEnbS1Nor

The average throughput of S1 downlink GTP packet in the basis call

ThruGtpULEnbS1Nor

The average throughput of S1 uplink GTP packet in the basis call

ThruGtpDLEnbS1Fw

The average throughput of forwarded packets received in the S1 downlink during the S1 handover.

ThruGtpULEnbS1Fw

The average throughput of packets forwarded to the S1 uplink during the S1 handover.

ThruGtpDLEnbX2Fw

The average throughput of forwarded packets received in the X2 downlink during the X2 handover.

ThruGtpULEnbX2Fw

The average throughput of packets forwarded to the X2 uplink during the X2 handover.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[3] 3GPP 36.413: E-UTRA and E-UTRAN; S1 Application Protocol (S1AP) [4] 3GPP 36.423: E-UTRA and E-UTRAN; X2 Application Protocol (X2AP)


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LTE-SW1007, Inter-Frequency Handover INTRODUCTION Inter-frequency handover is mobility control functionality between cells that use different frequency band. The eNB provides UEs with measurement gap information in order for the UEs to perform inter frequency search. Measurement Gap avoids scheduling of data for the UE during inter frequency scan periods. When a user moves to a neighboring carrier area, the eNB processes the interfrequency handover procedure to ensure the service continuity in the LTE. The eNB refers the inter-frequency measurement report by the UE for handover to the neighboring carrier areas. After receiving the inter-frequency measurement result by the UE, the eNB selects the handover target cell and processes the handover preparation with a target cell/eNB. When the handover preparation with a target cell/eNB is successful, the eNB instructs the UE to perform the inter-frequency handover. The UE performs handover to the target cell specified by the eNB to continue the service.

BENEFIT Operator can provide connected mobility to its subscribers between cells which have a different center frequency.

Users in connected state can be moving within E-UTRAN, with change of serving cell.

DEPENDENCY Prerequisite Features: LTE-SW1003 (Intra-eNB handover), LTE-SW1004 (S1 handover), LTE-SW1005 (X2 handover)

LIMITATION None

SYSTEM IMPACT Interdependencies between Features This feature can be activated only when the LTE-SW1003 (Intra-eNB handover) or LTE-SW1004 (S1 Handover) or LTE-SW1005 (X2 Handover) feature is enabled.


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FEATURE DESCRIPTION When a connected UE is moved to an overlapped area between the cells, the handover is performed according to the standard procedures described in the following separate FDDs, depending on the neighbor configuration status:

Intra-eNB handover (Refer to LTE-SW1003) S1 handover (Refer to LTE-SW1004) X2 handover (Refer to LTE-SW1005) The eNB sends the measurement configuration information to the UE via a dedicated RRCConnectionReconfiguration message when the UE is in the RRC_CONNECTED status. The UE reports measured information to the eNB in accordance with the measurement configuration provided by the eNB. The following parameters are included in the measurement configuration provided to the UE. Parameter

Description

Measurement objects

The object on which the UE must perform measurements. The measurement object is a single E-UTRA carrier frequency for interfrequency.

Reporting configuration

The reporting configuration list, each item of which consists of the reporting criterion and the report format. The reporting criterion is the reference information that the UE triggers to send a measurement report. It is either a periodical event or a single event. The report format includes the quantity information and the related information included by the UE in a measurement report (for example, number of cells to report).

Measurement identities

The measurement identity list, each item of which is associated with one measurement object and one reporting configuration.

Quantity configuration

Quantity configuration includes the measurement quantities and related filtering information for all event evaluation, each of which is set by the RAT type.

Measurement gaps

The period of time during which the UE performs measurements. UL/DL data transmission is restricted during this period.

Triggering quantity option of A2/A3/A4/A5 Event is extended to have 'both RSRP and RSRQ' option for both service-based and coverage-based handover. Triggering quantity option of A1/A3/A4/A5/B2 Event is extended to have 'following triggering quantity occurring at A2 event' option for both service-based and coverage-based handover. The table below lists the measurement event types that can be set currently in the eNB, and provides descriptions of them. Event Type

Description

A1

Performs the Measurement Gap Deactivation.

A2

Performs the Measurement Gap Activation.

A3

Performs the Inter LTE Handover or the Automatic Neighbor Relation (ANR).


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After UE measures the RSRP of a connected carrier becomes lower than the configured threshold, it sends a measurement report event type A2 to the serving eNB (If all Inter-frequency target cells listed Forbidden TAC in RestrictionList, eNB don't send A2 to UE.). Then the eNB sends UE an RRCConnectionReconfiguration message to activate UE measurement gap. This allows UE searching for the signal of another frequency when the UE moves to a boundary area between cells. When the serving eNB receives UE measurement event type A1, it sends UE another RRCConnectionReconfiguration message to deactivate UE measurement gap. (If A2 set to inactive for LTE Handover, eNB don't set to A3, A4 and A5 measurements for Inter-frequency handover.) When the measurement gap is activated, the eNB does not transmit any signal or data to the UE while the UE performs measurement. To reduce the idle time when the system efficiency is degraded, distribute measurement gap per UE as much as possible. The gap pattern of measurement gap configuration is expressed in {0, 1} and the gap length and repetition period are shown as below. IF the Gap Pattern Id is 0, the gapOffset is (0...39). If the Gap Pattern Id is 1, the gapOffset is (0...79). Gap Pattern Id

Transmission Gap Length (TGL, ms)

Transmission Gap Repetition Period (TGRP, ms)

Minimum available time for inter-frequency and interRAT measurements during 480 ms period (Tinter1, ms)

0

6

40

60

1

6

80

30

If the UE searches for a signal in another frequency bandwidth for a long time using the configured measurement gap pattern, the measurement report containing the A3 event will be transmitted to the source cell to perform handover to the cell. When the source eNB receives the measurement report, the inter-frequency handover is complete through the intra-eNB/X2/S1 handover. Refer to separate features for detail procedures how eNB carries out the inter-eNB S1 handover (LTE-SW1004) or inter-eNB X2 handover (LTE-SW1005) once eNB decides a handover is granted based on radio resources management information. Measurement Gap Activation The operator configures parameter (for example, threshold and hysteresis) values for the EVENT A2 measurement report of the UE.

To execute measurement for the inter-frequency cell, the UE requests the measurement gap to the eNB if the measurement gap is not configured.

The measurement gap configuration request of the UE is performed by the EVENT A2 measurement reporting. The specifications for the Event A2 are shown below Event A2 (Serving becomes worse than threshold) The UE shall: 1consider the entering condition for this event to be satisfied when condition A2-1, as specified below, is fulfilled; 2consider the leaving condition for this event to be satisfied when condition A2-2, as specified below, is fulfilled; eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 4 Mobility Control oInequality A2-1 (Entering condition) oInequality A2-2 (Leaving condition) The variables in the formula are defined as follows: Ms is the measurement result of the serving cell, not taking into account any offsets. Hys is the hysteresis parameter for this event (that is, hysteresis as defined within reportConfigEUTRA for this event). Thresh is the threshold parameter for this event (that is, a2-Threshold as defined within reportConfigEUTRA for this event). Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ. Hys is expressed in dB. Thresh is expressed in the same unit as Ms.

Measurement Gap Deactivation The operator configures parameter (for example, threshold and hysteresis) values for the EVENT A1 measurement report of the UE.

If the UE determines that the measurement for inter-frequency cell is not necessary but the measurement gap is configured now, it requests the release of measurement gap to the eNB.

The measurement gap release request of the UE is performed by the EVENT A1 measurement reporting. The specifications for the Event A1 are shown below. Event A1 (Serving becomes better than threshold) The UE shall: 1consider the entering condition for this event to be satisfied when condition A1-1, as specified below, is fulfilled; 2consider the leaving condition for this event to be satisfied when condition A1-2, as specified below, is fulfilled; oInequality A1-1 (Entering condition) EMBED Equation. 3 oInequality A1-2 (Leaving condition) EMBED Equation. 3 The variables in the formula are defined as follows: Ms is the measurement result of the serving cell, not taking into account any offsets. Hys is the hysteresis parameter for this event (that is, hysteresis as defined within reportConfigEUTRA for this event). Thresh is the threshold parameter for this event (that is, a1-Threshold as defined within reportConfigEUTRA for this event). Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ. Hys is expressed in dB. Thresh is expressed in the same unit as Ms.

RSRP + RSRQ Trigger Quantity Configuration Current design supports configuring either RSRP or RSRQ as trigger quantity for a measurement event. This means that the current design does not allow operator to configure two triggers, one with RSRP and another with RSRQ for same measurement event. In current design trigger quantity configuration options available for A1, A2, A3, A4, A5 and B2 events are same, either rsrp or rsrq. The RSRP + RSRQ Trigger quantity enhancement allows operator to configure both RSRP and RSRQ as trigger quantity for A2 measurement event for purposes related to coverage based Handover (CHG-EUTRA-A2CNF) and Service based handover (CHG-EUTRA-A2CNFQ). The new trigger quantity option ‟ci_both‟ provides the option for the operator to configure RSRP and RSRQ as trigger eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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quantity for an A2 event for specific purposes related to handover and re-direction. Below table shows the newly added trigger quantity. Note that the purposes for Ca, CaPeriodicMr, CaInterFreq, and MDT do not support the new trigger quantity. CHG-EUTRA-A2CNF/CHG-EUTRA-A2CNFQ: PURPOSE

Possible values for TRIGGER_QUANITY

LteHo, LteBlind, IRatHo, IRatBlind, Srvcc

ci_rsrp, ci_rsrq, ci_both

Ca, CaPeriodicMr, CaInterFreq, Mdt

ci_rsrp, ci_rsrq

When operator configures ci_both as the trigger quantity for A2 event, eNB will configure both RSRP and RSRQ as trigger quantities for A2 event to UE in a single RRC Reconfiguration message. This configuration will result in two different reportConfigId for same A2 event, one corresponding to RSRP and other corresponding to RSRQ. Similarly, this will result in two different measId for same A2 event as well. Depending on which condition (RSRP or RSRQ) is met first, UE will send either of the measIds to eNB in RRC MeasurementReport message. Once the UE is configured with both RSRP and RSRQ as triggering quantity, UE sends measurement report with measurement identity indicating which triggering quantity threshold is met (ie. either RSRP threshold is met or RSRQ threshold is met). Once A2 event is reported, eNB shall be able to configure subsequent measurement events (A1, A3, A4, A5 or B2) with the trigger quantity as - only RSRP or only RSRQ or same trigger quantity which caused A2 event reporting. Operator should be able to configure the trigger quantities of A1, A3, A4, A5 and B2 as RSRP or RSRQ or the same trigger quantity which is reported in A2 measurement report (ci_followA2Event). The new trigger quantity (ci_followA2Event) is available only for purposes related to A2 event and related to handover and re-direction. Below tables shows the specific purposes for which the new trigger quantity is applicable for each event. If the operator selects „ci_followA2Event‟ as trigger quantity for A1/A3/A4/A5/B2 event, then eNB configures A1/A3/A4/A5/B2 event to UE with the same trigger quantity which actually triggered the A2 event. In case of Intra-LTE inter-frequency handover, eNB configures A2 event to UE and when UE reports A2 event, A5 event is configured to ensure that the inter frequency neighbor cell is above an acceptable threshold before handover and when UE reports A5 event, UE is handed over to the target cell. Operator configures the A2 and A5 thresholds for intra-LTE inter-frequency handover using the purpose value „IntraLteHO‟. The new trigger quantities for A2 and A5 are available for „IntraLteHO‟ purpose. Operator can configure trigger quantity for A2 as „ci_both‟ for intra LTE handover. If A2 event was configured as „ci_both‟, and if RSRQ threshold was met by the UE, UE sends measurement report message with a measId indicating RSRQ threshold condition was met. In this case, eNB configures A5 event with RSRQ as triggering quantity if A5 trigger quantity is configured as „ci_followA2Event‟ for the same purpose. Example call flow for intra LTE inter frequency handover with RSRP + RSRQ trigger quantity is shown below. The new trigger quantities are not available for measurements not related to TM load balancing and carrier aggregation. For example, when configuring thresholds for A4 measurement purpose „InterFrequencyLb‟, the new trigger quantity eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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„ci_followA2Event‟ will not available.

Table below outlines new trigger quantity option for A1 event. CHG-EUTRA-A1CNF/CHG-EUTRA-A1CNFQ: PURPOSE


MeasGapDeact

ci_rsrp, ci_rsrq, ci_followA2Event

CaInterFreq, CaPeriodicMr

ci_rsrp, ci_rsrq



LteHo, LteBlind, IRatHo, IRatBlind, Srvcc

ci_rsrp, ci_rsrq, both

Ca, CaPeriodicMr, Mdt, CaInterFreq, InterFreqAnrTrigger

ci_rsrp, ci_rsrq


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IntraLteHandover

ci_rsrp, ci_rsrq, ci_followA2Event, both

ReportStrongestCells, InterFrequencyLb, CaInterFreq, InterFrequencyCre, PeriodicMr

ci_rsrp, ci_rsrq



IntraLteHandover


Ca, ANR_Specific, Sendback, InterFrequencyLb, ArpHandover, OnDemandHandover, InterFrequencySPID

ci_rsrp, ci_rsrq



IntraLteHandover


CaInterFreq, InterFrequencyMbms, ArpHandover, OnDemandHandover, InterFrequencySPID

ci_rsrp, ci_rsrq

Table below outlines new trigger quantity option for HRPD B2 event. CHG-HRPD-B2CNF/CHG-HRPD-B2CNFQ: PURPOSE


InterRatHandover, Srvcc


Table below outlines new trigger quantity option for 1xRTT B2 event. CHG-C1XRTT-B2CNF/CHG-C1XRTT-B2CNFQ: PURPOSE


InterRatHandover, Srvcc




Run CHG-EUTRA-A2CNF and set ACTIVE_STATE corresponding to PURPOSE (A2PurposeIntraLteHandover) to active or


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Run CHG-EUTRA-A3CNF and set ACTIVE_STATE corresponding to PURPOSE (A3PurposeIntraLteHandover) to active. Deactivation Procedure To deactivate this feature, do the following:

Select 1 event to use to inactivate Inter Frequency Handover. Run CHG-EUTRA-A2CNF and set ACTIVE_STATE corresponding to PURPOSE (A2PurposeIntraLteHandover) to Inactive or Run CHG-EUTRA-A3CNF and set ACTIVE_STATE corresponding to PURPOSE (A3PurposeIntraLteHandover) to Inactive.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-EUTRA-A2CNF/RTRV-EUTRA-A2CNF Parameter

Description

PURPOSE

This parameter is the purpose of using Event A3. LteHo: Used for Gap Activate. LteBlind: Used for Blind HO. IRatHo: Used for IRAT HO. IRatBlind: Used for IRAT Blind HO. Ca: Used for Carrier Aggregation. CaPeriodicMr: Used for Add Smart Carrier Aggregation Periodic Measure Config. Srvcc: Used for Single Radio Voice Call Continuity. Mdt: Used for Minimization of Drive Tests. CaInterFreq: Used for Inter Frequency Carrier Aggregation. InterFreqAnrTrigger: Used for Inter Frequency Anr. InterRatAnrTrigger: Used for Inter Rat Anr.

ACTIVE_STATE

This parameter indicates whether event A2 is enabled/disabled per target frequency. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. Inactive: Event A2 is not used. Active: Event A2 is used. If HO of the target frequency is not needed in the site, this is inactive.


Description

PURPOSE

This parameter is the purpose of using Event A3. IntraLteHandover: Performs handover.


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Description ReportStrongestCells: Performs the ANR operation. IntraFrequencyLb: Performs Intra Frequency Load Balancing. CaInterFreq: Performs InterFrequency Carrier Aggregation. IntraFrequencyCre: Performs IntraFrequency CRE. PeriodicMr: Performs Periodic Measurement Report for eICIC.

ACTIVE_STATE



Description

PURPOSE

This parameter is used to set up the TriggerQuantity of Event A1 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq/followA2Event. An UE transmits Event A1 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A1_THRESHOLD_RSRP is used. If it is RSRQ, the A1_THRESHOLD_RSRQ is used. If the TRIGGER_QUANTITY is FOLLOW_A2_EVENT, It will follow the TRIGGER_QUANTITY of the previously received A2 event with handover purpose. (it is noted that this configuration is only available if the A1 purpose is handover related case, that is, MeasGapDeact) This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: The trigger quantity of this event is set RSRP. rsrq: The trigger quantity of this event is set RSRQ. followA2Event: The trigger quantity of this event follows the trigger quantity of the previously received A2 event.

ACTIVE_STATE

This parameter indicates whether event A1 is enabled/disabled per target frequency. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. Inactive: Event A1 is not used. Active: Event A1 is used. If HO of the target frequency is not needed in the site, this is inactive.

A1_THRESHOLD_RSRP

This parameter is the RSRP threshold for Event A1 which is used to perform measurement gap deactivation. Event A1 occurs when serving becomes better than threshold. The UE could measure either Reference Signal Received Power (RSRP) or Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or idle to active). To avoid overload, a new setting will not be updated to the current active UEs. The lower the parameter is, in the lower signal strength measurement gap is deactivated. This parameter is set to a value between 0-97 using the unit defined in the 3GPP TS36.331. Value used when the TRIGGER QUANTITY is set to RSRP. The actual RSRP measurement value must be set to A1_THRESHOLD_RSRP-140 (dBm). [Related Specifications] 3GPP TS36.331

A1_THRESHOLD_RSRQ

This parameter is the RSRP threshold for Event A1 which is used to perform measurement gap deactivation. Event A1 occurs when serving becomes better


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Description than threshold. The UE could measure either Reference Signal Received Power (RSRP) or Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or idle to active). To avoid overload, a new setting will not be updated to the current active UEs. The lower the parameter is, in the lower signal strength measurement gap is deactivated. This parameter is set to a value between 0-97 using the unit defined in the 3GPP TS36.331. Value used when the TRIGGER QUANTITY is set to RSRP. The actual RSRP measurement value must be set to A1_THRESHOLD_RSRP-140 (dBm). [Related Specifications] 3GPP TS36.331

TIME_TO_TRIGGER

This parameter is the timeToTrigger value for the Event A1. The timeToTrigger is the time which should be satisfied for the UE to trigger the measurement report. The event A1 occurs only when a specific threshold meet a threshold during the period of TIME_TO_TRIGGER and the TIME_TO_TRIGGER can be set to a value 0-5120 ms as defined in the TS.36.331. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. [Related Specifications] 3GPP TS36.331

TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A1 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq/followA2event. An UE transmits Event A1 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A1_THRESHOLD_RSRP is used. If it is RSRQ, the A1_THRESHOLD_RSRQ is used. If it is followA2event, A2 event's TRIGGER_QUANTITY is used for A1 event. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: The trigger quantity of this event is set RSRP. rsrq: The trigger quantity of this event is set RSRQ. followA2event: The trigger quantity of this event is set A2 event TRIGGER_QUANTITY.


Description

PURPOSE

This parameter is the purpose of using the Event A2 per cell. It is used to activate the measurement gap as default. LteHo: Used for Gap Activate. LteBlind: Used for Blind HO. IRatHo: Used for IRAT HO. IRatBlind: Used for IRAT Blind HO. Ca: Used for Carrier Aggregation. CaPeriodicMr: Used for Add Smart Carrier Aggregation Periodic Measure Config. Srvcc: Used for Single Radio Voice Call Continuity. Mdt: Used for Minimization of Drive Tests. CaInterFreq: Used for Inter Frequency Carrier Aggregation. InterFreqAnrTrigger: Used for Inter Frequency Anr. InterRatAnrTrigger: Used for Inter Rat Anr.

ACTIVE_STATE

This parameter indicates whether event A2 is enabled/disabled per target frequency. This change will be applied to the UE from next RRC signaling


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Description procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. Inactive: Event A2 is not used. Active: Event A2 is used. If HO of the target frequency is not needed in the site, this is inactive.

A2_THRESHOLD_RSRP

This parameter is the RSRP threshold for Event A2 which is used to perform measurement gap activation or redirection. In the serving cell, the measurement is triggered by an event A2 that means the quality of EUTRAN DL reference signal becomes worse than the absolute threshold. The UE could measure either Reference Signal Received Power (RSRP) or Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. The higher the parameter is, the stronger signal strength measurement gap is activated and too frequent measurement gap activation can impact service experience. The lower the parameter is, the weaker signal strength measurement gap is activated and the later measurement gap activation can impact HO success rate.

A2_THRESHOLD_RSRQ

This parameter is the RSRQ threshold for Event A2 which is used to perform measurement gap activation or redirection. In the serving cell, the measurement is triggered by an event A2 that means the quality of EUTRAN DL reference signal becomes worse than the absolute threshold. The UE could measure either Reference Signal Received Power (RSRP) or Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the stronger signal strength measurement gap is activated and too frequent measurement gap activation can impact service experience. The lower the parameter is, the weaker signal strength measurement gap is activated and the later measurement gap activation can impact HO success rate.

TIME_TO_TRIGGER


TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A2 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq. An UE transmits Event A2 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A2_THRESHOLD_RSRP is used. If it is RSRQ, the A2_THRESHOLD_RSRQ is used. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: The trigger quantity of this event is set RSRP. rsrq: The trigger quantity of this event is set RSRQ. both: The trigger quantity of this event is set RSRQ and RSRP.

Parameter Descriptions of CHG-EUTRA-A3CNF/RTRV-EUTRA-A3CNF eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

PURPOSE


ACTIVE_STATE


A3_OFFSET


A3_OFFSET_FOR_RSRQ

RSRQ threshold used for triggering the EUTRA measurement report for Event A3.

TIME_TO_TRIGGER


TRIGGER_QUANTITY



Description

PURPOSE

This parameter is the purpose of using Event A4. IntraLteHandover: handover is executed ANR_Specific:the ANR operation is executed CA: SCELL is configured Sendback: the Sendback operation is executed InterFrequencyLb: the Active Load Balancing operation is executed ArpHandover: Enable inter frequency handover function for UEs that have a specific ARP OnDemandHandover: Enable the forced handover triggering by operator InterFrequencySPID: inter-frequency handover is executed for specific SPID with handover mobility option. Spare_2: it is not used at this moment because it is reserved for future use.

ACTIVE_STATE

This parameter indicates whether event A4 is enabled/disabled per target frequency. If this is set to Inactive, the Event A4 is not configured. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. Inactive: Event A4 is not used. Active: Event A4 is used. If HO of the target frequency is not needed in the site, this is inactive.

A4_OFFSET_FOR_RSRP

This parameter is the RSRP threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter


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Description is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment. [Related Specifications] 3GPP TS 36.331

A4_OFFSET_FOR_RSRQ

This parameter is the RSRQ threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on the RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment. [Related Specifications] 3GPP TS 36.331

TIME_TO_TRIGGER


TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A4 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq. An UE transmits Event A4 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A4_THRESHOLD_RSRP is used. If it is RSRQ, the A4_THRESHOLD_RSRQ is used. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: It indicates that RSRP is used for triggerQuantity. rsrq: It indicates that RSRQ is used for triggerQuantity. followA2event: It indicates that the value of TriggerQuantity corresponds with the value of A2 Event triggerQuantity. both: It indicates that RSRP and RSRQ are used for triggerQuantity.


Description

PURPOSE

This parameter is the purpose of using Event A5. IntraLteHandover: Used for Intra LTE Handover. CaInterFreq: Performs Inter frequency handover for Carrier Aggregation(CA) UE InterFrequencyMbms: Inter frequency handover to get MBMS service ArpHandover: Enable Inter frequency handover function for UEs that have a specific ARP OnDemandHandover: Enable the forced handover triggering by operator InterFrequencySPID: Inter frequency handover for the specific SPID with handover mobility option IdcHandover: Handover for Interference Avoidance in IDC.


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Description Spare_2: Reserved

ACTIVE_STATE

Whether to use the Event A5. Inactive: Event A5 is not used. Active: Event A5 is used.

A5_THRESHOLD2_RSRP


A5_THRESHOLD2_RSRQ


TIME_TO_TRIGGER


TRIGGER_QUANTITY



Type Name

Type Description

Outgoing Inter-frequency Handover with Measurement Gap

InterFreqMeasGapOutAtt

Outgoing inter-frequency handover (measurement gap assisted) attempt count

InterFreqMeasGapOutPrepSu cc

Outgoing inter-frequency handover (measurement gap assisted) preparation success count

InterFreqMeasGapOutSucc

Outgoing inter-frequency handover (measurement gap assisted) execution success count

InterFreqMeasGapOutPrepFai l_CP_CC_FAIL

Preparation fails due to reset notification (eNB failure or block restart) from ECCB or by the ECCB block during the outgoing interfrequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_S1AP_CU_FAIL

Preparation fails due to the S1AP specification cause during the outgoing interfrequency handover (measurement gap assisted) preparation.


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Type Name

Type Description

InterFreqMeasGapOutPrepFai l_S1AP_LINK_FAIL

Preparation fails due to the S1 SCTP link failure during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_S1AP_RP_TO

Preparation fails due to S1AP relocprep timeout (not received) during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_S1AP_SIG_FAIL

Preparation fails due to receiving S1AP signaling during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_X2AP_CU_FAIL

Preparation fails due to the X2AP specification cause during the outgoing interfrequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_X2AP_LINK_FAIL

Preparation fails due to the X2 SCTP link failure during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_X2AP_RP_TO

Preparation fails due to X2AP relocprep timeout (not received) during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutPrepFai l_X2AP_SIG_FAIL

Preparation fails due to receiving X2AP signaling during the outgoing inter-frequency handover (measurement gap assisted) preparation.

InterFreqMeasGapOutFail_CP _CC_TO

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_CP _CC_FAIL

A call is released due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_UP _GTP_FAIL

A call is released due to the failure in the GTP block during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_UP _MAC_FAIL

A call is released due to the failure in the MAC block during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_UP _PDCP_FAIL

A call is released due to the failure in the PDCP block during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_UP _RLC_FAIL

A call is released due to the failure in the RLC block during the outgoing interfrequency handover (measurement gap assisted) execution.


372


Outgoing Handover without Measurement Gap

Type Name

Type Description

InterFreqMeasGapOutFail_RR C_SIG_FAIL

A call is released due to receiving RRC signaling during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_S1 AP_CU_FAIL

A call is released due to the S1AP specification cause during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_S1 AP_LINK_FAIL

A call is released due to the S1 SCTP link failure during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_S1 AP_RO_TO

A call is released due to the S1AP relocoverall timeout (not received) during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_S1 AP_SIG_FAIL

A call is released due to receiving S1AP signaling during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_X2 AP_CU_FAIL

A call is released due to the X2AP specification cause during the outgoing interfrequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_X2 AP_LINK_FAIL

A call is released due to the X2 SCTP link failure during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_X2 AP_RO_TO

A call is released due to the X2AP relocoverall timeout (not received) during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqMeasGapOutFail_X2 AP_SIG_FAIL

A call is released due to receiving X2AP signaling during the outgoing inter-frequency handover (measurement gap assisted) execution.

InterFreqOutWithGapCnt

Outgoing Inter-Frequency Handover with Measurement Gap collection count

InterFreqOutWithGapTargetE arfcnDl

TargetEarfcnDl of which collection is requested

InterFreqNoMeasGapOutAtt

Outgoing inter-frequency handover (no measurement gap assisted) attempt count

InterFreqNoMeasGapOutPrep Succ

Outgoing inter-frequency handover (no measurement gap assisted) preparation success count

InterFreqNoMeasGapOutSucc

Outgoing inter-frequency handover (no measurement gap assisted) execution success count

InterFreqNoMeasGapOutPrep Fail_CP_CC_FAIL

Preparation fails due to reset notification (eNB failure or block restart) from ECCB or by the ECCB block during the outgoing interfrequency handover (no measurement gap assisted) preparation.


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Type Name

Type Description

InterFreqNoMeasGapOutPrep Fail_S1AP_CU_FAIL

Preparation fails due to the S1AP specification cause during the outgoing interfrequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_S1AP_LINK_FAIL

Preparation fails due to the S1 SCTP link failure during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_S1AP_RP_TO

Preparation fails due to S1AP relocprep timeout (not received) during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_S1AP_SIG_FAIL

Preparation fails due to receiving S1AP signaling during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_X2AP_CU_FAIL

Preparation fails due to the X2AP specification cause during the outgoing interfrequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_X2AP_LINK_FAIL

Preparation fails due to the X2 SCTP link failure during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_X2AP_RP_TO

Preparation fails due to X2AP relocprep timeout (not received) during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutPrep Fail_X2AP_SIG_FAIL

Preparation fails due to receiving X2AP signaling during the outgoing inter-frequency handover (no measurement gap assisted) preparation.

InterFreqNoMeasGapOutFail_ CP_CC_TO

A call is released due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ CP_CC_FAIL

A call is released due to reset notification (eNB failure or bloc restart) from ECMB or by the ECCB block during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ UP_GTP_FAIL

A call is released due to the failure in the GTP block during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ UP_MAC_FAIL

A call is released due to the failure in the MAC block during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ UP_PDCP_FAIL

A call is released due to the failure in the PDCP block during the outgoing interfrequency handover (no measurement gap assisted) execution.


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MOBILITY (KPI)

Type Name

Type Description

InterFreqNoMeasGapOutFail_ UP_RLC_FAIL

A call is released due to the failure in the RLC block during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ RRC_SIG_FAIL

A call is released due to receiving RRC signaling during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ S1AP_CU_FAIL

A call is released due to the S1AP specification cause during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ S1AP_LINK_FAIL

A call is released due to the S1 SCTP link failure during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ S1AP_RO_TO

A call is released due to the S1AP relocoverall timeout (not received) during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ S1AP_SIG_FAIL

A call is released due to receiving S1AP signaling during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ X2AP_CU_FAIL

A call is released due to the X2AP specification cause during the outgoing interfrequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ X2AP_LINK_FAIL

A call is released due to the X2 SCTP link failure during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ X2AP_RO_TO

A call is released due to the X2AP relocoverall timeout (not received) during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqNoMeasGapOutFail_ X2AP_SIG_FAIL

A call is released due to receiving X2AP signaling during the outgoing inter-frequency handover (no measurement gap assisted) execution.

InterFreqOutWithOutGapCnt

Outgoing Inter-Frequency Handover without Measurement Gap collection count

InterFreqOutWithOutGapTarg etEarfcnDl

TargetEarfcnDl of which collection is requested

EutranMobilityHoInter

Probability that an end-user successfully completes a handover to a separate eNB of the same frequency

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP) [4] 3GPP TS36.423 Evolved Universal Terrestrial Radio Access Network (EUTRAN); X2 Application Protocol (X2AP)


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LTE-SW1014, RLF Triggered Handover INTRODUCTION This feature minimizes rejection of the RRC Reestablishment (RRE) request when the UE requests for RRE due to the Radio Link Failure (RLF). When the eNB that has no context receives a request for RRE, the eNB can accept RRE of the UE by securing the UE context through signaling with the serving eNB.

BENEFIT If the eNB that has no UE context is requested for RRE due to the RLF, the eNB can hand over the RRE request through signaling with the serving eNB.

DEPENDENCY HW dependency This feature can operate only between Samsung eNBs.

Prerequisite Features LTE-SW1005 (X2 Handover)

LIMITATION None

SYSTEM IMPACT Interdependencies between Features This feature can be activated only when the LTE-SW1005 (X2 Handover) feature is enabled.

FEATURE DESCRIPTION The UE, which enters into an area where the wireless environment is not good requests for RRE. At this point, if not the existing serving eNB but the eNB that requests for RRE by the UE, the RRE request of the UE is rejected since the eNB has no UE context information.


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However, this feature is implemented to avoid the RRE rejection as much as possible through handover signaling as follows.

1 If the target eNB2 that receives the RRE request of UE cannot find a context of the UE, the target eNB2 notifies the source eNB1 which the RLF has occurred. The target eNB2 waits a HO request from the source eNB1 and a response of UE’s RRE request will be delayed if the source eNB1 is a Samsung eNB. The target eNB2 can identify that the source eNB1 is a Samsung eNB from the exchange information during X2 setup procedure.

2 Once the source eNB1 receives the RLF indication it confirms that the target eNB2 is a Samsung eNB. The eNB1 performs HO preparation by transmitting a handover request to the eNB2. Even if the target cell is unknown neighbour cell, this HO preparation can be possible if there has X2 connectivity with the target eNB2, and the UE’s handover to the target cell is allowable based on the information about the UE specific access restrictions and target cell’s broadcast PLMNs.


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In this step, if performing the following procedure with the RLF UE, the source eNB1 does not perform RLF triggered HO, that is, eNB1 does not send X2 HO Request: oduring UE Context Release; or oduring RRC Connection Reconfiguration with the RLF UE. Exceptionally, if the purpose of the ongoing RRC Connection Reconfiguration is UL resource reallocation, the source eNB1 ends the ongoing procedure and will perform RLF triggered HO, that is, eNB1 will send X2 HO Request.

3 The eNB2 transmits a response to RRE of the UE by securing the context of the UE and ensures that it is normally completed (An eNB transmits RRE message to UE when transmitting the Handover Acknowledge message to MME in RLF triggered Handover procedure.).


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature Activation Procedure Run HANDOVER_BY_RLF of CHG-HO-OPT to ON to use this function, then run INIT-SW(eccb) or INIT-SCTP(X2) for X2-Reset. Deactivation Procedure Run HANDOVER_BY_RLF of CHG-HO-OPT to OFF to use this function.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters Run CHG-HO-OPT and set HANDOVER_BY_RLF to ON to use this function. Parameter description of CHG-HO-OPT/RTRV-HO-OPT Parameter

Description

HANDOVER_BY_RLF

Whether to use Inter-eNB RRE function Off: not use Inter-eNB RRE On: use Inter-eNB RRE

Configuration Parameters There are no specific parameters to configure this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Counters and KPIs RLF triggered handover will be pegged as the following X2 Handover counters with index HoCause = Time Critical Handover. Family Display Name

Type Name

Type Description

X2 Handover Out

InterX2OutAtt

Attempt count for X2 handover from SeNB.

InterX2OutPrepSucc

Success count for X2 handover preparation from SeNB.

InterX2OutSucc

Success count for X2 handover execution from SeNB.

InterX2OutPrepFail_CP_CC_FAIL


InterX2OutPrepFail_S1AP_LINK_F AIL


InterX2OutPrepFail_S1AP_SIG_FA IL


InterX2OutPrepFail_X2AP_CU_FAI L


InterX2OutPrepFail_X2AP_LINK_F AIL


InterX2OutPrepFail_X2AP_RP_TO

Preparation fails due to X2AP relocprep timeout (not received) during the inter X2 handover preparation.

InterX2OutPrepFail_X2AP_SIG_FA IL


InterX2OutFail_CP_CC_TO


InterX2OutFail_CP_CC_FAIL


InterX2OutFail_UP_GTP_FAIL


InterX2OutFail_UP_MAC_FAIL


InterX2OutFail_UP_PDCP_FAIL


InterX2OutFail_UP_RLC_FAIL


InterX2OutFail_RRC_SIG_FAIL



380


X2 Handover In

Type Name

Type Description

InterX2OutFail_S1AP_CU_FAIL


InterX2OutFail_S1AP_LINK_FAIL


InterX2OutFail_S1AP_SIG_FAIL


InterX2OutFail_X2AP_CU_FAIL


InterX2OutFail_X2AP_LINK_FAIL


InterX2OutFail_X2AP_RO_TO

A call is released due to X2AP RelocOverall timeout (not received) during the inter X2 handover execution.

InterX2OutFail_X2AP_SIG_FAIL


InterX2OutCnt

X2 Handover Out collection count

InterX2OutCid

tcID of which collection is requested

InterX2InAtt

The number of attempts for X2 handover in TeNB

InterX2InPrepSucc

The number of successes for X2 handover preparation in TeNB

InterX2InSucc

The number of successes for X2 handover execution in TeNB

InterX2InPrepFail_CP_CC_TO

Preparation fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, GTP) during the inter X2 handover preparation.

InterX2InPrepFail_CP_CC_FAIL


InterX2InPrepFail_UP_GTP_FAIL

Preparation fails due to internal failure in the GTP block during the inter X2 handover preparation.

InterX2InPrepFail_UP_MAC_FAIL

Preparation fails due to internal failure in the MAC block during the inter X2 handover preparation.

InterX2InPrepFail_UP_PDCP_FAIL

Preparation fails due to internal failure in the PDCP block during the inter X2 handover preparation.

InterX2InPrepFail_UP_RLC_FAIL

Preparation fails due to internal failure in the RLC block during the inter X2 handover preparation.

InterX2InPrepFail_CP_BH_CAC_F AIL

Preparation fails due to insufficient backhaul-based eNB resources during the inter X2 handover preparation.


381


Type Name

Type Description

InterX2InPrepFail_CP_CAPA_CAC _FAIL

Preparation fails due to insufficient capacitybased eNB resources during the inter X2 handover preparation.

InterX2InPrepFail_CP_QOS_CAC_ FAIL

Preparation fails due to insufficient QoSbased eNB resources during the inter X2 handover preparation.

InterX2InPrepFail_S1AP_LINK_FAI L


InterX2InPrepFail_S1AP_SIG_FAIL


InterX2InPrepFail_X2AP_CU_FAIL


InterX2InPrepFail_X2AP_LINK_FAI L


InterX2InPrepFail_X2AP_SIG_FAIL


InterX2InFail_CP_CC_TO


InterX2InFail_CP_CC_FAIL


InterX2InFail_UP_GTP_FAIL


InterX2InFail_UP_MAC_FAIL


InterX2InFail_UP_PDCP_FAIL


InterX2InFail_UP_RLC_FAIL


InterX2InFail_RRC_HC_TO

A call is released due to HO command timeout (not received) during the inter X2 handover execution.

InterX2InFail_RRC_SIG_FAIL


InterX2InFail_S1AP_CU_FAIL


InterX2InFail_S1AP_LINK_FAIL


InterX2InFail_S1AP_PATH_TO

A call is released due to S1AP path switch


382


Type Name

Type Description timeout (not received) during the inter X2 handover execution.

InterX2InFail_S1AP_SIG_FAIL


InterX2InFail_X2AP_CU_FAIL


InterX2InFail_X2AP_LINK_FAIL


InterX2InFail_X2AP_SIG_FAIL


InterX2InFail_X2AP_SIG_TO

A call is released due to X2AP signaling timeout (not received) during the inter X2 handover execution.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36.423 E-UTRA and E-UTRAN; X2 Application Protocol (X2AP)


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LTE-SW1015, Frequency-priority-based HO INTRODUCTION General coverage-based inter-frequency handover would not be triggered as far as possible during serving cell quality is good to make for user to stay in serving cell. But in multi-carrier environment, different handover scheme regardless of serving cell quality should be needed according to operator’s usage purpose per carrier frequency. Suppose operator deploys small cells on the different frequency from macro cells in hot spot area for offloading macro traffic. This offloading can be possible by forcing handover of users closed to the small cells. For these requirements, Samsung supports Frequency priority based handover (FPbased HO, FPHO). FPHO is a forced handover based on pre-assigned perfrequency priority. eNB determines higher priority frequencies based on the perfrequency priority. Higher priority frequency means a frequency which priority is higher than serving frequency’s priority. FPHO makes that users can detect there are neighbouring cells of higher priority frequencies at any place within serving cell, and eNB performs FPHO when it decides that handover to a higher priority frequency can be possible from user’s report. Operator can configure per-frequency priority, and also can configure FPHO specific handover parameters per frequency for differentiating handover triggering criteria from coverage-based inter-frequency handover.

BENEFIT Operator can differentiate handover criteria according to frequency priority. Operator can steer or distribute their subscribers based on the usage purpose per frequency band, and then they can maximize frequency resource usages in multi-carrier environment.



Interface & Protocols RRC, S1, X2 eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Prerequisite Features oLTE-SW1003 (Intra-eNB Handover) oLTE-SW1004 (S1 Handover) oLTE-SW1005 (X2 Handover) oLTE-SW1007 (Inter-Frequency Handover) oLTE-SW1010 (Intra-LTE Redirection) oLTE-SW1016 (Forced Handover Control) oLTE-SW1401 (Handover between LTE-FDD and TD-LTE)

LIMITATION Frequency priority based handover cannot be possible if a user is selected for the following features:

SPID UEs based on LTE-SW2014 SPID (Subscriber Profile ID for RAT/Frequency Priority) based handover

MBMS interest UEs based FR40 of LTE-SV0513 MBMS service continuity Scell activated UEs, and Intra-eNB hand-in UEs based on LTE-SW1017 Interfrequency handover for CA

SYSTEM IMPACT Interdependencies between Features Interdependent Feature: Inter-Frequency Handover Frequency-priority based Handover feature enables inter-frequency handover toward higher priority frequency layers regardless of serving cell quality. In the cell edge, inter-frequency handover toward any priority frequency layers can be possible as well as the conventional inter-frequency handover.

FEATURE DESCRIPTION For FPHO, when call setup or hand-in of the UE which supports the higher priority frequencies, eNB orders inter-frequency measurement for the higher priority frequencies. Then the UE can perform inter-frequency measurement for the higher priority frequencies regardless of serving cell quality and it will report to eNB if handover event is occurred. When receiving UE’s measurement report for handover to the higher priority frequencies, eNB will directly trigger FPHO for the UE to move to the higher priority frequency.

Initial measurement configuration In case FPHO is enabled, initial measurement configuration is performed as following procedure for a UE when call setup, hand-in or change of QCI mobility group by E-RAB setup/modify/release. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1) eNB extracts the UE’s candidate carriers considering UE’s supported bands, serving cell’s configuration for intra-LTE and inter-RAT mobility based on operator’s policy. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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2) eNB adds UE measurement configuration for intra-frequency mobility: serving frequency with HO event(A3/A4/A5) for intra-frequency mobility. 3) eNB checks FPHO option and performs next step based on FPHO option. oIf FPHO option≠noUse, Go to step 4). oElse, Go to step 7). 4) eNB checks the possibility for FPHO based on UE capabilities. oIf there are higher priority frequencies in UE supported bands and UE supports inter-frequency measurement, that is, FGI#25 = 1, Go to step 5). oElse, Go to step 7). 5) eNB adds UE measurement configuration for FPHO: higher priority frequencies with HO event(A4/A5) per higher priority frequencies for FPHO and measurement gap if needed. In case of Hand-in UE, this step will be performed at handover completion. 5-1) eNB selects the configurable higher priority frequencies to be configured. 5-2) eNB configures reportConfig for HO event (A4/A5) per higher priority frequencies for FPHO. 5-3) eNB configures measGap if needed. 5-4) eNB configures s-Measure based on s-Measure usage option. 6) For FPHO capable UE,eNB adds UE measurement configuration for interfrequency mobility to All frequencies: Event A2 for inter-frequency mobility. 7) For FPHO incapable UE,eNB adds UE measurement configuration for interfrequency mobility: Event A2 for inter-frequency mobility. 8) eNB adds UE measurement configuration for inter-RAT mobility: Event A2 for inter-RAT mobility. 9) eNB sends RRC Connection Reconfiguration message to the UE, including UE measurement configuration of step 2), 5), 6) or 7). In case of Hand-in UE, UE measurement configuration of step 5) is not included. 10) In case of Hand-in UE and when receiving RRC Connection Reconfiguration Complete message from UE (at Handover completion), eNB starts Forced HO Restriction timer. Then when the Forced HO Restriction timer will be expired, eNB checks whether to need UE measurement configuration for FPHO. oIf needed, Go to step 5). oElse, this procedure ends. 11) eNB sends RRC Connection Reconfiguration message to the UE, including UE measurement configuration for FPHO: higher priority frequencies with HO event (A4/A5)per higher priority frequencies for FPHO and measurement gap if needed (Details are refer to the step 5)).


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FPHO triggering and FPHO procedure If FPHO specific MR is received from UE, eNB decides whether FPHO triggering and performs the following procedure.

1) eNB decides FPHO target cell according to the following condition: oThe best cell in measuredCells of the FPHO specific MR; and oHO to the best cell is allowed; and oThe best cell is not Forbidden TA based on the UE's Handover Restriction List. 2) eNB checks Available capacity threshold for FPHO for the target frequency. oIf Available capacity threshold for FPHO≠0, Go to step 3). oElse, Go to step 4). 3) eNB eNB checks the available capacity of FPHO target cell. oIf there is no available capacity of FPHO target cell, Go to step 4). oElse if there is available capacity of FPHO target cell >= Available capacity threshold for FPHO, Go to step 4). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oElse, Go to step 7). 4) eNB checks UE’s HO capability. oIf HO capable to the target frequency, Go to step 5). oElse, Go to step 6). 5) eNB triggers FPHO to target cell. 6) eNB performs MR based redirection to the frequency of FPHO specific MR. 7) eNB discards the FPHO specific MR.

Release of FPHO measurement configuration If FPHO measConfig release option = Use, eNB start Timer for release of FPHO measConfig at FPHO specific measurement configuration. Then when the timer will be expired, eNB releases FPHO specific measurement configuration.

Handling for FPHO specific MR collision When receiving FPHO specific MR during processing for previous MR for mobility, eNB checks the frequency priority of previous MR and FPHO specific MR. If the last FPHO specific MR’s frequency priority is higher than that of the previous MR, eNB performs FPHO based the last FPHO specific MR.

Discard the previous MR; and Cancel the HO if already HO triggered due to the previous MR. This action is not applied for following features' MR: MLB, eICIC, CA and PCC selection.



Basic EUTRA FA Configuration should be configured correctly by CHGEUTRA-FA. Activation Procedure To activate this feature, do the following:

Run CHG-FPHO-CTRL and set FPHO_SUPPORT to True.


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Run CHG-EUTRA-A4CNF [and CHG-EUTRA-A4CNFQ] and set ACTIVE_STATE of ci_A4PurposeInterFrequencyFPHO purpose to Active.

Run CHG-EUTRA-A5CNF [and CHG-EUTRA-A5CNFQ] and set ACTIVE_STATE of ci_A5PurposeInterFrequencyFPHO purpose to Active.

Run CHG-EUTRA-FPHOPRIOR and assign a priority at FP_HO_PRIORITY for each Frequency. If operator does not assign a priority, all Frequencies have the same priority and Frequency Priority Based Handover does not happen. Deactivation Procedure To deactivate this feature, do the following: Run CHG-FPHO-CTRL and set FPHO_SUPPORT to False.

Key Parameters This section describes the key parameters for activation/deactivation of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-FPHO-CTRL/RTRV-FPHO-CTRL Parameter

Description

FPHO_SUPPORT

It shows whether Frequency Priority Based Handover is supported. False(0): Frequency Priority Based Handover is not supported. True(1): Frequency Priority Based Handover is supported.


Description

ACTIVE_STATE


Parameter Descriptions of CHG-EUTRA-A4CNFQ/RTRV-EUTRA-A4CNFQ Parameter

Description

ACTIVE_STATE



390



Description

ACTIVE_STATE



Description

ACTIVE_STATE


Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-FPHO-CTRL/RTRV-FPHO-CTRL Parameter

Description

S_MEASURE_OPTION

It shows whether s-Measure is applied in case of the UE Measurement for Frequency Priority Based Handover (s-Measure is not applied in case of UE Measurement when s-Measure is set to 0.). False(0): s-Measure is not applied. True(1): s-Measure is applied.

MEAS_DURATION_OPTION

It shows whether Measurement Configuration for Frequency Priority Based Handover is maintained. False(0): In case FPHO is not triggered within the set time, Measurement Configuration for Frequency Priority Based Handover is released. True(1): Measurement Configuration for Frequency Priority Based Handover is maintained continuously.

Parameter Descriptions of CHG-EUTRA-FPHOPRIOR/RTRV-EUTRAFPHOPRIOR Parameter

Description

FP_HO_PRIORITY

Priority of each frequency to select the target frequency for Frequency Priority Based Handover. The frequency with a priority higher than the Serving Frequency is selected as the target frequency. In the range of the priority, 0 is the lowest and 7 is the highest priority.


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Description

CAPA_THRESHOLD

The threshold of Available Capability for each Target frequency to restrict Frequency Priority Based Handover. In case Available Capability of the Frequency Priority Based Handover Target Cell is lower than the threshold, Frequency Priority Based Handover to the cell is not performed. If it is set to 0, Frequency Priority Based Handover is performed regardless of Available Capability of the Target Cell.

HO_EVENT_TYPE

Select the Handover Event Type to trigger Frequency Priority Based Handover. ci_FpHoEventA4(0): Trigger inter-frequency handover by Event Type A4. ci_FpHoEventA5(1): Trigger inter-frequency handover by Event Type A5.


Description

A4_THRESHOLD_RSRP

This parameter is the RSRP threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment.

A4_THRESHOLD_RSRQ

This parameter is the RSRQ threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on the RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment.

HYSTERESIS

This parameter is the hysteresis value of Event A4 during ReportConfigEutra configuration. This information is used to determine the entering condition [(Measurement Result - Hysteresis) Threshold] and leaving condition [(Measurement Result + Hysteresis) Thresh]. The hysteresis uses the unit defined in the TS36.331 and its range is 0-30. The actual value is converted into hysteresis * 0.5 dB. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs.

TIME_TO_TRIGGER

This parameter is the timeToTrigger value for the Event A4. The timeToTrigger is the time which should be satisfied for the UE to trigger the measurement report. The event A4 occurs only when a specific threshold meet a threshold during the period of TIME_TO_TRIGGER and the TIME_TO_TRIGGER can be set to a value 0-5120 ms as defined in the TS.36.331. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs.

TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A4 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to


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Description rsrp/rsrq. An UE transmits Event A4 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A4_THRESHOLD_RSRP is used. If it is RSRQ, the A4_THRESHOLD_RSRQ is used. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: It indicates that RSRP is used for triggerQuantity. rsrq: It indicates that RSRQ is used for triggerQuantity. followA2event: It indicates that the value of TriggerQuantity corresponds with the value of A2 Event triggerQuantity. both: It indicates that RSRP and RSRQ are used for triggerQuantity.

REPORT_QUANTITY

This parameter is the information on quantity included in the measurement report for the Event A4. It can be specified to be the same as the trigger quantity, or to contain both RSRP and RSRQ value. This information is for setting whether to report only values equal to the triggerQuantity (RSRP or RSRQ), or all values (RSRP and RSRQ), when a device is reporting measurement results. This change will be applied to the UE from next RRC signaling procedure (for exmaple, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. sameAsTriggerQuantity: If it is set to sameAsTriggerQuantity, the UE transmits only the result corresponding to the TRIGGER_QUANTITY. both: A UE transmits both RSRP/RSRQ if the REPORT_QUANTITY is set to both for the measurement result when transmitting Event A4.

MAX_REPORT_CELL

This parameter is used to set up the maxReportCells of Event A4 during ReportConfigEutra configuration. This information is maximum number of neighbor cells that can be included in the measurement report for Event A4. When transmitting the measurement report for Event A4, a UE can add the measurement report of EUTRA neighbor cell as many as MAX_REPORT_CELL if there is the measurement result of EUTRA neighbor cell. This change will be applied to the UE from next RRC signaling procedure (for exmaple, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs.

REPORT_INTERVAL

This parameter is the interval of measurement reports for the Event A4. This information is for setting the Measurement Report transmission interval when a device is reporting measurement results. The REPORT_INTERVAL must transmit a measurement report at the interval of REPORT_INTERVAL as many times as specified in the REPORT_AMOUNT if it meets the event A4 condition. This applies only when the REPORT_AMOUNT is larger than 1. The REPORT_INTERVAL can be set to 120 ms-60 min.

REPORT_AMOUNT

This parameter is used to set up the reportAmount of Event A4 during ReportConfigEutra configuration. It is for setting the number of measurement reports (Event A4) for a device reporting measurement results. The REPORT_AMOUNT is the number of measurement report transmit when the Event A4 condition is met. If the REPORT_AMOUNT is larger than 1, the measurement report is transmitted as many times as REPORT_AMOUNT according to the interval specified in REPORT_INTERVAL. The REPORT_AMOUNT is set to 1-infinity according to the TS36.331. If it is set to infinity, a measurement report is transmitted at the interval of REPORT_INTERVAL until the A4 leaving condition is met. This change will be applied to the UE from next RRC signaling procedure (for example, attach or idle to active). To avoid overload, a new setting will not be updated to the current active UEs.

Parameter Descriptions of CHG-EUTRA-A4CNFQ/RTRV-EUTRA-A4CNFQ


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Description

A4_THRESHOLD_RSRP

This parameter is the RSRP threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment.

A4_THRESHOLD_RSRQ

This parameter is the RSRQ threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on the RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment.

HYSTERESIS


TIME_TO_TRIGGER


TRIGGER_QUANTITY


REPORT_QUANTITY

This parameter is the information on quantity included in the measurement report for the Event A4. It can be specified to be the same as the trigger quantity, or to contain both RSRP and RSRQ value. This information is for setting whether to report only values equal to the triggerQuantity (RSRP or


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Description RSRQ), or all values (RSRP and RSRQ), when a device is reporting measurement results. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. sameAsTriggerQuantity: If it is set to sameAsTriggerQuantity, the UE transmits only the result corresponding to the TRIGGER_QUANTITY. both: A UE transmits both RSRP/RSRQ if the REPORT_QUANTITY is set to both for the measurement result when transmitting Event A4.

MAX_REPORT_CELL

This parameter is used to set up the maxReportCells of Event A4 during ReportConfigEutra configuration. This information is maximum number of neighbor cells that can be included in the measurement report for Event A4. When transmitting the measurement report for Event A4, a UE can add the measurement report of EUTRA neighbor cell as many as MAX_REPORT_CELL if there is the measurement result of EUTRA neighbor cell. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs.

REPORT_INTERVAL


REPORT_AMOUNT



Description

A5_THRESHOLD1_RSRP

This parameter is the A5_Threshold1 value of Event A5 during ReportConfigEutra configuration. It range is 0-97. This value used when the TRIGGER_QUANTITY is set to RSRP.

A5_THRESHOLD2_RSRP

This parameter is the A5_Threshold2 value of Event A5 during ReportConfigEutra configuration, it is set to 0-97. This value used when the TRIGGER_QUANTITY is set to RSRP.

A5_THRESHOLD1_RSRQ

This parameter is the A5_Threshold1 value of Event A5 during ReportConfigEutra configuration, it is set to 0-34. This value is used when the TRIGGER_QUANTITY is set to RSRQ.

A5_THRESHOLD2_RSRQ


HYSTERESIS

This parameter is the hysteresis value of Event A5 during ReportConfigEutra configuration. This information is used to determine the entering condition


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Description [(Measurement Result - Hysteresis) Threshold] and leaving condition [(Measurement Result + Hysteresis) Thresh]. The hysteresis uses the unit defined in the TS36.331 and its range is 0-30. The actual value is converted into hysteresis * 0.5 dB. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs.

TIME_TO_TRIGGER


TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A5 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq. An UE transmits Event A5 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A5_THRESHOLD_RSRP is used. If it is RSRQ, the A5_THRESHOLD_RSRQ is used. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: It indicates that RSRP is used for triggerQuantity. rsrq: It indicates that RSRQ is used for triggerQuantity. both: It indicates that RSRP and RSRQ are used for triggerQuantity. followA2event: It indicates that the value of TriggerQuantity corresponds with the value of A2 Event triggerQuantity.

REPORT_QUANTITY

This parameter is the information on quantity included in the measurement report for the Event A5. It can be specified to be the same as the trigger quantity, or to contain both RSRP and RSRQ value. This information is for setting whether to report only values equal to the triggerQuantity (RSRP or RSRQ), or all values (RSRP and RSRQ), when a device is reporting measurement results. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. sameAsTriggerQuantity: If it is set to sameAsTriggerQuantity, the UE transmits only the result corresponding to the TRIGGER_QUANTITY. both: A UE transmits both RSRP/RSRQ if the REPORT_QUANTITY is set to both for the measurement result when transmitting Event A5.

MAX_REPORT_CELL


REPORT_INTERVAL


REPORT_AMOUNT

This parameter is used to set up the reportAmount of Event A5 during


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Description ReportConfigEutra configuration. It is for setting the number of measurement reports (Event A5) for a device reporting measurement results. The REPORT_AMOUNT is the number of measurement report transmit when the Event A5 condition is met. If the REPORT_AMOUNT is larger than 1, the measurement report is transmitted as many times as REPORT_AMOUNT according to the interval specified in REPORT_INTERVAL. The REPORT_AMOUNT is set to 1-infinity according to the TS36.331. If it is set to infinity, a measurement report is transmitted at the interval of REPORT_INTERVAL until the A5 leaving condition is met. This change will be applied to the UE from next RRC signaling procedure (for example, attach or idle to active). To avoid overload, a new setting will not be updated to the current active UEs.


Description

A5_THRESHOLD1_RSRP

This parameter is the A5_Threshold1 value of Event A5 during ReportConfigEutra configuration. It range is 0-97. This value used when the TRIGGER_QUANTITY is set to RSRP.

A5_THRESHOLD2_RSRP

This parameter is the A5_Threshold2 value of Event A5 during ReportConfigEutra configuration, it is set to 0-97. This value used when the TRIGGER_QUANTITY is set to RSRP.

A5_THRESHOLD1_RSRQ


A5_THRESHOLD2_RSRQ


HYSTERESIS


TIME_TO_TRIGGER


TRIGGER_QUANTITY

This parameter is used to set up the TriggerQuantity of Event A5 during ReportConfigEutra configuration. The TRIGGER_QUANTITY can be set to rsrp/rsrq. An UE transmits Event A5 when RSRP or RSRQ meets a specific threshold according to TRIGGER_QUANTITY. If the TRIGGER_QUANTITY is RSRP, the A5_THRESHOLD_RSRP is used. If it is RSRQ, the A5_THRESHOLD_RSRQ is used. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. rsrp: It indicates that RSRP is used for triggerQuantity. rsrq: It indicates that RSRQ is used for triggerQuantity. both: It indicates that RSRP and RSRQ are used for triggerQuantity.


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Description followA2event: It indicates that the value of TriggerQuantity corresponds with the value of A2 Event triggerQuantity.

REPORT_QUANTITY

This parameter is the information on quantity included in the measurement report for the Event A5. It can be specified to be the same as the trigger quantity, or to contain both RSRP and RSRQ value. This information is for setting whether to report only values equal to the triggerQuantity (RSRP or RSRQ), or all values (RSRP and RSRQ), when a device is reporting measurement results. This change will be applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. sameAsTriggerQuantity: If it is set to sameAsTriggerQuantity, the UE transmits only the result corresponding to the TRIGGER_QUANTITY. both: A UE transmits both RSRP/RSRQ if the REPORT_QUANTITY is set to both for the measurement result when transmitting Event A5.

MAX_REPORT_CELL


REPORT_INTERVAL


REPORT_AMOUNT



REFERENCE [1] 3GPP TS 36.300: 'Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2'. (10.1.2.1.2, 10.1.2.3.1) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[2] 3GPP TR 36.331: Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification (5.3.1, 5.3.5.8)


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LTE-SW1017, Inter-Frequency Handover for CA INTRODUCTION A certain type of CA-capable UE cannot support CA at the current serving cell since the UE doesn‟t have any corresponding band combination for CA which has the serving frequency as a PCell in the operator‟s LTE network. (For example, rel. 12 TDD-FDD CA UEs do not support a TDD PCell.) On the other hand, in the case that the current cell‟s CA function might be turned off according to the operator‟s policy, all CA-capable UEs connected to the cell cannot use CAcapability. In the cases mentioned above, if some UEs support another CA band combination available in another frequency of the operator‟s network, directing these CA-capable UEs to the corresponding frequencies helps them get higher data rates.

BENEFIT A CA-capable UE can have more chances of getting higher data rate.

DEPENDENCY Prerequisite Features: LTE-SW5500 (CA Call Control)

LIMITATION The operator must configure the target frequencies, each of which supports CA PCell. Otherwise, unnecessary inter-frequency HOs will occur.

SYSTEM IMPACT Coverage This feature uses the dedicated A4 event parameter setting. The threshold (that is, a4ThresholdRSRP/RSRQ) can affect the area where HOs triggered by this feature occur.

FEATURE DESCRIPTION The figure shows an example to which this feature can be applied. If the UE supports TDD-FDD CA with a FDD PCell and its data traffic is heavy, moving the UE to the FDD frequency f1 will help the UE get higher data rate. However, it is unnecessary to move a TDD-FDD CA UE with a light traffic to the FDD frequency.


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Figure below depicts the procedure for inter-frequency HO for CA.

The procedure for inter-frequency HO for CA is as follows:

1 When a UE is newly connected to a cell, eNB checks the UE‟s CA capability such as its supported band combinations and the corresponding maximum aggregated bandwidths.

2 If eNB cannot configure a SCell to the CA-capable UE, then eNB monitors the amount of the downlink data traffic for the UE. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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3 If the amount of the data buffer for the UE exceeds a configured threshold, then eNB makes a candidate frequency set for measurement based on both the UE‟s CA capability and the target frequency list configured by operator.

4 eNB configures A4 event measurement to the UE. Then, eNB starts the timer for the allowed measurement duration (MEAS_REL_TIMER_FOR_FORCED_HO).

5 If eNB receives an A4 measurement report before the timer expires, eNB makes a decision on inter-frequency HO for CA. eNB does not perform HO if the reported target cell corresponds to the latest frequency in the UE History Information in the case of a hand-in UE or the target cell in the same eNB does not support any supported band combination of the UE. Otherwise, eNB performs inter-frequency HO.

6 If eNB cannot receive any A4 measurement report until the timer expires, eNB removes the corresponding measurement configuration from the UE.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature Activation Procedure Run CHG-CACELL-INFO and set INTER_FREQ_HO_FOR_CA_ENABLE to 1. Deactivation Procedure Run CHG-CACELL-INFO and set INTER_FREQ_HO_FOR_CA_ENABLE to 0.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CACELL-INFO/RTRV-CACELL-INFO. Parameter

Description

INTER_FREQ_HO_FOR_CA_ENABLE

This parameter indicates whether to support Inter-Frequency Handover for CA. 0: This feature is Inactive. 1: This feature is Active.


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Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CACELL-INFO/RTRV-CACELL-INFO. Parameter

Description

DATA_TRAFFIC_THRESHOLD

This parameter is data traffic threshold for Inter Frequency HO for CA. It means number of packet in Tx Buffer.

Parameter Descriptions of CHG-EUTRA-A4CNF/RTRV-EUTRA-A4CNF. Parameter

Description

PURPOSE

This parameter is data traffic threshold for Inter Frequency HO for CA. It means number of packet in Tx Buffer. This parameter is the purpose of using Event A4. IntraLteHandover: handover is executed ANR_Specific:the ANR operation is executed CA: SCELL is configured Sendback: the Sendback operation is executed InterFrequencyLb: the Active Load Balancing operation is executed ArpHandover: Enable inter frequency handover function for UEs that have a specific ARP OnDemandHandover: Enable the forced handover triggering by operator InterFrequencySPID: inter-frequency handover is executed for specific SPID with handover mobility option. InterFrequencyFPHO: For Frequency Priority Based Handover. InterFrequencyForCa: inter-frequency handover for non-CA UE to CA available Cell.

ACTIVE_STATE


A4_THRESHOLD_RSRP

This parameter is the RSRP threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intraeNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment. [Related Specifications] 3GPP TS 36.331

A4_THRESHOLD_RSRQ

This parameter is the RSRQ threshold used for the Event A4 that occurs when a neighbor becomes better than the threshold. The serving cell performs intra-eNB HO and inter-frequency HO if the frequency is configured to use the Event A4 triggering. The UE could measure either the Reference


403


Description Signal Received Power (RSRP) or the Reference Signal Received Quality (RSRQ) and TRIGGER_QUANTITY indicates it will operate based on the RSRP or RSRQ. This change will be applied to the UE from the next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. The higher the parameter is, the later the HO is performed and it can impact HO success rate, The lower the parameter is, the earlier the HO is performed and it can cause ping pong. This value needs to be optimized up to site environment. [Related Specifications] 3GPP TS 36.331

TRIGGER_QUANTITY



REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification [3] 3GPP 36.423: E-UTRAN; X2 application protocol (X2AP) [4] 3GPP 36.413: E-UTRAN; S1 application protocol (S1AP) [5] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [6] Feature Detail Description (LTE-SW5500) CA Call Control, Samsung Electronics


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LTE-SW1201, Idle Mobility to UTRAN INTRODUCTION This feature allows to support UE‟s idle mobility to UTRAN. For this, eNB broadcasts relevant cell reselection information in SIB6 message so that the UE performs cell reselection towards UTRAN when needed.

BENEFIT Operator can provide idle mobility to its subscribers to UTRAN. Users in idle state can move to UTRAN.

DEPENDENCY Related Radio Technology: E-UTRAN (LTE), UTRAN (3G)

LIMITATION None


FEATURE DESCRIPTION The eNB supports the UE's idle mobility through its SIB broadcasting. In the idle mode, the UE receives the SIB broadcast by the cell it has camped onto, and performs inter-RAT cell reselection to UTRAN based on the cell reselection parameter contained in the SIBs. The following SIBs are used to perform the functionality:

SIB1 provides information that is required in evaluating if a UE is allowed to access a cell. UE uses this for PLMN selection and cell selection. SIB1 also defines the scheduling of other system information. UE acquires other SIBs of the cell using this information.

SIB3 provides the common information required for intra-frequency, interfrequency and/or inter-RAT cell reselection. SIB3 also conveys the specific information for intra-frequency cell reselection.

SIB6 provides information about UTRA frequencies and parameters for cell reselection. (NodeBs located under or near LTE coverage broadcast LTE frequency information in SIB19.) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Cell Reselection Triggering and Measurement The inter-RAT cell reselection procedures are triggered when one of the following conditions is met:

1 The UE has E-UTRA frequencies or UTRA frequencies with a reselection priority higher than the reselection priority of the current E-UTRA frequency. In this case, the UE performs inter-RAT cell reselection procedures. The UE shall search every layer of higher priority at least every T higher_priority_search = (60 * Nlayers) seconds, where Nlayers is the total number of configured higher priority E-UTRA and UTRA carrier frequencies.(3GPP TS 36.133 Section 4.2.2)

2 The service cell does not fulfil Srxlev > S_NON_INTRA_SEARCH_P and Squal > S_NON_INTRA_SEARCH_Q. In this case, the UE performs inter-RAT cell reselection procedures for an E-UTRA inter-frequency or an UTRA frequency with an equal or lower reselection priority than the reselection priority of the current E-UTRA frequency. The priority of each frequency is broadcast in SIB3 (E-UTRA frequency) and SIB6 (UTRA frequency). Since RSRQ can vary even in the center of the serving cell from -3 dB to -10 dB depending on traffic load from the serving cell, devices will test Srxlev only. UE triggers the measurement of UTRA frequency when the RSRP signal strength from LTE serving cell decreases below the calculated threshold. Table below outlines the parameters that trigger cell reselection procedures. Parameter Name

Description

Srxlev

Cell selection RX level value (in dB) measured by UE

Squal

Cell selection quality value (in dB) measured by UE

S_INTRA_SEARCH

This specifies the Srxlev threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-8 device. (SIB3)

S_INTRA_SEARCH_P

This specifies the Srxlev threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-9 device. (SIB3)

S_INTRA_SEARCH_Q

This specifies the Squal threshold (in dB) for intra-frequency measurements. This parameter is used by Rel-9 device. (SIB3)

S_NON_INTRA_SEARCH

This specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-8 device. (SIB3)


This specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-9 device. (SIB3)


This specifies the Squal threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. This parameter is used by Rel-9 device. (SIB3)

Q_RX_LEV_MIN

This specifies the minimum required Rx level in the cell in dBm This parameter (SIB3)

Q_QUAL_MIN_REL9

This specifies the minimum required quality level in the cell in dB. This parameter is used by Rel-9 device. (SIB3)


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Cell Reselection Criteria from LTE to 3G UE performs the inter-RAT cell reselection procedures according to the following cell reselection criteria.

Cell reselection to a cell on a higher priority UTRA frequency than the serving frequency shall be performed if: oIf THRESH_SERVING_LOW_QREL9 is provided in SIB3, The cell of UTRA frequency fulfils Squal > THRESH_XHIGH_QREL9(SIB6) during a time interval T_RESELECTION(SIB6); and More than one second has elapsed since the UE camped on the current serving cell. oOtherwise, The cell of UTRA frequency fulfils Srxlev > THRESH_XHIGH(SIB6) during a time interval T_RESELECTION(SIB6); and More than one second has elapsed since the UE camped on the current serving cell.

Cell reselection to a cell on a lower priority UTRA frequency than the serving frequency shall be performed if: oIf THRESH_SERVING_LOW_QREL9 is provided in SIB3, The serving cell fulfils Squal < THRESH_SERVING_LOW_QREL9(SIB3) and a cell of UTRA frequency fulfils Squal > THRESH_XLOW_QREL9(SIB6) during a time interval T_RESELECTION(SIB6); and More than one second has elapsed since the UE camped on the current serving cell. oOtherwise, The serving cell fulfils Srxlev < THRESH_SERVING_LOW(SIB3) and a cell of UTRA frequency fulfils Srxlev > THRESH_XLOW(SIB6) during a time interval T_RESELECTION(SIB6); and More than one second has elapsed since the UE camped on the current serving cell. Srxlev and Squal for UTRAN cell are defined as follows: Srxlev = Qrxlevmeas - Q_RX_LEV_MIN(SIB6) - Pcompensation Squal = Qqualmeas - Q_QUAL_MIN(SIB6) where Pcompensation is derived as max(UE_TXPWR_MAX_RACH-P_MAX_UTRA, 0) (dB) according to 3GPP TS 25.304. UE_TXPWR_MAX_RACH is the maximum TX power level when accessing the cell on RACH (dBm). It is defined as 21 dBm in 3GPP TS 25.101. Figure below depicts UTRAN cell reselection criteria from LTE to 3G assuming that the priority of UTRA frequency is lower than E-UTRA frequency.


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The following UTRAN cell selection criteria should be also satisfied to obtain normal service: UTRAN cell selection criteria: Srxlev>0 AND Squal>0 Where, Srxlev = Qrxlevmeas - Q_RX_LEV_MIN (SIB6) - Pcompensation Squal = Qqualmeas - Q_QUAL_MIN (SIB6) Table below outlines each parameter for UTRA frequency cell reselection criteria. Parameter Name

Description

Srxlev

Cell selection RX level value (dB)

Squal

Cell selection quality value (dB)

Qrxlevmeas

Measured cell RX level value.

Qqualmeas

Measured cell quality value.

Pcompensation

max(UE_TXPWR_MAX_RACH-P_MAX_UTRA, 0) (dB)

UE_TXPWR_MAX_RACH

Maximum TX power level when accessing the cell on RACH (dBm). (3GPP TS25.101)

P_MAX_UTRA

Maximum allowed transmission power on the (uplink) carrier frequency (dBm) (SIB6)

Q_QUAL_MIN

Minimum required quality level in the cell (dB) (SIB6)

Q_RX_LEV_MIN


T_RESELECTION

Cell reselection timer (sec) for UTRAN cell reselection (SIB6)

THRESH_XHIGH

Srxlev threshold (dB) used by the UE when reselecting towards a higher priority UTRA frequency than the current serving frequency (SIB6)

THRESH_XHIGH_QREL9

Squal threshold (dB) used by the UE when reselecting towards a higher priority UTRA frequency than the current serving frequency (SIB6)

THRESH_XLOW

Srxlev threshold (dB) used by the UE when reselecting towards a lower priority UTRA frequency than the current serving frequency (SIB6)

THRESH_XLOW_QREL9

Squal threshold (dB) used by the UE when reselecting towards a lower priority UTRA frequency than the current serving frequency (SIB6)


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Chapter 4 Mobility Control Parameter Name

Description

THRESH_SERVING_LOW

This specifies the Srxlev threshold (dB) used by the UE on the serving cell when reselecting towards a lower priority inter-RAT frequency (SIB3)

THRESH_SERVING_LOW_QREL9

This specifies the Squal threshold (dB) used by the UE on the serving cell when reselecting towards a lower priority inter-RAT frequency (SIB3)

Cell reselection from 3G to LTE UE in idle mode may be connected to either LTE or 3G network depending on the radio condition. UE shall select primarily LTE frequency when the UE ends a CSFB call or when the UE comes back into LTE coverage in the presence of acceptable LTE signal. Cell reselection from UTRAN to LTE is performed by UE, based on the system information provided by UTRAN. The UE in UTRAN shall monitor the broadcast channel from the UTRAN serving cell during idle mode to retrieve SIB19 from UTRAN for preparation of cell reselection to E-UTRAN. The SIB19 E-UTRA Info List can provide up to eight different E-UTRA frequencies and priority information entries, indexing from 0 to 7. After cell reselection procedures to E-UTRAN is completed, UE performs a Tracking Area update in E-UTRAN. In SLR 6.0, the maximum number of configurable UTRA carriers has been changed upto 8 carriers


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature Activation Procedure The function of Idle Mobility to UTRAN is to perform cell reselection on UTRA frequency by UE in the idle mode. It can be activated and controlled by SystemInformationBlockType 6. (SIB6) when configuring UTRA FA priority and thresholds by using CHG-UTRA-FA. Deactivation Procedure This feature does not need to be deactivated.


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Key Parameters This section describes the key parameters for activation, and configuration of the feature. Activation/Configuration Parameters To activate or configure the feature, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-UTRA-FA/CHG-UTRA-FA Parameter

Description

priority

This parameter is the priority information of a UTRAN carrier. This information is used by the UE during idle reselection and broadcasted to the UE through SIBs. [Related Specifications] 3GPP TS 36.331

THRESH_XHIGH

This parameter is the threshold value used by the UE when reselecting the frequency with priority higher than the currently camped frequency. [Related Specifications] 3GPP TS 36.331

THRESH_XLOW

This parameter is the threshold value used when reselecting the low-priority frequency from the high-priority frequency. [Related Specifications] 3GPP TS 36.331

Parameter Descriptions of RTRV-EUTRA-FA/CHG-EUTRA-FA for EUTRA FA Information Parameter

Description

CELL_NUM

The cell number to be changed.

FA_INDEX

EUTRA frequency index. Up to 8 FAs can be assigned per cell.

STATUS

Whether the EUTRA FA is valid.

EARFCN_UL

Uplink E-UTRA Absolute Radio Frequency Channel Number.

EARFCN_DL

Downlink E-UTRA Absolute Radio Frequency Channel Number.

PRIORITY

Priority of EUTRA FA.

Q_RX_LEV_MIN

The minimum RX level required in a cell in dBm units. Actual value of threshold is the value * 2 (dBm).

P_MAX_USAGE

Whether to use pMax.

P_MAX

The maximum TX power level in the UE.

T_RESELECTION

Reselection timer value.

SF_USAGE

Whether to use scaling factors.

T_RESELECTION_SF_ME DIUM

The medium timer value of the reselection scaling factors. 0: ci_oDot25 (0.25) 1: ci_oDot5 (0.5) 2: ci_oDot75 (0.75) 3: ci_1Dot0 (1.0)

T_RESELECTION_SF_HIG H

The high timer value of the reselection scaling factors. 0: ci_oDot25 (0.25) 1: ci_oDot5 (0.5) 2: ci_oDot75 (0.75) 3: ci_1Dot0 (1.0)


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Description

S_INTRA_SEARCH_USAG E

Whether to use sIntraSearch.

S_INTRA_SEARCH

The threshold for intra-frequency measurement. Actual value of threshold is the value * 2 (dB).

S_NON_INTRA_SEARCH_ USAGE

Whether to use sNonIntraSearch.

S_NON_INTRA_SEARCH

The threshold for inter-RAT and intra-frequency measurement. Actual value of threshold is the value * 2 (dB).

THRESH_SERVING_LOW

The low threshold for serving frequency during reselection evaluation. Actual value of threshold is the value * 2 (dB).

MESA_BANDWIDTH_USA GE

Whether to use measurementBandwidth.

MEASUREMENT_BANDWI DTH

The maximum measurement bandwidth allowed for carrier frequency. 0: ci_mbw6 1: ci_mbw15 2: ci_mbw25 3: ci_mbw50 4: ci_mbw75 5: ci_mbw100

PRESENCE_ANT_PORT1

Whether Antenna Port1 exists. (SIB 3) False: Not Exist True: Exist

NEIGH_CELL_CONFIG

The neighboring cell settings. (TS36.331 section 6.3.6)

OFFSET_FREQ

Frequency offset value applied to offsetFreq in RRC Connection Reconfiguration. 0: ci_dB_24 1: ci_dB_22 2: ci_dB_20 3: ci_dB_18 4: ci_dB_16 5: ci_dB_14 6: ci_dB_12 7: ci_dB_10 8: ci_dB_8 9: ci_dB_6 10: ci_dB_5 11: ci_dB_4 12: ci_dB_3 13: ci_dB_2 14: ci_dB_1 15: ci_dB0 16: ci_dB1 17: ci_dB2 18: ci_dB3 19: ci_dB4 20: ci_dB5 21: ci_dB6 22: ci_dB8 23: ci_dB10


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Description 24: ci_dB12 25: ci_dB14 26: ci_dB16 27: ci_dB18 28: ci_dB20 29: ci_dB22 30: ci_dB24

S_INTRA_SEARCH_REL9 _USAGE

Whether to use the sIntraSearch for Rel-9.

S_INTRA_SEARCH_P

The threshold P for an intra-frequency measurement in Rel-9.

S_INTRA_SEARCH_Q

The threshold Q for an intra-frequency measurement in Rel-9.

S_NON_INTRA_SEARCH_ REL9_USAGE

Whether to use sNonIntraSearch for Rel-9.

S_NON_INTRA_SEARCH_ P

The threshold P for inter-RAT and an intra-frequency measurement. Actual value of threshold is the value * 2 (dB).

S_NON_INTRA_SEARCH_ Q

The threshold Q for inter-RAT and an intra-frequency measurement.

Q_QUAL_MIN_REL9_USA GE

Whether to use the qQualMin for Rel-9.

Q_QUAL_MIN_REL9

qQualMin value for Rel-9.

THRESH_SERVING_LOW _QREL9_USAGE

Whether to use the threshServingLowQ for Rel-9.

THRESH_SERVING_LOW _QREL9

threshServingLowQ value for Rel-9.

THRESH_XHIGH_QREL9

The threshold used in the UE to reselect a frequency whose priority is higher than the current camped frequency in Rel-9.

THRESH_XLOW_QREL9

The threshold used to reselect low-priority frequency from high-priority frequency in Rel-9.

Parameter Descriptions of RTRV-UTRA-CAR/CHG-UTRA-CAR for UTRA Carrier Parameter

Description

CELL_NUM


FA_INDEX

UTRA frequency index. Up to 6 FAs can be assigned per cell.

STATUS

Whether the UTRA FA information is valid.

DUPLEX_TYPE

The duplex mode information on a cell. Enter either FDD or TDD.

UARFCN_DL

Downlink UTRA Absolute Radio Frequency Channel Number.

RESEL_PRIORITY_USAGE

Whether cell reselection priority of UTRA FA is used.

PRIORITY

Priority information on the UTRA FA.

THRESH_XHIGH

The threshold used to reselect UTRA frequency whose priority is higher than the current camped frequency.

THRESH_XLOW

The threshold used to reselect UTRA frequency whose priority is lower than the current camped frequency.

Q_RX_LEV_MIN

The minimum RX level required in a cell in dBm units. Actual value of threshold is the value * 2 + 1 (dBm).

P_MAX_UTRA

The maximum RF output power in the UE.


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Description

Q_QUAL_MIN

The minimum quality level required in UTRA FDD cells.

THRESH_XHIGH_QREL9

The threshold used to reselect UTRA frequency whose priority is higher than the current camped frequency in Rel-9.

THRESH_XLOW_QREL9

The threshold used to reselect UTRA frequency whose priority is lower than the current camped frequency in Rel-9.

Parameter Descriptions of RTRV-UTRA-RESEL/CHG-UTRA-RESEL for UTRA Reselection Parameter

Description

CELL_NUM


T_RESELECTION

UTRAN FA Reselection timer value. The duration is in seconds.

SF_USAGE

Whether to use the scaling factors related to UTRAN FA reselection. CI_no_use: Scaling factor is not used. CI_use: Scaling factor is used.

T_RESELECTION_SF_ME DIUM

The medium timer value of the scaling factors related to UTRAN FA reselection. ci_oDot25: 0.25 is used for the medium timer. ci_oDot5: 0.5 is used for the medium timer. ci_oDot75: 0.75 is used for the medium timer. ci_1Dot0: 1.0 is used for the medium timer.

T_RESELECTION_SF_HIG H

The high timer value of the scaling factors related to UTRAN FA reselection. ci_oDot25: 0.25 is used for the high timer. ci_oDot5: 0.5 is used for the high timer. ci_oDot75: 0.75 is used for the high timer. ci_1Dot0: 1.0 is used for the high timer.


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36.304 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode


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LTE-SW1207, CSFB to UTRAN with Redirection without SI INTRODUCTION CS fallback is the function to provide LTE users a voice service prior to the introduction of the Voice over LTE (VoLTE), it switches the UE over to the legacy UTRAN CS domain to provide mobile originated/mobile terminated call. This feature allows UE to switch toward the UTRAN in accordance with the Redirection without SI procedure. When the S1 message including the CSFB indicator is received from the MME, the eNB clears the UE‟s RRC connection and specifies the carrier frequency of the UTRAN to which the UE is to switch over (redirection without SI). The UE switches over to the target carrier frequency of the UTRAN specified by the eNB and initiates the voice call sending/receiving procedure.

BENEFIT Operator can provide CS service to its subscribers by using legacy CS network (UTRAN).

Users can do a CS call while staying in E-UTRAN, by transition to legacy CS network (UTRAN).


Related Radio Technology E-UTRAN (LTE), UTRAN (3G)

Interface & Protocols SGs interface is required.

LIMITATION None


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SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. This feature affects external interfaces as follows: Air interface The RRC Message RRC CONNECTION RELEASE includes a CSFB target frequency.

FEATURE DESCRIPTION With the default LTE data network connection in operation, a mobile terminating (incoming) CS voice call triggers paging via LTE network to the UE. This paging message initiates CSFB, as the device sends an NAS EXTENDED SERVICE REQUEST to the network to transition to 3G network. Once transitioned, the legacy call setup procedures are followed to setup the CS call. A mobile originating (outgoing) call follows the same transition from LTE (PS) to 3G (CS), except for the paging step. In 3G networks, PS data sessions can also be established simultaneously for data services. After the voice call ends and the UE returns to idle state, the device should perform cell reselection procedures to reselect LTE cell. If the UE has still PS session after the voice call ends, then the UE remains in 3G cell. 3G network coexists with LTE network residing between the mobile customer‟s User Equipment (UE) and the core network. MME serves users while in LTE access network. In a 3G network, SGSN serves users when utilizing data services and MSC when utilizing voice services. To support CSFB signalling, the MME connects to the MSC with SGs interface. The SGs interface is used for the mobility management and paging procedures between EPS and CS domain. And it is also used for the delivery of both mobile originating and mobile terminating SMS. Figure below depicts the architecture and interfaces for CSFB.


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In general, UE informs MME about the type of attach required during the attach procedure. In case 'Attach Type' in the Attach request message is 'Combined EPS/IMSI Attach', combined CS and PS updates are executed. For Combined EPS/IMSI Attach there is a requirement to use SGs interface, between MME and MSC. To enable „CSFB to UTRAN based on Redirection without SI‟ feature, the parameter „CSFB_BLIND_SUPPORT‟ should be set as „BLIND_SUPPORT‟ using „CHG-INTWO-OPT‟ command. This parameter is used for the selection of the interworking option per cell. And „RIM_ENABLE‟ parameter should be set as „FALSE‟ using „CHG-HO-OPT‟. This parameter decides to disable the RIM procedure per eNB. Figure below depicts redirection based CSFB to UTRAN procedures when UE is in idle mode.


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1) UE, in idle state, originates a voice call or receives a mobile terminated voice call. 2~5) Since UE is in idle state, it starts RRC connection establishment procedures with eNB in order to make a SRB connection. UE sends NAS Extended Service Request message to MME, which is included in RRC Connection Setup Complete message. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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6) MME sends eNB S1-AP Initial Context Setup Request message that includes CSFB indicator. 7) eNB processes the AS security activation. 8) eNB transmits S1-AP Initial Context Setup Response message to MME. At this step, eNB does not setup a DRB connection because UE is going to redirect to UTRAN. 9) eNB sends RRC Connection Release message to UE. The message includes UTRA carrier frequency to which UE will be redirected. 10~14) eNB transmits UE Context Release Request message to MME, in order to release S1 bearer connection between eNB and S-GW. S5 bearer between S-GW and P-GW is retained. If the UE sends Routing Area Update message to SGSN, then the SGSN will trigger RAU procedure with old MME. In this case, SGSN will make a bearer connection between itself and P-GW and MME will remove the S5 bearer connection. Usually, CSFB UE sends Routing Area Update message because it changes the Routing Area, but, depending on UE implementation it may not trigger RAU procedure because it will go back to LTE network as soon as it ends the CSFB call. 15~17) UE connects to UTRAN and sets up a CS session. UE performs UTRAN location update procedures. At this step, UE is not expected to set up a PS session because the UE was in idle state. Figure below depicts redirection based CSFB to UTRAN procedures when UE is in connected mode.


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1) UE, in connected state, originates a voice call or receives a mobile terminated voice call. 2~3) UE sends NAS Extended Service Request message to MME. eNB and UE already have both SRB and DRB because the UE is in connected mode. 4) MME sends eNB S1-AP UE Context Modification Request message that includes CSFB indicator. 5) eNB transmits S1-AP UE Context Modification Response message to MME. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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6) eNB sends RRC Connection Release message to UE. The message includes UTRA carrier frequency to which UE will be redirected. At this step, eNB releases both SRB and DRB. 7~11) eNB transmits UE Context Release Request message to MME, in order to release S1 bearer connection between eNB and S-GW. S5 bearer between S-GW and P-GW is retained but the state is changed to idle mode. If the UE sets up a PS bearer in UTRAN, SGSN will make a bearer connection between SGSN and PGW (GGSN) for seamless IP mobility and MME will remove the S5 bearer connection. 12~14) UE connects to UTRAN and sets up a CS session. UE performs UTRAN location update procedures. At this step, UE is expected to set up a PS session as well because there was an ongoing active bearer. The PS session can be continued in UTRAN with the same IP address. According to the characteristics of the deployed site, the number of UTRA frequencies is configurable. Up to eight different UTRA frequencies can be assigned per cell. And the purpose of each UTRA frequency can be configurable based on supported service as follows:

CS_ONLY(1): for CSFB (Redirection without SI, Redirection with SI, HO), SRVCC

PS_ONLY(2): for PS mobility (Redirection without SI, Redirection with SI, HO) BOTH(0): for all cases In SLR 6.0, this feature has been enhanced that the CSFB mobility method and its target RAT/carrier selection based on the UE state are configurable. According to this configuration, operator can manage the active UE's CSFB operation and idle UE's CSFB operation differently.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure To activate this feature, the operator should configure the UTRAN Frequency Information by using CHG-UTRA-FA command, set either 'IS_HOALLOWED' to False, or 'PS_HO_SUPPORT' to False by using CHG-NBR-UTRAN command. Deactivation Procedure To deactivate this feature, the operator should set 'IS_HOALLOWED' to true, and 'PS_HO_SUPPORT' to true by using CHG-NBR-UTRAN command. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-UTRA-FA/RTRV-UTRA-FA Parameter

Description

STATUS

This parameter indicates whether to use the UTRAN carrier information. N_EQUIP: Does not use the UTRAN carrier information. EQUIP: Uses the UTRAN carrier information.

DUPLEX_TYPE

This parameter is the duplex mode information of a UTRAN carrier. FDD: Frequency Division Duplex. TDD: Time Division Duplex.

UARFCN_UL

This parameter sets the Uplink Absolute Radio Frequency Channel Number(ARFCN) value for the UTRA Frequency. It executes Data Rule Check (DRC) to ensure that the same Uplink ARFCN value based on the EQUIP state is not entered.

UARFCN_DL

This parameter sets the Downlink Absolute Radio Frequency Channel Number(ARFCN) value for the UTRA Frequency. It executes Data Rule Check (DRC) to ensure that the same Downlink ARFCN value based on the EQUIP state is not entered.

Parameter Descriptions of CHG-NBR-UTRAN/RTRV-NBR-UTRAN Parameter

Description

IS_HOALLOWED

This parameter indicates whether to perform handover to UTRAN neighboring cell. False: Handover is not allowed. True: Handover is allowed.

PS_HO_SUPPORT

This parameter indicates whether the neighbor UTRAN cell supports PS-HO or not. False: PS-HO is not supported. True: PS-HO is supported.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-INTWO-OPT/RTRV-INTWO-OPT Parameter

Description

CSFB_UESTATE

This parameter indicates UE state based CSFB availability.

CSFB_IN_IDLE

This parameter indicates the operator choice for target RAT type when UE is in Idle Mode.

CSFB_IN_ACTIVE

This parameter indicates the operator choice for target RAT type when UE is in Active Mode.

CSFB_TO3_GFAFOR_IDLE

This parameter indicates the operator choice for target FA type when UE is in


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Description Idle Mode.

CSFB_TO3_GFAFOR_ACTI VE

This parameter indicates the operator choice for target FA type when UE is in Active Mode.

Parameter Descriptions of CHG-INTWO-OPTQCI/RTRV-INTWO-OPTQCI Parameter

Description

CSFB_UESTATE

This parameter indicates UE state based CSFB availability.

CSFB_IN_IDLE

This parameter indicates the operator choice for target RAT type when UE is in Idle Mode.

CSFB_IN_ACTIVE

This parameter indicates the operator choice for target RAT type when UE is in Active Mode.

CSFB_TO3_GFAFOR_IDLE

This parameter indicates the operator choice for target FA type when UE is in Idle Mode.

CSFB_TO3_GFAFOR_ACTI VE

This parameter indicates the operator choice for target FA type when UE is in Active Mode.


Type Name

Type Description

CSFB_REDIR_UTRAN_OUT

CSFBRedirUtranAtt

CSFB with Redirection to inter-RAT UTRAN attempt count

CSFBRedirUtranPrepSucc

CSFB with Redirection to inter-RAT UTRAN preparation success count.

CSFBRedirUtranSucc

CSFB with Redirection to inter-RAT UTRAN execution success count.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS36.413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP) [4] 3GPP TS23.272 Circuit Switched Fallback in Evolved Packet System; Stage 2


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LTE-SW1301, Idle Mobility to GERAN INTRODUCTION To support from E-UTRAN to GERAN cell reselection, the eNB broadcasts the System Information Block type 7 (SIB7). The UE monitors the E-UTRAN BCCH during idle mode to retrieve the SIB7 for the preparation of cell reselection to GERAN. It measures the neighboring GERAN cells based on the criteria and performs cell reselection to GERAN. The parameters for cell reselection to GERAN broadcasted in SIB7 are as follows:

GERAN carrier frequency group list. Cell reselection priority per carrier frequency group. GERAN neighboring cell information. Thresholds for cell reselection criteria. Cell reselection timer. Parameters for speed dependent cell reselection.

BENEFIT You can provide idle mobility to subscribers to GERAN. Users in idle state can move to GERAN.

DEPENDENCY AND LIMITATION Dependency GERAN supported device, EPC, and GERAN must support this feature

FEATURE DESCRIPTION The eNB supports the UE idle mobility through SIB broadcasting. In the idle mode, the UE receives the SIB broadcast by the cell it has camped on. The UE performs the inter-RAT cell reselection to GERAN based on the cell reselection parameter included in the SIBs. The following SIBs are used to perform the functionality:

SIB1 provides information that is required in evaluating if a UE is allowed to access a cell. The UE uses this for PLMN selection and cell selection. The SIB1 also defines the scheduling of other system information. The UE acquires other SIBs of the cell using this information. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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SIB3 provides the common information required for the intra-frequency, interfrequency and/or inter-RAT cell reselection. SIB3 also conveys the specific information for intra-frequency cell reselection.

SIB7 provides information on GERAN frequencies and parameters for cell reselection. GERAN cell reselection parameters broadcasted via SIB7 are as follows:

GERAN carrier frequencies per GERAN carrier frequency group. A set of GERAN carrier frequencies can be provided in three ways: explicitListOfARFCNs, equallySpacedARFCNs, and variableBitMapOfARFCNs.

Cell reselection priority per GERAN carrier frequency group. Cell reselection thresholds per GERAN carrier frequency group. Cell reselection timer for GERAN cell reselection. Cell reselection timer for speed dependant GERAN cell reselection For fast moving UE, speed dependent GERAN cell reselection scaling factors are applied. If the number of reselections during the period TCRmax is greater than the NCR_H, high mobility is detected. If the number exceeds NCR_M and not NCR_H, then medium mobility is detected. In the high/medium mobility states, Qhyst and TreselectionRAT are multiplied by the speed dependent scaling factors: Qhyst and Treselection. The reselection to GERAN is performed if (Srxlev_GSM Qrxlevmin in SIB7) > (Srxlev of LTE cell - Qrxlevmin in SIB3 + Qhyst in SIB3)

Cell Reselection Triggering and Measurement The inter-RAT cell reselection procedures are triggered when one of the following conditions is met:

The UE has E-UTRA or GERAN frequencies with a reselection priority higher than the reselection priority of the current E-UTRA frequency. In this case, the UE performs inter-RAT cell reselection procedures. The UE searches every layer of higher priority at least every T_higher_priority_search = (60 * N_layers) seconds. Where N_layers is the total number of configured higher priority E-UTRA carrier frequencies and is additionally increased by one if one more group of GERAN frequencies is configured as a higher priority. (3GPP TS 36.133 Section 4.2.2)

The service cell does not fulfil S_rxlev > S_NON_INTRA_SEARCH_P and S_qual > S_NON_INTRA_SEARCH_Q. In this case, the UE performs interRAT cell reselection procedures for an E-UTRA inter-frequency or a GERAN frequency with an equal or lower reselection priority than the reselection priority of the current E-UTRA frequency. The priority of each frequency is broadcasted in the SIB3 (E-UTRA frequency) and SIB7 (GERAN frequency). As RSRQ can vary even in the center of the serving cell from -3 dB to -10 dB depending on traffic load from the serving cell, UEs test S_rxlev only.


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The UE triggers the measurement of GERAN frequency when the RSRP signal strength from LTE serving cell decreases below the calculated threshold.

Cell Reselection Criteria from LTE to 2G Considering that the priority of GERAN frequency is lower than E-UTRAN, cell reselection to a cell on a lower priority GERAN frequency than the serving frequency is performed according to GERAN cell reselection criteria, shown in the figure below.

The UE reselects the GERAN cell when RSRP signal strength from LTE serving cell decreases to less than the threshold calculated and the signal strength of GERAN target cell increases to more than the calculated threshold (3GPP TS 36.304 Section 5.2.4.5).

Cell reselection from 2G to LTE The UE in idle mode can be connected to either LTE or GERAN network depending on the radio condition. It selects primary LTE frequency when it ends a CSFB call or when the UE comes back into the LTE coverage in the presence of acceptable LTE signal. The UE performs the cell reselection from GERAN to LTE based on the system information provided by GERAN. It, in GERAN, monitors the broadcast channel from the GERAN serving cell during idle mode to retrieve the System Information 2Quarter message for preparation of cell reselection to E-UTRAN. After cell reselection to E-UTRAN is completed, the UE performs a tracking area update in E-UTRAN.

SYSTEM OPERATION How to Activate Run the command CHG-SIB-INF to configure the SIB7_PERIOD. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Run the command CHG-GERAN-FA to configure the GERAN frequency information.

Key Parameters CHG-SIB-INF/RTRV-SIB-INF Parameter

Description

SIB7_PERIOD

This parameter is the transmission period for the system information block type 7 of the cell in the eNB. SIB7 contains information for IRAT cell reselection to GERAN. ms80: 80 ms. ms160: 160 ms. …. ms5120: 5120 ms. not_used: SIB7 is not transmitted.

CHG-GERAN-FA/RTRV-GERAN-FA Parameter

Description

STATUS

This parameter indicates whether the GERAN FA object is valid. N_EQUIP: Invalid. EQUIP: Valid.

FOLLOWING_ARFCNS

The followingARFCNs is the choice option to select the remaining ARFCN values except startingARFCN. explicitList: used for explicitListOfARFCNs. Set geranArfcn0 to geranArfcn31. equallySpaced: used for equallySpacedARFCNs. Set geranArfcn0, arfcnSpacing and numberOfFollowingARFCNs. variableBitMap: used for variableBitMapOfARFCNs. Set geranArfcn0 and variableBitMapOfARFCNs.

GERAN_ARFCN0

This parameter is the ARFCN of the GERAN FA object (start ARFCN).

GERAN_ARFCN1~GERAN_A This parameter is the ARFCN of the GERAN FA object. RFCN31 ARFCN_SPACING

If followingARFCNs is set to equallySpaced, arfcnSpacing becomes Space, d, between a set of equally spaced ARFCN values.

NUMBER_OF_FOLLOWING_ If followingARFCNs is set to equallySpaced, numberOfFollowingARFCNs ARFCNS becomes The number, n, of the remaining equally spaced ARFCN values in the set. The complete set of (n + 1) ARFCN values is defined as: {s, ((s + d) mod 1024), ((s + 2*d) mod 1024) ... ((s + n*d) mod 1024)}. s is startingARFCN (geranArfcn0). VARIABLE_BIT_MAP_OF_A RFCNS [16]

If followingARFCNs is set to variableBitMap, variableBitMapOfARFCNs becomes Bitmap field representing the remaining ARFCN values in the set. The leading bit of the first octet in the bitmap corresponds to the ARFCN = ((s + 1) mod 1024), the next bit to the ARFCN = ((s + 2) mod 1024), and so on. If the bitmap consist of N octets, the trailing bit of octet N corresponds to ARFCN = ((s + 8*N) mod 1024). The complete set of ARFCN values consists of ARFCN = s and the ARFCN values, where the corresponding bit in the bitmap is set to 1. s is startingARFCN (geranArfcn0).

Counters and KPIs There are no related counters or KPIs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification [3] 3GPP TS36.304 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode [4] 3GPP TS23.401 Technical Specification Group Services and System Aspects; GPRS enhancements for E-UTRAN access


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LTE-SW1309, CSFB to GERAN with Redirection without SI INTRODUCTION CS fallback is the function to provide LTE users a voice service prior to the introduction of the Voice over LTE (VoLTE), it switches the UE over to the legacy GERAN CS domain to provide mobile originated/mobile terminated call. The CSFB to GERAN with Redirection without SI function switches the UE to the GERAN in accordance with the Redirection without SI procedure. When the S1 message including the CSFB indicator is received from the MME, the eNB clears the UE‟s RRC connection and specifies the carrier frequency of the GERAN to which the UE is to switch over (redirection without SI). The UE switches over to the target carrier frequency of the GERAN specified by the eNB and initiates the voice call sending/receiving procedure.

BENEFIT Operator can provide CS service to its subscribers by using legacy CS network (GERAN)

Users can do a CS call while staying in E-UTRAN, by transition to legacy CS network (GERAN)

DEPENDENCY GERAN supported device, EPC and GERAN shall support this feature.

LIMITATION None


FEATURE DESCRIPTION Regardless of a UE movement, CSFB is triggered when there is mobile originating or mobile terminating call.


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To support CSFB service, 2G network coexists with LTE network where in. MME serves users while in LTE access network, and SGSN serves users while in 2G access network. In a 2G network SGSN serves users when utilizing data services and MSC (Mobile Switching Center) when utilizing voice services. To support CS Fallback signaling, the MME connects to the MSC with SGs interface. The SGs interface is used for the mobility management and paging procedures between EPS and CS domain. And it is also used for the delivery of both mobile originating and mobile terminating SMS. Following figure shows the architecture and interfaces for CSFB.

In general, UE informs MME about the type of attach required during the attach procedure. In case 'Attach Type' in the Attach request message is 'Combined EPS/IMSI Attach', combined CS and PS updates are executed. For Combined EPS/IMSI Attach there is a requirement to use SGs interface, between MME and MSC. Below is the procedure for performing the CSFB with Redirection to GERAN without SI when UE is in active.


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1) The UE initiates the CSFB procedure. If the UE is in idle state, the UE uses the RRC connection establishment procedure to switch over to the connected state. Above figure shows the case when UE is in Active state. 2) The UE transmits the NAS EXTENDED SERVICE REQEUST which is embedded in RRC UL Information Transfer message. 3) eNB relays NAS message to the MME using S1AP Uplink NAS Transport message 4) The MME transmits the S1AP UE Initial Context Setup Request message in which the CSFB indicator is included to the eNB., The eNB processes the AS security activation and the default bearer setup procedure. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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5) The eNB transmits the S1AP Initial Context Setup Response message to the MME. 6) The eNB includes the GERAN carrier frequency to which the UE is to switch over and transmits the RRC Connection Release to the UE. (Optionally, the eNB may request measurement of GERAN before step 6) 7~11) The eNB transmits the UE Context Release Request to the MME. The MME further processes the S1 release procedure with the eNB. 13) The UE switches over to the GERAN Carrier frequency given in the RRC Connection Release designated by the eNB and connects to the GERAN. It initiates the GERAN location registration procedure. 14) If the GERAN cannot provide simultaneous CS and PS service, the UE request the GERAN to suspend the PS service. 15~16) The SGSN processes bearers suspension procedure in accordance with the UE‟s request. The MME suspends the S-GW and PS bearers in accordance with the request from the SGSN. 17) After then, the UE performs the CS call setup and continues providing the CS service. Below figure depicts the call for CSFB when UE is in Idle state.


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UE should support GERAN radio technology and CSFB service. There should be GERAN neighbour network. Activation Procedure To activate this feature, do the following:

Run CHG-GERAN-FA to configure GERAN Frequency Information. Run CHG-GERAN-INTWO to configure 'Normal type' inter-networking procedure based on UE measurement and 'Blind type' inter-networking procedure without UE measurement.

Run CHG-INTWO-OPT/CHG-INTWO-OPTQCI to enable LTE system to select target RAT base on UE‟s current connection state for CSFB operation. Deactivation Procedure This feature does not need to be deactivated. CSFB to GERAN network can be disabled by removing GERAN system from neighbour relationship of the LTE system‟s.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There is no special Activation/Deactivation Parameters except some parameters required to configure. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-GERAN-FA/RTRV-GERAN-FA. Parameter

Description

STATUS

This parameter indicates whether the GERAN FA object is valid. N_EQUIP: Invalid. EQUIP: Valid.

FOLLOWING_ARFCNS

The followingARFCNs is the choice option to select the remaining ARFCN values except startingARFCN. explicitList: used for explicitListOfARFCNs. set geranArfcn0~geranArfcn31. equallySpaced: used for equallySpacedARFCNs. set geranArfcn0, arfcnSpacing and numberOfFollowingARFCNs. variableBitMap: used for variableBitMapOfARFCNs. set geranArfcn0 and variableBitMapOfARFCNs.


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Description

GERAN_ARFCN0

This parameter is the Absolute Radio Frequency Channel Number(ARFCN) of the GERAN FA object. (Start ARFCN)

GERAN_ARFCN1~GERAN_ ARFCN31

This parameter is the Absolute Radio Frequency Channel Number(ARFCN) of the GERAN FA object.

ARFCN_SPACING

If followingARFCNs is set to equallySpaced, arfcnSpacing becomes Space, d, between a set of equally spaced ARFCN values.

NUMBER_OF_FOLLOWING _ARFCNS

If followingARFCNs is set to equallySpaced, numberOfFollowingARFCNs becomes The number, n, of the remaining equally spaced ARFCN values in the set. The complete set of (n + 1) ARFCN values is defined as: {s, ((s + d) mod 1024), ((s + 2*d) mod 1024) ... ((s + n*d) mod 1024)}. s is startingARFCN (geranArfcn0).

VARIABLE_BIT_MAP_OF_A RFCNS

If followingARFCNs is set to variableBitMap,variableBitMapOfARFCNs becomes Bitmap field representing the remaining ARFCN values in the set. The leading bit of the first octet in the bitmap corresponds to the ARFCN = ((s + 1) mod 1024), the next bit to the ARFCN = ((s + 2) mod 1024), and so on. If the bitmap consist of N octets, the trailing bit of octet N corresponds to ARFCN = ((s + 8*N) mod 1024). The complete set of ARFCN values consists of ARFCN = s and the ARFCN values, where the corresponding bit in the bitmap is set to 1. s is startingARFCN (geranArfcn0).

Parameter Descriptions of CHG-GERAN-INTWO/RTRV-GERAN-INTWO. Parameter

Description

NORMAL_PRIORITY0

This parameter indicates the first priority in the normal type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

NORMAL_PRIORITY1

This parameter indicates the second priority in the normal type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

NORMAL_PRIORITY2

This parameter indicates the third priority in the normal type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

NORMAL_PRIORITY3

This parameter indicates the fourth priority in the normal type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

BLIND_PRIORITY0

This parameter indicates the first priority of blind type GERAN interworking procedure. ccoWithNACC: CCO with NACC.


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Description ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

BLIND_PRIORITY1

This parameter indicates the second priority in the blind type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

BLIND_PRIORITY2

This parameter indicates the third priority in the blind type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

BLIND_PRIORITY3

This parameter indicates the fourth priority in the blind type GERAN interworking procedure. ccoWithNACC: CCO with NACC. ccoWithoutNACC: CCO without NACC. enhancedRedirection: Enhanced Redirection with SI. geranRedirecdtion: Redirection without SI.

Parameter Descriptions of CHG-INTWO-OPT/CHG-INTWO-OPTQCI/RTRVINTWO-OPT/RTRV-INTWO-OPTQCI Parameter

Description

CSFB_UESTATE

Indicates UE state based CSFB availability.

CSFB_IN_IDLE

Indicates operator choice for target RAT type when UE is in Idle Mode.

CSFB_IN_ACTIVE

Indicates operator choice for target RAT type when UE is in Active Mode.

Counters and KPIs Table below outlines the main counters associated with this feature. KPIs will depend on an agreement with Operator. Family Display Name

Type Name

Type Description

CSFB GERAN Redirection

CSFBGeranRedirAtt

Count of CSFB with Inter RAT GERAN Redirection attempts.

CSFBGeranRedirPrepSucc

Count of CSFB with Inter RAT GERAN Redirection preparation successes.

CSFBGeranRedirSucc

Count of CSFB with Inter RAT GERAN Redirection execution successes.


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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification [3] 3GPP TS36.413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP) [4] 3GPP TS23.272 Circuit Switched Fallback in Evolved Packet System; Stage 2


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LTE-SW2011, Service based Intra-LTE Handover INTRODUCTION The UE can use a variety of services such as Voice over LTE, Web, or FTP in the LTE network. Because each service has different characteristics, it is necessary to use a different handover policy for each service. For example, in case of VoLTE in a multi-carrier environment, it is necessary to enable the UE to handover to the carrier with good coverage. Services with a different QoS use a different QCI. For handover control for each service, the eNB applies the handover policy set for each QCI. The service based intra-LTE handover function can be used in the multi-carrier environment. The eNB uses this function only to the UE that supports multi-carrier.

BENEFIT Using a handover policy set for each QCI, a different handover policy can be applied for a different service.

The mobility quality of VoLTE can be improved.

DEPENDENCY AND LIMITATION Dependency This feature can be enabled in the multi-carrier environment. Limitation Up to five mobility profiles are allowed.

QCI five is determined according to the default mobility profile (mobility profile 0).

The UE must support multi-carrier.

FEATURE DESCRIPTION Sets the parameters required for service based intra-LTE handover. The provisioning/parameter settings for service based intra-LTE. Appropriate mobility profile is allocated to each QCI. Table below shows an example of the mobility profile allocation according to QCI. The mobility profile 0 is the default configuration, which is allocated to the QCI that does not belong to mobility profiles 1 to 4. For QCI five, mobility profile 0 is allocated instead of 1 to 4. Table below is an example of the mobility profile allocation for each QCI. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 4 Mobility Control Mobility Profile #

Mobility Profile 0

Mobility Profile 1

Mobility Profile 2

Mobility Profile 3

Mobility Profile 4

QCIs allocated to each mobility group

Default configuration (Default value per QCI)

QCI 1

QCI 2, 3, 4

QCI 7, 8, 9

No allocated QCI

Mobility control related items are set for each mobility profile, as shown below.

Preferred target carrier frequencies for E-UTRAN (FDD or TDD). Handover triggering event. Measurement configuration. Blind redirection option. The UE can have multiple QCIs belonging to different mobility profiles. In such cases, the mobility profile of a UE is determined by the mobility profile associated with highest priority QCI of the UE. If the highest priority QCI is associated with default mobility profile, then the service based handover is disabled for the UE and existing handover is applied. Table below is an example of priority allocation per QCI. QCI #

0

1

2

3

4

5

6

7

8

9

Priority

9

2

4

3

5

1

6

7

8

9

The mobility profile for a UE is determined based on the QCI of a bearer that is used by the UE. Therefore, a different handover policy can be used per QCI. Figure below is an example of service based intra-LTE handover.

For example, the UE A and UE B have QCI 1 and 9 respectively and mobility profile per QCI is set as shown in below table. The mobility profile 1 is allocated to UE A and 2 is allocated to UE B. In this case, if a preferred carrier is set to Carrier A for mobility profile 1 and B for mobility profile 2, the UE A handovers to Carrier A and UE B handovers to Carrier B, as shown in figure above. Table below is an example of mobility profile allocation per QCI that is set in the UE. UE

A

B

QCI

1

9


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Chapter 4 Mobility Control UE

A

B

Mobility Profile

Mobility Profile 1

Mobility Profile 2

SYSTEM OPERATION How to Activate Run the command CHG-QCI-VAL to configure QCI mobility group ID to each QCI value. If multiple bearers with different QCIs are configured for the same UE, then the QCI mobility group ID with highest priority QCI is selected. The QCI mobility group specific handover parameters can be configured by running the commands: RTRV/CHG EUTRA-FAQCI, RTRV/CHG-EUTRA-A1CNFQ, RTRV/CHGEUTRA-A2CNFQ, RTRV/CHG-EUTRA-A3CNFQ, RTRV/CHG-EUTRAA4CNFQ, AND RTRV/CHG-EUTRA-A5CNFQ. If specific QCI mobility group is going to use Event A3 to handover to the specific FA, then run the command:

CHG-EUTRA-FAQCI to set handover type to be A3. CHG-EUTRA-A3CNFQ to set the active status of the corresponding cell, handover purpose, QCI group index, and FA index.

Key Parameters RTRV-QCI-VAL/CHG-QCI-VAL (QCI mobility group configuration) Parameter

Description

QCI


STATUS


PRIORITY

This parameter is the priority of the QoS Class Identifier (QCI). The range is 1 to 16, and 1 means the highest priority.

QCI_MOBILITY_GROUP_ID

This attribute defines the QCI Mobility Group ID of the QCI.

RTRV-EUTRA-FAQCI/CHG-EUTRA-FAQCI Parameter

Description

CELL_NUM


FA_INDEX

EUTRA frequency index. Up to 8 FAs can be assigned per cell.

QCI_GROUP_INDEX

QCI Group index.

STATUS

Whether the EUTRA FA is valid. N_EQUIP: Invalid. EQUIP: Valid.


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Description

OFFSET_FREQ

Frequency offset value applied to offsetFreq in RRC Connection Reconfiguration.

HANDOVER_TYPE

Handover Type per Carrier ci_HoEventA3 ci_HoEventA4 ci_HoEventA5

RTRV-EUTRA-A1CNFQ/CHG-EUTRA-A1CNFQ Parameter

Description

CELL_NUM


QCI_GROUP_INDEX

QCI Group index.

ACTIVE_STATE

This parameter indicates whether event A1 is enabled/disabled per target frequency. Inactive: Event A1 is not used. Active: Event A1 is used.


Description

CELL_NUM


PURPOSE

This parameter is the purpose of using the Event A2 per cell. It is used to activate the measurement gap as default. LteHo: Used for gap activate. LteBlind: Used for blind handover. IRatHo: Used for IRAT handover. IRatBlind: Used for IRAT blind handover. Ca: Used for carrier aggregation. CaPeriodicMr: Used for add smart carrier aggregation periodic measure configuration. Srvcc: Used for single radio voice call continuity. Mdt: Used for minimization of drive tests. Spare_2: Reserved.

ACTIVE_STATE

This parameter indicates whether event A2 is enabled/disabled per target frequency. Inactive: Event A2 is not used. Active: Event A2 is used. If handover of the target frequency is not needed in the site, this is inactive. This change is applied to the UE from next RRC signaling procedure (for example, Attach or Idle to Active). To avoid overload, new setting is not updated to the current active UEs.

RTRV-EUTRA-A3CNFQ/CHG-EUTRA-A3CNFQ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

CELL_NUM


PURPOSE

This parameter is the purpose of using Event A3 event. IntraLteHandover: Performs handover. ReportStrongestCells: Performs the ANR operation. IntraFrequencyLb Spare_2: Reserved. Not used at this moment.

QCI_GROUP_INDEX

QCI Group index.

FA_INDEX

The FA_INDEX is a parameter corresponding to the FA_INDEX of EUTRA-FA. The configuration conditions of A3 event (A3_OFFSET, TRIGGER_QUANTIY, and so on.) can be set differently per FA. To configure A3 event for a specific FA, the status of EUTRA-FA (FA_INDEX#n) must be EQUIP and the ACTIVE_STATE of EUTRA-A3CNF (FA_INDEX#n) must be Active.

ACTIVE_STATE

This parameter is the purpose of using Event A3 event. If this is set to Inactive, the A3 event is not configured.


Description

CELL_NUM


PURPOSE

This parameter is the purpose of using Event A4 event. A4PurposeUntraLteHandover: handover is executed. A4PurposeANR_Specific: The ANR operation is executed. A4PurposeCA: SCELL is configured A4PurposeUnloading: The unloading operation is executed. A4PurposeSpare_2: It is not used at this moment because it is reserved for future use.

QCI_GROUP_INDEX

QCI group index.

FA_INDEX

The FA_INDEX is a parameter corresponding to the FA_INDEX of EUTRA-FA. The configuration conditions of A4 event (A4_THRESHOLD_RSRP, TRIGGER_QUANTIY, and so on.) can be set differently per FA. To configure A4 event for a specific FA, the status of EUTRA-FA (FA_INDEX#n) must be EQUIP and the ACTIVE_STATE of EUTRA-A4CNF (FA_INDEX#n) must be Active. The ANR_Specific/CA/Unloading is only used to configure FA_INDEX #0 and other values are ignored.

ACTIVE_STATE



Description

CELL_NUM



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Description

PURPOSE

This parameter is the purpose of using Event A5 event. IntraLteHandover: Intra-LTE handover. Spare_1: Reserved. Spare_2: Reserved.

QCI_GROUP_INDEX

QCI Group index.

FA_INDEX

The FA_INDEX is a parameter corresponding to the FA_INDEX of EUTRA-FA. The configuration conditions of A5 event (A5_THRESHOLD_RSRP1, TRIGGER_QUANTIY, and so on.) can be set differently per FA. To configure A5 event for a specific FA, the status of EUTRA-FA (FA_INDEX#n) must be EQUIP and the ACTIVE_STATE of EUTRA-A5CNF (FA_INDEX#n) must be Active.

ACTIVE_STATE



Type Name

Type Description

-

IntraEnbAtt

Intra-eNB handover attempt count

IntraEnbPrepSucc

Intra-eNB handover preparation success count.

IntraEnbSucc

Intra-eNB handover execution success count.

IntraEnbPrepFail_CP_CC_TO

Intra-eNB handover preparation fails due to due to call control timeout in the protocol blocks (MAC, RLC, PDCP, and GTP).

IntraEnbPrepFail_CP_CC_FAI Intra-eNB handover preparation fails due to L reset notification (eNB failure or block restart) from ECMB or by the ECCB block. IntraEnbPrepFail_UP_MAC_F AIL

Intra-eNB handover preparation fails due to the failure in the MAC block.

IntraEnbPrepFail_UP_RLC_FA Intra-eNB handover preparation fails due to the IL failure in the RLC block IntraEnbPrepFail_RRC_SIG_F Intra-eNB handover preparation fails due to AIL receiving RRC signaling. IntraEnbPrepFail_CP_BH_CA C_FAIL

Intra-eNB handover preparation fails due to backhaul QoS based CAC.

IntraEnbPrepFail_CP_CAPA_ CAC_FAIL

Intra-eNB handover preparation fails due to Capacity based CAC.

IntraEnbPrepFail_CP_QOS_C AC_FAIL

Intra-eNB handover preparation fails due to Air QoS based CAC.

IntraEnbPrepFail_S1AP_CU_F Intra-eNB handover preparation fails due to the AIL S1AP specification cause. IntraEnbPrepFail_S1AP_LINK _FAIL

Intra-eNB handover preparation fails due to the S1 SCTP link failure

IntraEnbPrepFail_S1AP_SIG_ FAIL

Intra-eNB handover preparation fails due to receiving S1AP signaling

IntraEnbFail_CP_CC_TO

Intra-eNB handover fails due to call control timeout in the protocol blocks (MAC, RLC, PDCP, and GTP).

IntraEnbFail_CP_CC_FAIL

Intra-eNB handover fails due to reset notification (eNB failure or block restart) from ECMB or by the ECCB block.


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Type Name

Type Description

IntraEnbFail_UP_GTP_FAIL

Intra-eNB handover fails due to the failure in the GTP block.

IntraEnbFail_UP_MAC_FAIL

Intra-eNB handover fails due to the failure in the MAC block.

IntraEnbFail_UP_RLC_FAIL

Intra-eNB handover fails due to the failure in the RLC block.

IntraEnbFail_RRC_HC_TO

Intra-eNB handover fails due to handover preparation timeout (not received handover command).

IntraEnbFail_RRC_SIG_FAIL

Intra-eNB handover fails due to receiving RRC signaling.

IntraEnbFail_S1AP_CU_FAIL

Intra-eNB handover fails due to the S1AP specification cause.

IntraEnbFail_S1AP_LINK_FAI L

Intra-eNB handover fails due to the S1 SCTP link failure.

IntraEnbFail_S1AP_SIG_FAIL

Intra-eNB handover fails due to receiving S1AP signaling.

IntraHOTime

Time taken from transmitting the RRCConnectionReconfiguration message to the UE until after receiving the RRCConnectionReconfiguration complete message from the UE.

IntraHOTimeMax

Average maximum intra-handover interrupt time.

IntraHOTimeTot

Sum of intra-handover interrupt time.

IntraHOTimeCnt

Count of IntraHOTime collected.

REFERENCE N/A


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LTE-SW2014, SPID based Dedicated Priority INTRODUCTION The eNB supports dedicated signaling with inter-frequency/RAT cell reselection or handover priorities based on Subscriber Profile ID (SPID). Two types of SPIDs are supported:

Specification based. Operator specific.

BENEFIT You can control the idle mode camping RAT and carriers of a UE based on absolute priorities determined by the subscription information.

You can control service frequency of a UE based on the absolute priorities determined by the subscription information.

DEPENDENCY AND LIMITATION Dependency Operator specific values required. Limitation The reference values, SPID= 1 to 128, 254, 255 and 256 can be supported.

SPID dedicated priority is supported for only LTE, UTRAN, or GERAN frequencies.

FEATURE DESCRIPTION The SPID information is received from the MME (Initial Context Setup Request/UE Context Modification/Downlink NAS Transport) or other eNBs (Handover Setup Request). The eNB supports the inter-frequency handover or reselection priority based on the dedicated priority each SPID.

SPID-based Inter-frequency Handover When the eNB receives UE SPID, it checks whether the SPID is set by the operator. If the SPID is set, the eNB performs the inter-frequency handover for the highest prioritized frequency in the dedicated priority list.


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Related Operation When the eNB receives UE SPID, it selects frequencies for which the UseFlag is set to use.

The eNB performs measurement (A4 and A5) using the RRCConnectionReconfiguration procedure for the highest prioritized frequencies among selected frequencies.

The eNB sets the measurement gap, which leads to search for inter-frequency cell. When the eNB receives the measurement report by Event A4 (neighbor cell signal strength only) or A5, it performs inter-frequency handover toward the searched frequency.

SPID-based Inter-RAT Handover When the eNB receives UE SPID, it checks whether the SPID is set by the operator. If the SPID is set and the highest prioritized frequency is inter-RAT frequency, the eNB performs the inter-RAT handover to the selected frequency. Related Operation When the eNB receives UE SPID, it selects frequencies for which the UseFlag is set to use.

If the highest prioritized frequency is inter-RAT frequency, the eNB performs measurement (B1 and B2) using the RRCConnectionReconfiguration procedure on the highest prioritized inter-RAT frequency.

The eNB sets the measurement gap, which leads to search for inter-frequency cell. When the eNB receives the measurement report by B1 or B2, it performs the inter-frequency handover toward the searched frequency.

If the frequencies of multiple RATs have the same highest priority, one target RAT is selected according to the fixed order of LTE > UTRAN > GERAN.

SPID-based Reselection Priority During the RRC Connection Release occurrence, the SPID setup of corresponding UE is verified by the eNB. If the setup is completed, the corresponding dedicated priority list is transferred to UE by the eNB. Related Operation When configuring the RRC Connection Release to MS, verify if the SPID (1 to 128, 254, 255, and 256) of MS is set.

Allow configuration of IdleModeMobilityControlInfo only for the SPID set to MS with UseFlag on. At this point, only include RAT supported according to UE radio capability of MS to exclude non-supported RAT information.

If UseFlag is off for the SPID set for UE, configure IdleModeMobilityControlInfo according to the Idle mode Load Balancing feature.

Transmit the configured RRC Connection Release message to MS. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Specification SPID Range 1 to 128: Operator-specific SPID values.

129 to 256: Reference values. Reference SPID Values Table below cites the eNB local configuration in idle and connected modes for SPID = 256. Configuration parameter

Value

Meaning

E-UTRAN carriers priority

high

The selection priorities for idle and connected mode of all E-UTRAN carriers are higher than the priorities for all UTRAN and GERAN carriers.

UTRAN carriers priority

medium

The selection priorities for idle and connected mode of all UTRAN carriers are lower than the priorities for all E-UTRAN carriers and higher than the priorities for all GERAN carriers.

GERAN carriers priority

low

The selection priorities for idle and connected mode of all GERAN carriers are lower than the priorities for all E-UTRAN and UTRAN carriers.

Table below cites the eNB local configuration in idle and connected modes for SPID = 255. Configuration parameter

Value

Meaning


high

The selection priorities for idle and connected mode of all UTRAN carriers are higher than the priorities for all GERAN and E-UTRAN carriers.


medium

The selection priorities for idle and connected mode of all GERAN carriers are lower than the priorities for all UTRAN carriers and higher than the priorities for all E-UTRAN carriers.


low

The selection priorities for idle and connected mode of all E-UTRAN carriers are lower than the priorities for all UTRAN and GERAN carriers.

Table below cites the eNB local configuration in idle and connected modes for SPID = 254. Configuration parameter

Value

Meaning


high

The selection priorities for idle and connected mode of all GERAN carriers are higher than the priorities for all UTRAN and E-UTRAN carriers.


medium

The selection priorities for idle and connected mode of all UTRAN carriers are lower than the priorities for all GERAN carriers and higher than the priorities for all E-UTRAN carriers.


low

The selection priorities for idle and connected


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Chapter 4 Mobility Control Configuration parameter

Value

Meaning mode of all E-UTRAN carriers are lower than the priorities for all GERAN and UTRAN carriers.

SYSTEM OPERATION How to Activate Run the command RTRV/CHG-EUTRA-PRIOR to set the dedicated priority of the FA to the specific SPID for EUTRAN FA.

Run the command RTRV/CHG-UTRA-PRIOR to set the dedicated priority of the FA to the specific SPID for UTRAN FA.

Run the command RTRV/CHG-GERAN-PRIOR to set the dedicated priority of the FA to the specific SPID for GERAN FA.

If you want to make a UE with specific SPID to intra-LTE handover to FA with the highest dedicate priority using A4 or A5 measurement event:

aRun the command CHG-EUTRA-PRIOR to set SPID_MOBILITY_OPTION of the specific Cell/PLMN/FA/SPID with the highest dedicatedPriority value to 'handoverOnly' or 'both'

bRun the command CHG-EUTRA-PRIOR to set SPID_MEASURE_OPTION of the corresponding Cell/PLMN/FA/SPID to 'hoEventA4' or 'hoEventA5'

cRun the command CHG-EUTRA-A4CNF or CHG-EUTRA-A5CNF with index A4purposeInterFrequencySPID or A5purposeInterFrequencySPID to set ACTIVE_STATE of the A4 or A5 event for the corresponding cell/FA to be active (if service based handover feature is applied, EUTRAA4CNFQ or EUTRA-A5CNFQ with the relevant QCI mobility group ID has to be considered also.

If you want to make a UE with specific SPID to inter-RAT handover to FA with the highest dedicate priority using B1 or B2 measurement event:

aRun the command CHG-UTRA-PRIOR or CHG-GERAN-PRIOR to set SPID_MOBILITY_OPTION of the specific cell/PLMN/FA/SPID with the highest dedicatedPriority value to handoverOnly or both.

bRun the command CHG-UTRA-PRIOR or CHG-GERAN-PRIOR to set SPID_MEASURE_OPTION_INTER_RAT of the corresponding cell/PLMN/FA/SPID to hoEventB1 or hoEventB2.

cRun the command CHG-UTRA-B1CNF/CHG-UTRA-B2CNF or CHGGERAN-B1CNF/CHG-GERAN-B2CNF to set activeState of the B1 or B2 event for the corresponding cell/FA to be active (if the service specific handover feature is applied, UTRA-B1CNFQ/UTRA-B2CNFQ or GERAN-B1CNFQ/GERAN-B2CNFQ with the relevant QCI mobility group ID has to be considered also.).


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Key Parameters RTRV-EUTRA-PRIOR/CHG-EUTRA-PRIOR Parameter

Description

CELL_NUM


PLMN_ID

PLMN index. It is mapping to mcc/mnc configured in plmnIdx of PLDEnbPlmnInfo.

FA_ID

This parameter is the Evolved Universal Terrestrial Radio Access (EUTRA) frequency index. This parameter enters the FA value that each cell supports and it is mapped to the FA_INDEX parameter value in the RTRV-EUTRA-FA command.

SPID_INDEX

This parameter is the SPID. This parameter is the index used to refer to the registration information of a subscriber.

SPID

This parameter is the SPID for Radio Access Terminal (RAT)/frequency priority value. The range of an entered value is 1 to 128 and a value between 129 and 253 cannot be entered.

USED_FLAG

This parameter shows whether the dedicated priority is used. no_use: Dedicated priority is not used. use: Dedicated priority is used.

DEDICATED_PRIORITY

This parameter is the dedicated priority value. Enter a dedicated priority value according to the FA_INDEX and SPID.

SPID_MOBILITY_OPTION

Define additional operations based on the mobility setting of the parameter for SPID of the UE. reselectionOnly (0): When UE is released, send the dedicated priority per FA for SPID that the UE currently possesses among the FAs supported in UE Radio Capability through IdleModeMobilityControlInfo. However, A4 or A5 based inter-frequency handover based on SPID shall not be performed. handoverOnly (1): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE radio capability, attach A4 or A5 event to induce inter-frequency handover. In this case, idleModeMobilityControlInfo to be transmitted when the UE is released based on the Idle Mode Load Balancing feature. both (2): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE radio Capability, attach A4 or A5 event to induce inter-frequency handover. In addition, when the UE is released, the dedicated priority per FA configured in SPID that the UE currently possesses among the FAs that can be supported in UE Radio Capability shall be transmitted through IdleModeMobilityControlInfo.

SPID_MEASURE_OPTION

If spidMobilityOption is handoverOnly or both, designate measurement event type to trigger inter-frequency handover. spidHoEventA4(0):measurement event type for inter-frequency handover triggering is EventA4. spidHoEventA5(1):measurement event type for inter-frequency handover triggering is EventA5.

RTRV-UTRA-PRIOR/CHG-UTRA-PRIOR


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Description

CELL_NUM

This parameter specifies the cell number to retrieve the periodic report config information used for interoperating with the UTRAN.

PLMN_INDEX


FA_ID

This parameter is the Universal Terrestrial Radio Access (UTRA) frequency index. The operator can enter a FA value each cell supports and maximum 6 FAs can be entered. This parameter is mapped to the FA_INDEX parameter value included in the RTRV-UTRA-FA command.

SPID_INDEX

This parameter is the Subscriber Profile ID (SPID) index. This parameter is the index used to refer to the registration information of a subscriber.

SPID

SPID for RAT/frequency priority. It cannot be set from 129 to 253.

USED_FLAG

Whether to use dedicatedPriority. CI_no_use: dedicatedPriority is not used. CI_use: dedicatedPriority is used.

DEDICATED_PRIORITY

Dedicated Priority Value for Frequency according SPID. According to 3GPP TS36.300, if SPID is 255, dedicated priority is set to 7.


Define additional operations based on the mobility setting of the parameter for SPID of the UE. reselectionOnly (0): When UE is released, send the dedicated priority per FA for SPID that the UE currently possesses among the FAs supported in UE Radio Capability through IdleModeMobilityControlInfo. However, B1 or B2 based inter-RAT handover to UTRAN based on SPID shall not be performed. handoverOnly (1): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE Radio Capability, attach B1 or B2 event to induce inter-RAT handover to UTRAN. In this case, idleModeMobilityControlInfo to be transmitted when the UE is released shall be based on Idle Mode Load Balancing. both (2): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE Radio Capability, attach B1 or B2 event to induce inter-RAT handover to UTRAN. In addition, when the UE is released, the dedicated priority per FA configured in SPID that the UE currently possesses among the FAs that can be supported in UE radio capability is transmitted through IdleModeMobilityControlInfo.

SPID_MEASURE_OPTION_I NTER_RAT

If spidMobilityOption is handoverOnly or both, designate measurement event type to trigger inter-RAT handover to UTRAN. spidHoEventB1(0):measurement event type for inter-RAT handover to UTRAN triggering is EventB1. spidHoEventB2(1):measurement event type for inter-RAT handover to UTRAN triggering is EventB2.

RTRV-GERAN-PRIOR/CHG-GERAN-PRIOR Parameter

Description

CELL_NUM


PLMN_INDEX


FA_INDEX

GERAN frequency index. Up to 6 FAs can be assigned per cell. It is mapping to PLDGeranFaPriorInfo.


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Description

SPID_INDEX

SPID index.

SPID

SPID for RAT/frequency priority. It cannot be set from 129 to 253.

USED_FLAG

Whether to use dedicatedPriority. CI_no_use: dedicatedPriority is not used. CI_use: dedicatedPriority is used.

DEDICATED_PRIORITY

Dedicated Priority Value for Frequency according SPID. According to 3GPP TS36.300, if spid is 254, dedicated priority is set to 7.


Define additional operations based on the mobility setting of the parameter for SPID of the UE. reselectionOnly (0): When UE is released, send the dedicated priority per FA for SPID that the UE currently possesses among the FAs supported in UE Radio Capability through IdleModeMobilityControlInfo. However, B1 or B2 based inter-RAT handover to GERAN based on SPID shall not be performed. handoverOnly (1): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE Radio Capability, attach B1 or B2 event to induce inter-RAT handover to GERAN. In this case, idleModeMobilityControlInfo to be transmitted when the UE is released shall be based on Idle Mode Load Balancing. both (2): When the UE first receives SPID, if the FA configured to be the highest DEDICATED_PRIORITY for the SPID is different from the serving frequency of the UE but can be supported in UE Radio Capability, attach B1 or B2 event to induce inter-RAT handover to GERAN. In addition, when the UE is released, the dedicated priority per FA configured in SPID that the UE currently possesses among the FAs that can be supported in UE radio capability is transmitted through IdleModeMobilityControlInfo.

SPID_MEASURE_OPTION_I NTER_RAT

If spidMobilityOption is handoverOnly or both, designate measurement event type to trigger inter-RAT handover to GERAN. spidHoEventB1(0):measurement event type for inter-RAT handover to GERAN triggering is EventB1. spidHoEventB2(1):measurement event type for inter-RAT handover to GERAN triggering is EventB2.

RTRV-EUTRA-A4CNF/CHG-EUTRA-A4CNF OR RTRV-EUTRAA4CNFQ/CHG-EUTRA-A4CNFQ Parameter

Description

PURPOSE

This parameter is the purpose of using Event A4. IntraLteHandover: Handover is executed. ANR_Specific: The ANR operation is executed. CA: SCELL is configured Sendback: The Sendback operation is executed. InterFrequencyLb: The Active Load Balancing feature is executed. ArpHandover: Enable inter-frequency handover function for UEs that have a specific ARP. OnDemandHandover: Enable the forced handover triggering by operator InterFrequencySPID: inter-frequency handover is executed for specific SPID with handover mobility option.

ACTIVE_STATE

This parameter is the purpose of using Event A4. If this is set to Inactive, the Event A4 is not configured.


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RTRV-EUTRA-A5CNF/CHG-EUTRA-A5CNF OR RTRV-EUTRAA5CNFQ/CHG-EUTRA-A5CNFQ Parameter

Description

PURPOSE

This parameter is the purpose of using Event A5. IntraLteHandover: Used for intra-LTE handover. CaInterFreq: Performs inter-frequency handover for carrier aggregation (CA) UE InterFrequencyMbms: Inter-frequency handover to get MBMS service. ArpHandover: Enable inter-frequency handover function for UEs that have a specific ARP. OnDemandHandover: Enable the forced handover triggering by operator InterFrequencySPID: Inter-frequency handover for the specific SPID with handover mobility option.

ACTIVE_STATE

This parameter is the purpose of using Event A5. If this is set to Inactive, the Event A5 is not configured.

RTRV-UTRA-B1CNF/CHG-UTRA-B1CNF OR RTRV-UTRA-B1CNFQ/CHGUTRA-B1CNFQ Parameter

Description

PURPOSE

This parameter specifies the use of the UTRAN Event B1 used for interoperating with the UTRAN. InterRatHandover: Used for handover to the UTRAN (0). ANR_Specific: Used for the ANR operation with the UTRAN (1). Srvcc: Used for the SRVCC with the UTRAN (2). Mlb: Used for MLB (3). InterRatSPID: Inter-RAT handover is executed for specific SPID with handover mobility option (4).

ACTIVE_STATE

This parameter is the purpose of using Event B1. If this is set to Inactive, the Event B1 is not configured.

RTRV-UTRA-B2CNF/CHG-EUTRA-B2CNF OR RTRV-EUTRAB2CNFQ/CHG-EUTRA-B2CNFQ Parameter

Description

PURPOSE

This parameter is the purpose to retrieve the B2 report configuration information used for interoperating with the UTRAN. InterRatHandover: Used for handover to the UTRAN (0). Srvcc: Used for SRVCC (1). InterRatSPID: inter-RAT handover is executed for specific SPID with handover mobility option (2).

ACTIVE_STATE


RTRV-GERAN-B1CNF/CHG-GERAN-B1CNF OR RTRV-GERANB1CNFQ/CHG-GERAN-B1CNFQ Parameter

Description


451


Description

PURPOSE

This parameter is the usage of information on the GERAN Event B1 report. It is used for inter-RAT Handover and SON ANR function. InterRatHandover: Used for inter-RAT handover (0). ANR_Specific: Used for SON ANR (1). Srvcc: Used for SRVCC (2). Mlb: For MLB (3). InterRatSPID: Inter-RAT handover is executed for specific SPID with handover mobility option (4).

ACTIVE_STATE


RTRV-GERAN-B2CNF/CHG-GERAN-B2CNF OR RTRV-GERANB2CNFQ/CHG-GERAN-B2CNFQ Parameter

Description

PURPOSE

This parameter is the usage of the GERAN Event B2 report. It is used for interRAT handover (0). InterRatHandover: For inter-RAT handover (0). Srvcc: For SRVCC (1). InterRatSPID: Inter-RAT handover is executed for specific SPID with handover mobility option (2).

ACTIVE_STATE



REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification [3] 3GPP TS36.304 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode


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Chapter 5

RAN Sharing

LTE-SW5001, Multi-PLMN Support INTRODUCTION Multiple-PLMN support allows provide LTE service to subscribers of multiple operators in a cell concurrently. For Multiple-PLMN support, eNB broadcasts multiple PLMN IDs which are sharing a cell in system information and supports UE associated signaling with a UE and an appropriated core network based on the PLMN which UE has selected. In RAN sharing, operators have their own dedicated carrier. The Multi-PLMN Support feature allows serving only one available PLMN ID to the subscribers of the dedicated carrier. The PLMN ID served in the cell is either primary or secondary PLMN, which depends on operator's ownership of the dedicated carrier. The primary PLMN ID is included in the broadcasted PLMN list to support successful ANR operation. It is marked as reserved for operator use to avoid access from primary PLMN subscribers when the carrier is only available for secondary PLMN. The Multiple Operator Core Network (MOCN) has the RAN structure where multiple partner operators share one spectrum. Whereas, in MORAN structure, each partner operator uses dedicated frequency, however, shares same eNB. In general, one host operator manages the RAN in the MOCN or MORAN structure, and other partner operators provide services for users through the RAN. The host operator can check the data usage through the statistical information. However, partner operators cannot access this data without host operator's help. This feature provides a function to collect data usage by PLMN ID in the eNB for each partner operator. The collected data is transmitted to the LSM. The provider can check the data used by the partner operators.

BENEFIT Multiple operators can share eNB in MORAN architecture. Operator can reduce CAPEX and OPEX by sharing site, eNB and backhaul network with partners.

Host operator can figure out how much data is consumed by each partner operator.

The data usage can be utilized for the purpose of settlement among partner operators.


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Chapter 5 RAN Sharing

DEPENDENCY AND LIMITATION Dependency Required Network Elements: For usage reporting function, in addition to eNB, the LSM should support this feature.

Related Radio Technology: E-UTRAN (LTE) Others: Each partner operator must have their own dedicated carrier for Multiple Operator Radio Access Network (MORAN). Limitation The feature supports a maximum of six dedicated carriers per eNB.

FEATURE DESCRIPTION The eNB provides the following functions for this feature:



Broadcast multiple PLMN IDs, up to six, in SIB.

Routing of signaling for call control based on the selected PLMN ID by UE. Inter-PLMN handover support in shared network. Radio resource sharing in shared cell. In a shared cell, the eNB broadcasts the supporting PLMN ID list, up to six, through SIB1. The first PLMN ID broadcasted to SIB 1 must be set to the same as the PLMN ID of the global eNB ID. The first listed PLMN must be the same as the primary PLMN of eNB. The supporting PLMN ID list per cell is configured by the system parameter. The UE reads the PLMN IDs, and selects one based on its selection process. When the UE is expected to make RRC connection with eNB, the selected PLMN ID is included in the RRC Connection Setup Complete message. The eNB uses this PLMN ID to select the core network, and to transfer the Initial UE message. Figure below depicts the signaling procedures of eNB.


454


Multiple Operator Support with Dedicated Carriers In MORAN architecture, operators do not have to share spectrum. One possible scenario is that operators have its own dedicated carrier and do not share with others. The Multi-PLMN Support feature enable operator to share eNB with its own dedicated carrier.


455


Figure below shows an eNB sharing scenario with dedicated carrier between operator A and B. While the operator A is the owner or manager of the shared eNB and the operator B shares the eNB with a dedicated carrier. In the dedicated carrier cells of each operator, only one PLMN ID is available, which provide services to the subscribers of the carrier owner.

Definitions used to describe the relation between PLMN ID and the dedicated carrier owner.

Owner PLMN: The operator‟s PLMN ID that is the eNB owner or manager of the eNB.

Sharing PLNM: The operator‟s PLMN ID that shares eNB with a dedicated carrier with eNB owner operator. The rules for PLMN broadcasting in the dedicated carrier cells are as follows:

In the dedicated carrier cells of eNB owner or manager: Only PLMN ID of owner PLMN is broadcasted in SIB1 as the primary PLMN. In the dedicated carrier cells that shares eNB with owner operator: Two PLMN IDs shall be broadcasted in SIB1 (owner PLMN + sharing PLMN). Owner PLMN ID shall be the primary PLMN and sharing PLMN ID shall be the secondary PLMN.

Owner PLMN, that is primary PLMN in SIB1, shall set to 'reserved for operator' to prevent provide services to owner PLMN‟s subscribers in sharing PLMN operator‟s dedicated carrier.


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The reason for including PLMN ID of owner PLMN in sharing PLMN carrier is to enable SON related operation, for example ANR, and packets forwarding issue in the shared eNB. This feature supports up to 6 operators dedicated carriers MOCN sharing operation.

Network Management for RAN Sharing In the RAN sharing structure, such as MOCN or MORAN, the host operator is responsible for RAN management. The host operator manages the fault, configuration, administration, performance, and statistics of the RAN shared with partner operators through the LSM. The partner operators control the RAN through the host operator rather than changing the system parameter by directly accessing to the RAN. The statistical information is stored periodically in the LSM and managed by the PLMN ID. Through the north bound interface, the LSM can forward the operator specific and common statistics to each operator's OSS respectively, as shown in figure below.

EMS Clients for Partners RAN is controlled and maintained by one operator. Other partners monitor or query the network or usage information. Access level from an EMS client to the main EMS can be changed according to the agreement between the host operator and partners. Figure below depicts the relationship of main and client EMSs.


457


Statistics Collected per PLMN The information collected in the eNB by the PLMN ID is outlined in table below. This statistics can be changed for a specific operator SW PKG, or for a Single RAN SW PKG. For example, in SSR3.0, Bearers and Data usage categories were excluded. Category

Items

Classification Level

Comments

PRB Usage

DL PRB Usage

Per PLMN/Cell

Average number of PRBs allocated to each PLMN during a certain time period.

Per PLMN/Cell

Average and peak number of RRC_Connected users during a certain time period.

Per PLMN/Cell/QCI

Average and peak number of bearers during a certain timer period.

Per PLMN/Cell/QCI Per PLMN/Cell

Total number of bytes delivered to or from UE. Uncompressed packets are measured at PDCP/RLC/MAC layer.

Per PLMN/Cell

DL/UL RRC/S1/X2 messages.

UL PRB Usage Active UEs

Average number of active UEs Maximum number of active UEs

Bearers

Average number of Bearers Maximum number of Bearers

Data Usage

Total number of Bytes (DL) Total number of Bytes (UL) Total number of Bytes (DL) Total number of Bytes (UL)

Signaling Messages

Total number of signaling messages (DL) Total number of signaling messages (DL) (UL)

SYSTEM OPERATION How to Activate To add additional PLMN ID broadcasted to the specific cell, do the following:


458


1 Execute RTRV/CHG-ENBPLMN-INFO to configure additional PLMN ID (= MCC + MNC) to the unused PLMN_IDX.

2 Execute RTRV/CHG-CELLPLMN-INFO to set PLMN_USAGE of the newly specified PLMN ID with the specific cell and the corresponding PLMN_IDX.

Key Parameters RTRV-ENBPLMN-INFO/CHG-ENBPLMN-INFO Parameter

Description

PLMN_IDX

The plmn index to be changed or retrieved. PLMN ID coreresponding to the selected plmnIdx is mapped to the PLMN ID which is retrieved or changed by command RTRV/CHG-ENBPLMN-INFO with the same plmnIdx number.

MCC[4]

Mobile Country Code (MCC) that comprises Public Land Mobile Network (PLMN).

MNC[4]

Mobile Network Code (MNC) that comprises Public Land Mobile Network (PLMN).

MCC/MNC of the PLMN_IDX = 0 is representative PLMN ID of the system operator, and cannot be changed by CHG-ENBPLMN-INFO.

RTRV-CELLPLMN-INFO/CHG-CELLPLMN-INFO Parameter

Description

CELL_NUM


PLMN_IDX

The plmn index to be changed or retrieved. PLMN ID coreresponding to the selected plmnIdx is mapped to the PLMN ID, which is retrieved or changed by command RTRV/CHG-ENBPLMN-INFO with the same plmnIdx number.

PLMN_USAGE

When cell is operated, determine whether to use the value of PLMN corresponding plmnIdx. use: The value of PLMN corresponding plmnIdx can be serviced. no_use: The value of PLMN corresponding plmnIdx not be serviced.


Type Name

Type Description

RRC Connection number (PLMN)

ConnNo_PLMN

The average value of the number of RRC connections periodically collected.

ConnMax_PLMN

The maximum value of ConnNo_PLMN.

UsageNbr_PLMN

Average E-RAB count per unit time.

UsageNbrMax_PLMN

Maximum E-RAB count per unit time.

E-RAB Simultaneous Number (PLMN)


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Chapter 5 RAN Sharing Family Display Name

S-GW UL/DL packets (PLMN)

DL/UL Total PRB Usage (PLMN)

DL/UL Total PRB Usage (PLMN)

Type Name

Type Description

UsageNbr_QCI_x

Average E-RAB count per unit time (QCIx).

UsageNbrMax_QCI_x

Maximum E-RAB count per unit time (QCIx).

ByteUleNBQCI_QCIx

Bytes of user of QCI (x) data sent from the eNB to the S-GW.

ByteDleNBQCI_QCIx

Bytes of user of QCI (x) data sent from the S-GW to the eNB.

TotPrbDl_PLMN

Total PRB Usage for PDSCH/PDCCH transmission per PLMN.

TotPrbDlMin_PLMN

TotPrbDl_PLMN minimum.

TotPrbDlMax_PLMN

TotPrbDl_PLMN maximum.

TotGbrPrbDl_PLMN

Total PRB usage for downlink GBR traffic transmission per PLMN.

TotGbrPrbDlMin_PLMN

TotGbrPrbDl_PLMN minimum.

TotGbrPrbDlMax_PLMN

TotGbrPrbDl_PLMN maximum.

TotNGbrPrbDl_PLMN

Total PRB usage for downlink non-GBR traffic transmission per PLMN.

TotNGbrPrbDlMin_PLMN

TotNGbrPrbDl_PLMN minimum.

TotNGbrPrbDlMax_PLM N

TotNGbrPrbDl_PLMN maximum.

TotPrbUl_PLMN

Total PRB usage for PUSCH transmission per PLMN.

TotPrbUlMin_PLMN

TotPrbUl_PLMN minimum.

TotPrbUlMax_PLMN

TotPrbUl_PLMN maximum.

TotGbrPrbUl_PLMN

Total PRB usage for uplink GBR traffic transmission per PLMN.

TotGbrPrbUlMin_PLMN

TotGbrPrbUl_PLMN minimum.

TotGbrPrbUlMax_PLMN

TotGbrPrbUl_PLMN maximum.

TotNGbrPrbUl_PLMN

Total PRB usage for uplink non-GBR traffic transmission per PLMN.

TotNGbrPrbUlMin_PLMN

TotNGbrPrbUl_PLMN minimum.


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Chapter 5 RAN Sharing Family Display Name

PROTOCOL_MSG

Type Name

Type Description

TotNGbrPrbUlMax_PLM N

TotNGbrPrbUl_PLMN maximum.

RrcMsgSnd

Sent the number of times in the RRC protocol Msg eNB.

RrcMsgRcv

The number received in the RRC protocol Msg eNB.

S1MsgSnd

Sent the number of times in the S1AP protocol Msg eNB.

S1MsgRcv

The number received in the S1AP protocol Msg eNB.

X2MsgSnd

Sent the number of times in the X2AP protocol Msg eNB.

X2MsgRcv

The number received in the X2AP protocol Msg eNB.

If the operator does not use RAN sharing feature, some family of the statistics listed above can be removed.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification [3] 3GPP TS23.251 Network Sharing; Architecture and functional description


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LTE-SW5002, Flexible Radio Resource Configuration for RAN Sharing INTRODUCTION In RAN sharing deployment scenario, one radio spectrum can be shared by several providers, how to share and use wireless resources among providers is important. Samsung eNB provides the very flexible method for the provider sharing or dividing and using wireless resources. This allows a variety of business models including the integrated operation of the radio spectrum among providers, pricing based on wholesale or usage of the wireless resources, and so on. To share or divide wireless resources, Samsung eNB supports four resources sharing models: Full Common Sharing, Strict Separation, Partial Common Sharing, and Adaptive Sharing. The operator can configure resource partitioning percentages among providers and accordingly the eNB controls the amount of resources allocated by provider.

The Full Common Sharing is a method for sharing radio resource in a first-comefirst serve form regardless of providers;

Strict Separation is a method for allowing providers to partition wireless resource and allocating certain portion of the resource only for a designated provider;

Partial Common Sharing is a method in a hybrid form of full common sharing and strict separation as for part of the whole radio resource being used regardless of providers and the other part being allocated as dedicated resource to each provider; and

In Adaptive Sharing, even the resources allocated as dedicated resources may be allocated to other providers even though they are not used by the corresponding provider. As such, the use of resource partition may be set based on a certain period of time and the peak throughput of the UE is not restricted. The peak throughput of the UE is available as much as permitted by air bandwidth. The radio resources can be shared up to six providers.

BENEFIT This enables the business model where operators can wholesale a portion of spectrum.

Operators can highly utilize radio resources between different PLMNs by configuring radio resource sharing ratio among them.

In addition to radio spectrum, operators can share site, eNB equipment, and backhaul network to reduce CAPEX and OPEX. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Prerequisite Features LTE-SW5001, Multiple PLMN support

Others A common carrier that is shared by multiple PLMNs. If Per-PLMN CAC feature in LTE-SW5012 is enabled, this feature should be also enabled.

LIMITATION A common carrier is shared among up to 6 operators Radio sharing ratio can be set by the unit of 1 %

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Interdependencies between Features Interdependent Feature: LTE-SW5012, Operator Specific Feature Activation If Per-PLMN CAC feature in LTE-SW5012 is enabled, this feature should be also enabled.

FEATURE DESCRIPTION Radio Resource Sharing Models Samsung eNB supports four kinds of radio resource sharing models as follow:

Full Common Sharing of Resource: Multiple operators share all radio resources. The eNB allocates resources in the first-come-first-serve format according to the request of the UE regardless of the classification of the operator. The operator enters the resource sharing ratio by PLMN as 0. In conclusion, 100 % of all the resources are operated as common resources in the system.

Strict Separation of Resource: Partition and allocate all radio resources by operator. Each operator may use it as much as designated portion, and even though the resources are left because another operator has not used them, the resources cannot be used. The sum of the resources allocated to the operator must be 100 %.


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Partial Common Sharing of Resource: Share among operators by designating part of resources as common resources. The operator automatically allocates the left part of dedicated resources by PLMN after being allocated in the system. Each operator additionally uses common resources other than the dedicated resource allocated to him or her. The common resource is allocated to the UE based on the first-come-first serve format regardless of classification of operators.

Adaptive Sharing of Resource: Just like the Partial Common Sharing of Resource model, allocate dedicated resource to each operator. If all dedicated resources are not used and are completely left, the resource holding operator allows other operators to use them. The left dedicated resources after being allocated to each operator is designated internally as common resources in the system and the resources are allocated to the UE based on the first-come-first serve format regardless of classification of operators.

Each operator (PLMN) can designate Minimum Dedicated Resource Reservation (MinDRR) and Maximum Dedicated Resource Reservation (MaxDRR) values. In the aforementioned example (Adaptive Sharing of Resource), the MinDRR value of Operator A is 5 % and the MaxDRR value is 35 %. In addition, in case of the Partial Common Sharing of Resource, the MinDRR of Operator A is 40 % and the MaxDRR is 40 %.


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For example, if the MinDRR and MaxDRR values of Operator C are same, Operator C guarantees dedicated resources as much as the MaxDRR value all the time and does not use any of the left dedicated resource for other operators. Conversely, if the MinDRR and MaxDRR values of Operator C are different, the resources not used by Operator C as much as MaxDRR-MinDRR value can be allocated for other operators. At the time, the resources allocated to other operators, if necessary, can be immediately withdrawn and used by Operator C. If there are the resources allocated and left as dedicated resources to each operator (100 % - (Sum of MaxDRRs)), the resources are allocated as common resources internally in the system in the first-come-first-server format regardless of the classification of operators. Among the four resource-sharing models as explained above, three models including Full Common Sharing, Partial Common Sharing, and Adaptive Sharing can be independently applied by operator. For example, Operator A may apply the Partial Common Sharing and at the same time Operator B may apply Adaptive Sharing. However the Strict Separation must be applied to all operators at the same time, and at the time, the sum of MaxDDR must be 100 %. In such configuration, a specific operator does not allocate any left dedicated resources to any other operator and does not use the resources of any other operators even though the resource is insufficient due to congestion. The resource-sharing ratio configured by the operator is applied when each scheduler allocates DL and UL resources or performs call admission control for the UE and the bearer. For example, in the network operating the 20 MHz bandwidth, Operator A can get the allocated resource as much as 100 PRB x T x 40 %, accept the UEs as many as 600UEs x 40 % per cell at the same time and also the bearers as many as 1200 Bearers x 40 %.

PRB Resource Allocation and Method among PLMNs The method for allocating and sharing resources among PLMNs in the eNB is as follows:


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1 TTresh is automatically changed depending on the result of resource allocation of the previous time duration T between the MinDRR value and the MaxDRR value according to the setting value by PLMN. If the reserved resources as many as TTresh as the result of the resource allocation to the operator in the T zone was insufficient, increase the TTresh value in the 2T zone and if the resources were left, reduce TTresh as much. The TTresh value is not increased higher than the MaxDRR value and is not reduced less than the MinDRR value. During T, for the operator, the dedicated resource as much as TTresh is allocated, and the resource is not allocated to any other operators even though it is not used. In the example, the resource as much as 100 %-TTresh (A)TTresh (B) is used as common resources.

2 According to the result of the resource allocation of Operators A and B during the T zone, each TTresh was changed in the 2T zone. But due to many resources requested by each operator, the resource in the common resource area beyond TTresh is used. The common resource is allocated in the firstcome-first-serve format regardless of classification of PLMNs.

3 Due to many resources requested by each of Operator A and B, TTresh increased to MaxDRR and congestion occurred because all the resources in the common resource area were used.

4 Because Operator A requests many resources, some of common resource is used and Operator B did not use all dedicated resources because the requested resources were reduced.

5 In the 5T zone, the TTresh value of Operator B was adjusted by reflecting the result of resource allocation in the 4T zone. Operator B cannot use all the reserved resources as TTresh, but Operator A additionally uses the resource as much as the MaxDRR-TTresh of Operator B. Even though Operator A is in the congestion, the resource reserved to Operator B that is not used cannot be allocated to Operator A.

6 Due to the increased request of Operator B for resources, the resource reserved as TTresh becomes insufficient.

7 According to the result of the resource allocation in the 6T zone, the TTresh of Operator B is increased to MaxDRR to secure dedicated resources that can be used by Operator B. At the time, Operator A still requests many resources, but the available resources are reduced. As such, resource allocation and shared algorithm are equally applied for DL and UL resources.

UE Connection and Bearer Resource Allocation and Sharing Method among PLMNs When the cell is at the normal state, the RRC Connection and Bearer resources are allocated to the UE regardless of classification of operators in the first-come-firstserve format. If the resources are insufficient due to the increased load, the operator who uses fewer resources than the given quota gets additional resources but the one who uses more than the given quota cannot get additional resources. To provide resources additionally for an operator at the congestion, the resources must be withdrawn from the operator who uses more resources than the given quota. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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In case of the quota per operator means, the operator uses the Maximum Dedicated Resource Reservation (MaxDRR) and Minimum Dedicated Resource Reservation (MinDRR) values set by PLMN and the meaning is as same as defined in the Radio Resource Sharing model. The fewer resources-using operator is defined as the operator who uses fewer resources than the given quota and the resource-overusing operator as the operator who uses more resources than the given quota. If a subscriber of the fewer resources-using operator requests a call at the congestion, the eNB preempts the subscriber of the resource-overusing operator and accepts the call in a method for providing the secured resources for the subscriber of the fewer resources-using operator. If the subscriber of the resource-overusing operator requests a call at the congestion, the eNB accepts the call in a method for preempting the UE which belongs to the same operator. When preemption is applied among PLMNs, the two following options are provided and the operator may select either option:

Option 1) Overusing PLMN First. Select candidate UEs first from resourceoverusing operators, that is, UE form PLMN that has the most overused resources. And then choose the UE with the bearer with lowest ARP of that selected PLMN. If there are still multi candidates exist, then randomly select the preemption candidate.

Option 2) Lowest ARP First. Select candidate UEs who has the bearer with lowest ARP first, and then select the UEs from PLMN that has the most overused resources. If there are still multiple candidates, then randomly select the preemption candidate.


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Considerations in QoS If the congestion occurs, the contention for the resource occurs in the resource allocated to a specific operator. QoS-based CAC determines the supportability of QoS based on the Maximum Dedicated Resource Reservation (MaxDRR) resource allocated by PLMN. For this, the operator may set maximum number of GBR Bearers, and maximum PRB usage of GBR Bearers by PLMN. At the time, the number of GBR Bearers and maximum PRB usage available by GBR Bearer must be set not to exceed the MaxDDR of the provider. Otherwise, at the congestion, the QoS of GBR Bearer may be poorer. Furthermore, the weight factor for differentiation of the service by non-GBR QCI may be set by PLMN. The weight factor defined for a specific operator does not give any influence over any other operators.

Resource Access Management by Operator The operator may set whether the common resource by partner operator and the shared resource of other operators will be allowed to be, or restricted from being, used. For example, on condition that the only common resource is allowed to be used for Operator A and the use of the shared resource of other operators is restricted, if Operator A uses all of its dedicated resource and can use the only common resource, even though the dedicated resource of Operator B is left, Operator A cannot use the left resource. (Available in 4Q of 2013)


How to Activate This section provides the information that you need to configure the feature. Preconditions LTE-SW5001 Multiple PLMN feature must be supported as a precondition. Activation Procedure To activate this feature, do the following:

Run CHG-ENBPLMN-INFO and CHG-CELLPLMN-INFO to configure PLMN IDs to be used in a specific eNB. oMultiple PLMNs shall be configured for the carrier to be shared in a MOCN cell.

Run CHG-CELL-CAC to enable use of adaptive sharing and to select RAN sharing pre-emption option.

Run CHG-NET-SHR to configure Minimum and Maximum Resource Portion. Deactivation Procedure To deactivate this feature, do the following: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Run CHG-NET-SHR to remove Minimum and Maximum Resource Portion. Run CHG-CELL-CAC to disable use of adaptive sharing. Run CHG-RSHR-PLMN4G and CHG-CELLPLMN-INFO to remove PLMNs except a primary PLMN.

Key Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Activation/Deactivation Parameters RAN Sharing support can be activated/deactivated using below parameters. Parameter Descriptions of CHG-CELLPLMN-INFO/RTRV-CELLPLMN-INFO Parameter

Description

CELL_NUM

This parameter is the cell number to identify each cell. This value must not exceed the maximum number of cells supported by the system.

PLMN_IDX

This parameter is the Public Land Mobile Network (PLMN) index. The PLMN ID corresponding to the selected PLMN_IDX is mapped to the PLMN ID which is retrieved/changed by command RTRV/CHG-ENBPLMN-INFO with the same PLMN_IDX number. A PLMN is identified by the Mobile Country Code(MCC) and the Mobile Network Code(MNC).

PLMN_USAGE

When cell is operated, determine whether to use the value of PLMN corresponding PLMN index. use: the value of PLMN corresponding PLMN index can be serviced. no_use: the value of PLMN corresponding PLMN index not be serviced.

Parameter Descriptions of CHG-CELL-CAC/RTRV-CELL-CAC Parameter

Description

CELL_NUM


ADAPTIVE_SHARING_US AGE

Whether to use Adaptive RAN sharing no_use: Adaptive RAN sharing is not used. use: Adaptive RAN sharing is used.

RS_PREMPTION_OPTIO N

The policy of RAN sharing preemption. overUsingPLMNfirst: For a RAN sharing, PLMN is selected based on overusing PLMN. Then PLMN is selected based on the lowest ARP. lowestARPfirst: For a RAN sharing, PLMN is selected based on the lowest ARP. Then PLMN is selected based on overusing PLMN.

Configuration Parameters Parameter Descriptions CHG-ENBPLMN-INFO/RTRV-ENBPLMN-INFO For PLMN_ID = 0, MCC and MNC should be fixed to primary PLMN. Parameter

Description

PLMN_ID

This parameter is the Public Land Mobile Network (PLMN) index. The PLMN ID corresponding to the selected PLMN_IDX is mapped to the PLMN ID which is retrieved/changed by command RTRV/CHG-ENBPLMN-INFO with the same


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Chapter 5 RAN Sharing Parameter

Description PLMN_IDX number. A PLMN is identified by the Mobile Country Code(MCC) and the Mobile Network Code(MNC).

MCC

Mobile Country Code (MCC) that comprises Public Land Mobile Network (PLMN). It is noted that MCC of PLMN_IDX = 0 cannot be changed and used for the representative PLMN, which is included in the Global eNB ID.

MNC

Mobile Network Code (MNC) that comprises Public Land Mobile Network (PLMN). It is noted that MNC of PLMN_IDX = 0 cannot be changed and used for the representative PLMN, which is included in the Global eNB ID.

OP_ID

This parameter is an operator index which share resources in this system.

Parameter Descriptions of CHG-NET-SHR/RTRV-NET-SHR Parameter

Description

CELL_NUM


PLMN0_PORTION ~ PLMN5_PORTIN

This parameter is maximum portion of PLMN0~PLMN5.

PLMN0_PORTION_MIN ~ PLMN5_PORTION_MIN

This parameter is minimum portion of PLMN0~PLMN5.

COMMON_SHARING_PO RTION

This parameter is maximum portion of common

1 PLMN0_PORTION + PLMN1_PORTION + PLMN2_PORTION + PLMN3_PORTION + PLMN4_PORTION + PLMN5_PORTION + COMMON_SHARING_PORTION = 100

2 PLMN0_PORTION_MIN <= PLMN0_PORTION, PLMN1_PORTION_MIN <= PLMN1_PORTION, PLMN2_PORTION_MIN <= PLMN2_PORTION, PLMN3_PORTION_MIN <= PLMN3_PORTION, PLMN4_PORTION_MIN <= PLMN4_PORTION, PLMN5_PORTION_MIN <= PLMN5_PORTION.


Type Name

Type Description

PRB Usage

PrbDLAvg

The average use rate for PRBs used for each QCI in order to transmit DTCH traffic for the downlink during the collection interval.

PrbULAvg

The average use rate for PRBs used for each QCI in order to transmit DTCH traffic for the uplink during the collection interval.

REFERENCE [1] 3GPP TS23.251, Network Sharing; Architecture and functional description eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[2] 3GPP TS22.951, Service aspects and requirements for network sharing


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Chapter 6

Radio Scheduler

LTE-ME0508, Sounding Reference Signal INTRODUCTION In LTE there are two types of Reference Signals (RS) defined in uplink:

Demodulation Reference Signals (DMRS), which are transmitted on uplink resources assigned to UE, are for coherent demodulation of data and control information at eNB. As PUCCH cannot be transmitted simultaneously with PUSCH, DMRS is defined for each of them.

Sounding Reference Signal (SRS) can be used to measure the uplink channel quality over a section of channel bandwidth. The eNB can use this information for uplink frequency selective scheduling and link adaptation. When uplink/downlink channel reciprocity is determined, measurements from SRS can also be used to support downlink transmission. For example, SRS can be used to support Angle of Arrival (AoA) measurements for downlink beamforming. The channel reciprocity is most applicable to TDD in which case the same RF carrier is used for uplink and downlink transmissions. The SRS is introduced in the release 8 version of 3GPP specifications, and is subsequently enhanced in the release 10 version. Enhancements include support for uplink MIMO and rapid triggering of SRS transmissions using a flag in the Downlink Control Information (DCI). The reason for having two types of RS in uplink is because, unlike the downlink, DMRS in uplink are only transmitted on subcarriers assigned to UE. Therefore, this cannot provide sufficient wideband channel quality information for resource allocation, particularly over the resource blocks that are not allocated to UE. Unlike downlink, RS in uplink cannot be transmitted at the same time as user data. Instead, uplink RS are time division multiplexed with the uplink data in the assigned subcarriers. The power level of RS can be different from the data symbol as they are transmitted over different SC-FDMA symbols, so the PAPR is minimized over each SC-FDMA symbol.

BENEFIT The eNB can estimate uplink channel response by receiving this signal. The channel estimate can be utilized in the next uplink scheduling.



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Chapter 6 Radio Scheduler

FEATURE DESCRIPTION The SRS is transmitted in the last SC-FDMA symbol at the subframe, as shown in table below. The sending interval of SRS by UE is between 2 ms and 320 ms. The SRS sequence provides the index for Cyclic Shift (CS) from 0 to 7. Accordingly, if other indices for CS are used, multiple UEs are possible to transmit SRS at the same time on the same frequency resources. In addition, SRS is not transmitted over all subcarriers of RB. However, it is transmitted in a comb pattern by selecting an even or odd subcarrier. If two different transmission comb patterns are used, two UEs with the same CS index can transmit SRS on the same time and frequency resources. The assignment of the subframe resource of the cell for transmitting SRS is set through srs-SubframeConfig, consisting of four bits (cell-specific SRS). The following two tables represent the indices for srs-SubframeConfig and the corresponding periods and offset values of SRS in the case of FDD and TDD. For example, if srs-SubframeConfig is set to 3 in an FDD cell, SRS is transmitted at every 5 ms with the subframe offset {0} in the cell. In case of TDD, srsSubframeConfig 14 and 15 are not used. Table below shows the frame structure type 1 sounding reference signal subframe configuration. Frame structure type 1 sounding reference signal subframe configuration. SRS-SubframeConfig

Binary

Configuration Period (subframes)

Transmission offset (subframes)

0

0000

1

{0}

1

0001

2

{0}

2

0010

2

{1}

3

0011

5

{0}

4

0100

5

{1}

5

0101

5

{2}

6

0110

5

{3}

7

0111

5

{0, 1}

8

1000

5

{2, 3}

9

1001

10

{0}

10

1010

10

{1}

11

1011

10

{2}

12

1100

10

{3}

13

1101

10

{0, 1, 2, 3, 4, 6, 8}

14

1110

10

{0,1, 2, 3, 4, 5, 6, 8}

15

1111

Inf.

N/A

Frame structure type 2 sounding reference signal subframe configuration. SRS-SubframeConfig

Binary



0

0000

5

{1}

1

0001

5

{1,2}

2

0010

5

{1,3}


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Chapter 6 Radio Scheduler SRS-SubframeConfig

Binary



3

0011

5

{1,4}

4

0100

5

{1,2,3}

5

0101

5

{1,2,4}

6

0110

5

{1,3,4}

7

0111

5

{1,2,3,4}

8

1000

10

{1,2,6}

9

1001

10

{1,3,6}

10

1010

10

{1,6,7}

11

1011

10

{1,2,6,8}

12

1100

10

{1,3,6,9}

13

1101

10

{1,4,6,7}

14

1110

reserved

reserved

15

1111

reserved

reserved

The number of RBs over which SRS is transmitted, that is, SRS bandwidth, is determined by the cell-specific parameter SRS-BandwidthConfig. An example of SRS bandwidth in10 MHz bandwidth is shown in table below. SRS bandwidth configuration

SRS-Bandwidth B_SRS = 0




m_SRS, 0

N0

m_SRS, 1

N1

m_SRS, 2

N2

m_SRS, 3

N3

0

48

1

24

2

12

2

4

3

1

48

1

16

3

8

2

4

2

2

40

1

20

2

4

5

4

1

3

36

1

12

3

4

3

4

1

4

32

1

16

2

8

2

4

2

5

24

1

4

6

4

1

4

1

6

20

1

4

5

4

1

4

1

7

16

1

4

4

4

1

4

1

The number of RBs over which the SRS is transmitted is denoted by m_SRS, 0 to m_SRS, 3. Each value is determined by the cell-specific parameter SRS-BandwidthConfig. The number of RBs assigned to UE is determined according to the UE-specific parameter SRS-Bandwidth between 0 and 3. For example, if SRS-BandwidthConfig is 3, 36 RBs are assigned to SRS bandwidth, and if SRS-Bandwidth is configured to 2 for UE, it transmits SRS in the size of 4 RBs. Whether the frequency hopping of SRS is used is determined according to two UE-specific parameters, 'SRS-Bandwidth' and 'SRS-Hopping-Bandwidth'.


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SYSTEM OPERATION How to Activate You can activate or deactivate this feature. The initial setting is configured depending on the operator/eNB type. The period, subframe configuration, and bandwidth configuration of SRS are determined by scheduling operation.

Execute the CHG-DPHY-ULSRS or RTRV-DPHY-ULSRS commands to change the configuration required to operate dedicated UL SRS or retrieve its information, respectively.

Execute the CHG-SRS-IDLE or RTRV-SRS-IDLE commands to change the parameter required to allocate SRS resources in the specified cell or retrieve its information, respectively.

Execute the CHG-SNDRS-CONF or RTRV-SNDRS-CONF commands to change the configuration of UL SRS in eNB or retrieve its information, respectively.

Key Parameters CHG-DPHY-ULSRS/RTRV-DPHY-ULSRS Parameter

Description

CELL_NUM


DURATION

The transmission duration of Sounding RS. 0: Sounding RS is transmitted only once. 1: Sounding RS is transmitted repeatedly until it is disabled.

CHG-SRS-IDLE/RTRV-SRS-IDLE Parameter

Description

CELL_NUM


FORCED_MODE

Whether to set the PLD change regardless of the cell status. False: The PLD change is set according to the cell status. True: The PLD change is set regardless of the cell status.

SRS_USAGE

This parameter indicates whether the SRS is used/not used. no_use: SRS is not used. use: SRS is used.

CHG-SNDRS-CONF/RTRV-SNDRS-CONF Parameter

Description

CELL_NUM


ACK_NACK_SRS_SIMUL_ TRANSMISSION

This is defined to enable simultaneous transmission of ACK/NACK or SR, and sounding RS.


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Chapter 6 Radio Scheduler Parameter

Description False: Sounding RS is not transmitted. (only PUCCH carrying ACK/NACK or SR is transmitted) True: Sounding RS and PUCCH can be transmitted simultaneously.

The parameters listed below are accessible and configurable when the DL Smart (LTE-ME6004) feature is enabled. CHG-DPHY-ULSRS/RTRV-DPHY-ULSRS Parameter

Description

SRS_POOL_IDX0

SRS Pool Index array (-1 (0xff): not allocated)

SRS_POOL_IDX1


CHG-SRS-IDLE/RTRV-SRS-IDLE Parameter

Description

smartSrsEnable

This parameter indicates which scheduling mode is applied to SRS resource allocation. False: Macro mode True: Smart mode

CHG-SRSNBR-CONF/RTRV-SRSNBR-CONF Parameter

Description

CELL_NUM


SRS_NBR_IDX

SRS neighbor cell idx.

STATUS

The validity of the SRS neighbor cell information.

ENB_ID

The eNB ID of the eNB to which SRS neighbor cell to the eNB belongs. If the enbType value is macro eNB, 20 bit of the value is eNB ID. If the enbType value is home eNB, 28 bit of the value is eNB ID. It is used when creating a cell identifier.

TARGET_CELL_NUM

The local cell ID of SRS neighbor cell to the eNB. It is used when creating a cell identifier.

CLUSTER_ID

This is the cluster ID to which the eNB belongs.

SRS_POOL_IDX0


SRS_POOL_IDX1




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LTE-ME1101, PDSCH Resource Allocation INTRODUCTION In SC-FDMA or OFDM system, the frequency-domain resource allocation information needs to be signaled to UE. Because of the large number of Resource Blocks (RBs) within the frequency band, the resource allocation is one of the largest fields in the downlink control information. In the case of SC-FDMA uplink, the allocated RBs need to be contiguous to guarantee single-carrier property. While the contiguous resource allocation can be signaled with the minimum of signaling bits, it also results in limiting the scheduling flexibility. In the case of OFDM, non-contiguous RBs can be allocated thus providing maximum scheduling flexibility. However, the signaling overhead also increases for non-contiguous RB allocation. To provide various choices of scheduling performance and signaling overhead, multiple resource allocation types are defined. A contiguous resource allocation scheme is defined for both and the uplink and the downlink. As pointed out earlier, a contiguous resource allocation is necessary in uplink due to singlecarrier access. In downlink, contiguous resource allocation provides a low overhead alternative while limiting scheduling flexibility. In addition to contiguous resource allocation, two types of non-contiguous resource allocation using a bitmap-based signaling are defined for downlink.

BENEFIT This feature enables to enhance flexibility in spreading the resources across the frequency domain to exploit frequency diversity.

DEPENDENCY AND LIMITATION Limitation Type 1 Resource Block (RB) allocations are not applicable to the 1.4 MHz channel bandwidth.

DCI formats 1, 2, and 2A always signal a type 0 RB allocation when the channel bandwidth is 1.4 MHz.

FEATURE DESCRIPTION 3GPP LTE defines three downlink resource allocation types as follows:

Downlink Resource Allocation Type 0 A type 0 downlink RB allocation can be signaled from eNB to UE using Downlink Control Information (DCI) format 1, 2, and 2A.

An allocation received during downlink subframe „n‟ defined the allocated RBs within the same downlink subframe.


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A type 0 RB allocation uses a bitmap to indicate which Resource Block Groups (RBGs) are allocated to UE. A single RBG is a set of consecutive RBs. The allocated RBG do not need to be contiguous.

The number of RBs within an RBG is predetermined and is a function of the channel bandwidth. The following table shows the RBG size as a function of the channel bandwidth: Parameters

Channel Bandwidth 1.4 MHz

3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

Total Number of Resource Blocks

6

15

25

50

75

100

RBG Size (RB)

1

2

2

3

4

4

Number of complete RBG

6

7

12

16

18

25

Size of remaining RBG

-

1

1

2

3

-

Total Number of RBG

6

8

13

17

19

25

Size of bitmap (bits)

6

8

13

17

19

25

Each channel bandwidth includes a number of complete RBG. A partial RBG is also included if the total number of RB is not a multiple of the RBG size.

The bitmap signaled using the Type 0 RB allocation includes a single bit for each RBG. A value of 1 indicates that the RBG has been allocated to UE. The following figure shows the RBG for the channel bandwidth of 5 MHz:

Downlink Resource Allocation Type 1 A type 1 downlink RB allocation can be signaled from eNB to UE using Downlink Control Information (DCI) format 1, 2, and 2A. An allocation received during downlink subframe „n‟ defined the allocated RBs within the same downlink subframe.

Type 1 RB allocations are not applicable to the 1.4 MHz channel bandwidth. Type 1 RB allocations are divided into three sections: oResource Block Group (RBG) subset number oResource Block offset flag oResource Block bitmap


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The RBG sizes are the same as those specified for a Type 0 RB allocation. The number of RBG subsets is equal to the RBG size. The following table shows the RBG size and the number of RBG subsets for each channel bandwidth: Parameters


3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

Total Number of Resource Blocks

N/A

15

25

50

75

100

RBG Size (RB)

N/A

2

2

3

4

4

Number of RBG subsets

N/A

2

2

3

4

4

RBG subset (bits)

N/A

1

1

2

2

2

Offset flag (bits)

N/A

1

1

1

1

1

bitmap (bits)

N/A

6

11

14

16

22

Total Bits

N/A

8

13

17

19

25

The number of bits used to signal the RBG subset is either 1 or 2 depending on the number of subsets. The RBs allocated to UE always belong to a single RBG subset.

The Resource Block offset flag indicates whether the subsequent Resource Block bitmap should be aligned with the bottom of the lowest RB within the subset, or aligned with the top of the highest RB within the subset. This offset is necessary because the bit map is not sufficiently large to include all RBs within the subset. The Resource Allocation Type 1 re-allocation UE and RBG are selected based on the following criteria:

The number of RBG allocated by Resource Allocation Type 0 is one or two RBGs (for example, only short packets can be allocated by RB unit).

UE which is 'required number of RB for Resource Allocation Type 1 < allocated number of RB for Resource Allocation Type 0'.

Downlink Resource Allocation Type 2 A type 2 downlink RB allocation can be signalled from eNB to UE using Downlink Control Information (DCI) format 1A.

An allocation received during downlink subframe „n‟ defined the allocated RBs within the same downlink subframe.

The set of allocated virtual RBs are mapped onto the set of allocated physical RBs.

Contiguous virtual RBs are contiguous both before and after mapping onto their physical RBs. In this case, the set of allocated physical RBs is the same as the set of allocated virtual RBs. In addition, the RB allocation is the same in both time slots belonging to the subframe.


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Contiguous allocations can range from a single virtual RB to the complete set of virtual RBs spanning the entire channel bandwidth.

Contiguous virtual RB allocation is signalled using Resource Indication Values (RIV). The calculation of RIV is the same as when calculating the RIV for type 0 uplink resource allocations.

SYSTEM OPERATION How to Activate The PDSCH resource allocation type is automatically determined by Samsung scheduler based on the DCI format and the traffic type and cannot be directly controlled by the operator. Samsung scheduler determines the PDSCH resource allocation type automatically based on the DCI format and the traffic type. The operator cannot control this.

Key Parameters There is no related parameter.

Counters and KPIs There is no related counter or KPI.

REFERENCE [1] Telefonica, Req20, „The Vendor‟s LTE solution shall support functionality to enquire UE capability and record number of UEs per eNodeB and per cell for each UE category‟, Telefonica RFP („12.04) [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME1503, PUSCH Frequency Hopping INTRODUCTION Uplink resource blocks allocated by type 0 resource allocations are always contiguous. This helps to reduce the peak-to-average ratio of the transmitted signal and consequently improves the transmit power amplifier efficiency. A drawback of contiguous allocation is reduced potential for frequency diversity. Allocating a small number of resource blocks means that the resource allocation spans only a small bandwidth and the propagation channel is relatively well correlated for all resource blocks within the allocation. Allocating a large number of resource blocks increases the potential for frequency diversity because the resource allocation spans a wider bandwidth. Uplink frequency hopping provides frequency diversity while allowing the resource allocations to remain contiguous. This is particularly beneficial to small resource block allocations which do not inherently benefit from frequency diversity. Uplink frequency hopping is applicable to type 0 resource allocations when the frequency hopping flag within DCI format 0 is set to 1. When hopping is used, the resource block allocation field within DCI format 0 includes either 1 or 2 hopping bits. The number of bits is dependent on the channel bandwidth. The value of the hopping bits determines whether type 1 or type 2 hopping is applied. Below table presents the number of hopping bits associated with each channel bandwidth, and their relationship with type 1 and type 2 hopping. Table below outlines hopping bits within the Resource block allocation of DCI format 0. Channel Bandwidth

No of hopping bits

Hopping bit pattern

PUSCH hopping

1.4, 3, 5 MHz

1

0

Type 1

1

Type 2

00

Type 1

10, 15, 20 MHz

2

01 10 11

Type 2

BENEFIT Frequency diversity effects can be exploited and interference can be averaged.

DEPENDENCY Related Radio Technology


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E-UTRAN (LTE). When hopping is used, the resource block allocation field within DCI format 0 includes either 1 or 2 hopping bits. The number of bits is dependent on the channel bandwidth.

LIMITATION Frequency hopping is not applied to type 1 resource allocations, nor to any uplink resource allocation made using DCI format 4.

Samsung eNodeB supports Type2 PUSCH hopping with inter-subframe mode only.

This feature is not supported in indoor pico cells.

SYSTEM IMPACT FEATURE DESCRIPTION The resource mapper maps the complex-valued modulation symbols in sequence on to the physical resource blocks assigned for transmission of PUSCH. In LTE, only localized resource allocation is supported in the uplink due to its robustness to frequency offset compared to distributed resource allocation. Localized resource allocation also retains the single-carrier property in the uplink transmission. As a consequence, there is very little frequency diversity gain. On the contrary, in the downlink it is possible to allocate disjoint sets of resource blocks to a UE to extract some frequency diversity gain. To alleviate this issue, LTE supports frequency hopping on PUSCH, which provides additional frequency diversity gain in the uplink. Frequency hopping can also provide interference averaging when the system is not 100 % loaded.

Type 1 PUSCH Hopping Type 1 hopping divides the channel bandwidth into a fixed number of subbands. Hopping is then supported between those subbands. The number of subbands is fixed by 3GPP and is dependent on the channel bandwidth. The number of subbands associated with each channel bandwidth is presented in below table. This table also presents the maximum number of contiguous resource blocks which can be allocated when using type 1 hopping. Table below outlines number of subbands and Max. contiguous resource blocks for Type 1 hopping. Category

1.4 MHz

3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

Total number of resource blocks

6

15

25

50

75

100

Number of sub-bands

2

2

2

4

4

4

Max. contiguous resource block allocation

2

4

10

10

13

20

Figure below depicts an example for the 5 MHz channel bandwidth. This example eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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assumes that the PUCCH occupies a total of 4 resource blocks per time slots at the upper and lower edges of the channel bandwidth. RRC signaling is used to inform the UE that these resource blocks are not available for hopping. The PUSCH hopping offset (HRBHO) which can be included within an RRC connection reconfiguration message is used for this purpose. The signaled value of the hopping offset is rounded up to an even number if an odd number is sent to the UE.

The example in the figure above assumes that DCI format 0 allocates the UE with 4 resource blocks at the lowest possible position within hopping subband 1. The resource blocks move to the lowest possible position within hopping subband 2 when hopping is applied. The allocated resource blocks are contiguous before and after hopping.

Type 2 PUSCH Hopping Type 2 hopping allows the number of subbands to be configured by the network. The number of subbands can be set to a value between 1 and 4, and is signaled to the UE using RRC signaling, for example, within the PUSCH configuration of an RRC connection reconfiguration message. The maximum number of contiguous resource blocks which can be allocated to a UE is dependent on the channel bandwidth, the number of subbands and the number of resource blocks reserved for the PUCCH. Some example figures are presented in below table. The hopping offset represents the total number of resource blocks reserved for the PUCCH within a time slot. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Table below outlines maximum contiguous allocated resource blocks for type 2 hopping. Category

1.4 MHz

3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

Total Resource blocks

6

15

25

50

75

100

Hopping offset

2

2

2

4

4

4

1 subband

2

4

10

10

13

20

2 subbands

2

4

10

10

13

20

3 subbands

1

4

7

10

13

20

4 subbands

1

3

5

10

13

20

Hopping offset

-

4

4

8

8

8

1 subband

-

4

10

10

13

20

2 subbands

-

4

10

10

13

20

3 subbands

-

3

7

10

13

20

4 subbands

-

5

5

10

13

20

The resource block allocations of {2, 4, 10, 10, 13, 20} appearing in the fourth row of results in table represent the upper limit of the contiguous allocation sizes. These figures decrease as the number of subbnads and as the PUCCH reservation increases. Configuring a single subband represents a special case which generates „mirroring‟ of the resource block allocation around the center of the channel bandwidth. The following figure shows Type 2 hopping with single subband in 5 MHz channel bandwidth (Mirroring).


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Configuring multiple subbands leads to hopping based on predefined hopping patterns. These hopping patterns are defined such that the allocations belonging to different UE do not clash. The function used to generate the hopping pattern is presented in [1]. The results from the hopping pattern function is the allocated physical resource blocks with indexing which starts at 0 just above the lower PUCCH allocation.


How to Activate This section provides the information that you need to configure the feature. Preconditions QCI1 (VoLTE) bearer has been set up for the corresponding UE. Activation Procedure Run CHG-PUSCH-CONF and set PUSCH_HOPPING_ENABLED to enable PUSCH frequency hopping.


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Deactivation Procedure Run CHG-PUSCH-CONF and set PUSCH_HOPPING_ENABLED to disable PUSCH frequency hopping.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Description of CHG-PUSCH-CONF/RTRV-PUSCH-CONF Parameter

Description

PUSCH_HOPPING_ENABLED

PUSCH freq. hopping can be enabled or disabled by this parameter.

Configuration Parameters There are no specific parameters associated with this feature.


REFERENCE [1] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [2] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification


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LTE-ME1504, PUCCH Format INTRODUCTION The amount of control information which a UE can transmit in a subframe depends on the number of SC-FDMA symbols available for transmission of control signaling data (that is, excluding SC-FDMA symbols used for reference signal transmission for coherent detection of the PUCCH). The PUCCH supports different formats depending on the information to be signaled. In this document, PUCCH formats 1, 1A, 1B, 2, 2A, 2B, and 3 will be described.

BENEFIT Minimize the resources needed for transmission of control signalling


Others In FDD, PUCCH format 1b with channel selection and PUCCH format 3 are used only when carrier aggregation is enabled.

LIMITATION None


FEATURE DESCRIPTION The Physical Uplink Control Channel (PUCCH) is used to transfer Uplink Control Information (UCI). UCI can be transferred using the PUSCH.

The release 8 and 9 versions of the 3GPP specifications do not allow an individual UE to transmit both the PUCCH and PUSCH during the same subframe. If a release 8 and 9 UE has application data or RRC signaling to send then UCI is transferred to using the PUSCH. A release 8 and 9 UE transfers UCI using the PUCCH if it does not have any application data nor RRC signaling to transfer.


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In the case of TDD, the PUCCH is not transmitted within the UpPTS field of special subframes.

3GPP TS 36.211 and TS 36.213 specify the 7 PUCCH format presented in below table. PUCCH formats 2a and 2b are not applicable when using the extended cyclic prefix. The information transferred by each PUCCH format is listed in below table. PUCCH format

Number of Bits per Subframe

FDD/TDD

Normal CP

1

-

FDD & TDD

Scheduling Request (SR)

1a

1

FDD & TDD

1 x HARQ-ACK

FDD only

1 x HARQ-ACK + SR

FDD & TDD

2 x HARQ-ACK or 2 x HARQ-ACK + SR

TDD only

Up to 4 x HARQ-ACK with channel selection

1b

2

Extended CP

2

20

FDD & TDD

CSI report

CSI report or CSI report + up to 2 x HARQ-ACK

2a

21

FDD & TDD

CSI report + 1 x HARQACK

Not Applicable

2b

22

FDD & TDD

CSI report + 2 x HARQACK

3

48

FDD

up to 10 x HARQ-ACK, or up to 10 x HARQ-ACK + SR

TDD

up to 20 x HARQ-ACK, or up to 20 x HARQ-ACK + SR

The PUCCH is able to transfer various combinations of Scheduling Requests (SR), Hybrid Automatic Repeat request (HARQ) acknowledgements and Channel State Information (CSI) reports. CSI reports can include Channel Quality Indicators (CQI), Precoding Matrix Indicators (PMI), and Rank Indicators (RI).

In summary, 1) PUCCH formats 1, 1a and 1b transfer HARQ acknowledgements and scheduling requests, 2) PUCCH format 2, 2a and 2b transfer HARQ acknowledgements and CSI reports, and 3) PUCCH format 3 transfers the increased number of HARQ acknowledgements associated with Carrier Aggregation and scheduling request.

When carrier aggregation is used, HARQ acknowledgements of multiple serving cells can be transmitted by using PUCCH format 1b (at most 2 serving cells) or PUCCH format 3. When PUCCH format 1b with channel selection is used, 2 to 4 PUCCH resources are allocated and UE transmits PUCCH format 1b on one of those resources. The modulation scheme and the number of Resource Elements occupied by each PUCCH format are presented in below table. PUCCH Format


Modulation Scheme

1

-

-

Number of Resource Elements Occupied Normal CP


Extended CP

48 + 48 = 96 or 48 + 36 = 84 488

Chapter 6 Radio Scheduler PUCCH Format


Modulation Scheme

Number of Resource Elements Occupied

1a

1

BPSK

1b

2

QPSK

2

20

QPSK

60 + 60 = 120

2a

21

QPSK + BPSK

60 + 60 = 120

2b

22

QPSK + BPSK

3

48

QPSK

Normal CP

Extended CP

Not Applicable

60 + 60 = 120 or 60 + 48 = 108

A single PUCCH transmission always occupies 2 Resource Blocks which are distributed across the 2 time slots belonging to a subframe.

Each pair of resource blocks allocated to the PUCCH can be used simultaneously by multiple UE. The use of different cyclic shifts and different orthogonal spreading codes allows the eNB to differentiate the PUCCH transmissions from multiple UE sharing pair of Resource Blocks.

For 2CC CA, periodic CQI is used in SCell in SLR450, and aperiodic CQI only is used in SCell from SLR500. In Samsung LTE system, the number of PUCCH RBs are semistatically determined according to below tables and the number of UEs. In 3CC CA, PUCCH Format 3 is used for SCell ACK/NACK transmission. System parameter nFormat3RB is used to determine the RB number used for Format3. According the value of nFormat3RB is even or odd, there are two types of 3CC CA resource tables.

If (nFormat3RB mod2) == 0, Option1 table is used. If (nFormat3RB mod2) == 1, Option2 table is used. The purpose to use two types of tables is to maintain the PUCCH RB number be the multiple of 2, no matter the setting value of nFormat3RB is the multiple of 2 or not. TDD-FDD 3CC CA and FDD 3CC CA share the same resource table. Here are the PUCCH resource tables of 3CC CA. Table below outlines 3CC CA, 10 MHz, Option1. StateIdx

Min UE

Max UE

Format1 RB

Format2 RB

Format3 RB

PUCCH RB

Num

Num

Num

Num

0

0

45

3

1

nFormat3RB

4 + nFormat3RB

1

20

140

4

2

nFormat3RB

6 + nFormat3RB

2

90

235

5

3

nFormat3RB

8 + nFormat3RB

3

185

425

5

5

nFormat3RB

10 + nFormat3RB

4

375

600

6

6

nFormat3RB

12 + nFormat3RB


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Table below outlines 3CC CA, 10 MHz, Option2. StateIdx

Min UE

Max UE

Format1 RB

Format2 RB

Format3 RB

PUCCH RB

Num

Num

Num

Num

0

0

100

3

2

nFormat3RB

5 + nFormat3RB

1

50

235

4

3

nFormat3RB

7 + nFormat3RB

2

185

330

5

4

nFormat3RB

9 + nFormat3RB

3

280

425

6

5

nFormat3RB

11 + nFormat3RB

4

375

600

7

6

nFormat3RB

13 + nFormat3RB


Min UE

Max UE

Format1 RB

Format2 RB

Format3 RB

PUCCH RB

Num

Num

Num

Num

0

0

50

3

1

nFormat3RB

4 + nFormat3RB

1

20

235

5

3

nFormat3RB

8 + nFormat3RB

2

185

330

6

4

nFormat3RB

10 + nFormat3RB

3

280

425

7

5

nFormat3RB

12 + nFormat3RB

4

375

600

7

7

nFormat3RB

14 + nFormat3RB


Min UE

Max UE

Format1 RB

Format2 RB

Format3 RB

PUCCH RB

Num

Num

Num

Num

0

0

50

4

1

nFormat3RB

5 + nFormat3RB

1

20

250

5

4

nFormat3RB

9 + nFormat3RB

2

200

350

6

5

nFormat3RB

11 + nFormat3RB

3

300

450

8

7

nFormat3RB

13 + nFormat3RB

4

400

600

8

7

nFormat3RB

15 + nFormat3RB




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Key Parameters This section describes the key parameters for configuration of the feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ULRESCONF-IDLE/RTRV-ULRESCONFIDLE Parameter

Description

CELL_NUM


RESOURCE_TABLE_USAGE

This parameter is used to determine which UL resource table is used, when there are more than one UL resource tables are designed.

START_STATE_IDX

This parameter is the start state index of PUCCH/SRS resource allocation table.

Parameter Descriptions of CHG-PUCCHCONF-IDLE/RTRV-PUCCHCONFIDLE Parameter

Description

CELL_NUM


FORCED_MODE

This parameter is forced mode for changed value. By setting this to True, the corresponding change command can be executed irrespective of the lock status of cell. False: Disable forced mode. Set the value considering the cell status. True: Enable forced mode. Set the value without considering the cell status.

SPS_ACK_USAGE

This parameter determines whether SPS ACK is used or not

CA_CSI_ACK_USAGE

This parameter determines whether additional CSI SCell HARQ-ACK resources for CA is used or not

PUCCH_BLANKING_PRBS

This parameter defines the number of PUCCH PRBs to blank for 15 MHz or 20 MHz BW system.

FORMAT3_ACK_USAGE

This parameter determines whether the HARQ-ACK resources with PUCCH format 3 is used or not

FDD_TDD_N_FORMAT3_RB

For TDD-FDD CA, provides information about the number of resource blocks that are available for use by PUCCH formats 3 transmission in each slot. The sum of fddTddnFormat3RB and fddnFormat3RB should not be larger than 4RB

FDD_N_FORMAT3_RB

For FDD only CA, provides information about the number of resource blocks that are available for use by PUCCH formats 3 transmission in each slot. The sum of fddTddnFormat3RB and fddnFormat3RB should not be larger than 4RB

Counters and KPIs There are no specific counters or Key Performance Indicators(KPIs) associated with this feature.


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REFERENCE [1] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [2] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [3] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME3001, Power Control INTRODUCTION In the uplink, the transmit power of the UE can be adjusted variously through the system parameter setting by physical channel. The UE decides its transmit power through system parameter setting and RSRP measurement. The eNB also can adjust the PUSCH transmit power of UE for various purposes including the purposes of improving the performance of cell throughput, etc., expanding coverage through interference mitigation or guaranteeing a proper reception level to satisfy the specific service. Also eNB can adjust the PUCCH transmit power of UE for satisfy the target SINR which guarantees the stable ACK or CQI reception.

BENEFIT Possible to improve the cell throughput or expanding coverage according to the operating environment through the close-loop power control.

Possible to prevent the unnecessary power consumption of the UE and stabilize the connection to serving eNB.


Others No eNB or UE dependency on this feature

LIMITATION None

SYSTEM IMPACT Coverage Possible to improve the cell throughput or expanding coverage according to the operating environment through the close-loop power control.


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FEATURE DESCRIPTION The transmission power of the UE in the LTE uplink is performed by physical channel including PRACH, SRS, PUSCH, and PUCCH. Herein, PRACH is operated only by the system parameter set without any control of the eNB and SRS is operated in connection with the transmit power of PUSCH. Accordingly, the power control of PUSCH and PUCCH is handled focusing on the role of the eNB.

PUSCH In the LTE uplink, the PUSCH transmission power of the phone is under the following formula as defined in the TS 36.213[1] standard: (1)

Pcmax: The max power of UE (dBm) M_PUSCH (i): No. of PUSCH RBs to transmit in subframe i Po_PUSCH: The target value of reception power of PUSCH (dBm). Po_nominalPUSCH

alpha: A constant deciding the compensation percentage of PL PL: The downlink pathloss measured by the phone (dB) f(i): The accumulated or absolute value of TPC command received from the base station The LTE uplink power control may be largely divided into open-loop power control and closed-loop power control and the main features are as shown below. Open-loop power control (OLPC) In the LTE uplink, the UE decides the initial transmission power according to the OLPC and changes the transmission power according to TPC power control obtained from the eNB. In the OLPC eNB does not determine the target SINR for each UE. The UE decides transmission power according to formula (1) by estimate the pathloss between the eNB and the UE, which is obtained by using the difference between the transmission power and reception power of the Reference Signal (RS). The transmission power of RS can be identified through SIB, a broadcast message transmitted from the eNB. In short, the value reflected to the transmission power of the uplink is based on the pathloss of the downlink. And this pathloss may not be fully compensated according to the alpha value of Formula (1). In the specifications, eight values including 0, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 are defined. If the alpha is 0, no pathloss is compensated and if it is 1, pathloss is fully compensated. If all pathlosses are compensated, unless the UE has the lack of the power, the signals of all phones received at the eNB have the same intensity (without fading or in the long term perspective). If partial compensation is applied, it is possible to mitigate interference between cells by reducing the transmission power of the UE in the cell edge area. Also partial compensation increases the SINR of the UE in the cell-center area relatively higher than the SINR in the cell-middle or cell-edge areas. Accordingly, this has the advantage to increase cell throughputs.


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Closed loop power control(CLPC) In the LTE, the eNB can control the transmission power of the UE by transmitting the TPC (transmit power control) command. The TPC command can be transmitted to the UE through PDCCH DCI format 0, 3 or 3A, and the UE reflects the received TPC command value to the f (i) of Formula (1). The TPC command value received from the eNB may be applied by accumulating the received value in accumulated mode or the received absolute value in absolute mode. The method for controlling the uplink transmission power of the UE from the eNB is called Closed Loop Power Control (CLPC) and the main purposes are as follows:

Maximization of the cell throughput: Throughput maximization means TBS(Transport Block Size) maximization for each TTI, and this TBS is decided by the combination of number of RB and MCS as in the specifications. RB size and MCS are affected by PUSCH power control. For example, if a transmit power per RB increases, available number of RB reduces but MCS may increase. In contrast, if transmit power per RB decreases, available number of RB increases but MCS may decrease. The UL scheduler will maximize TBS size based on available power and buffer condition of the UE which can be obtained from PHR(power headroom report) and the BSR(buffer status report), respectively. UL scheduler will determine possible combinations of PRB size and MCS based on TBS table, and adjust the transmit power to achieve the maximum TBS. This functionality is applied to the UEs with large non-GBR buffer size.

Inter-cell interference reduction: UL scheduler determines the dominant interfering UEs to neighbor cells and decreases their transmit power. This functionality mitigates the inter-cell interference, thus it increases the cell-edge UE‟s performance and expands the cell-coverage in interference-limited network environment. It is applied to all nonGBR service UEs regardless of buffer size. VoLTE service UE is excluded this functionality to preserve the service quality. oGuarantee of properly received SINR: If the UE has unnecessarily high transmission power and received SINR exceeds the required SINR of the maximum MCS, eNB decreases the UE's transmission power. Or if it fails to satisfy the required SINR based on the minimum MCS or the target MCS of the specific service, the transmission power of the UE is increased for stable reception of PUSCH.

PUCCH The purpose of the power control of PUCCH channel is to guarantee the stabilized reception of each PUCCH format that is transmitted by the phone. The output power of PUCCH of the phone is decided as follows under the TS 36.213[1] standard:

Pcmax: The max power of UE (dBm) h(n_CQI, n_HARQ): number of information bit for CQI or HARQ. Po_PUCCH: The target value of reception power of PUSCH (dBm). Po_nominalPUSCH. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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PL: The downlink pathloss measured by the phone (dB) delta_F: The transmission power offset values of other formats compared to the PUCCH format 1a standard.

g(i): The accumulated value of the TPC command received from the base station. Differently from PUSCH, PUCCH compensates all pathlosses measured by the phone and the number of RB is also set to be 1. In addition, the transmission power is decided depending on the number of transmission information bits. The eNB transmits the TPC command to the UE to make the received SINR close to target SINR. The TPC command for PUCCH is transmitted to the UE through the DL grant.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure PUCCH power control is basically enabled and cannot be disabled by operator. Operator can choose whether to use open loop power control or closed loop power control for PUSCH. To activate the OLPC for PUSCH, do the following:

Run CHG-ULPWR-CTRL and set accumulationEnabled to 0 (FALSE). To activate the CLPC for PUSCH, do the following:

Run CHG-ULPWR-CTRL, and then set accumulationEnabled to 1 (FALSE). Deactivation Procedure PUCCH power control is basically enabled and cannot be disabled by operator.

PUSCH power control is basically enabled and operator can choose whether to use OLPC or CLPC.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of this feature. Activation/Deactivation Parameters There is no parameter for activate or deactivate this feature.


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Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Table below outlines related commands. Command

Description

CHG-PWR-PARA

Changes the configuration required to operate the Uplink Power Control in the eNB. The alpha value used in PUSCH Power Control, transmission power settings by PUCCH format, settings for the p0_nominal_PUCCH and p0_nominal_PUSCH etc can be changed.

RTRV-PWR-PARA

Retrieves the configuration information on the Uplink Power Control in the eNB. The information retrieved includes the alpha value used in PUSCH Power Control, transmission power settings by PUCCH format, settings for the p0_nominal_PUCCH and p0_nominal_PUSCH etc.

Table below outlines related parameters. Parameter

Description

cellNum

The cell number. This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity system is 1 FA/3 Sector, up to 3 cells are supported.

p0NominalPUSCH

PUSCH Initial Power value. p0NominalPUSCH value is used in PUSCH power control and provided from higher layers.This field is applicable for non-persistent scheduling, only.

alpha

Pathloss compensation factor for PUSCH/SRS transmit power of UE. al0 corresponds to 0, al04 to 0.4 and so on.

p0NominalPUCCH

PUCCH Initial Power value. p0Nominal PUCCH value is used in PUCCH power control and provided from higher layers.

deltaFPUCCHFormat1

The PUCCH format 1 transmits power offset comparing to that of PUCCH format1a. deltaF_2 corresponds to -2 dB, deltaF0 to 0 dB and deltaF2 to 2 dB, respectively.

deltaFPUCCHFormat1b

The PUCCH format 1b transmits power offset comparing to that of PUCCH format1a. deltaF1 corresponds to 1 dB, deltaF3 to 3 dB and deltaF5 to 5 dB, respectively.

deltaFPUCCHFormat2

The PUCCH format2 transmitspower offset comparing to that of PUCCH format1a. deltaF_2 corresponds to -2 dB, deltaF0 to 0 dB, deltaF1 to 1 dB and deltaF2 to 2 dB, respectively.

deltaFPUCCHFormat2a

The PUCCH format2a transmits power offset comparing to that of PUCCH format1a. deltaF_2 corresponds to -2 dB, deltaF0 to 0 dB and deltaF2 to 2 dB, respectively.

deltaFPUCCHFormat2b

The PUCCH format2b transmits power offset comparing to that of PUCCH format1a. deltaF_2 corresponds to -2 dB, deltaF0 to 0 dB and deltaF2 to 2 dB, respectively.

deltaPreambleMsg3

Msg3 transmits power offset comparing to preamble initial target power(preambleInitialReceivedTargetPower in 3GPP TS 36.331). Actual value = IE value*2 (dB)

deltaFPUCCHFormat3

The PUCCH format 3 transmits power offset comparing to that of PUCCH format1a. deltaF_1 corresponds to -1 dB, deltaF0 to 0 dB and deltaF1 to 1 dB, and so on, respectively.

deltaFPUCCHFormat1bCS

The PUCCH format 1b with channel selection transmits power offset comparing to that of PUCCH format1a. deltaF1 corresponds to 1 dB, deltaF2 to 2 dB, respectively.


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Description

IotReductionSinrMargin

PUSCH SINR margin for IoT reduction operation in UL power control. Higher value allows higher target SINR (unit: 0.1 dB)

Table below outlines related commands. Command

Description

CHG-ULPWR-CTRL

Changes the configuration required to operate dedicated Uplink Power Control. The p0 value per UE for PUSCH/PUCCH, whether the accumulation mode is used by TPC, the power offsets of PUSCH and SRS, and the L3 filtering coefficient value used by the UE to calculate a path loss can be changed.

RTRV-ULPWR-CTRL

Retrieves the configuration information required to operate dedicated Uplink Power Control. The information retrieved includes p0 value per UE for PUSCH/PUCCH, information on whether the accumulation mode is used by TPC, power offsets of PUSCH and SRS, and the L3 filtering coefficient value used by UE to calculate path.

Table below outlines related parameters. Parameter

Description

cellNum


p0UePUSCH

The non-persistent scheduling P0 value used in PUSCH power control, which is determined per UE. See 3GPP TS 36.213 [23, 5.1.1.1], unit dB. This field is applicable for non-persistent scheduling, only.

deltaMCSenabled

Whether to use a power offset against other MCSs. ci_en0: 0. ci_en1: 1.25. Refer to 5.1 of 3GPP TS 36.213.

accumulationEnabled

Whether to use the accumulation mode and absolute mode in the TPC. 0: Accumulation mode is not used. 1: Accumulation mode is used.

p0UePUCCH

P0 value used in PUCCH power control, which is determined per UE.

pSRSoffset

The power offset value between PUSCH and SRS. Parameter for periodic and a periodic sounding reference signal transmission respectively. See 3GPP TS 36.213 [23, 5.1.3.1]. For Ks = 1.25, the actual parameter value is pSRS-Offset value-3. For Ks = 0, the actual parameter value is -10.5 + 1.5 * pSRS-Offset value.

filterCoefficient

Filtering coefficient used to measure RSRP in order to calculate a path loss.


REFERENCE [1] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[2] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification [3] 3GPP TS 36.101 Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception


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LTE-ME3002, Residual BLER aware UL Power Control INTRODUCTION The uplink performance degradation can happen from the cell in high interference condition during the initial attach or handover. This feature presents the power control operation for the uplink performance stabilization for UEs which suffer from low SINR and residual error caused by the interference increment.

BENEFIT Improve the degraded quality of service (QOS) including VoLTE rapidly Improve the statistics representing the performance in weak channel condition such as the Call failure rate, Call drop rate, and etc.

DEPENDENCY No HW or UE dependency

LIMITATION None

SYSTEM IMPACT FEATURE DESCRIPTION The existing power control operation is performed when receiving PHR (power headroom report) from UEs. However in case of sudden strong interference the uplink performance is much degraded and thus residual BLER occurs frequently. PHR reception is not guaranteed or it can be delayed. Therefore it can take a long time to recover the uplink SINR by increasing the transmit power. This feature performs the following operations to increase the SINR rapidly without PHR reception. If UE‟s received SINR is poor and the Residual error occurs frequently, UL scheduler generates the power up TPC command in the next UL grant(DCI format 0) in order to increase the PUSCH transmission power of the relevant UE. Operator can configure whether to increase +1dB or +3dB. However in case the transmission power of the relevant UE already reaches Pmax, power up TPC command can be neglected Therefore, UL scheduler also reduces the allocation RB size in the next UL grant to increase the SINR. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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How to Activate This section provides the information that you need to configure the feature. Preconditions AccumulationEnabled in CHG-ULPWR-CTRL is needed to be 1(enabled). Activation Procedure To activate this feature, do the following:

Run CHG-PWR-PARA, and then set RerrorTpcUpCmd to 1 or 2. oIf set to 1, the scheduler sends TPC command as 2(+1dB) in UL grant. oIf set to 2, the scheduler sends TPC command as 3(+3dB) in UL grant. Deactivation Procedure To deactivate this feature, do the following: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Run CHG-PWR-PARA, and then set RerrorTpcUpCmd to 0.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of this feature. Activation/Deactivation Parameters To activate or deactivate this feature, run the associated commands and set the key parameters. Related commands Command

Description

CHG-PWR-PARA

Changes the configuration required to operate the Uplink Power Control in the eNB.

RTRV-PWR-PARA

Retrieves the configuration information on the Uplink Power Control in the eNB.

Related parameters Parameter

Description

RerrorTpcUpCmd

This parameter generates the PUSCH TPC up command if residual error occurs and PUSCH SINR is poor. Generated TPC command will be sent in the next UL grant(DCI format 0) with reduced allocated RB size assignment. 0: OFF 1: ON with TPC +1dB 2: ON with TPC +3dB

Configuration Parameters No more configuration parameters in this feature. TPC command value also can be configurable by RerrorTpcUpCmd.


REFERENCE [1] 3GPP TS 36.213 (Physical layer procedures), section 5.1.1


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LTE-ME3005, DL Power Allocation INTRODUCTION Unlike the uplink power control, there is no explicit feedback from the UEs to control the eNB transmit power for the downlink power control, The power levels for dedicated control channels such as PDCCH and PHICH can be determined based on downlink channel quality feedback from the UEs. The downlink channel quality feedback is provided by the UEs to support channel sensitive scheduling in the downlink. Therefore, the downlink transmit power control is fundamentally a power allocation scheme rather than a power control scheme. Since the control channel transmissions are spread over the whole system bandwidth, wideband channel quality information is used to determine the power levels for these control channels. It should be noted that various channel quality feedback formats are supported and wideband channel quality is always present in all the feedback formats to enable power control for the downlink control channels. The downlink power control determines the Energy Per Resource Element (EPRE) prior to cyclic prefix insertion. The EPRE also denotes the average energy taken over all constellation points for the modulation scheme applied. The eNB determines the downlink transmit energy per resource element. A UE may assume the downlink reference symbol EPRE is constant across the downlink system bandwidth and constant across all subframes until different reference signal power information is received.

BENEFIT Optimized downlink power allocation will have an impact on the performance of an LTE UE

DEPENDENCY None

LIMITATION None

SYSTEM IMPACT Performance and Capacity This feature can change the throughput performance of the cell edge user.


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FEATURE DESCRIPTION The eNB determines the downlink transmit energy per resource element. A UE may assume downlink cell-specific Reference Signal (RS) EPRE is constant across the downlink system bandwidth and constant across all subframes until different cell-specific RS power information is received. The downlink cell-specific reference-signal EPRE can be derived from the downlink reference-signal transmit power given by the parameter referenceSignalPower provided by higher layers. The downlink reference-signal transmit power is defined as the linear average over the power contributions (in [W]) of all resource elements that carry cell-specific reference signals within the operating system bandwidth. The ratio of PDSCH EPRE to cell-specific RS EPRE among PDSCH REs for each OFDM symbol is denoted by either ρA or ρB according to the OFDM symbol index as given by below table. Below table is OFDM symbol indices within a slot of a non-MBSFN subframe where the ratio of the corresponding PDSCH EPRE to the cell-specific RS EPRE is denoted ρA or ρB. Number of antenna ports

OFDM symbol indices within a slot where the ratio of the corresponding PDSCH EPRE to the cell-specific RS EPRE is denoted by ρA

OFDM symbol indices within a slot where the ratio of the corresponding PDSCH EPRE to the cell-specific RS EPRE is denoted by ρB

Normal cyclic prefix

Extended cyclic prefix

Normal cyclic prefix

Extended cyclic prefix

One or two

1, 2, 3, 5, 6

1, 2, 4, 5

0, 4

0, 3

Four

2, 3, 5, 6

2, 4, 5

0, 1, 4

0, 1, 3

For a UE in transmission mode 8 when UE-specific RSs are not present in the Physical Resource Blocks (PRB) upon which the corresponding PDSCH is mapped or in transmission modes 1-7, the UE may assume that for 16 QAM, 64 QAM, spatial multiplexing with more than one layer or for PDSCH transmissions associated with the multi-user MIMO transmission scheme,

ρA is equal to δpower-offset + PA + 10log10 (2) [dB] when the UE receives a PDSCH data transmission using precoding for transmit diversity with 4 cellspecific antenna ports according to Section 6.3.4.3 of [1]

ρAis equal to δpower-offset + PA [dB] otherwise where, δpower-offset is 0 dB for all PDSCH transmission schemes except multiuser MIMO and where PA is a UE specific parameter provided by higher layers. The cell-specific ratio is given by below table. according to cell specific parameter signalled by higher layers and the number of configured eNB cell specific antenna ports.

The cell-specific ratio ρB/ρA for 1, 2, or 4 cell specific antenna ports. PB

ρB/ρA One Antenna Port

Two and Four Antenna Ports

0

1

5/4

1

4/5

1


504

Chapter 6 Radio Scheduler PB

ρB/ρA One Antenna Port

Two and Four Antenna Ports

2

3/5

3/4

3

2/5

1/2


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure/Deactivation Procedure DL Power allocation This feature is basically enabled. Therefore, it does not require addition activation process for this feature. Change this parameter value while the eNB is not operating. Changing the parameter value while the eNB is operating requires special care because it may cause abnormal operation. The change should be performed as follows:

1 Change the FORCED_MODE value from False to True. 2 Change the parameter value and block the cell. And unblock the cell again. Changing the parameter value while the eNB is operating requires special care because it may cause abnormal operation. After change the parameter value, block the cell and unblock it. Otherwise, the eNB may work abnormally. PDSCH power boosting To Activate PDSCH power boosting, dlPdschPowerBoostFlag should be set 1. To deactivate PDSCH power boosting, dlPdschPowerBoostFlag should be set 0.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters DL Power allocation This feature is basically enabled. There is no activation/deactivation parameters. PDSCH power boosting eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Activation/Deactivation parameter is dlPdschPowerBoostFlag. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. DL Power allocation Parameter Descriptions of RTRV-PDSCH-IDLE/CHG-PDSCH-IDLE Parameter

Description

CELL_NUM


DL_POWER_OPTION

This parameter secifies the power setting option. The power of the RS per resource grid is set to a multiple of the power of the data per resource grid. The power of the RS per resource grid is set to a multiple of the power of the data per resource grid. option0: The power of the RS per resource grid is the same as that of the data per resource grid. option1: The power of the RS per resource grid is one and a half times as much as that of the data per resource grid. option2: The power of the RS per resource grid is two times as much as that of the data per resource grid. option3: The power of the RS per resource grid is a half times as much as that of the data per resource grid. option4: The power of the RS per resource grid is 0.4 times as much as that of the data per resource grid. option5: The power of the RS per resource grid is 0.33 times as much as that of the data per resource grid. option6: The power of the RS per resource grid is 0.32 times as much as that of the data per resource grid. option7: The power of the RS per resource grid is 0.25 times as much as that of the data per resource grid. option8: The power of the RS per resource grid is 0.2 times as much as that of the data per resource grid. option9: The power of the RS per resource grid is 0.16 times as much as that of the data per resource grid. option10: The power of the RS per resource grid is 0.13 times as much as that of the data per resource grid. Change this parameter value while the eNB is not operating. Changing the parameter value while the eNB is operating requires special care because it may cause abnormal operation. The change should be performed as follows: 1Change the FORCED_MODE value from False to True. 2Change the parameter value and block the cell. And unblock the cell again. Changing the parameter value while the eNB is operating requires special care because it may cause abnormal operation. After change the parameter value, block the cell and unblock it. Otherwise, the eNB may work abnormally.

FORCED_MODE

This parameter indicates whether to change the configuration regardless of the cell status.


506


Description False: It can be used when the cell status is LOCK state. True: It can be changed regardless of the cell status.

PDSCH power boosting Parameter Descriptions of RTRV-PDSCHPWR-PARA/CHG-PDSCHPWR-PARA Parameter

Description

dlPdschPowerBoostFlag

PDSCH Power Boosting support flag. 0(FALSE): Not support 1(TRUE): Support


REFERENCE [1] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME3101, HARQ in DL and UL INTRODUCTION HARQ is used for facilitating fast error detection and correction. HARQ is a stop and wait protocol; subsequent transmission can take place only after receiving ACK/NACK from the receiving entity. In case an ACK is received a new transmission is done else a retransmission is done. This scheme can be improved by using multiple channels for supporting HARQ service. In LTE, HARQ is implemented as MAC level (L2) module called HARQ entity. HARQ entity is associated with N HARQ processes to implement N stop and wait HARQ protocol

BENEFIT Achieve reliable data transmission by sending a message of ACK/NACK.

DEPENDENCY None

LIMITATION None

SYSTEM IMPACT HARQ in DL and UL is required for normal LTE operation based on 3GPP Rel-8. Multiplexing mode which is supported in Jio PKG 6.0 can enhance a UE throughput than Bundling mode when transmission rank of the UE is 1

Operator can select TTI bundling on/off by parameter 'TTI_BUNDLING'. Operator can select TDD HARQ Ack/Nack feedback mode by parameter 'TDD_ACK_NACK_FEEDBACK_MODE'.

Operator can select maximum number of HARQ transmission by parameter 'MAX_HARQTX'.


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FEATURE DESCRIPTION Scheduling HARQ In the downlink, HARQ is asynchronous and the schedule for HARQ transmissions is not predeclared to the UEs. When the HARQ blocks are transmitted they need to be accompanied by control information such as HARQ process ID, new transmission/retransmission. This scheme has following advantages:

Complete flexibility of scheduling different data flows as per their respective priorities

In case of frequency selective fading, link adaptation is possible. As the resources for HARQ processes are not predetermined, the blocks (new transmission/retransmission) can be modulated and coded as per the link conditions. In uplink the HARQ transmission is synchronous, which means that the HARQ blocks are predetermined for transmission and retransmission. The modulation, coding scheme for the blocks is predetermined by the eNB. Thus, for uplink transmission, there is no need for transmitting control information along with the HARQ data blocks. The modulation and coding scheme for the different UEs may be tuned by the eNB based on the reports submitted by the UEs.

HARQ in downlink The downlink HARQ transmission is asynchronous; the UE receives the information about HARQ transmissions on control channel. Downlink assignments and HARQ information is transmitted on PDCCH and the TB (transport blocks) are transmitted on DL-SCH. HARQ entity in UE deciphers the HARQ information. HARQ information consists of parameters such as HARQ process ID, New Data Indicator (NDI), Redundancy Version (RV), Transport Block (TB) size. HARQ entity maintains a number of HARQ processes, HARQ information and TB is forwarded by HARQ entity to relevant process. A transmission is considered new transmission in case

This is first transmission ever received for this process ID or NDI has toggled in HARQ information. Otherwise TB is considered retransmitted. For a new transmission, HARQ process replaces the old contents of associated HARQ buffer with the new contents. If the decoding of this data block is successful the data is handed over to disassembly and demultiplexing MAC module. If decoding fails, data is preserved in this buffer. For retransmission, the retransmitted data is soft combined with old buffer contents.


509


HARQ process decodes the new contents; if the decoding is successful the retransmitted block is handed over to disassembly and demultiplexing unit. It may happen that the retransmission is done using some different coding scheme and the TB is of different size, in this case soft combining is not possible and HARQ buffer contents are replaced with the new received buffer contents. HARQ process generates a positive ACK for the successfully decoded data and negative ACK for the unsuccessful ones. HARQ feedback has a lower priority than measurement gaps. HARQ feedback is transmitted when measurement gaps are not scheduled.

HARQ in uplink Uplink HARQ is synchronous; UE receives the Uplink grant for transmission on control channel. The grant indicates control information such as HARQ process ID, type of transmission (new/retransmission), redundancy version. Downlink ACK/NACK are sent on PHICH and uplink grants are sent via PDCCH. If a PDCCH grant is received, data is considered ack/nack based on HARQ info. HARQ feedback is not considered in this case. In case PDCCH is not received, HARQ feedback is considered. In case NACK is received-non-adaptive retransmission is planned. In case ACK is received, no non-adaptive retransmission can be planned. HARQ buffer is preserved as-is. (till PDCCH grant indicative of ACK arrives) On receiving PDCCH grant for new transmission, HARQ entity receives a PDU for transmission from „Multiplexing and assembly‟ module. HARQ entity delivers the PDU, uplink grant and HARQ info to HARQ process (that was indicated in control information) and instructs the HARQ process to transmit the new block. The HARQ process stores the received PDU in its HARQ buffer and sets the redundancy version IRV indicated in control information. HARQ process then instructs the PHY layer to transmit the block. On receiving the PDCCH grant for retransmission, HARQ entity delivers uplink grant and HARQ info to relevant HARQ process and instructs it to generate an adaptive retransmission. HARQ process instructs PHY to retransmit the buffer contents as per the redundancy version instructed by eNB in control information. If max limit for retransmissions is reached HARQ process flushes the contents of buffer.

HARQ ARQ Interaction ARQ uses the knowledge from HARQ about transmission status of a MAC PDU. This interaction is useful in handling HARQ residual error cases. HARQ provides indications to ARQ block when:

HARQ transmitter reaches maximum retransmissions for a TB without getting an ACK

HARQ receiver is able to detect a transmission failure First indication is called as NACK1 and the second one is called NACK2. We discuss the two conditions in detail in following sections.


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NACK 1 This situation may be caused when HARQ block transmissions could not be successfully decoded at receiver. After reaching max limit for number of retransmission MAC sends NACK1 indication to RLC layer. On getting this indication ARQ block in RLC can recode/re-segment the block for transmission. Max number of retransmission in Uplink should be known to the eNB, as eNB has to stop scheduling retransmissions after UE has reached the max transmissions. Maximum number of retransmission suited for a connection depends on the type of QoS. For a real time traffic flow, more than 1-2 retransmissions may be unnecessary. However, for a file transfer kind of flow it would be useful to have greater number of retransmissions. This radio bearer specific max limit has to be indicted in UE reports to eNB. However, the scheme is prone to failure in case UE reports are received late/erroneously at eNB. The other option is to have a common limit for max retransmissions for all the radio bearers. Generation of NACK1 from MAC to RLC may also be caused if an ACK from receiver is misinterpreted as NACK. This misinterpretation leads to unnecessary retransmissions.

NACK 2 When HARQ receiver transmits NACK for a HARQ block, it expects the block to be retransmitted. If the receiver sees no transmission in the expected TTI or when the receiver sees the HARQ process ID rescheduled for a new transmission; the receiver knows that the NACK has been misinterpreted as ACK by the transmitter. MAC indicates this to RLC and RLC sends a control message to peer to indicate the missing block. The scheme requires a request for resource grant for UE and eNB followed by transmission of control message. Synchronous HARQ was adopted in uplink to save on control channel resources and this control messaging becomes overhead. This NACK2 interaction provides little performance gain compared to added complexity and has been dropped from recent versions of specifications.



Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature


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Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-TRCH-INF/CHG-TRCH-INF Parameter

Description

CELL_NUM


TTI_BUNDLING

This parameter is used to enable to use TTI bundling. False: TTI bundling is not used. True: TTI bundling is used.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-TRCH-INF/CHG-TRCH-INF Parameter

Description

CELL_NUM


MAX_HARQTX

The maximum HARQ Tx per cell. The UE executes PUSCH retransmission in accordance with this parameter value.

MAX_HARQTX_BUNDLING

The maximum HARQ transmission count is sub-frame bundling mode.

Parameter Descriptions of RTRV-PUCCHCONF-IDLE/CHG-PUCCHCONFIDLE Parameter

Description

CELL_NUM


TDD_ACK_NACK_FEEDB ACK_MODE

Parameter indicates one of the two TDD ACK/NACK feedback modes.(bundling, multiplexing) 0: Bundling mode. 1: Multiplexing mode.


REFERENCE [1] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[3] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification [4] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification


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LTE-ME3201, Basic Link Adaptation INTRODUCTION The principle of link adaptation depends on the radio interface design, which is efficient for packet-switched data traffic. Unlike the early versions of UMTS, which used fast closed-loop power control to support circuit-switched services with a constant data rate, link adaptation in HSPA and LTE adjust the transmitted information data rate dynamically to match the prevailing radio channel capacity for each user. For the downlink data transmissions in LTE, the eNB typically selects the modulation scheme and code rate depending on a prediction of the downlink channel conditions. An important input to this selection process is the Channel Quality Indicator (CQI) feedback transmitted by the UE in uplink. The CQI feedback is an indication of the data rate, which can be supported by the channel, by considering Signal to Interference plus Noise Ratio (SINR) and the characteristics of the UE receiver. For the LTE uplink transmissions, the link adaptation process is similar to the downlink, with the selection of modulation and coding schemes also being under the control of eNB. An identical channel coding structure is used for uplink, while the modulation scheme can be selected between QPSK and 16 QAM. For the highest category of UE, the modulation can also be 64 QAM. The main difference from downlink is that instead of basing the link adaptation on CQI feedback, the eNB can directly make its own estimate of the supportable uplink data rate.

BENEFIT Match the transmission parameter, such as Modulation and Coding Scheme (MCS) and MIMO transmission rank, and precoding to the channel condition on resource allocated by the scheduler.

Serve the best resource allocation under the restriction of limited resource pool.

DEPENDENCY AND LIMITATION Dependency To support uplink 64 QAM, category 5 UE is prerequisite.


Adaptive Modulation and Coding (AMC) CQI Feedback eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Adaptive Modulation and Coding In cellular communication systems, the quality of the signal received by the UE depends on the channel quality from the serving cell, the level of interference from other cells, and the noise level. To optimize system capacity and coverage for a given transmission power, the transmitter tries to match the information data rate for each user to the variations in received signal quality. This is commonly referred to as link adaptation and is typically based on AMC. The degrees of freedom for AMC consist of the modulation and coding schemes:

Modulation Scheme: Low-order modulation, that is, few data bits per modulated symbol, for example, QPSK, is more robust, and can tolerate higher levels of interference. However, provides a lower transmission bit rate. High-order modulation, that is, more bits per modulated symbol, for example, 64AQM, offers a higher bit rate. However, is more prone to errors due to the higher sensitivity to interference, noise, and channel estimation errors. Therefore, this is useful only when SINR is sufficiently high.

Code rate: For a given modulation, the code rate can be selected depending on the radio link conditions. A lower code rate can be used in poor channel conditions and a higher code rate in the case of high SINR. The adaptation of the code rate is achieved by applying puncturing or repetition to the output of a main code. A key issue in the design of the AMC scheme for LTE was whether:

All Resource Blocks (RBs) allocated to one user in a subframe should use the same Modulation and Coding Scheme (MCS).

MCS should be frequency dependent within each subframe. A small throughput improvement arises from a frequency-dependent MCS compared to a frequency-independent MCS in the absence of frequency selective transmission power control. Therefore, the additional control signaling overhead associated with frequency-dependent MCS is not justified. In LTE, the modulation and channel coding rates are constant over the allocated frequency resources for a given user, and time-domain channel-dependent scheduling and AMC are supported instead. In LTE, the UE can be configured to report CQIs to assist eNB for selecting an appropriate MCS to be use in the downlink transmissions. The CQI reports are derived from the downlink received signal quality, based on measurements of the downlink Reference Signals (RS). The reported CQI is not a direct indication of SINR in LTE. Instead, the UE reports the highest MCS that it can decode with a transport block error rate probability not exceeding 10 %. Thus, the information received by eNB considers the characteristics of the UE receiver, and not just the prevailing radio channel quality. Hence, the UE that is designed with advanced signal processing algorithms, for example, using interference cancellation techniques, can report a higher CQI even in the same channel quality. Depending on the characteristics of the eNB scheduler, a higher data rate can be received. Table below lists the modulation schemes and code rates, which can be signalled by means of a CQI value. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The AMC can exploit the UE feedback by assuming that the channel fading is sufficiently slow. This requires the channel coherence time to be at least as long as the time between the UE measurements of the downlink reference signals and the subframe containing the correspondingly-adapted downlink transmission on the PDSCH. However, a trade-off exists between the amount of CQI information reported by UEs and the accuracy with which AMC can match the prevailing conditions. Frequent reporting of CQI in the time domain allows better matching to the channel and interference variations. Wherein, fine resolution in the frequency domain allows better exploitation of frequency-domain scheduling. However, both lead to increased feedback overhead in the uplink. Therefore, the eNB can configure both the time-domain update rate and the frequency-domain resolution of the CQI.

CQI Feedback The periodicity and frequency resolution to be used by the UE to report CQI are both controlled by the eNB. In the time domain, both periodic and aperiodic CQIs reporting are supported. The PUCCH is used for periodic CQI reporting only. The PUSCH is used for aperiodic reporting of CQI, where the eNB specifically instructs the UE to send an individual CQI report embedded into a resource which is scheduled for uplink data transmission. The frequency granularity of the CQI reporting is determined by defining a number of sub-bands. The CQI reporting modes can be wideband CQI, higher layer configured sub-band reporting, or UE-selected sub-band reporting. In case of multiple transmit antennas at eNB, CQI value can be reported for the second codeword. For some downlink transmission modes, additional feedback signalling consisting of Precoding Matrix Indicators (PMI) and Rank Indications (RI) is also transmitted by the UE.


516


Types of CQI Report Mode Wideband reporting: The UE reports one wideband CQI value for the whole system bandwidth.

Higher layer configured sub-band reporting: The UE reports a wideband CQI value for the whole system bandwidth. In addition, the UE reports a CQI value for each sub-band, calculated assuming transmission only in the relevant subband. The sub-band CQI reports are encoded differentially with respect to the wideband CQI using 2-bits as: Sub-band differential CQI offset = Sub-band CQI index-Wideband CQI index. Table below outlines the sub-band size and the number of sub-bands for the configured higher layer reporting. Channel Bandwidth

Resource Blocks

Subband Size (RBs)

Number of Subbands

1.4 MHz

6

Not Applicable

Not Applicable

3 MHz

15

4

4

5 MHz

25

4

7

10 MHz

50

6

9

15 MHz

75

8

10

20 MHz

100

8

13

UE-selected sub-band reporting: The UE selects a set of M preferred subbands of size k within the whole system bandwidth. The UE reports one wideband CQI value and one CQI value reflecting the average quality of M selected subbands. The CQI value for the M selected subbands for each codeword is encoded differentially using 2-bits relative to its respective wideband CQI as defined by Differential CQI = CQI Index for average of M preferred sub-bands Wideband CQI index. Table below outlines the sub-band size k and the number of preferred sub-bands (M) versus downlink system bandwidth for aperiodic CQI reports for the UE-selected sub-bands feedback: Channel Bandwidth

Resource Blocks

Subband Size (RBs)

Number of Preferred Subbands (M)

1.4 MHz

6

Not Applicable

Not Applicable

3 MHz

15

2

3

5 MHz

25

2

3

10 MHz

50

3

5

15 MHz

75

4

6

20 MHz

100

4

6

In UE-selected subband reporting, UE should report average CQI of M number of preferred subband in addition to wideband CQI. Fundamentally UE-selected subband reporting has relatively small amount channel quality information compared to higher layer configured subband reporting which mandates UE to report all the individual channel quality of all subbands. Because of this reason, Samsung eNB supports wideband CQI reporting mode and higher layer configured subband CQI reporting mode.


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Periodic and Aperiodic CQI Report Mode Periodic CQI: If the eNB wants to receive the periodic reporting of CQI, the UE transmits the reports using PUCCH. Only wideband and UE-selected sub-band feedback is possible for periodic CQI reporting, for all downlink (PDSCH) transmission modes. As with the aperiodic CQI reporting, the type of periodic reporting is configured in eNB by the RRC signalling. In contrast to aperiodic reporting, the reporting mode is not signalled explicitly. Instead, the eNB signals type of reporting and transmission mode. For the wideband periodic CQI reporting, the period can be configured to {2, 5, 10, 16, 20, 32, 40, 64, 80, 160} ms or Off. While the wideband feedback mode is similar to the sent via PUSCH, UE selected sub-band CQI using PUCCH is different. In this case, the total number of sub-bands, N, is divided into J fractions called bandwidth parts. The value of J depends on the system bandwidth as summarized in the table below. In case of periodic UE-selected sub-band, for CQI reporting, one CQI value is computed and reported for a single selected sub-band from each bandwidth part, along with the corresponding sub-band index. Table below outlines the periodic CQI reporting with UE-selected sub-bands, sub-band size (k), and bandwidth parts (J) versus downlink system bandwidth. Channel Bandwidth

Resource Blocks

Subband Size (RBs)

Number of Preferred Subbands (M)

1.4 MHz

6

Not Applicable

Not Applicable

3 MHz

15

4

2

5 MHz

25

4

2

10 MHz

50

6

3

15 MHz

75

8

4

20 MHz

100

8

4

For periodic CQI report, Samsung eNB supports wideband reporting mode only.

Aperiodic CQI: The aperiodic CQI reporting on PUSCH can be triggered by a CSI request within DCI format 0 on PDCCH or within random access response grant belonging to a random access response message on PDSCH. The type of CQI report is configured in eNB by the RRC signalling. Samsung eNB supports wideband CQI and higher layer configured sub-band CQI reporting modes.


Key Parameters RTRV-CQI-REP/CHG-CQI-REP


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Description

CQI_REPORT_APERIODIC _SETUP

This parameter is set to enable or disable the use of aperiodic report mode. Release: aperiodic report mode is disable. Setup: aperiodic report mode is enable. When aperiodic CQI mode is setup, subband CQIs for all subbands can be reported simultaneously. Thus, with aperiodic CQI, frequency selective scheduling can be enhanced, while uplink overhead is increased to report it.

WIDE_SUBBAND_SELECT

This paramter is available only when aperiodic CQI report is disabled. Selects a wideband/subband CQI option. WideBand: periodic wideband CQI only. SubBand: periodic wideband CQI + periodic subband CQI. Wideband CQI is the indicator to represent an average channel quality for entire bandwidth, while Subband CQI is for each subband. When frequency selective scheduling is needed, subband CQI is used. Changing the parameter value while eNB is operating requires special care because it may cause abnormal operation.


Type Name

Type Description

AMC

DL RI

Count of feedback per Rank Indicator

DL Wideband CQI

Count of feedback per Wideband Channel Quality Indicator

DL MCS

Count of transmission per MCS

REFERENCE [1] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [3] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification


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LTE-ME3203, Aperiodic CQI Reporting INTRODUCTION For the downlink data transmissions in an LTE network, the eNodeB typically selects the modulation scheme and code rate depending on a prediction of the downlink channel conditions. An important input to this selection process is the Channel Quality Indicator (CQI) feedback transmitted by the UE in the uplink. CQI feedback is an indication of the data rate, which can be supported by the channel, considering the Signal to Interference plus Noise Ratio (SINR) and the characteristics of the UE receiver. The eNB supports two types of CQI reporting:

Periodic CQI is semi-statically configured by the eNB to be periodically transmitted on PUCCH.

Aperiodic CQI can be triggered on the PUSCH by a CSI request within DCI format 0 on PDCCH. It can also be triggered within random access response grant belonging to a random access response message on the PDSCH.

BENEFIT DL frequency selective scheduling to use sub-band CQI of all subbands. DL radio resource scheduling to serve the best resource allocation.


FEATURE DESCRIPTION The aperiodic CQI is sent by PUSCH and be triggered by the CQI request field within UL grant. The eNB configures the following types of CQI reporting through the RRC signaling:

Wideband reporting UE-selected sub-band reporting Higher layer configured sub-band reporting In UE-selected sub-band reporting, the UE reports average CQI of M number of preferred sub-band in addition to wideband CQI. While it reports wideband CQI and sub-band CQI of all subbands in higher layer configured sub-band reporting. Because higher layer configured CQI reporting provides more information than UE-selected sub-band reporting, the Samsung eNB only operates higher layer configured CQI reporting. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The eNB uses aperiodic CQI for frequency selective scheduling because sub-band information of periodic sub-band CQI is limited, as follows:

The UE reports only the selected sub-band CQI in bandwidth part. The UE does not transmit sub-band CQIs for the entire bandwidth simultaneously, which leads to longer reporting time. The eNB also uses aperiodic CQI in DL Carrier Aggregation. When the Carrier Aggregation feature is enabled, the use of two bits for CSI request is applicable. According to CSI request field, aperiodic CQI reporting is triggered for Pcell or Scell.

SYSTEM OPERATION How to Activate Execute CHG-CQI-REP to set CQI_REPORT_APERIODIC_SETUP to ci_Config_Setup for enabling aperiodic CQI report when DL Frequency Selective Scheduling (FSS) is enabled.

Execute CHG-CQI-REP to set CQI_REPORT_APERIODIC_SETUP_R10 to ci_Config_PcellScellSetup for enabling aperiodic CQI report when Carrier Aggregation feature is enabled.

Key Parameters RTRV-CQI-REP/CHG-CQI-REP Parameter

Description

CQI_REPORT_APERIODIC _SETUP

This parameter is set to enable or disable the use of aperiodic report mode. Release: Aperiodic report mode is disabled. Setup: Aperiodic report mode is enabled.

CQI_REPORT_APERIODIC _SETUP_R10

Config aperiodic report mode for Rel 10. 0: ci_Config_ReleaseAll 1: ci_Config_PcellSetup 2: ci_Config_ScellSetup 3: ci_Config_PcellScellSetup


REFERENCE [1] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME3206, Periodic Channel Status Reporting INTRODUCTION The principle of link adaptation is fundamental to the design of a radio interface which is efficient for packet-switched data traffic. Unlike the early versions of Universal Mobile Telecommunication System (UMTS), which used fast closedloop power control to support circuit-switched services with a roughly constant data rate, link adaptation in High Speed Packet Access (HSPA) and LTE adjusts the transmitted information data rate, that is, modulation scheme and channel coding rate, dynamically to match the prevailing radio channel capacity for each user. For the downlink data transmissions in LTE, eNB typically selects the modulation scheme and code rate depending on a prediction of the downlink channel conditions. An important input to this selection process is the Channel Quality Indicator (CQI) feedback transmitted by User Equipment (UE) in uplink. The CQI feedback is an indication of the data rate which can be supported by the channel, taking into account Signal to Interference plus Noise Ratio (SINR) and the characteristics of the UE‟s receiver. For the LTE uplink transmissions, the link adaptation process is similar to that for downlink, with the selection of modulation and coding schemes also being under the control of eNB. An identical channel coding structure is used for uplink, while the modulation scheme may be selected between QPSK and 16 QAM, and, for the highest category of UE, also 64 QAM. The main difference from downlink is that instead of basing the link adaptation on CQI feedback, eNB can directly make its own estimate of the supportable uplink data rate by channel sounding, for example using Sounding Reference Signals (SRS). A final important aspect of link adaptation is its use in conjunction with multi-user scheduling in time and frequency, which enables the radio transmission resources to be shared efficiently between users as the channel capacity to individual users varies. The CQI can therefore be used not only to adapt the modulation and coding rate to the channel conditions, but also for the optimization of the time/frequency selective scheduling and for inter-cell interference management.

BENEFIT Enable link adaptation from facilitating this feature Enable downlink radio resource scheduling to serve the best resource allocation


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DEPENDENCY AND LIMITATION Dependency This feature can be enabled in case of uplink 64 QAM.

FEATURE DESCRIPTION In cellular communication systems, the quality of the signal received by UE depends on the channel quality from the serving cell, the level of interference from other cells, and the noise level. To optimize system capacity and coverage for a given transmission power, the transmitter should try to match the information data rate for each user to the variations in received signal quality. This is commonly referred to as link adaptation and is typically based on Adaptive Modulation and Coding (AMC). The degrees of freedom for AMC consist of the modulation and coding schemes:

Modulation Scheme Low-order modulation (that is, few data bits per modulated symbol, for example, QPSK) is more robust and can tolerate higher levels of interference but provides a lower transmission bit rate. High-order modulation (that is, more bits per modulated symbol, for example, 64 QAM) offers a higher bit rate but is more prone to errors due to its higher sensitivity to interference, noise, and channel estimation errors. Therefore it is useful only when SINR is sufficiently high.

Code Rate In case of given modulation, the code rate can be chosen depending on the radio link conditions. A lower code rate can be used in poor channel conditions and a higher code rate in the case of high SINR. The adaptation of the code rate is achieved by applying puncturing or repetition to the output of a mother code. A key issue in the design of the AMC scheme for LTE was whether all Resource Blocks (RBs) allocated to one user in a subframe should use the same Modulation and Coding Scheme (MCS) or whether MCS should be frequency dependent within each subframe. It was shown that in general only a small throughput improvement arises from a frequency-dependent MCS compared to an RBcommon MCS in the absence of transmission power control, and therefore the additional control signalling overhead associated with frequency-dependent MCS is not justified. Therefore in LTE the modulation and channel coding rates are constant over the allocated frequency resources for a given user, and time-domain channel-dependent scheduling and AMC is supported instead. In addition, when multiple transport blocks are transmitted to one user in a given subframe using multistream Multiple-Input Multiple-Output (MIMO), each transport block can use an independent MCS. In LTE, UE can be configured to report CQIs to assist eNB in selecting an appropriate MCS to use for the downlink transmissions. The CQI reports are derived from the downlink received signal quality, typically based on measurements of the downlink reference signals. It is important to note that, like HSDPA, the reported CQI is not a direct indication of SINR in LTE. Instead, UE eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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reports the highest MCS that it can decode with a transport block error rate probability not exceeding 10 %. Thus, the information received by eNB takes into account the characteristics of the UE‟s receiver, and not just the prevailing radio channel quality. Hence, UE that is designed with advanced signal processing algorithms (for example, using interference cancellation techniques) can report a higher channel quality and, depending on the characteristics of eNB scheduler, can receive a higher data rate. The following table shows the list of modulation schemes and code rates which can be signalled by means of a CQI value:

The AMC can exploit the UE feedback by assuming that the channel fading is sufficiently slow. This requires the channel coherence time to be at least as long as the time between the UE‟s measurement of the downlink reference signals and the subframe containing the correspondingly-adapted downlink transmission on Physical Downlink Shared Channel (PDSCH). However, a trade-off exists between the amount of CQI information reported by UEs and the accuracy with which AMC can match the prevailing conditions. The frequent reporting of CQI in the time domain allows better matching to the channel and interference variations, while fine resolution in the frequency domain allows better exploitation of frequency-domain scheduling. However, both lead to increased feedback overhead in uplink. Therefore, eNB can configure both the time-domain update rate and the frequency-domain resolution of CQI.


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CQI Feedback In case of CQI feedback, eNB employs the periodic CQI reporting and UE will transmit the reports using PUCCH. Only wideband and UE-selected sub-band feedback is possible for the periodic CQI reporting, for all downlink (PDSCH) transmission modes. The type of periodic reporting is configured by RRC signalling of eNB. For the wideband periodic CQI reporting, the period can be configured to 2, 5, 10, 16, 20, 32, 40, 64, 80, and 160 ms or OFF, and UE reports one wideband CQI value for the whole system bandwidth. In the case of „UE selected sub-band‟, the total number of sub-bands N is divided into J fractions called bandwidth parts. A CQI value is computed and reported for a single selected sub-band from each bandwidth part, along with the corresponding sub-band index. A value of J depends on the system bandwidth as summarized in below table. The following table shows the periodic CQI reporting with UE-selected sub-bands: sub-band size (k) and bandwidth parts (J) versus downlink system bandwidth. System Bandwidth (RBs)

Sub-band Size (k RBs)

Number of Bandwidth parts (J)

6-7

(Wideband CQI only)

1

8-10

4

1

11-26

4

2

27-63

6

3

64-110

8

4

Multiple Antenna Transmission Case Channel Quality Indicator (CQI) A CQI index is defined by a channel coding rate value and modulation scheme (QPSK, 16 QAM, and 64 QAM) as given in first table of description. In addition to 4-bit absolute CQI indices, three differential CQI values are defined to reduce the CQI signaling overhead. Note that UE always reports the wideband CQI even when UE-selected sub-band feedback is used for the periodic reporting. This is because wideband CQI is required for setting the power levels for downlink control channels that are transmitted in a frequency diverse transmission format over the wideband to exploit frequency diversity. Precoding Matrix and Rank Indicator (PMI and RI) The MIMO transmission rank can be either one or two for the case of two-antenna ports requiring single-bit Rank Indicator (RI). The numbers of precoders for the two antenna ports are four and two for rank-1 and rank-2 respectively. Therefore, Precoding Matrix Indicator (PMI) requires two bits for rank-1 and a single bit for rank-2. In case of four antenna ports, the MIMO transmission rank can be one, two, three, or four requiring two bit rank indication. The number of precoders for each rank is 16 and therefore requires four bit PMI indication.

SYSTEM OPERATION How to Activate This feature is basically enabled and operator cannot disable. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Key Parameters RTRV-CQI-REP/CHG-CQI-REP Parameter

Description

TRANSMISSION_MODE

Transmission mode: ci_tm1: Single-antenna port (port 0), DCI format 1 or 1A is used. ci_tm2: Transmit diversity, DCI format 1 or 1A is used. ci_tm3: Open-loop spatial multiplexing, DCI format 2A or 1A is used. ci_tm4: Closed-loop spatial multiplexing, DCI format 2 or 1A is used. ci_tm5: MU-MIMO, DCI format 1D or 1A is used. ci_tm6: Closed-loop rank-1 precoding, DCI format 1B or 1A is used. ci_tm7: Single-antenna port (port 5), DCI format 1 or 1A is used. ci_tm8: Single-antenna port (port 7/port 8), DCI format 2B or 1A is used ci_tm9: UE specific RS based Transmission (Rel 10) ci_tm10: UE specific RS based Transmission (Rel 11)


REFERENCE [1] 3GPP TS 36.212 Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding [2] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME3301, Uplink Scheduler Enhancement INTRODUCTION Miscellaneous uplink scheduler enhancement items compose this feature.

BENEFIT The benefit depends on item. Details are described in 'feature description'.

DEPENDENCY None

LIMITATION None

SYSTEM IMPACT Performance and Capacity PUSCH 1RB allocation and Efficient VoLTE resource allocation for IPv6.

It reduce unnecessary UL resource allocation which leads to UL capacity improvement.

FEATURE DESCRIPTION PUSCH 1RB allocation PUSCH 1RB allocation is allowed. The benefit is UL capacity improvement as saving UL resource.

Efficient VoLTE resource allocation for IPv6 In case of RoHC is not enabled, the RTP packet size for IPv6 is larger compared to the RTP packet size for IPv4 since the IP header size is different. For the efficient UL VoLTE scheduling in MAC scheduler, IP version is indicated to the MAC scheduler and it allocaes UL resource corresponding to the size of RTP packet. The benefit is UL capacity improvement as saving UL resource.


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REFERENCE [1] 3GPP TS 36.211 E-UTRA Physical Channels and Modulations [2] 3GPP TS 36.213 E-UTRA Physical Layer Procedures [3] 3GPP TS 36.331 E-UTRA Radio Resource Control (RRC) Protocol Specification


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LTE-ME3304, Scheduling with QoS Support INTRODUCTION The LTE scheduler allocates the downlink and uplink resources dynamically among the bearers while maintaining their desired QoS level. To make a scheduling decision, the LTE scheduler uses the following information as input:

Radio conditions at UE identified through measurements made at eNB and/or reported by the UE.

The state of different bearers, such as uplink Buffer Status Reports (BSR) that are required to provide support for QoS-aware packet scheduling.

The QoS attributes of bearers and packet forwarding parameters associated with the QCIs. The Proportional Fair (PF) scheduler uses channel quality information and average throughput as the factors to determine the priority of scheduling users. When QCI based priority information is available, along with the PF parameters, the priority and delay budget information are used to determine the scheduling priority.

BENEFIT The operator can differentiate the traffic data according to the QoS class of LTE users.

LTE users can be served the better QoS with their priority in the system.


FEATURE DESCRIPTION Multi-user scheduling is one of the main features in LTE systems. It distributes the available resources among active users to meet their QoS requirements. The data channel, PDSCH, is shared among the users, which means the spectrum should be distributed every TTI among them. Packet schedulers, for both downlink and uplink, are deployed at eNB and operate with a granularity of one TTI and one RBG in the time and frequency domain, respectively. Resource allocation for each UE is usually based on the comparison of scheduling metrics. Information considered in calculating the metric is summarized as follows:

Status of Transmission Queues eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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For a UE with non-zero size of transmission queue is regarded as candidate for scheduling in a given TTI.

Channel Quality Reported CQI and RI values can be used to allocate resources to users experiencing better channel conditions (For example, the higher the expected throughput, higher the metric).

Resource Allocation History Information on the past achieved performance can be used to improve fairness (for example, the lower the past achieved throughput, higher the metric).

Buffer Status For each UE category the size of soft buffer for HARQ processing is different. The downlink scheduler considers the buffer status of each UE depending on the UE's category to avoid buffer overflow.

Quality of Service Requirements The QCI value associated to each flow might be used to drive specific policies with the aim of meeting QoS requirements. In every TTI, the scheduler performs the allocation decision and sends this information to UEs through PDCCH. DCI messages in PDCCH payload inform UEs about RBs allocated for data transmission on PDSCH in the downlink. Moreover, DCI messages are used to inform users about the dedicated radio resources for their data transmission on the PUSCH in the uplink. The LTE schedulers support the channel sensitivity. The basic idea is to allocate resource for UEs experiencing good channel conditions based on the selected metric.

Key Design Aspect Differences among resource allocation strategies are mainly based on the trade-off between decision optimality and computational complexity. The following are the list of the main design factors that always should be considered before defining the allocation policy for LTE:

Complexity and Scalability The LTE packet scheduler works with a time granularity of 1 ms: It takes allocation decisions at every TTI. Low complexity and scalability are therefore fundamental requirements for limited processing time and memory usage. Finding the best allocation decision through complicated and non-linear optimization problems or through an exhaustive search over all the possible combinations is too expensive in terms of computational cost and time.

Spectral Efficiency The effective utilization of radio resources is one of the main goals to be achieved. For this, several types of performance indicators can be considered. For instance, a specific policy can aim at maximizing the number of users served in a given time interval or, more commonly, the spectral efficiency by always serving users that are experiencing the best channel conditions. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Fairness A blind maximization of the overall cell throughput enables effective channel utilization in terms of spectral efficiency. However, this brings to very unfair resource sharing among users. Fairness is therefore a major requirement that should be considered to guarantee the minimum performance to the cell-edge users.

QoS Provisioning The QoS constraints can vary depending on the application and they are usually mapped into some parameters, such as minimum guaranteed bit-rate, maximum delay, packet loss rate, and so on. The QoS aware scheduler differentiates the metric for each QoS class and gives a higher priority to higher requirements.

Scheduling Strategies This section is classified into the following topics:

Channel-unaware Channel-aware/QoS-unaware Channel-aware/QoS-aware Channel unaware-strategy Firstly introduced in wired networks, channel unaware strategies are based on the assumption of time-invariant and error-free transmission media. While their direct application in LTE is not realistic, they are typically used jointly with channelaware approaches to improve system performance. The round robin method performs fair sharing of time resources among users. In this context, the concept of fairness is related to the amount of time in which the resource is occupied by a user. However, this approach is not fair in terms of user throughput especially in wireless systems which depends not only on the amount of occupied resources, but also on the quality of channel conditions. Channel-aware/QoS-unaware Strategies The CQI feedbacks are periodically or aperiodically reported by the UE. The scheduler estimates the channel quality perceived by each UE, and hence it can predict the maximum achievable throughput.

Maximum C/I Scheduling This aims at maximizing the overall throughput by assigning RBs to the user that can achieve the maximum throughput in a given TTI. On the other hand, it performs unfair resource sharing as users with poor channel conditions are only get a low percentage of the available resources.

Proportional Fair Scheduler


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A typical way to find a trade-off between requirements on fairness and spectral efficiency is the use of this scheme. The idea is that the past average throughput can act as a weighting factor of the expected data rate, so users in bad conditions are served within a certain time. Scheduling priority used on RB allocation is Proportional Fair (PF) priority, and PF priority is calculated as follows: PF Priority = (R)^(β)/(Average_Tput)^(α) The R is an available data rate determined by the channel quality. This is calculated based on the CQI/RI feedback from each UE and the occurrence of ACK or NACK event for the previous allocations. Average_Tput is the UE average throughput. Parameters α and β are fairness weight and channel quality weight, respectively. By configuring α and β dominant factor for the PF priority can be changed. For example if α is greater than β, then fairness between users are enhanced. On the contrary, if β is greater than α, the system throughput can be enhanced. Channel-aware/QoS-aware Strategies 9 QCI profiles are supported. The eNB also supports configuring operator specific QCI (128 to 254). Each QCI profile maps to a set of parameters such as priority, packet delay budget, packet error loss rate, and service type. The QCI information is received by eNB from EPC. Each UE can support more than one bearer and each bearer can be configured with a specific QCI. The priority is used in the QoS based scheduling to prioritize the users. The packet delay budget specifies the soft upper bound for the time that a packet can be delayed between the UE and PGW. The PELR defines an upper bound for the rate of SDUs, for example, IP packets, that have been processed by the sender of a link layer protocol. This parameter is used to determine appropriate link layer protocol configurations, for example, RLC and HARQ retransmissions in E-UTRAN. The service type defines whether the service is a Guaranteed Bit Rate (GBR) or a nonGBR service. The QoS information also includes information such as GBR, maximum Bit Rate (MBR), and UE-Aggregate Maximum Bit Rate (AMBR). The GBR and MBR information are provided on per bearer basis. These parameters are provided from EPC to eNB. The GBR provides the rate that needs to be guaranteed for a GBR bearer by the scheduler. The MBR indicates the maximum allowed rate for the GBR bearer. The UE-AMBR or AMBR specifies the maximum allowed rate for all the non-GBR bearers of the UE. The eNB enforces the GBR, MBR, and UEAMBR rules as required during scheduling operation. With QoS based scheduling, the eNB prioritizes the GBR bearer scheduling over non-GBR bearer except QCI 5, which is typically configured for IMS signalling. The QCI 5 always has the highest priority. Among GBR bearers, the QCI priority and the Packet Delay Budget (PDB) of bearer are used to determine the ranking along with the PF scheduler parameters. Among non-GBR bearers, only the PF scheduler parameters are used to prioritize the bearers.


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SYSTEM OPERATION How to Activate Execute the CHG-DL-SCHED command to change the parameter alpha, beta, and/or gamma. Scheduler

ALPHA

BETA

GAMMA

Max C/I

0

non-zero

0

Proportional Fairness (PF)

non-zero

non-zero

0

QoS-aware

non-zero

non-zero

non-zero

Key Parameters Parameter

Description

ALPHA

Fairness weight in PF scheduler. The larger alpha is, the better the fairness is.

BETA

Channel quality weight in PF scheduler. The larger beta is, the better the channel efficiency is.

GAMMA

Delay weight in scheduling metric. The larger gamma is, the smaller scheduling delay is. However, if it is set too high, system capacity can be decreased because scheduler considers delay excessively.

Counters and KPIs There is no related counter or KPI.

REFERENCE [1] 3GPP TS 36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification


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LTE-ME3305, Semi-persistent Scheduling INTRODUCTION Semi-persistent scheduling (SPS) allocates periodic resources semi-statically for applications such as VoIP, instead of dynamic allocation of resources. SPS is similar to a virtual circuit-based service. It is pre-configured to allow eNB and UE to interoperate without the physical control channel.

BENEFIT Enabling this feature is useful for services such as VoIP for which the data packets are small, periodic and semi-statically in size.

This reduces the control signaling overhead and improves capacity.

DEPENDENCY UE device should supports SPS.

LIMITATION For TDD, E-UTRAN does not support both TTI bundling and semi-persistent scheduling at the same time in this release of specification. (3GPP TS. 36.331)

This feature is not supported in Indoor Pico eNB.

SYSTEM IMPACT Performance and Capacity This feature can reduce the control signaling load especially for the VoLTE UE.

FEATURE DESCRIPTION SPS operation Dynamic scheduling requires sending the specific downlink or uplink resource assignment message over signaling channel. It is unavoidable for Internet data scheduling which is un-predictable and bursty. However, the packet transmission of VoLTE traffic is more predictable in the sense of packet transmission period and packet size.


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By using the predictable nature of VoLTE traffic, Semi-Persistent Scheduling (SPS) method assigns persistently allocated transmission resources for the initial transmissions of VoIP packets instead of dynamic scheduling. Due to the small size of VoLTE packet, singling overhead for dynamic scheduling can be relatively large for VoLTE call. SPS can enhance the VoLTE capacity by reducing the signaling overhead in Physical Downlink Control Channel (PDCCH). Figure below depicts the operation of SPS.

The initial transmissions of VoIP packets are sent without associated scheduling control information. The semi-persistent scheduling (SPS) related configuration is configured by the higher layer (Radio resource control, RRC). For example, the packet transmission interval for initial transmission and SPS-specific UE identifier, that is, SPS C-RNTI, are configured through RRC message. The SPS activation and deactivation is scheduled by the Physical Downlink Control Channel (PDCCH) with SPS-C-RNTI. During the period of a talk spurt:

The SPS is activated by sending the specific PDCCH (SPS C-RNTI) with allocating transmission resources.

The semi-persistent allocation is released during the silence periods. During a period of silence:

The silent indication descriptor (SID) packets are scheduled dynamically every period.

In downlink, retransmissions are also scheduled dynamically


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The actual SPS transmission is started at reception of SPS resource allocation (with NDI=0) via SPS-C-RNTI over PDCCH. The timing and the allocated resource in frequency domain become reference for the following semipersistently allocated packet transmissions. Based on the SPS interval received via RRC and the first SPS resource allocation, the next packet can be transmitted in the same resource block after the configured time interval elapses. As described in the below figure, no additional signaling over PDCCH is required after the first SPS resource allocation.

On the other hand, the HARQ retransmissions may occur unpredictable. In this case, the resource for HARQ retransmissions of initial packets are assigned by explicit signaling over PDCCH. The HARQ retransmissions in SPS is also signaled by using SPS-C-RNTI, but NDI value is set to 1 to be distinguished from initial packet allocation for SPS. If the eNB finds that the talk spurt is finished, pre-allocated SPS resource allocation is released by PDCCH signaling. Then, the incoming packets during silent spurt, for example, Silence Interval Duration (SID) Packets that are generated by the VoIP codec, are allocated via dynamic scheduling. There exists a risk that UE continuously sends the UL packets if the UE could not receive PDCCH signaling indicating SPS release. In order to reduce the risk, UE implicitly assumes that SPS release is triggered when a certain number of MAC PDUs not containing any MAC SDUs have been sent. If the eNB finds that the talk spurt is started again, the eNB signals SPS resource allocation again, and pre-allocate the resources periodically. In Samsung‟s VoLTE operation scenario, the SPS is applied only for uplink, not for downlink. In downlink VoLTE scheduling, the limiting factor(bottleneck) of the VoLTE user capacity is PDSCH resource rather than PDCCH resource. So the technical benefit of DL SPS is marginal. UL SPS can be activated when the following conditions are satisfied. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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For QCI 1, the scheduling type that is, dynamic scheduling or SPS, should be set as SPS by configuring SCHEDULING_TYPE parameter through CHG-QCIVAL command.

The number of the VoLTE users with active QCI 1 bearer exceeds a certain threshold. The threshold for activating DL and UL SPS can be controlled by using CHG-MAC-VOIP command. Since DL SPS is not included in the Samsung‟s VoLTE operation scenario, the threshold for DL is set as the maximum number of RRC connected UEs (600 UEs)

The sub-frame bundling is setup for the UE. The size of required TBS for a VoLTE packet becomes above the certain thresholds. UL SPS resource is released (deactivated in eNB) when it is detected by eNB that UE release SPS (implicit release).

EVS (Enhanced Voice Service) codec support EVS codec is introduced in 3GPP Release 12 to increase voice service quality. It supports high-quality, high-efficiency audio coding for narrowband, wideband, super-wideband, and optionally full-band signal. 8, 16, 32, and 48 kHz sampling frequencies are supported while AMR-NB and AMR-WB supports 8kHz and 16 kHz, respectively. EVS codec supports wide range of bit-rate from 7.2 kbps up to 128 kbps, 5.9 kbps variable bit-rate as shown in the following table. Also, nine AMR-WB Interoperable modes are supported: 6.60, 8.85, 12.65, 14.25, 15.85, 18.25, 19.85, 23.05, and 23.85 kbps. Source codec bit-rate (kbit/s)

Signal bandwidths supported

Source Controlled Operation Available

5.9 (SC-VBR)

NB, WB

Yes (Always On)

7.2

NB, WB

Yes

8.0

NB, WB

Yes

9.6

NB, WB, SWB

Yes

13.2

NB, WB, SWB

Yes

13.2 (channel aware)

WB, SWB

Yes

16.4

NB, WB, SWB, FB

Yes

24.4

NB, WB, SWB, FB

Yes

32

WB, SWB, FB

Yes

48

WB, SWB, FB

Yes

64

WB, SWB, FB

Yes

96

WB, SWB, FB

Yes

128

WB, SWB, FB

Yes

The size of required TBS for a VoLTE packet using EVS codec can be input as a system parameter.


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How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to active this feature. Activation Procedure To activate this feature, do the following:

Run CHG-DPHY-SPS and set spsEnable to enable the UL semi-persistent scheduling.

Also, run CHG-QCI-VAL and set SchedulingType to enable the UL semipersistent scheduling.

DL SPS cannot be activated. Deactivation Procedure To deactivate this feature, do the following:

Run CHG-DPHY-SPS and set spsEnable to disable the UL semi-persistent scheduling.

Also, run CHG-QCI-VAL and set SchedulingType to disable the UL semipersistent scheduling.

DL SPS cannot be activated. Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter description of CHG-DPHY-SPS/RTRV-DPHY-SPS Parameter

Description

spsEnable

This parameter is used to enable to use SPS. '0': This feature is not used. '1': This feature is used

Parameter description of CHG-QCI-VAL/RTRV-QCI-VAL Parameter

Description

SchedulingType

This parameter is the scheduling type of the QoS class identifier (QCI). Entered


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Description parameter value is used for scheduling in the MAC layer. Dynamic_scheduling: The QCI uses the dynamic scheduling. SPS_scheduling: The QCI uses the SPS scheduling.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter description of CHG-DPHY-SPS/RTRV-DPHY-SPS Parameter

Description

p0NominalPUSCHPersistent

This parameter specifies the SPS P0 value used in power control. The unit of value is dBm.

p0UEPUSCHPersistent

This parameter specifies the SPS P0 value used in power control, which is determined per UE. The unit of value is dB.

SemiPersistSchedTbsDL

This parameter provides information about the combinations of the allocated number of RB, MCS and TBS size for DL SPS.

SemiPersistSchedTbsUL

This parameter provides information about the combinations of the allocated number of RB, MCS and TBS size for UL SPS.

Parameter description of CHG-MAC-VOIP/RTRV-MAC-VOIP Parameter

Description

SPSApplyNumofUEThreshDL

This parameter is the threshold number of UEs for DL SPS application

SPSApplyNumofUEThreshUL

This parameter is the threshold number of UEs for UL SPS application


Type Name

Type Description

Semi-Persistent Scheduling

ULSpsConfigAtt

Counted when eNB has sent the RRCConnectionReconfiguration message including UL SPS Configuration Setup to UE.

ULSpsConfigSucc

Counted when eNB has received the RRCConnectionReconfigurationComplete message for the UL SPS Configuration Setup request from UE.

ULSpsConfigNoAvg

The number of UL SPS configured UEs is counted every 2 seconds.

There are no specific Key Performance Indicators (KPIs) associated with this feature.


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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [3] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification


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LTE-ME3307, UL Sub-frame Bundling INTRODUCTION When a User Equipment (UE) is at the cell edge, it may undergo power shortage due to the transmission power limitation. To overcome the power shortage at cell edge, 3GPP LTE provides TTI bundling operation. When TTI bundling is configured by RRC, HARQ transmissions for a transport block are performed in consecutive TTIs without waiting for HARQ feedback. Each HARQ transmission depends on incremental redundancy. The eNB accumulates the received energy of all transmissions and sends HARQ feedback only one time after the last redundancy version of the transport block is received. Therefore, TTI bundling operation reduces the number of required HARQ feedback messages and the overhead resulting from uplink grant.

BENEFIT Extending uplink cell coverage and helpful for applications such as VoIP.

DEPENDENCY TTI bundling supportable UE.

LIMITATION For TDD, TTI bundling is only applicable to U/D config 0, 1 and 6. Others are not available because there's not enough UL subframes in 10ms radio frame (it should be equal to or greater than 4). This feature is not supported in Indoor Pico eNB.



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FEATURE DESCRIPTION TTI bundling (or subframe bundling) is intended to improve the uplink coverage performance of Voice over IP (VoIP), that is, improve air-interface performance in scenarios where coverage is limited by the UE transmit power capability. The general concept of TTI bundling is illustrated in below figure. Each VoIP transport block is passed to the physical layer where it has CRC bits added before being channel coded using turbo coding. 4 duplicates of the channel coded transport block are generated prior to rate matching. Each duplicate is processed using a different Redundancy Version (RV). This provides the eNB receiver with an Incremental Redundancy soft combining gain. The set of codewords are modulated and mapped onto 4 consecutive uplink subframe. Figure below depicts concept of TTI bundling.

TTI bundling groups 4 consecutive uplink TTI to generate an effective TTI duration of 4 ms. These consecutive TTI define the bundle size. 3GPP TS36.321 specifies a fixed bundle size of 4. Transmissions belonging to each bundle size are sent without waiting for any HARQ acknowledgements. This corresponds to using autonomous retransmission. Each bundle of 4 TTI requires a single resource allocation from the eNB and a single HARQ acknowledgements.


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3GPP TS 36.321 specifies that a maximum of 3 resource block can be allocated when TTI bundling is used. In addition, the modulation scheme is limited to QPSK. The combination of upto 3 resource blocks and QPSK provides sufficient capacity to transfer the bit rate required by VoIP. The same modulation and coding scheme (MCS) and frequency bandwidth are used for all 4 TTI belonging to the bundle. The eNB can instruct the UE whether or not to use TTI bundling within the RRC Connection Setup, RRC Connection Reconfiguration or RRC Connection Reestablishment messages. TTI bundling is applicable to both FDD and TDD. In the case of FDD, the number of HARQ process is halved from 8 to 4. The eNB generates a single HARQ acknowledgement for each bundle of 4 TTI. The timing of HARQ acknowledgement is based on the timing of the last TTI within the bundle, that is, the acknowledgement is sent 4 subframes after the last TTI in the bundle. The complete bundle of 4 TTI is retransmitted when a HARQ acknowledgement indicates that a retransmission is required. The retransmission delay is 16 subframe (16 ms) when using TTI bundling, comparing to the retransmission delay of 8 subframes (8 ms) when TTI bundling is not used. Below figure illustrates the set of 4 HARQ processes for TTI bundling with FDD. Each transmission belonging to a specific HARQ process is separated by 16 subframes. Figure below depicts FDD HARQ processes for TTI bundling.


How to Activate This section provides the information that you need to configure the feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Preconditions There are no specific preconditions to active this feature. Activation Procedure Run CHG-TRCH-INF and set ttiBundling to enable the UL subframe bundling. Deactivation Procedure Run CHG-TRCH-INF and set ttiBundling to disable the UL subframe bundling.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter description of CHG-TRCH-INF/RTRV-TRCH-INF Parameter

Description

ttiBundling

This parameter is used to enable to use TTI bundling. '0': This feature is not used. '1': This feature is used

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter description of CHG-TRCH-INF/RTRV-TRCH-INF Parameter

Description

ttibInTBS

Supportable TBS threshold for sub-frame bundling mode setup

ttibOutTBS

Supportable TBS threshold for sub-frame bundling mode release

Counters and KPIs Table below outlines the main counters and main Key Performance Indicators (KPIs) associated with this feature. Family Display Name

Type Name

Type Description

TTI Bundling

TtibActAtt

Attempt Count of TTIB Activation

TtibActSucc

Success Count of TTIB Activation

TtibDeactAtt

Attempt Count of TTIB Deactivation

TtibDeactSucc

Success Count of TTIB Deactivation

TtibNoAvg

Average number of the TTIB Activated UEs

TtibNoMax

Maximum number of the TTIB Activated UEs

Family Display Name

Type Name

Type Description

TTI Bundling Time

TtibActTimeAvg

Average time of the TTIB activated duration per UE


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Chapter 6 Radio Scheduler Family Display Name

Type Name

Type Description

TtibActTimeRate

Percentage of TTIB Activated duration in RRC Holding Time per UE

REFERENCE [1] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [2] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification


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LTE-ME3309, Resource allocation enhancement for SIB INTRODUCTION The System Information (SI) is broadcasted using a Master Information Block (MIB) and a series of System Information Blocks (SIBs). The Resource Elements (REs) used by MIB on PBCH are fixed as the central 72 subcarriers by 3GPP specification, but REs for SIB can be controlled by MAC scheduler. This feature provides the method for control the resource used for SIB. New resource allocation methods for SIB not only ensure reliable reception of SIBs but also reduce overhead caused by SIBs.

BENEFIT Resource overhead caused by SIBs can be adjusted in consideration of reliable reception of System Information.


FEATURE DESCRIPTION The System Information (SI) consists of Master Information Block (MIB) and System Information Block (SIB). The MIB is the only SI transferred using BCH and PBCH. SIBs are transferred using DL-SCH and PDSCH. SIB1 has its own RRC message whereas other SIBs except SIB1 are encapsulated within the more general SI RRC message. The UE starts by reading MIB and this provides sufficient information to read SIB1. SIB1 provides scheduling information for the remaining SIB. The following table shows the summary of the information included within MIB and each of SIB: System Information

Content

Master Information Block

Downlink channel bandwidth, PHICH configuration, SFN

System Information Block 1

PLMN Id, tracking area code, cell selection parameters, frequency band, cell barring, scheduling information for other SIB


Access class barring, RACH, BCCH, PCCH, PRACH, PDSCH, PUSCH, PUCCH parameters, UE timers and constants, uplink carrier frequency


Cell reselection parameters


Intra-frequency neighbouring cell information for cell reselection


Inter-frequency neighbouring cell information for cell reselection


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Content


UMTS neighbouring cell information for cell reselection


GERAN neighbouring cell information for cell reselection


CDMA2000 neighbouring cell information for cell reselection


Home eNB name


Earthquake and Tsunami Warning System primary notification


Earthquake and Tsunami Warning System secondary notification


Commercial Mobile Alert Service (CMAS) notification


MBMS Single Frequency Network (MBSFN) configuration information

The set of Resource Elements (REs) used by MIB on PBCH is standardized by 3GPP, so does not require any additional signaling, that is, PBCH occupies the central 72 subcarriers within the first four OFDMA symbols of the second slot of a radio frame. The same allocation is made for both FDD and TDD. On the other hand, the set of REs used by SIB on PDSCH is not standardized by 3GPP, so requires additional signaling to inform UE of where to look. The PDCCH is used to provide this additional signaling. The PDCCH includes a CRC which is scrambled by System Information RNTI (SI-RNTI) if it includes resource allocation information relevant to SIB. The SI-RNTI has been standardized to have a single fixed value of FFFF. The eNB is responsible for scheduling the Resource Blocks (RBs) used to transfer SIB. The MIB and SIB1 are broadcast at a rate which is specified by 3GPP. The rate at which other SIBs are broadcast is implementation dependent. Downlink Control Information (DCI) format 1A and 1C can be used to signal PDSCH resource allocation for SIB. DCI format 1A supports localized/distributed resource allocation and DCI format 1C supports distributed resource allocation. Samsung eNB allocates SIB in localized manner, so DCI format 1A is used. When DCI format 1A is used to schedule resources for SIB, the modulation scheme is always QPSK (the modulation scheme specified within the MCS table is ignored). In addition, a Transport Block Size (TBS) index is set equal to the value of MCS bits rather than reading its value from the MCS table. The TPC command is not used for power control but is used to identify TBS. The most significant bit is ignored while the least significant bit indicates whether column two or three should be selected from within the TBS table, that is, the number of allocated RBs should be assumed to be either two or three for the purposes of identifying TBS. A value of zero corresponds to two assumed RBs, while a value of one corresponds to three assumed RBs. In summary, MCS index in DCI format 1A represents TBS of SIB, and link adaptation is done by a number of allocated RBs only. Samsung eNB supports to control a number of allocated RBs for SIBs. To adjust the number of RBs for SIBs, two different cases are categorized according to the urgency of SIB reception:

Normal Case Normally UE reads SI in RRC Idle mode to acquire the parameters necessary to access the network. While UE reads SIBs to access the network, UE does not need to acquire SIBs in urgent since SIBs are repeated periodically. The SIB1 is repeated at a rate of 20 ms by 3GPP specification, and other SIBs are repeated eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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according to the periodicity indicated by SIB1 in the range of {80, 160, 320, 640, 1280, 2560, and 5120 ms}. In normal case, the less number of RBs can be used to allocate SIBs to reduce resource overhead and increase capacity.

Exceptional case In certain cases, UE needs to acquire SIBs immediately, that is, modification of SI, ETWS, and CMAS. A UE in RRC connected should receive SIBs as fast as possible in case of SI modification since UE needs to communicate with eNB using the new SI. If UE communicates with eNB using the old SI, the communication would be fail, and moreover transmission of UE causes interference to other UEs. For ETWS and CMAS, UE needs to receive quickly to response against disasters. Samsung eNBs control a number of RBs for SIBs using two weight factors, BCCH_SCALING_FACTOR and BCCH_REDUCE_FACTOR as follows:

Exceptional case: Number of SIB RBs = Default RBs x BCCH_SCALING_FACTOR/16

Normal case: Number of SIB RBs = Number of SIB RBs for Exceptional case/ BCCH_REDUCE_FACTOR In above cases, Default RBs is the fixed number of RBs for SIB determined by its TBS. If BCCH_REDUCE_FACTOR = 1, Number of SIB RBs for Normal case becomes same as that for Exceptional case.

SYSTEM OPERATION How to Activate This feature is basically enabled and operator cannot disable. The operator can control a number of RBs for SIB by related parameters. Key Parameter RTRV-MACCTRLCH-FUNC/CHG-MACCTRLCH-FUNC Parameter

Description

BCCH_SCALING_FACTOR

This parameter determines the number of RBs for BCCH in exceptional case, which is given by: The number of default RB x BCCH_SCALING_FACTOR/16.

BCCH_REDUCE_FACTOR

This parameter determines the number of BCCH RBs in normal case in conjunction with BCCH_SCALING_FACTOR, which is given by: The number of default RB x BCCH_SCALING_FACTOR/BCCH_REDUCE_FACTOR/16.

Counters and KPIs There is no related counter or KPI. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LTE-ME3310, VoLTE concurrent rank adaptation INTRODUCTION If, for a particular UE, QCI1 bearer is open or QCI1-including multiple bearers are simultaneously open, Samsung scheduler had performed rank1 fixed allocation for all UE bearers from QCI1 open to QCI1 close, regardless of the UE report rank. It can cause the degradation of downlink throughput. For increase of the downlink throughput and robust transmission of QCI1 bearer in VoLTE concurrent environment, rank1 fixed allocation is applied to TTI including QCI1 bearer but, UE reported rank allocation is performed for TTI not including QCI1 bearer.

BENEFIT Downlink throughput of an LTE UE can be increased in VoLTE concurrent environment

DEPENDENCY Related Radio Technology: E-UTRAN (LTE)

LIMITATION None


FEATURE DESCRIPTION Samsung scheduler operation, when QCI1 bearer is open oIf, for a particular UE, QCI1 bearer is open or QCI1-including multiple bearers are simultaneously open, Samsung scheduler performs rank1 fixed allocation in TTI including QCI1, regardless of the UE report rank. oThe rank reported from UE is applied to data bearers in TTI not including QCI1 bearer.

Reason of rank1 fixed allocation for QCI1 bearer when QCI1 bearer open oVoLTE quality degradation and requirements The VoLTE quality degradation is very sensitive to packet delay and packet loss


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Thus, for VoLTE quality maintenance, a robust connection of VoLTE packets must be maintained Especially, an inaccurate UE rank feedback and a change of the frequent transmission rank may cause a great volume of packet loss, resulting in VoLTE quality degradation.

Inaccurate UE feedback information : Rank2

Real channel : Rank1

VoLTE Packet loss !!!

Samsung VoLTE operation stability oFor robust transmission of VoLTE, rank1 fixed allocation is performed in TTI including QCI1 bearer.


How to Active This feature is basically enabled.




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REFERENCE [1] 3GPP TS 36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification


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LTE-ME3401, Paging DRX INTRODUCTION In LTE, DRX mode can be enabled in both RRC_IDLE and RRC_CONNECTED states.

In the RRC_IDLE state, the UE is registered with Evolved packet system Mobility Management (EMM), however, does not have an active session. In this state, the UE can be paged for downlink traffic, and this DRX mode can be called as paging DRX. It can also initiate the uplink traffic by requesting RRC connection with the serving eNB.

In the RRC_CONNECTED state, the DRX mode is enabled during the idle periods during the packet arrival process, and this DRX mode can be called as active DRX. When there are no outstanding/new packets to be transmitted/ received, the eNB/UE can initiate the DRX mode.

BENEFIT This feature increases the battery life time.


FEATURE DESCRIPTION When the UE does not have packets to be received and/or transmitted for an extended period of time, the eNB can initiate the release of UE RRC connection and request MME to release the UE S1 connection. The eNB removes the UE context from the database. The MME and SGW only remove the eNB specific part of the UE context. During the idle mode, the UE wakes up periodically to listen to the downlink transmissions, following the DRX cycle. During the idle mode, the mobility is fully controlled by the UE, as the network is not aware of UE existence continuously. The UE performs the signal quality measurements with respect to the serving and neighboring eNBs according to measurement thresholds recommended by the serving eNB. Based on the signal quality measure, the UE selects a new serving eNB when the UE moves away from the current serving eNB. When the system information advertised by the new serving eNB does not include its tracking area, the UE performs a tracking area update to indicate its presence so that the network knows where to page UE in case of downlink data transfer. The UE can be paged by the network when there is data addressed to the UE. The UE returns to RRC_CONNECTED mode as soon as packet arrival is detected. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Two parameters, default DRX cycle and nB, are transmitted in SIB2, which allow UEs to calculate the DRX period and determine when to wake up to monitor for the paging message.

The following figure shows the paging procedure in network triggered service request case:

1 When S-GW receives a downlink data packet for UE, it buffers the downlink data packet and identifies which MME is serving that the UE.

2 The MME responds to S-GW with a downlink data notification ACK message. 3 The MME sends a paging message to eNBs belonging to the tracking area in which UE is registered.

4 The eNB calculates the paging occasion for the paged UE, and the paging is transmitted at the time of the UE‟s paging occasion.

5 When UE receives a paging indication, it initiates the UE triggered Service Request procedure.


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The UE in RRC idle mode uses DRX to reduce power consumption. The DRX cycle determines how frequently UE check for paging messages. The default DRX cycle is broadcasted within System Information Block 2 (SIB2). It can have 32, 64, 128, or 256 radio frames. These values correspond to the time intervals of 320, 640, 1280, and 2560ms. The UE can also propose its own DRX cycle length in the Attach Request and Tracking Area Update Request messages. The set of allowed values are the same as those used in SIB2. When UE proposes the DRX cycle, the smaller of two DRX cycles is used: the minimum of the default DRX cycle and the UE-specific DRX cycle.

SYSTEM OPERATION How to Activate Execute the CHG-PCCH-CONF command to set the configuration of the paging control channel. DEFAULT_PAGING_CYCLE corresponds to DRX cycle length in radio frames specified in 3GPP LTE standard. It can have 32, 64, 128, or 256 radio frames. When the value of DRX cycle increases, the paging occasion for each UE decreases.

Key Parameters RTRV-PCCH-CONF/CHG-PCCH-CONF Parameter

Description

DEFAULT_PAGING_CYC LE

This parameter is required to calculate the paging frame and paging occasion. When DRX is used, UE monitors a single paging occasion per DRX cycle. If UEspecific DRX is not set by the upper layer, the defaultPagingCycle is applied as the default DRX cycle.

N_B

This parameter required to calculate the paging frame and paging occasion using the TS.36.304 method, which is a multiple of the parameter DEFAULT_PAGING_CYCLE. Related specifications: 3GPP TS 36.304


Type Name

Type Description

Paging

DiscardedNbr

Paging record count discarded in the eNB

AttPaging

Paging transmission attempt count

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LTE-ME3402, Active DRX INTRODUCTION In LTE, one of the technique to improve the battery power consumption of UE is Discontinuous Reception (DRX). Packet data traffic is very bursty such that it transmits traffic for a short period and there is not transmission for a long time. Naturally, in a delay point of view, scheduler will be better to observe downlink control signal at every subframe and react instantly according to the traffic condition in order to receive uplink scheduling grant or downlink data transmission. However, the power consumption of UE is also important point not to be neglected. In this point of view, DRX technique make an active (or RRC_connected) state UE to improve power consumption. Active UE only observes control signal in a subframe indicated by active time, and in other subframes switches off its receiver circuit to reduce power consumption.

BENEFIT Enabling this feature results in longer battery life times.


LIMITATION None

SYSTEM IMPACT Performance and Capacity This feature can enhance the battery consumption of UE by making discontinuous reception in the UE side.

FEATURE DESCRIPTION LTE provides methods for the UE to micro-sleep even in the active state to reduce power consumption while providing high QoS and connectivity. DRX in the LTE sense means that the UE is not monitoring the PDCCH in the given subframe and is allowed to go to power saving mode. DRX parameter only impacts the downlink performance for a UE. The DRX concept contains different user-specific parameters that are configured via higher layer signaling. These parameters are described in following table. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 6 Radio Scheduler DRX Parameter

Description

DRX Cycle

Specifies the periodic repetition of the On Duration followed by a possible period of inactivity

On Duration timer

This parameter specifies the number of consecutive subframes at the beginning of a DRX cycle.

DRX Inactivity Timer

Specifies the number of consecutive PDCCH-subframe(s) after successfully decoding a PDCCH indicating an initial uplink or downlink user data transmission for this UE

DRX Retransmission Timer

Specifies the maximum number of consecutive PDCCH-subframe(s) for as soon as a DL retransmission is expected by the UE.

DRX Short Cycle

Specifies the periodic repetition of the On Duration followed by a possible period of inactivity for the short DRX cycle

DRX Short Cycle Timer

This parameter specifies the number of consecutive subframe(s) the UE follows the short DRX cycle after the DRX Inactivity Timer has expired.

DRX Start Offset

Specifies the subframe where the onDurationTimer starts in DRX cycle.

Basically, upon knowledge of the activity requirements in uplink and downlink for a certain UE, the regular DRX period including a certain planned on time can be set. The general concept of RRC connected mode DRX is illustrated in below:

An inactive timer is started after each period of activity. This timer defines the number of consecutive inactive subframes which the UE must experience before using DRX mode. The timer is stopped and re-started if there is any activity while it is running. The UE monitors the PDCCH continuously while the inactivity timer is running. Assuming the inactivity timer expires, there is an optional period of short DRX cycles. Short DRX cycles can be used initially because in general, the probability of further activity is greater during the time window immediately after any previous activity. eNB instructs the UE whether or not it should use the period of short DRX cycle. If short DRX cycles are not used then the period of long DRX cycles starts directly. Samsung eNB uses the long DRX cycles only by default, because the short DRX procedure can be a burden on signaling comparing the effectiveness of saving UE power. The eNB can instruct the UE to enter short DRX mode immediately using the DRX Command MAC control element. The DRX Command MAC control element does not have any payload. It is signaled simply by sending a DL-SCH MAC subheader with the Logical Channel Identity (LCID) set to 11110. Also, it is noted that UE in RRC connected mode are required to complete handovers when eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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moving from one cell to another. In this case, UE must exit DRX to send an uplink RRC: measurement Report message when the signal strength from a neighboring cell becomes sufficiently strong to trigger a handover. Long DRX Command is applied for delay tolerant devices like MTC. When data transmission for a delay tolerant logical channels is ongoing, for which Long DRX would be enough, short DRX would still be followed for the duration of the drxShortCycleTimer. This increases PDCCH monitoring and periodical CQI/SRS transmission unnecessarily and drains the battery. Long DRX Command MAC CE is introduced which stops the onDurationTimer, drx-InactivityTimer, drxShortCycleTimer, and enforces the UE to use Long DRX Cycle. The eNB can instruct the UE to enter Long DRX mode immediately using the DRX Command MAC control element. The DRX Command MAC control element does not have any payload. It is signaled simply by sending a DL-SCH MAC subheader with the Logical Channel Identity (LCID) set to 11010.

Long DRX Command MAC CE Trigger Condition If MTC UE doesn't have frequent activity or MTC UE with higher mobility, Long DRX Command MAC CE can be applied. In this case, Handover signaling can be avoided. If the Expected HO Interval is small is set to 'sec15' or Expected IDLE period is long set to '181' in the Expected UE Behavior IE sent from MME to eNB, eNB based on the Operator Configurations sends Long DRX Command MAC CE to the UE.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to active this feature. Activation Procedure Run CHG-DRX-INF and set DRX_CONFIG_SETUP to enable Active DRX (LongDRX, shortDRX (optional)). When ON_DURATION_TIMER_NORMAL or DRX_INACTIVITY_TIMER_NORMAL parameter is set to high, the portion of time that a UE keep awake is increased and thus the effect of power saving for the UE is reduced. Parameters for Active DRX are separated according to QCI type. In case a UE opens multiple radio bearer with different QCI type, those parameters of highest QCI priority is used.


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In case of VoLTE (QCI type 1), it is recommended to set the parameters for Active DRX is set carefully to be aligned with the period of VoLTE traffic. Recommended Active DRX parameter for QCI type 1 is 20 ms for DRX Cycle and psf10 for ON_DURATION_TIMER_NORMAL. Deactivation Procedure Run CHG-DRX-INF and set DRX_CONFIG_SETUP to disable Active DRX.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-DRX-INF/RTRV-DRX-INF. Parameter

Description

DRX_CONFIG_SETUP

This parameter indicates whether to use the DRX. Release: DRX is not used. Setup: normal DRX profile is used in the normal status and reportCGI DRX profile is used in reportCGI status. reportCGI: DRX is not used in the normal status and reportCGI DRX profile is used in reportCGI status.

SHORT_DRXCONFIG_SET UP

This parameter indicates whether to use the Short DRX mode. ci_Config_Release: Short DRX is not used. ci_Config_Setup: Short DRX is used.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-DRX-INF/RTRV-DRX-INF. Parameter

Description

PLMN_IDX

It is corresponded to the value of the same plmnIdx of PLDEnbPlmnInf. (In other words, it is the PLMN ID corresponding to PLMN index that is set in PLDEnbPlmnInfo (RTRV/CHG-ENBPLMN-INFO).

QCI

QCI(QoS Class Identifier) index. The range is from 0 to 255. The standard QCIs defined in the standard documents is 1 to 9. The user can use QCI values 0 and 10-255.

ON_DURATION_TIMER_N ORMAL

Timer to monitor PDCCH in DRX mode in normal status. (5.7 in 3GPP TS 36.321) Value in number of PDCCH sub-frames:psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on (6.3.2 in 3GPP TS 36.331) {psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20, psf30, psf40, psf50, psf60, psf80, psf100, psf200}

DRX_INACTIVITY_TIMER_ NORMAL

Timer to monitor PDCCH in DRX mode in normal status. (5.7 in 3GPP TS 36.321) Value in number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on (6.3.2 in 3GPP TS 36.331) {psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20, psf30, psf40,psf50, psf60, psf80, psf100,


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Description psf200, psf300, psf500, psf750, psf1280, psf1920, psf2560, spare10, spare9, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare1}

DRX_RETRANSMISSION_T IMER_NORMAL

The timer used to monitor PDCCH in DRXmode in normal status. {psf1, psf2, psf4, psf6, psf8, psf16, psf24, psf33}

LONG_DRXCYCLE_START _OFFSET_TYPE_NORMAL

The long DRX cycle and drx start offset values to run onDurationTimer in DRX mode in normal status. The unit of the long DRX cycle is a sub-frame. If the short DRXCycle is set to a value, this parameter is set to a multiple of the short DRX-Cycle. The DRX start offset is set to an integer. For the TDD, DL subframe or UL sub-frame can be set. {sf10, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf256, sf320, sf512, sf640, sf1024, sf1280, sf2048, sf2560} Available Value: multiple of 10ms

SHORT_DRXCYCLE_NOR MAL

The short DRX cycle to run onDuration-Timer in DRX mode in normal status. {sf2, sf5, sf8, sf10, sf16, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf256, sf320, sf512, sf640} Available Value: multiple of 10ms

DRX_SHORT_CYCLE_TIM ER_NORMAL

The timer used to enter long DRX mode in normal status

DRX_SELECTION_ORDER

Selection order per QCI to select DRX profile.

ON_DURATION_TIMER_R EPORT_CGI

Timer to monitor the PDCCH in DRX mode when intra-LTE reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on. Defined values in specification (36.331): {psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20, psf30, psf40, psf50, psf60, psf80, psf100, psf200}.

DRX_INACTIVITY_TIMER_ REPORT_CGI

Timer to monitor PDCCH in DRX mode when intra-LTE reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on. Defined values in specification (36.331): {psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20, psf30, psf40, psf50, psf60, sf80, psf100, psf200, psf300, psf500, psf750, psf1280, sf1920, psf2560, spare10, spare9, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare1}.

DRX_RETRANSMISSION_T IMER_REPORT_CGI

The timer used to monitor PDCCH in DRX mode when intra-LTE reportCGI status. Defined values in specification (36.331): {psf1, psf2, psf4, psf6, psf8, psf16, psf24, psf33}

LONG_DRXCYCLE_START _OFFSET_TYPE_REPORT _CGI

The long DRX cycle and drx start offset values to run onDurationTimer in DRX mode when intra-LTE reportCGI status. The unit of the long DRX cycle is a sub-frame. The DRX start offset is set to an integer. For the TDD, DL subframe or UL sub-frame can be set. Defined values in specification (36.331): {sf10, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf256, sf320, sf512, sf640, sf1024, sf1280, sf2048, sf2560}.

ON_DURATION_TIMER_IN TER_RAT

Timer to monitor the PDCCH in DRX mode when inter-RAT reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on. Defined values in specification (36.331): {psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20, psf30, psf40, psf50, psf60, psf80, psf100, psf200}.

DRX_INACTIVITY_TIMER_I NTER_RAT

Timer to monitor PDCCH in DRX mode when inter-RAT reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on. Defined values in specification (36.331): Enumerated{psf1, psf2, psf3, psf4, psf5, psf6, psf8, sf10, psf20, psf30, psf40, psf50, psf60, psf80, psf100, psf200, psf300, psf500, psf750, psf1280, psf1920, psf2560, spare10, spare9, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare1}.

DRX_RETRANSMISSION_T IMER_INTER_RAT

The timer used to monitor PDCCH in DRX mode when inter-RAT reportCGI status. Defined values in specification (36.331): {psf1, psf2, psf4, psf6, psf8, psf16, psf24, psf33}

LONG_DRXCYCLE_START

The long DRX cycle and drx start offset values to run onDurationTimer in DRX


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Chapter 6 Radio Scheduler Parameter _OFFSET_TYPE_INTER_R AT

Description mode when inter-RAT reportCGI status. The unit of the long DRX cycle is a sub-frame. The DRX start offset is set to an integer. For the TDD, DL subframe or UL sub-frame can be set. Defined values in specification (36.331): {sf10, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf256, sf320, sf512, sf640, sf1024, sf1280, sf2048, sf2560}.


Type Name

Type Description

Active DRX

DrxActAtt

Counted when eNB has sent the RRCConnectionReconfiguration message including Active DRX Setup to VoLTE UE.

DrxActSucc

Counted when eNB has received the RRCConnectionReconfigurationComplete message for the Active DRX Setup request from VoLTE UE.

DrxDeactAtt

Counted when eNB has sent the RRCConnectionReconfiguration message including Active DRX Release to VoLTE UE.

DrxDeactSucc

Counted when eNB has received the RRCConnectionReconfigurationComplete message for the Active DRX Release request from VoLTE UE.

DrxNoAvg

The number of active DRX activated VoLTE UEs is counted every 2 seconds.


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [3] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification


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LTE-ME3503, CFI-based PUSCH adaptation INTRODUCTION The PUCCH resources are allocated in the edge of the system bandwidth, and a number of PUCCH resources become overhead to reduce an uplink throughput. Among PUCCH resources, format 1a/1b resources for HARQ-ACK are mapped to Control Channel Elements (CCEs) in downlink subframe. Because a number of CCEs depends on Control Format Indicator (CFI), a number of PDCCH symbols and a number of PUCCH resources for HARQ-ACK also depend on CFI. This feature enables uplink scheduler allocates a number of PUSCH RBs according to the change of PUCCH HARQ-ACK resources by CFI change.

BENEFIT The uplink peak throughput can be achieved while PDCCH symbols are flexibly changed.

DEPENDENCY AND LIMITATION Limitation This feature is supported in TDD 20 MHz bandwidth only.

This feature is operated in PUCCH state 0 only.

FEATURE DESCRIPTION The PUCCH is used to transfer Uplink Control Information (UCI). A Number of PUCCH resources is the sum of number of resources for format 1/1a/1b and that for format 2. The PUCCH format 1/1a/1b includes Scheduling Request (SR) and HARQ-ACK. HARQ-ACK can be separated as Semi-Persistent Scheduling (SPS) and PDCCH based scheduling. The locations of each PUCCH resources are shown in the below figure, where CQI is located in the edge of system bandwidth. SPS HARQ-ACK and SR is located inside of CQI, where the number of SPS HARQ-ACK and SR is determined by higher-layer RRC parameter N(1)PUCCH. The position of HARQACK by PDCCH based scheduling is nearest to PUSCH region.


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SR resources and SPS HARQ-ACK resources are allocated per UE dedicatedly, but HARQ-ACK resources according to PDCCH based scheduling are mapped to PDCCH CCE indices of the corresponding downlink transmission. PUCCH HARQ-ACK resource index is calculated as follows:

FDD: N(1)PUCCH + nCCE TDD: N(1)PUCCH + (M-m-1) x N(p) + m x N(p + 1) + nCCE In the above formula, N(1)PUCCH is the number of resources reserved for SPS HARQ-ACK and SR. nCCE is PDCCH CCE index of the corresponding downlink transmission. In TDD, HARQ-ACKs for multiple downlink subframes are bundled in one uplink subframe, so PUCCH HARQ-ACK resources are multiplied by a number of bundled downlink subframes. M is the number of downlink bundled subframes and m is the subframe index where the PDCCH CCE index is mapped to HARQACK. M is two for UL/DL Configuration #1 and four for UL/DL Configuration #2. The following figure shows HARQ-ACK resource allocation for TDD UL/DL Configuration #2:

In the above figure, the position of HARQ-ACK resource depends on CCE index and PDSCH subframe index, and can be separated by CFI. This means some HARQ-ACK resources are not used when the corresponding downlink subframe uses small number of PDCCH symbols. Because positions of PUCCH HARQ-ACK resources are close to PUSCH region, unused RBs for PUCCH HARQ-ACK can be used for PUSCH transmission. Hence, uplink throughput can be increased by restricting CFI and reducing HARQ-ACK resources, especially in TDD. Another way is to change a maximum number of PUSCH RBs dynamically based on CFI as below figure. By flexibly changing the number of PUSCH RBs, uplink throughput can be maintained while adapting a number of PDCCH symbol.


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When this feature is enabled, Samsung eNB reduces frequency of changing PDCCH symbol because CFI increase makes PUSCH RBs be smaller, where PUSCH retransmission may be not transmitted. So, CFI increase needs to wait until all uplink retransmission is transmitted. This feature is only applied in PUCCH state 0 in TDD 20 MHz by following reason:

A number of HARQ-ACK resources in TDD is much more than FDD. Hence, this feature is more effective for TDD than FDD.

The side effect of this feature, the reduction of frequency of changing PDCCH symbol, may influence the number of PDCCH allocation failure in large number of UEs. This side effect can be reduced if there are a lot of CCEs per CFI as 20 MHz bandwidth.

SYSTEM OPERATION How to Activate The operator can activate of deactivate this feature by setting the parameter CFI_PUSCH_ALLOC_ENABLE in PLD. Turn ON

PuschConfIdle::CFI_PUSCH_ALLOC_ENABLE = 1

Turn Off

PuschConfIdle::CFI_PUSCH_ALLOC_ENABLE = 0

Key Parameter RTRV-PUSCH-IDLE/CHG-PUSCH-IDLE Parameter

Description

CFI_PUSCH_ALLOC_ENABLE

This parameter is used to enable this feature. 0: This feature is not used. 1: This feature is used.

Counters and KPIs There is no related counter or KPI. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 7

Radio Transmission

LTE-ME0102, FDD 3 MHz Bandwidth INTRODUCTION In the LTE system, total six channel bandwidths are standardized in 3GPP specification: 1.4, 3, 5, 10, 15, and 20 MHz channel bandwidth. In this feature, it is described of 3 MHz channel bandwidth configuration, which is composed of total 15 resource block (RB). 1 RB is 180 kHz frequency spacing, and actually the bandwidth of 2.7 MHz is used for transmission except for guard bandwidth. Therefore, the spectral efficiency is 90 % for 3 MHz channel bandwidth configuration.

BENEFIT The operator can support the LTE service with channel bandwidth of 3 MHz.

DEPENDENCY None

LIMITATION None

FEATURE DESCRIPTION 3GPP has specified a set of six channel bandwidths, ranging from 1.4 MHz to 20 MHz. These are presented in table below. Parameter


3 MHz

5 MHz

10 MHz

15 MHz

20 MHz

Number of Resource Blocks

6

15

25

50

75

100

Number of Subcarriers

72

180

300

600

900

1200

Figure below depicts the definition of channel bandwidth and transmission bandwidth configurations for one E UTRA carrier.


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Chapter 7 Radio Transmission

A Resource Block (RB) represents the basic unit of resource for LTE airinterface. The eNB scheduler allocates RBs to UE when allowing data transfer.

The subcarriers belong to Orthogonal Frequency Division Multiple Access (OFDMA) technology in downlink, and Single Carrier Frequency Division Multiple Access (SC-FDMA) technology in uplink.

There are 12 subcarriers per RB so the number of subcarriers equals 12 x number of RBs.

Each subcarrier occupies 15 kHz so the total subcarrier bandwidth equals 15 kHz x number of subcarriers.

The downlink subcarrier bandwidth includes an additional 15 kHz to accommodate a null subcarrier at the center of all other subcarriers. The null subcarrier provides 15 kHz of empty spectrum within which noting is transmitted.

The total subcarrier bandwidth is less than the channel bandwidth to allow for the roll-off of emissions and to provide some guard band.

The larger channel bandwidths provide support for the higher throughputs. Smaller channel bandwidths provide support for lower throughputs but are easier to accommodate within existing spectrum allocations.

3GPP also specifies a subcarrier spacing of 7.5 kHz (in addition to the subcarrier spacing of 15 kHz). The subcarrier spacing of 7.5 kHz is only used in cells, which are dedicated to Multimedia Broadcast Multicast Services (MBMS). There are 24 rather than 12 carriers per RB when using 7.5 kHz subcarrier spacing so the total bandwidth of a RB remains the same. Figure below depicts a time-frequency resource structure in 3 MHz channel bandwidth LTE system.


567


The time-frequency resources are subdivided according to the following structure:

The largest unit of time is the 10 ms radio frame, which is further subdivided into ten 1 ms subframes, each of which is split into two 0.5 ms slots.

Each slot comprises seven OFDM symbols in the case of the normal cyclic prefix length or six if the extended cyclic prefix is configured in the cell. In frequency domain, resources are grouped in units of 12 subcarriers (thus occupying a total of 180 kHz), such that one unit of 12 subcarriers for duration of one slot is termed a Resource Block (RB). The smallest unit of resource is Resource Element (RE), which consists of one subcarrier for duration of one OFDM symbol. Thus, a RB is comprised of 84 REs in the case of normal cyclic prefix length.

SYSTEM OPERATION How to Activate Run RTRV-CELL-IDLE to retrieve both DL and UL bandwidths used by an operating cell.


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Key Parameters RTRV-CELL-IDLE Parameter

Description

CELL_NUM


PHY_CELL_ID

This parameter is the Physical cell ID. It is used to allow the UE to identify the cell in a radio section, and to recover the cell specific reference signal. It should be allocated to avoid conflict between neighbor cells.

CELL_TYPE

This parameter is the type that is operating the cell: macroCell: Operates many normal cells. openCell: Operates a single normal cell. hybridCell: Operates CSG cells as well as normal cells. csgCell: Operates only Closed Subscriber Group (CSG) cells.

DUPLEX_TYPE

This parameter is the communication method that is used while operating the cell: FDD: Frequency Division Duplex TDD: Time Division Duplex

DL_ANT_COUNT


UL_ANT_COUNT

This parameter is the number of Rx antennas used by an operating cell.

EARFCN_DL

This parameter is the downlink absolute radio frequency channel number (ARFCN) used in the evolved universal terrestrial radio access network (E-UTRAN) system of an operating cell. The center frequency must be changed to E-UTRA absolute radio frequency channel number (EARFCN). [Related Specifications] Refer to 3GPP TS 36.101, 5.7.3.

EARFCN_UL

This parameter is the Uplink ARFCN used in the E-UTRAN system of an operating cell. The center frequency must be changed to EARFCN. [Related Specifications] Refer to 3GPP TS 36.101, 5.7.3.

DL_BANDWIDTH

This parameter is the downlink bandwidth used by an operating cell: 1.4 MHz: 1.4 MHz bandwidth that uses 6 Physical RBs. 3 MHz: 3 MHz bandwidth that uses 15 physical RBs. 5 MHz: 5 MHz bandwidth that uses 25 physical RBs. 10 MHz: 10 MHz bandwidth that uses 50 physical RBs. 15 MHz: 15 MHz bandwidth that uses 75 physical RBs. 20 MHz: 20 MHz Bandwidth that uses 100 physical RBs.

UL_BANDWIDTH

This parameter is the uplink bandwidth used by an operating cell. 1.4 MHz: 1.4 MHz bandwidth that uses 6 Physical RBs. 3 MHz: 3 MHz bandwidth that uses 15 physical RBs. 5 MHz: 5 MHz bandwidth that uses 25 physical RBs. 10 MHz: 10 MHz bandwidth that uses 50 physical RBs. 15 MHz: 15 MHz bandwidth that uses 75 physical RBs. 20 MHz: 20 MHz Bandwidth that uses 100 physical RBs.

FREQUENCY_BAND_INDICATO R

This parameter is the frequency band indicator information, which is about where the frequency of an operating cell is located. This information is broadcasted to the UE through SIB 1.

GROUP_ID

This parameter is the Group ID of the carrier where the cell belongs.

FORCED_MODE

This parameter indicates whether to change the configuration regardless of the cell status. False: Set the value considering the cell status.


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Chapter 7 Radio Transmission Parameter

Description True: Set the value without considering the cell status.

DL_CRS_PORT_COUNT

This parameter is the number of downlink CRS ports that are supported by the system.


REFERENCE [1] 3GPP TS 36.101: Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception [2] 3GPP TS 36.104: Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) radio transmission and reception [3] 3GPP TS 36.211: Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [4] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


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LTE-ME0103, FDD 5 MHz Bandwidth INTRODUCTION In the LTE system, total 6 channel bandwidths are standardized in 3GPP specification: 1.4, 3, 5, 10, 15 and 20 MHz channel bandwidth. In this feature, it is described of 5 MHz channel bandwidth configuration, which is composed of total 25 Resource Block (RB). 1 RB is 180 kHz frequency spacing, and actually the bandwidth of 4.5 MHz is used for transmission except for guard bandwidth. Therefore, the spectral efficiency is 90 % for 5 MHz channel bandwidth configuration.

BENEFIT The operator can support the LTE service with channel bandwidth of 5 MHz.

DEPENDENCY None

LIMITATION None

FEATURE DESCRIPTION 3GPP has specified a set of six channel bandwidths, ranging from 1.4 MHz to 20 MHz. These are presented in table below. Parameter


3 MHz

5 MHz

10 MHz

15 MHz

20 MHz


6

15

25

50

75

100


72

180

300

600

900

1200

Figure below depicts the definition of channel bandwidth and transmission bandwidth configurations for one E UTRA carrier.


571


A Resource Block represents the basic unit of resource for LTE air-interface. The eNB scheduler allocates Resource blocks to UE when allowing data transfer.

The subcarriers belong to Orthogonal Frequency Division Multiple Access (OFDMA) technology in downlink, and Single Carrier Frequency Division Multiple Access (SC-FDMA) technology in the uplink.

There are 12 subcarriers per RB so the number of subcarriers equals 12 x number of RBs.





3GPP also specifies a subcarrier spacing of 7.5 kHz (in addition to the subcarrier spacing of 15 kHz). The subcarrier spacing of 7.5 kHz is only used in cells, which are dedicated to Multimedia Broadcast Multicast Services (MBMS). There are 24 rather than 12 carriers per RB when using 7.5 kHz subcarrier spacing so the total bandwidth of a Resource Block remains the same. Figure below depicts a time-frequency resource structure in 5 MHz channel bandwidth LTE system.


572


The time-frequency resources are subdivided according to the following structure:

The largest unit of time is the 10 ms radio frame, which is further subdivided into ten 1 ms subframes, each of which is split into two 0.5 ms slots.

Each slot comprises seven OFDM symbols in the case of the normal cyclic prefix length or six if the extended cyclic prefix is configured in the cell. In frequency domain, resources are grouped in units of 12 subcarriers (thus occupying a total of 180 kHz), such that one unit of 12 subcarriers for duration of one slot is termed a Resource Block (RB). The smallest unit of resource is Resource Element (RE), which consists of one subcarrier for duration of one OFDM symbol. Thus, a resource block is comprised of 84 resource elements in the case of normal cyclic prefix length.

SYSTEM OPERATION How to Activate 1 Lock the cell in LSM eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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2 Run CHG-CELL-IDLE and set the value of DL_BANDWIDTH and UL_BANDWIDTH to an appropriate bandwidth.

3 Select 5 MHz at DL_BANDWIDTH and UL_BANDWIDTH respectively. 4 Unlock the cell in LSM. Key Parameters RTRV-CELL-IDLE Parameter

Description

CELL_NUM


PHY_CELL_ID

This parameter is the Physical cell ID. It is used to allow the UE to identify the cell in a radio section, and to recover the cell specific reference signal. It should be allocated to avoid conflict between neighbor cells.

CELL_TYPE

This parameter is the type that is operating the cell: macroCell: Operates many normal cells. openCell: Operates a single normal cell. hybridCell: Operates CSG cells as well as normal cells. csgCell: Operates only Closed Subscriber Group (CSG) cells.

DUPLEX_TYPE

This parameter is the communication method that is used while operating the cell: FDD: Frequency Division Duplex. TDD: Time Division Duplex.

DL_ANT_COUNT


UL_ANT_COUNT

This parameter is the number of Rx antennas used by an operating cell.

EARFCN_DL

This parameter is the downlink absolute radio frequency channel number (ARFCN) used in the evolved universal terrestrial radio access network (E-UTRAN) system of an operating cell. The center frequency must be changed to E-UTRA absolute radio frequency channel number (EARFCN). [Related Specifications] Refer to 3GPP TS 36.101, 5.7.3.

EARFCN_UL

This parameter is the Uplink ARFCN used in the E-UTRAN system of an operating cell. The center frequency must be changed to EARFCN. [Related Specifications] Refer to 3GPP TS 36.101, 5.7.3.

DL_BANDWIDTH

This parameter is the downlink bandwidth used by an operating cell: 1.4 MHz: 1.4 MHz bandwidth that uses 6 Physical RBs. 3 MHz: 3 MHz bandwidth that uses 15 physical RBs. 5 MHz: 5 MHz bandwidth that uses 25 physical RBs. 10 MHz: 10 MHz bandwidth that uses 50 physical RBs. 15 MHz: 15 MHz bandwidth that uses 75 physical RBs. 20 MHz: 20 MHz Bandwidth that uses 100 physical RBs.

UL_BANDWIDTH

This parameter is the uplink bandwidth used by an operating cell. 1.4 MHz: 1.4 MHz bandwidth that uses 6 Physical RBs. 3 MHz: 3 MHz bandwidth that uses 15 physical RBs. 5 MHz: 5 MHz bandwidth that uses 25 physical RBs. 10 MHz: 10 MHz bandwidth that uses 50 physical RBs. 15 MHz: 15 MHz bandwidth that uses 75 physical RBs. 20 MHz: 20 MHz Bandwidth that uses 100 physical RBs.


574


Description

FREQUENCY_BAND_INDICATO R

This parameter is the frequency band indicator information, which is about where the frequency of an operating cell is located. This information is broadcasted to the UE through SIB 1.

GROUP_ID

This parameter is the Group ID of the carrier where the cell belongs.

FORCED_MODE

This parameter indicates whether to change the configuration regardless of the cell status. False: Set the value considering the cell status. True: Set the value without considering the cell status.

DL_CRS_PORT_COUNT

This parameter is the number of downlink CRS ports that are supported by the system.




575


LTE-ME0107, TDD 20 MHz Bandwidth INTRODUCTION In Frequency Division Duplexing (FDD), LTE uses a paired spectrum for uplink and downlink, but TD-LTE uses a different approach, a single frequency sharing the channel between transmission and reception, spacing them apart by multiplexing the two signals on a real time basis. While FDD transmissions require a guard band between the transmitter and receiver frequencies, Time Division Duplexing (TDD) schemes require a guard time or guard interval between transmission and reception. The LTE system supports variable channel bandwidth and, total six channel bandwidths are standardized in 3GPP specification: 1.4, 3, 5, 10, 15, and 20 MHz channel bandwidth. In this feature, it is described of TDD 20 MHz channel bandwidth configuration, which is composed of total 100 resource blocks.

BENEFIT The operator can support TDD LTE service with most general TDD channel bandwidth of 20 MHz.

DEPENDENCY None

LIMITATION TDD Only

FEATURE DESCRIPTION The TDD duplex mode is used for transmission in unpaired frequency band. According to the 3GPP specification 36.104, E-UTRA is designed to operate in the operating bands defined in table below for TDD configuration. E-UTRA Operating Band

UL Operating Band

DL Operating Band

Duplex Mode

33

1900 MHz-1920 MHz

1900 MHz-1920 MHz

TDD

34

2010 MHz-2025 MHz

2010 MHz-2025 MHz

TDD

35

1850 MHz-1910 MHz

1850 MHz-1910 MHz

TDD

36

1930 MHz-1990 MHz

1930 MHz-1990 MHz

TDD

37

1910 MHz-1930 MHz

1910 MHz-1930 MHz

TDD

38

2570 MHz-2620 MHz

2570 MHz-2620 MHz

TDD

39

1880 MHz-1920 MHz

1880 MHz-1920 MHz

TDD


576

Chapter 7 Radio Transmission E-UTRA Operating Band

UL Operating Band

DL Operating Band

Duplex Mode

40

2300 MHz-2400 MHz

2300 MHz-2400 MHz

TDD

41

2496 MHz-2690 MHz

2496 MHz-2690 MHz

TDD

42

3400 MHz-3600 MHz

3400 MHz-3600 MHz

TDD

43

3600 MHz-3800 MHz

3600 MHz-3800 MHz

TDD

44

703 MHz-803 MHz

703 MHz-803 MHz

TDD

3GPP has specified a set of six channel bandwidths, ranging from 1.4 MHz to 20 MHz. These are presented in table below. Parameter


3 MHz

5 MHz

10 MHz

15 MHz

20 MHz


6

15

25

50

75

100


72

180

300

600

900

1200

A Resource Block (RB) represents the basic unit of resource for LTE airinterface. The eNB scheduler allocates resource blocks to UE when allowing data transfer. In 20 MHz channel bandwidth, the total number of RBs is 100.

The subcarriers belong to Orthogonal Frequency Division Multiple Access (OFDMA) technology in downlink, and Single Carrier Frequency Division Multiple Access (SC-FDMA) technology in uplink.

There are 12 subcarriers per RB so the number of subcarriers equals 12 x number of RBs. Therefore, the number of subcarriers is 1200 in 20 MHz channel bandwidth.





SYSTEM OPERATION How to Activate Run RTRV-CELL-IDLE to retrieve both DL_BANDWIDTH and UL_BANDWIDTH used by an operating cell.


577


Key Parameters RTRV-CELL-IDLE/CHG-CELL-IDLE Parameter

Description

CELL_NUM


PHY_CELL_ID

Physical cell ID. It is used for UE to distinguish the cell in a wireless network, and is also used to recover cell-specific reference signals. It should be assigned to avoid conflicts between neighboring cells.

CELL_TYPE

Type of cell operation: macroCell: Operates multiple common cells. openCell: Operates a single common cell. hybridCell: Operates closed subscriber group (CSG) cells as well as common ones. csgCell: Operates CSG cells only.

DUPLEX_TYPE

Communication method for cell operation: ci_FDD: Frequency division duplex. ci_TDD: Time division duplex.

DL_ANT_COUNT

Tx antenna count used by the active cell: ci_n1TxAntCnt: 1 Tx antenna is used. ci_n2TxAntCnt: 2 Tx antennas are used. ci_n4TxAntCnt: 4 Tx antennas are used.

UL_ANT_COUNT

The Rx antenna count used by the active cell: ci_n2RxAntCnt: 2 Rx antennas are used. ci_n4RxAntCnt: 4 Rx antennas are used. ci_n6RxAntCnt: 6 Rx antennas are used. ci_n8RxAntCnt: 8 Rx antennas are used. ci_n10RxAntCnt: 10 Rx antennas are used. ci_n12RxAntCnt: 12 Rx antennas are used.

EARFCN_DL

Downlink Absolute Radio Frequency Channel Number (ARFCN) used by the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) system in the active cell. The center frequency should be changed to E-UTRA Absolute Radio Frequency Channel Number (EARFCN). See 5.7.3 in 3GPP TS 36.101.

EARFCN_UL

Uplink ARFCN used by the E-UTRAN system in the active cell. The center frequency should be changed to EARFCN. See 5.7.3 in 3GPP TS 36.101.

DL_BANDWIDTH

Downlink bandwidth used by the active cell: ci_SystemBandwidth_n6: 1.4 MHz bandwidth that uses 6 physical RBs. ci_SystemBandwidth_n15: 3 MHz bandwidth that uses 15 physical RBs. ci_SystemBandwidth_n25: 5 MHz bandwidth that uses 25 physical RBs. ci_SystemBandwidth_n50: 10 MHz bandwidth that uses 50 physical RBs ci_SystemBandwidth_n75: 15 MHz bandwidth that uses 75 physical RBs. ci_SystemBandwidth_n100: 20 MHz bandwidth that uses 100 physical RBs.

UL_BANDWIDTH

Uplink bandwidth used by the active cell: ci_SystemBandwidth_n6: 1.4 MHz bandwidth that uses 6 physical RBs. ci_SystemBandwidth_n15: 3 MHz bandwidth that uses 15 physical RBs. ci_SystemBandwidth_n25: 5 MHz bandwidth that uses 25 physical RBs. ci_SystemBandwidth_n50: 10 MHz bandwidth that uses50 physical RBs. ci_SystemBandwidth_n75: 15 MHz bandwidth that uses 75 physical RBs. ci_SystemBandwidth_n100: 20 MHz bandwidth that uses 100 physical RBs.

FREQUENCY_

Frequency band indicator including the frequency of the active cell.


578

Chapter 7 Radio Transmission Parameter BAND_INDICATOR

Description This information is broadcast to UE via SIB 1.

GROUP_ID

This parameter defines Carrier groupId for the cell

FORCED_MODE

Whether to set the PLD change regardless of the cell status. False: The PLD change is set according to the cell status. True: The PLD change is set regardless of the cell status.

DL_CRS_PORT _COUNT

This parameter defines Downlink CRS Port Count




579


LTE-ME0201, Frame Structure Type 1 (FDD) INTRODUCTION The frame structure considers only the time domain. 3GPP TS 36.211 specifies frame structure Type 1 and Type2. The Type 1 frame structure is applicable to FDD (both full and half-duplex), whereas Type 2 frame structure is applicable to TDD. In both cases, radio frames are numbered using their System Frame Number (SFN). The transmission resource consists of a consecutive radio frame. Each radio frame is composed of 10 subframes with 1ms length and each subframe is composed of two slots, that is, totally radio frame is a composition of 20 slots indexed 0 to 19. Each slot has duration of 0.5 ms. Downlink and uplink transmission of a radio frame is divided in frequency domain.

BENEFIT The operator can support FDD-LTE service.

DEPENDENCY None

LIMITATION FDD Only

FEATURE DESCRIPTION The Type 1 frame structure is applicable to half-duplex FDD. Figure below depicts the Type 1 frame structure.

The smallest one is called a slot, which is of length Tslot = 0.5 ms.


580


Two consecutive slots are defined as a subframe of length one ms, and 20 slots, numbered from 0 to 19, constitute a radio frame of 10ms. Channel-dependent scheduling and link adaptation operate on a subframe level. Therefore, the subframe duration corresponds to the minimum downlink TTI, which is of one ms duration, compared to a 2 ms TTI for the HSPA and a minimum 10 ms TTI for the UMTS. A shorter TTI for fast link adaptation and is able to reduce delay and better exploit the time varying channel through channel dependent scheduling. Each slot consists of a number of OFDM symbols including CPs. CP is a kind of guard interval to combat inter-OFDM-symbol interference, which should be larger than the channel delay spread. Therefore, the length of CP depends on the environment where the network operates, and it should not be too large as it brings a bandwidth and power penalty. With a subcarrier spacing Δf = 15 kHz, the OFDM symbol time is 1/Δf ≈ 66.7 us. The LTE defines two different CP lengths:

Normal CP Extended CP A normal CP and an extended CP correspond to seven and six OFDM symbols per slot, respectively. The extended CP is for multicell multicast/broadcast and very large cell scenarios with large delay spread at a price of bandwidth efficiency, with length 16.7 us. The normal CP is suitable for urban environment and high data rate applications. The normal CP lengths are different for the first and subsequent OFDM symbols, which is to fill the entire slot of 0.5 ms. For example, with 10 MHz bandwidth, the sampling time is 1/(15000x1024) s and the number of CP samples for the extended CP is 256, which provides the required CP length of 256/(15000x1024)≈1.67 us. In case of 7.5 kHz subcarrier spacing, there is only a single CP length, corresponding to three OFDM symbols per slot. The typical parameters for frame structure are as follows. Parameter

Transmission Bandwidth [ MHz] 1.4

3

5

10

15

20

Occupied bandwidth [ MHz]

1.08

2.7

4.5

9.0

13.5

18.0

Guard band [ MHz]

0.32

0.3

0.5

1.0

1.5

2.0

Sampling frequency [ MHz]

1.92

3.84

7.68

15.36

23.04

30.72

FFT size

128

256

512

1024

1536

2048

Number of occupied subcarriers

72

180

300

600

900

1200

Number of resource blocks

6

15

25

50

75

100

SYSTEM OPERATION How to Activate The separate activate procedure is not necessary for this feature.


581




REFERENCE [1] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [2] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


582


LTE-ME0203, Frame Structure Type 2 (UL/DL Configuration #1) INTRODUCTION 3GPP TS 36.211 specifies frame structure Type 1 and Type2. The Type 1 frame structure is applicable to FDD (both full and half-duplex), whereas Type 2 frame structure is applicable to TDD. TDD is based on using the same RF carrier for uplink and downlink transmission. The UE and eNB cannot transmit simultaneously in the case of TDD because they share the same RF carrier. TDD is attractive for systems where the data transfer is highly asymmetric because the ratio between the uplink and downlink transmission can be adjusted appropriately and the RF carrier remains fully utilised.

BENEFIT The operator can support TDD-LTE service timely multiplexed with a specific DL/UL ratio (= 4:4) in a radio frame.

DEPENDENCY None

LIMITATION TDD Only

FEATURE DESCRIPTION Figure below depicts the Type 2 frame structure.


583


In the case of TDD, each radio frame consists of two half-frames of five subframes each. A subframe can be either uplink subframe, downlink subframe, or special subframe. The special subframe includes the following field:

Downlink Pilot Time Slot (DwPTS) Guard Period (GP) Uplink Pilot Time Slot (UpPTS) Special subframes are used when switching from downlink to uplink transmission. The above figure illustrates two special subframes, but there can be either one or two special subframes within a radio frame. 3GPP has specified seven allowed combinations of uplink, downlink, and special subframes. These are presented in table below. Uplink-downlink

Downlink-to-Uplink

Subframe Number

Configuration

Switch-point Periodicity

0

1

2

3

4

5

6

7

8

9

0

5 ms

D

S

U

U

U

D

S

U

U

U

1

5 ms

D

S

U

U

D

D

S

U

U

D

2

5 ms

D

S

U

D

D

D

S

U

D

D

3

10 ms

D

S

U

U

U

D

D

D

D

D

4

10 ms

D

S

U

U

D

D

D

D

D

D

5

10 ms

D

S

U

D

D

D

D

D

D

D

6

5 ms

D

S

U

U

U

D

S

U

U

D

In uplink-downlink configuration 1, LTE service is timely multiplexed with a specific DL/UL ratio (= 4:4) in a radio frame, as described in the above table. The uplink-downlink configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. Subframe 0 and 5 are always downlink subframe. These subframes include synchronization signals and broadcast information. The configuration 0, 1, 2, and 6 have a 5 ms switching point periodicity, whereas configuration 3, 4, and 5 have a 10 ms switching point periodicity. Within the special subframe, the duration of the DwPTS, UpPTS, and GP fields can be selected to suite the cell range and any coexistence requirement. The set of allowed value is presented in the following table. The special subframe configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. The DwPTS duration are defined in terms of downlink OFDMA symbols, whereas UpPTS durations are defined in terms of downlink SC-FDMA symbols. Special Subframe Configuration

Normal Cyclic Prefix DwPTS

Guard Period

UpPTS

0

3

10

1

1

9

4

2

10

3

3

11

2


584

Chapter 7 Radio Transmission Special Subframe Configuration


Guard Period

4

12

1

5

3

9

6

9

3

7

10

2

8

11

1

UpPTS 2

The guard period is necessary to accommodate the round trip time propagation delay between the UE and eNB. In addition, the switching delay of UE and eNB, when charging from reception to transmission, is also accommodated in guard period. As described in above passage, uplink-downlink configuration information is included in SIB 1 by only TDD network. The TDD configuration specifies the Subframe Assignment and the Special Subframe Pattern. The subframe assignment represents the uplink-downlink subframe configuration, that is, the number and pattern of subframes allocated to the uplink and downlink. The Special Subframe Pattern represents the special subframe configuration, that is, the duration of the DwPTS, guard period, and UpPTS. SystemInformationBlockType1 message -- ASN1START SystemInformationBlockType1 ::= cellAccessRelatedInfo plmn-IdentityList trackingAreaCode cellIdentity cellBarred intraFreqReselection csg-Indication csg-Identity }, cellSelectionInfo q-RxLevMin q-RxLevMinOffset }, p-Max freqBandIndicator schedulingInfoList tdd-Config si-WindowLength systemInfoValueTag nonCriticalExtension OPTIONAL

SEQUENCE { SEQUENCE { PLMN-IdentityList, TrackingAreaCode, CellIdentity, ENUMERATED {barred, notBarred}, ENUMERATED {allowed, notAllowed}, BOOLEAN, CSG-Identity OPTIONAL -- Need OR SEQUENCE { Q-RxLevMin, INTEGER (1..8)

OPTIONAL

-- Need OP

P-Max OPTIONAL, -- Need OP INTEGER (1..64), SchedulingInfoList, TDD-Config OPTIONAL, -- Cond TDD ENUMERATED { ms1, ms2, ms5, ms10, ms15, ms20, ms40}, INTEGER (0..31), SystemInformationBlockType1-v890-IEs

}

The IE TDD-Config is used to specify the TDD specific physical channel configuration. TDD-Config information element -- ASN1START TDD-Config ::= subframeAssignment

SEQUENCE { ENUMERATED { sa0, sa1, sa2, sa3, sa4, sa5, sa6},


585


specialSubframePatterns

ENUMERATED { ssp0, ssp1, ssp2, ssp3, ssp4,ssp5, ssp6, ssp7, ssp8}

} -- ASN1STOP

TDD-Config field descriptions specialSubframePatterns Indicates Configuration as in TS 36.211 [21, table 4.2-1] where ssp0 point to Configuration 0, ssp1 to Configuration 1 and so on. subframeAssignment Indicates DL/UL subframe configuration where sa0 point to Configuration 0, sa1 to Configuration 1 and so on as specified in TS 36.211 [21, table 4.2-2]. One value apples for all serving cells (the associated functionality is common, that is, not performed independently for each cell)

SYSTEM OPERATION How to Activate Run CHG-CELL-IDLE to set subframeAssignment to ci_subframeAssignment_sa1.


Description

CELL_NUM


PHY_CELL_ID


CELL_TYPE

Type of cell operation. macroCell: Operates multiple common cells. openCell: Operates a single common cell. hybridCell: Operates closed subscriber group (CSG) cells as well as common ones. csgCell: Operates CSG cells only.

DUPLEX_TYPE

Communication method for cell operation. ci_FDD: Frequency division duplex. ci_TDD: Time division duplex.

subframeAssignment

TDD subframe assignment of the cell in operation. The assignment is only valid if the cell's duplex is TDD. See 4.2 of 3GPP TS 36.211 for the UL/DL configuration. ci_subframeAssignment_sa0: TDD uses UL/DL Configuration 0. ci_subframeAssignment_sa1: TDD uses UL/DL Configuration 1. ci_subframeAssignment_sa2: TDD uses UL/DL Configuration 2. ci_subframeAssignment_sa3: TDD uses UL/DL Configuration 3. ci_subframeAssignment_sa4: TDD uses UL/DL Configuration 4. ci_subframeAssignment_sa5: TDD uses UL/DL Configuration 5.


586


Description ci_subframeAssignment_sa6: TDD uses UL/DL Configuration 6.


REFERENCE [1] 3GPP TS 36.101: Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception [2] 3GPP TS 36.104: Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) radio transmission and reception [3] 3GPP TS 36.211: Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [4] 3GPP TS36.300: Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


587


LTE-ME0204, Frame Structure Type 2 (UL/DL Configuration #2) INTRODUCTION 3GPP TS 36.211 specifies frame structure Type 1 and Type2. The Type 1 frame structure is applicable to FDD (both full and half-duplex), whereas Type 2 frame structure is applicable to TDD. TDD is based on using the same RF carrier for uplink and downlink transmission. UE and eNB cannot transmit simultaneously in the case of TDD because they share the same RF carrier. TDD is attractive for systems where the data transfer is highly asymmetric because the ratio between the uplink and downlink transmission can be adjusted appropriately and the RF carrier remains fully utilised.

BENEFIT The operator can support TDD-LTE service timely multiplexed with a specific DL/UL ratio (= 6:2) in a radio frame.

DEPENDENCY None

LIMITATION TDD Only

FEATURE DESCRIPTION In the case of TDD, each radio frame consists of two half-frames of five subframes each. A subframe can be uplink subframe, downlink subframe, or special subframe. The special subframe includes the following fields:

Downlink Pilot Time Slot (DwPTS) Guard Period (GP) Uplink Pilot Time Slot (UpPTS) Special subframes are used when switching from downlink to uplink transmission. There can be either one or two special subframes within a radio frame. 3GPP has specified seven allowed combinations of uplink, downlink, and special subframes. These are presented in table below. Uplink-downlink

Downlink-to-Uplink


Subframe Number

588

Chapter 7 Radio Transmission Configuration


0

1

2

3

4

5

6

7

8

9

0

5 ms

D

S

U

U

U

D

S

U

U

U

1

5 ms

D

S

U

U

D

D

S

U

U

D

2

5 ms

D

S

U

D

D

D

S

U

D

D

3

10 ms

D

S

U

U

U

D

D

D

D

D

4

10 ms

D

S

U

U

D

D

D

D

D

D

5

10 ms

D

S

U

D

D

D

D

D

D

D

6

5 ms

D

S

U

U

U

D

S

U

U

D

In uplink-downlink configuration 2, LTE service is timely multiplexed with a specific DL/UL ratio (= 6:2) in a radio frame, as described in the above table. The uplink-downlink configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. Subframe 0 and 5 are always downlink subframe. These subframes include synchronization signals and broadcast information. The configuration 0, 1, 2, and 6 have a 5 ms switching point periodicity, whereas configuration 3, 4, and 5 have a 10 ms switching point periodicity. Within the special subframe, the duration of the DwPTS, UpPTS, and GP fields can be selected to suite the cell range and any coexistence requirement. The set of allowed value is presented in the following table. The special subframe configuration used by a cell is broadcasted in SIB 1 on BCCH. The DwPTS duration are defined in terms of downlink OFDMA symbols whereas UpPTS durations are defined in terms of downlink SC-FDMA symbols. Special Subframe Configuration


Guard Period

UpPTS

0

3

10

1

1

9

4

2

10

3

3

11

2

4

12

1

5

3

9

6

9

3

7

10

2

8

11

1

2

The guard period is necessary to accommodate the round trip time propagation delay between UE and eNB. In addition, the switching delay of UE and eNB, when charging from reception to transmission, is also accommodated in guard period.


589


As described in above passage, uplink-downlink configuration information is included in SIB 1 by only TDD network. The TDD configuration specifies the Subframe Assignment and the Special Subframe Pattern. The subframe assignment represents the uplink-downlink subframe configuration, that is, the number and pattern of subframes allocated to the uplink and downlink. The Special Subframe Pattern represents the special subframe configuration, that is, the duration of the DwPTS, guard period, and UpPTS. SystemInformationBlockType1 message -- ASN1START SystemInformationBlockType1 ::= cellAccessRelatedInfo plmn-IdentityList trackingAreaCode cellIdentity cellBarred intraFreqReselection csg-Indication csg-Identity }, cellSelectionInfo q-RxLevMin q-RxLevMinOffset }, p-Max freqBandIndicator schedulingInfoList tdd-Config si-WindowLength systemInfoValueTag nonCriticalExtension OPTIONAL

SEQUENCE { SEQUENCE { PLMN-IdentityList, TrackingAreaCode, CellIdentity, ENUMERATED {barred, notBarred}, ENUMERATED {allowed, notAllowed}, BOOLEAN, CSG-Identity OPTIONAL

-- Need OR

SEQUENCE { Q-RxLevMin, INTEGER (1..8)

-- Need OP

OPTIONAL


}

The IE TDD-Config is used to specify the TDD specific physical channel configuration. TDD-Config information element -- ASN1START TDD-Config ::= subframeAssignment specialSubframePatterns

SEQUENCE { ENUMERATED { sa0, sa1, sa2, sa3, sa4, sa5, sa6}, ENUMERATED { ssp0, ssp1, ssp2, ssp3, ssp4, ssp5, ssp6, ssp7, ssp8}

} -- ASN1STOP

TDD-Config field descriptions specialSubframePatterns Indicates Configuration as in TS 36.211 [21, table 4.2-1] where ssp0 point to Configuration 0, ssp1 to Configuration 1 and so on. subframeAssignment Indicates DL/UL subframe configuration where sa0 point to Configuration 0, sa1 to Configuration 1 and so on as specified in TS 36.211 [21, table 4.2-2]. One value apples for all serving cells (the associated functionality is common, that is, not performed independently for each cell) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

590




Description

CELL_NUM


PHY_CELL_ID


CELL_TYPE


DUPLEX_TYPE


subframeAssignment

TDD subframe assignment of the cell in operation. The assignment is only valid if the cell's duplex is TDD. See 4.2 of 3GPP TS 36.211 for the UL/DL configuration. ci_subframeAssignment_sa0: TDD uses UL/DL Configuration 0. ci_subframeAssignment_sa1: TDD uses UL/DL Configuration 1. ci_subframeAssignment_sa2: TDD uses UL/DL Configuration 2. ci_subframeAssignment_sa3: TDD uses UL/DL Configuration 3. ci_subframeAssignment_sa4: TDD uses UL/DL Configuration 4. ci_subframeAssignment_sa5: TDD uses UL/DL Configuration 5. ci_subframeAssignment_sa6: TDD uses UL/DL Configuration 6.


REFERENCE [1] 3GPP TS 36.101: Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception [2] 3GPP TS 36.104: Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) radio transmission and reception [3] 3GPP TS 36.211: Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

591


[4] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


592


LTE-ME0214, Frame Structure Type 2 (SS Configuration #5) INTRODUCTION 3GPP TS 36.211 specifies frame structure Type 1 and Type2. The Type 1 frame structure is applicable to FDD (both full and half-duplex), whereas the Type 2 frame structure is applicable to TDD. TDD is based on using the same RF carrier for uplink and downlink transmission. The UE and eNB cannot transmit simultaneously in the case of TDD because they share the same RF carrier. TDD is attractive for systems where the data transfer is highly asymmetric because the ratio between the uplink and downlink transmission can be adjusted appropriately and the RF carrier remains fully utilised.

BENEFIT The operator can support TD-LTE service with special subframe configuration 5 of DwPTS: GP:UpPTS = 3:9:2.

DEPENDENCY None

LIMITATION TDD Only



593


In the case of TDD, each radio frame consists of two half-frames of five subframes each. A subframe can be uplink subframe, downlink subframe, or special subframe. The special subframe includes the following fields:


Downlink-to-Uplink

Subframe Number

Configuration


0

1

2

3

4

5

6

7

8

9

0

5 ms

D

S

U

U

U

D

S

U

U

U

1

5 ms

D

S

U

U

D

D

S

U

U

D

2

5 ms

D

S

U

D

D

D

S

U

D

D

3

10 ms

D

S

U

U

U

D

D

D

D

D

4

10 ms

D

S

U

U

D

D

D

D

D

D

5

10 ms

D

S

U

D

D

D

D

D

D

D

6

5 ms

D

S

U

U

U

D

S

U

U

D

The uplink-downlink configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. Subframe 0 and 5 are always downlink subframe. These subframes include synchronization signals and broadcast information. The configuration 0, 1, 2, and 6 have a 5 ms switching point periodicity, whereas configuration 3, 4, and 5 have a 10 ms switching point periodicity. Within the special subframe, the duration of the DwPTS, UpPTS, and GP fields can be selected to suite the cell range and any coexistence requirement. The set of allowed value is presented in table below. The special subframe configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. The DwPTS duration are defined in terms of downlink OFDMA symbols whereas the UpPTS durations are defined in terms of downlink SC-FDMA symbols. Special Subframe Configuration


Guard Period

UpPTS

0

3

10

1

1

9

4

2

10

3

3

11

2

4

12

1

5

3

9

6

9

3


2

594



Guard Period

7

10

2

8

11

1

UpPTS

The guard period is necessary to accommodate the round trip time propagation delay between UE and eNB. In addition, the switching delay of UE and eNB, when charging from reception to transmission, is also accommodated in guard period. As described in above table, special subframe configuration 5 supports DwPTS: GP: UpPTS = 3: 9: 2. As described in above passage, uplink-downlink configuration information is included in SIB 1 by only TDD network. The TDD configuration specifies the Subframe Assignment and the Special Subframe Pattern. The subframe assignment represents the uplink-downlink subframe configuration, that is, the number and pattern of subframes allocated to the uplink and downlink. The Special Subframe Pattern represents the special subframe configuration, that is, the duration of the DwPTS, guard period, and UpPTS. SystemInformationBlockType1 message -- ASN1START SystemInformationBlockType1 ::= cellAccessRelatedInfo plmn-IdentityList trackingAreaCode cellIdentity cellBarred intraFreqReselection csg-Indication csg-Identity }, cellSelectionInfo q-RxLevMin q-RxLevMinOffset }, p-Max freqBandIndicator schedulingInfoList tdd-Config si-WindowLength systemInfoValueTag nonCriticalExtension OPTIONAL

SEQUENCE { SEQUENCE { PLMN-IdentityList, TrackingAreaCode, CellIdentity, ENUMERATED {barred, notBarred}, ENUMERATED {allowed, notAllowed}, BOOLEAN, CSG-Identity OPTIONAL

-- Need OR

SEQUENCE { Q-RxLevMin, INTEGER (1..8)

-- Need OP

OPTIONAL


}

The IE TDD-Config is used to specify the TDD specific physical channel configuration. TDD-Config information element -- ASN1START TDD-Config ::= subframeAssignment specialSubframePatterns

SEQUENCE { ENUMERATED { sa0, sa1, sa2, sa3, sa4, sa5, sa6}, ENUMERATED { ssp0, ssp1, ssp2, ssp3, ssp4,ssp5, ssp6, ssp7,


595


ssp8} } -- ASN1STOP




Description

CELL_NUM


PHY_CELL_ID


CELL_TYPE


DUPLEX_TYPE


subframeAssignment



TDD special subframe of the cell in operation. The information is only valid if the cell in operation's duplex is TDD. See 4.2 in 3GPP TS 36.211 for the special


596


Description subframe configuration. ci_specialSubframePattern_ssp0: TDD uses Special Subframe 0. ci_specialSubframePattern_ssp1: TDD uses Special Subframe 1. ci_specialSubframePattern_ssp2: TDD uses Special Subframe 2. ci_specialSubframePattern_ssp3: TDD uses Special Subframe 3. ci_specialSubframePattern_ssp4: TDD uses Special Subframe 4. ci_specialSubframePattern_ssp5: TDD uses Special Subframe 5. ci_specialSubframePattern_ssp6: TDD uses Special Subframe 6. ci_specialSubframePattern_ssp7: TDD uses Special Subframe 7. ci_specialSubframePattern_ssp8: TDD uses Special Subframe 8.


REFERENCE [1] 3GPP TS 36.101: Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception [2] 3GPP TS 36.104: Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) radio transmission and reception [3] 3GPP TS 36.211: Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [4] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2


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LTE-ME0216, Frame Structure Type 2 (SS Configuration #7) INTRODUCTION 3GPP TS 36.211 specifies frame structure Type 1 and Type2. The Type 1 frame structure is applicable to FDD (both full and half-duplex), whereas the Type 2 frame structure is applicable to TDD. TDD is based on using the same RF carrier for uplink and downlink transmission. The UE and eNB cannot transmit simultaneously in the case of TDD because they share the same RF carrier. TDD is attractive for systems where the data transfer is highly asymmetric because the ratio between the uplink and downlink transmission can be adjusted appropriately and the RF carrier remains fully utilised.

BENEFIT The operator can support TD-LTE service with special subframe configuration 7 of DwPTS: GP:UpPTS = 10:2:2.

DEPENDENCY None

LIMITATION TDD Only



598


In the case of TDD, each radio frame consists of two half-frames of five subframes each. A subframe can be uplink subframe, downlink subframe, or special subframe. The special subframe includes the following fields:


Downlink-to-Uplink

Subframe Number

Configuration


0

1

2

3

4

5

6

7

8

9

0

5 ms

D

S

U

U

U

D

S

U

U

U

1

5 ms

D

S

U

U

D

D

S

U

U

D

2

5 ms

D

S

U

D

D

D

S

U

D

D

3

10 ms

D

S

U

U

U

D

D

D

D

D

4

10 ms

D

S

U

U

D

D

D

D

D

D

5

10 ms

D

S

U

D

D

D

D

D

D

D

6

5 ms

D

S

U

U

U

D

S

U

U

D

The uplink-downlink configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. Subframe 0 and 5 are always downlink subframe. These subframes include synchronization signals and broadcast information. The configuration 0, 1, 2, and 6 have a 5 ms switching point periodicity, whereas configuration 3, 4, and 5 have a 10 ms switching point periodicity. Within the special subframe, the duration of the DwPTS, UpPTS, and GP fields can be selected to suite the cell range and any coexistence requirement. The set of allowed value is presented in table below. The special subframe configuration used by a cell is broadcast in System Information Block (SIB) 1 on BCCH. The DwPTS duration are defined in terms of downlink OFDMA symbols whereas the UpPTS durations are defined in terms of downlink SC-FDMA symbols. Special Subframe Configuration


Guard Period

UpPTS

0

3

10

1

1

9

4

2

10

3

3

11

2

4

12

1

5

3

9

6

9

3


2

599



Guard Period

7

10

2

8

11

1

UpPTS

The guard period is necessary to accommodate the round trip time propagation delay between the UE and eNB. In addition, the switching delay of UE and eNB, when charging from reception to transmission, is also accommodated in guard period. As described in above table, special subframe configuration 7 supports DwPTS: GP: UpPTS = 10: 2: 2. As described in above passage, uplink-downlink configuration information is included in SIB 1 by only TDD network. The TDD configuration specifies the Subframe Assignment and the Special Subframe Pattern. The subframe assignment represents the uplink-downlink subframe configuration, that is, the number and pattern of subframes allocated to the uplink and downlink. The Special Subframe Pattern represents the special subframe configuration, that is, the duration of the DwPTS, guard period, and UpPTS. SystemInformationBlockType1 Message -- ASN1START SystemInformationBlockType1 ::= cellAccessRelatedInfo plmn-IdentityList trackingAreaCode cellIdentity cellBarred intraFreqReselection csg-Indication csg-Identity }, cellSelectionInfo q-RxLevMin q-RxLevMinOffset }, p-Max freqBandIndicator schedulingInfoList tdd-Config si-WindowLength systemInfoValueTag nonCriticalExtension OPTIONAL

SEQUENCE { SEQUENCE { PLMN-IdentityList, TrackingAreaCode, CellIdentity, ENUMERATED {barred, notBarred}, ENUMERATED {allowed, notAllowed}, BOOLEAN, CSG-Identity OPTIONAL -- Need OR SEQUENCE { Q-RxLevMin, INTEGER (1..8)

OPTIONAL

-- Need OP


}

The IE TDD-Config is used to specify the TDD specific physical channel configuration. TDD-Config information Element -- ASN1START TDD-Config ::= subframeAssignment specialSubframePatterns

SEQUENCE { ENUMERATED { sa0, sa1, sa2, sa3, sa4, sa5, sa6}, ENUMERATED { ssp0, ssp1, ssp2, ssp3, ssp4,ssp5, ssp6, ssp7, ssp8}

}


600


-- ASN1STOP




Description

CELL_NUM


PHY_CELL_ID


CELL_TYPE


DUPLEX_TYPE


subframeAssignment



TDD special subframe of the cell in operation. The information is only valid if the cell in operation's duplex is TDD. See 4.2 in 3GPP TS 36.211 for the special subframe configuration.


601


Description ci_specialSubframePattern_ssp0: TDD uses Special Subframe 0. ci_specialSubframePattern_ssp1: TDD uses Special Subframe 1. ci_specialSubframePattern_ssp2: TDD uses Special Subframe 2. ci_specialSubframePattern_ssp3: TDD uses Special Subframe 3. ci_specialSubframePattern_ssp4: TDD uses Special Subframe 4. ci_specialSubframePattern_ssp5: TDD uses Special Subframe 5. ci_specialSubframePattern_ssp6: TDD uses Special Subframe 6. ci_specialSubframePattern_ssp7: TDD uses Special Subframe 7. ci_specialSubframePattern_ssp8: TDD uses Special Subframe 8.




602


LTE-ME0403, Uplink 64 QAM Support INTRODUCTION The UE category 5 or 8 supports 64 QAM in uplink. The 64 QAM allows six information bits per modulation symbol, which is three times and one point five times higher than that of QPSK or 16 QAM, respectively. It increases the spectral efficiency and peak data rate. However, this higher order modulation is less robust against noise and interference, thus it requires a higher SINR to meet the given Packer Error Rate (PER) requirement. In LTE system, the UE can use 64 QAM for MCS of higher than 20.

BENEFIT The 64 QAM allows the higher spectral efficiency and peak data rate than that of QPSK or 16 QAM.

DEPENDENCY The category 5, 8, or 15 of UE is required (UL 64 QAM capable UE).

LIMITATION None

FEATURE DESCRIPTION The uplink scheduler supports 64 QAM according to UE category information and the system parameter of ENABLE_SIX_FOUR_QAM.

If the parameter is set to false, scheduler does not support 64 QAM. In this case, Adaptive Modulation and Coding (AMC) operation of all UEs is same regardless of UE category information.

If the parameter is set to 'TRUE', scheduler allows 64 QAM only for 64 QAM capable UE (UE category of 5, 8, or 15). oThese UE can use 64 QAM modulation if MCS between 20 and 28 is assigned.


603


oThe 16 QAM capable UE (otherwise) can use MCS up to 24. Since there is overlapped MCS range (that is, MCS between 21 and 24), uplink scheduler limits the maximum MCS as 20 until the UE category information is obtained. It prevents the uncertainty of whether UE uses 16 QAM or 64 QAM.

SYSTEM OPERATION How to Activate This feature can be activated and deactivated with ENABLE_SIX_FOUR_QAM.

Run RTRV-PUSCH-CONF to retrieve the configuration information for ENABLE_SIX_FOUR_QAM.

Run CHG-PUSCH-CONF to change the value of ENABLE_SIX_FOUR_QAM. oDefault UL_MIMO_MODE is TRUE (ENABLE_SIX_FOUR_QAM = 1). oThe operator can disable this feature by setting ENABLE_SIX_FOUR_QAM to FALSE (ENABLE_SIX_FOUR_QAM = 0).

Key Parameters CHG-PUSCH-CONF/RTRV-PUSCH-CONF Parameter

Description

ENABLE_SIX_FOUR_QAM

0 (FALSE): Not support 1 (TRUE): Support


REFERENCE [1] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-ME3010, Timing Advance Control INTRODUCTION In the wireless system, when UEs transmit signal simultaneously, the arrival time of signal received by eNB is different due to different propagation delay between UE and eNB. This phenomenon so called near-far problem is a common issue, not just pertaining to LTE network. To make time align the transmissions from different UEs with the receiver window of eNB, eNB uses Timing Advance Command (TAC), which indicates how much time UE should advance or delay its timings of transmissions. Each UE considers the starting point of uplink radio frame is (NTA + NTA offset) x Ts ahead to that of downlink radio frame, where NTA is the value of timing advance for the corresponding UE ranging from 0 to 20512, NTA offset is 0 for FD-LTE and 624 for TD-LTE, and Ts = 1 / (15000 × 2048) seconds. The TAC can control NTA for each UE with a granularity of 16 Ts.

BENEFIT Enabling UL synchronization

DEPENDENCY None

LIMITATION None

FEATURE DESCRIPTION Uplink time alignment is maintained by continued interaction between eNB and UE through timing advance command (TAC). If UE does not receive TAC within timeAlignmentTimer, it releases HARQ buffer and PUCCH/SRS while clearing downlink assignments and uplink grants. In that case, the only possible UL transmission for UE is to send Random Access Preamble. The timeAlignmentTimer is always restarted whenever TAC is received.

Configuration of timeAlignmentTimer The timeAlignmentTimer informed by eNB can be configured to have one of the following values as defined in the standards: ENUMERATED {sf500, sf750, sf1280, sf1920, sf2560, sf5120, sf10240, infinity}


605


Where, sf represents subframe. It can be announced either SIB2 (commonly in a cell) or MAC-MainConfig (in UE specific manner).

SIB2: timeAlignmentTimerCommon MAC-MainConfig: timeAlignmentTimerDedicated Types of Timing Advance Command (TAC) The TAC used to adjust a timing of UE transmission can have two different sizes as follows:

MAC Random Access Response (RAR): 11 bits MAC Control Element (CE): 6 bits The former can indicate the timing with an absolute value while the latter represents the relative difference (that is, plus or minus around the middle of the range) compared with the old value. When UL CA is used, the timing advance control should operate with PCell and SCell, respectively. That is, multiple timing advance groups should be maintained. For this extension, please refer to the feature 'LTE-SW5503, UL CA Call Control'.

SYSTEM OPERATION How to Activate The timing advance control is always activated. Disabling this feature is not supported. Key Parameters RTRV-TIME-ALIGN/CHG-TIME-ALIGN Parameter

Description

timeAlignmentTimerCommon

This parameter is used to control how long UE is considered uplink time aligned. The value is a number of subframes.


REFERENCE [1] 3GPP TS 36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[3] 3GPP TS 36.213 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures [4] 3GPP TS 36.321 Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification [5] 3GPP TS 36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification


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SON

LTE-SO0101, Self-establishment INTRODUCTION Self establishment is to automate eNB commissioning procedure and minimize the on-site manual operation. To support Self Establishment, the following procedures need to be implemented.

1 Automatic H/W test 2 Automatic Transport Configuration(eNB OAM IP, subnet, gateway IP) and EMS IP address acquisition from DHCP server

3 Registration to EMS 4 Software update & Configuration download from EMS 5 Additional Transport Configuration (S1-C, S1-U, X2) by using downloaded configuration

BENEFIT Self-establishment of eNBs will reduce the amount of manual processes involved in the integration and configuration of new eNBs.

Self-establishment could supply a faster network deployment, reduced costs for the operator in addition to a more integral inventory management system and less human error.

DEPENDENCY Required Network Elements DHCP server

Prerequisite Features COM-IP0803 DHCP for IPv6 should be activated.

LIMITATION None

REQUIREMENT RJIL-FRD-034, Auto Static Configuration


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FEATURE DESCRIPTION When installing the LTE system, the Self Establishment function allows the eNB to perform initialization automatically to provide convenience for operation of the LTE system. This function is turned on by default.

Pre-condition oDHCP server should be configured to be able to give eNB OAM IP/netmask/gw IP address and LSM IP address. oeNB VLAN for OAM is pre-configured at the factory. oIn LSM, eNB S/N and eNB ID is pre-provisioned. The following figure is eNB Self Establishment Procedure.


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1) The eNB hardware installation is performed. 2) After power on, the eNB hardware test (Power On Self-Test) is performed. 3) eNB contacts DHCP server to get eNB IP for OAM, netmask, GW IP and LSM IP address by using pre-configured VLAN for OAM. (VLAN for OAM is preconfigured at factory.) oThe IP address of the eNB is given as a response to the DHCP request, and the LSM IP addresses is given by the option field (Option 43) of the DHCP response message. 4) The eNB sends the registration request message to the LSM. Information included in the registration request message: eNB ID (as null), eNB S/N 5) The LSM saves the eNB IP address of the eNB‟s authentication message and sends the registration response message to the eNB. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oIn registration response message, eNB ID is included. The eNB will use the received eNB ID. 6) The eNB downloads and installs the software (if available) and configuration data file from the LSM. 7) The eNB configures additional VLAN/IPs for S1-MME, S1-U/X2. 8) The eNB performs the S1-MME setup with the MME. 9) The eNB performs the X2-C setup with neighbor eNBs if available. 10) The eNB reports the Self-Test result to the LSM. oPOST Result oInventory Information report oeNB status (Cell Operation State) report 11) After receiving the Initialization Complete message, the LSM allows the operator to manage the eNB of the EMS.


How to Activate This section provides the information that you need to configure the feature. Preconditions To fully support Self-establishment feature, DHCP Servers should support vendor specific options. Activation Procedure This feature runs automatically. Deactivation Procedure This feature does not need to be deactivated.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters There are no specific parameters associated with this feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Self-establishment feature operates based on the environment variables as follows:


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DEFAULT_VLANID: Sets VLAN ID for DHCP Process. If this environment variable is not set, eNB will run DHCP process without any vlan tags. Environment Variable Name

Range

Descriptions

DEFAULT_VLANID

1~4094

Sets VLAN ID for DHCP Process. Configuration examples as below: setenv p DEFAULT_VLANID 11

DEFAULT_IPVER: Sets IP version for DHCP process. If this environment variable is not set, eNB will run IPv4 DHCP process. Environment Variable Name

Range

Descriptions

DEFAULT_IPVER

4 6 46 64

Sets IP address version for DHCP process. The meanings of configurable values are: 4: eNB will try IPv4 DHCP process only. 6: eNB will try IPv6 DHCP process only. 46: eNB will try IPv4 DHCP process first and if it fails, eNB will try IPv6 DHCP next. 64: eNB will try IPv6 DHCP process first and if it fails, eNB will try IPv4 DHCP next. Configuration examples as below. setenv p DEFAULT_IPVER 6 setenv p DEFAULT_IPVER 4 setenv p DEFAULT_IPVER 64 setenv p DEFAULT_IPVER 46

BOOTMODE: This environment variable is to set how to configure the IP address for eNB when bootup. Environment Variable Name

Range

Descriptions

BOOTMODE

DHCP STATIC

Sets IP address configuration method for eNB. The meanings of configurable values are: DHCP: eNB will use DHCP protocol to configure the IP/IPv6 address. STATIC: eNB will use the preconfigured values to configure the IP/IPv6 address. Configuration examples as below: setenv p BOOTMODE DHCP setenv p BOOTMODE STATIC

If the BOOTMODE environment variable is configured as STATIC, additional environment variables are needed to be configured. And the additional environment variables are described in the table below. Environment Variable Name

Range

Descriptions

PORT_X_Y_Z_IPVER

4 6

Sets IP address version for preconfigured IP address. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. The meanings of configurable values are:


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Chapter 8 SON Environment Variable Name

Range

Descriptions 4: eNB will use IPv4 address. 6: eNB will use IPv6 address. Configuration examples as below: setenv p PORT_0_0_0_IPVER 6 setenv p PORT_0_0_0_IPVER 4

PORT_X_Y_Z_IPV6_IP

IPv6 address string

Sets IPv6 address for bootup. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV6_IP 3ffe::2

PORT_X_Y_Z_IPV6_NM

0~128

Sets prefix length of IPv6 address. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV6_NM 64

PORT_X_Y_Z_IPV6_GW

IPv6 address string

Sets IPv6 Gateway address. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV6_GW 3ffe::1

PORT_X_Y_Z_IPV4_IP

IPv4 address string

Sets IPv4 address for bootup. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV4_IP 10.1.1.2

PORT_X_Y_Z_IPV4_NM

0~32

Sets prefix length of IPv4 address. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV4_NM 24

PORT_X_Y_Z_IPV4_GW

IPv4 address string

Sets IPv4 Gateway address. ‘X’ means the shelf number, ‘Y’ means the slot number of main card and ‘Z’ means the port number is used for bootup. Configuration examples as below: setenv p PORT_0_0_0_IPV4_GW 10.1.1.1

RS_IP: This environment variable is to set EMS IP address. If the BOOTMODE environment variable is set as DHCP, eNB can receive the EMS IP from DHCP Option 43(IPv4)/Option 17(IPv6). If the BOOTMODE environment variable is set as STATIC, this environment variable should be set mandatorily. Environment Variable Name

Range

Descriptions

RS_IP

IPv4/IPv6 Address string

Sets EMS IP address configuration. Configuration examples as below: setenv p RS_IP 2002::1 setenv p RS_IP 20.1.1.1

FALLBACK_TO_DHCP, ENVUPDATE_ENABLE are supported for Auto Configuration Mode Transition. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 8 SON Environment Variable Name

Range

Descriptions

FALLBACK_TO_DHCP

0, 1

This environment variable can be set for auto transition from STATIC mode to DHCP mode when eNB cannot do loading process successfully. Configuration examples as below: setenv p FALLBACK_TO_DHCP 0 setenv p FALLBACK_TO_DHCP 1

ENVUPDATE_ENABLE

0, 1

This environment variable can be set for auto transition from DHCP mode to STATIC mode when eNB can do loading process successfully when DHCP mode. Configuration examples as below: setenv p ENVUPDATE_ENABLE 0 setenv p ENVUPDATE_ENABLE 1

CLOCK MODE: GPS (Default), GLONASS, Others OTHERS (Optional) Environment Variable Name

Range

Descriptions

eNB ID

VALUE

If configured, eNB will use this value as eNB ID. If not configured, eNB will get eNB ID from EMS. (eNB ID should be pre-provisioned in EMS in this case.)

Counters and KPIs There are no specific counters or Key Performance Indicators (KPIs) associated with this feature

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


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LTE-SO0120, Smart Scheduler IP AutoConfiguration INTRODUCTION Samsung Smart Scheduler IP AutoConfiguration feature supports automatic configuration of eNBs‟ serving Smart Scheduler IP address for the following situations:

Growing of new eNB Growing of new Smart Scheduler Changing capacity of Smart Scheduler In addition, Smart Scheduler IP AutoConfiguration feature supports periodic reconfiguration of Smart Scheduler IP address in order to enable each eNB to be connected to the best serving Smart Scheduler. For the above operations of Smart Scheduler IP AutoConfiguration, basis of selecting serving Smart Scheduler of each eNB is to make adjacent cells (that are in SRS NRT) to be served by the same Smart Scheduler as much as possible. For the purpose, Smart Scheduler IP AutoConfiguration considers the number of eNBs in SRS neighbor relation in determining serving Smart Scheduler of an eNB, which indicates the number of eNBs that owns cells in SRS NRT of the cells in the concerned eNB. Smart Scheduler may perform Smart Scheduling more effectively as the number of eNBs in SRS neighbor relation increases. SRS NRT is a list of neighbor cells from which a cell should monitor sounding reference signal (SRS). The monitored results are used in Smart Scheduling.

BENEFIT Operator can reduce costs required to manually determining serving Smart Scheduler and manually configuring Smart Scheduler IP addresses for eNBs by using this feature.

This feature can contribute to provide better service to user by improving effectiveness of Smart Scheduling.

DEPENDENCY Required Network Elements Smart Scheduler D-RAN Smart

Related Radio Technology eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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E-UTRAN (LTE)

Interface & Protocols D-RAN Smart

LIMITATION Use of LTE-ME6020 SRS SON is recommended for efficient utilization of Smart Scheduler IP optimization function of this feature.

Smart Scheduler IP AutoConfiguration can operate only in the environment of DRAN Smart Network Type.

Information on cell positioning (latitude and longitude information for each cell) is required to enable Smart Scheduler IP Configuration.

Smart Scheduler IP AutoConfiguration feature in a LSM can operate for the eNBs and the Smart Schedulers connected to the same LSM.

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Performance and Capacity This feature may contribute to provide better service to user by improving effectiveness of Smart Scheduling. Interfaces Interface between eNB and LSM is affected for performing Smart Scheduler IP AutoConfiguration feature.

FEATURE DESCRIPTION Architecture Samsung Smart Scheduler IP AutoConfiguration operates in SON Manager of Samsung LSM. Basic structure of Smart Scheduler IP AutoConfiguration is shown in the following figure.


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Overall procedure of Smart Scheduler IP Autoconfiguration is as follows:

1 SON Manager in LSM starts the operation of Smart Scheduler IP AutoConfiguration whenever there is changes in eNB or Smart Scheduler (new installation or capacity change) or at the timing of optimization period.

2 SON Manager in LSM perform the operation of Smart Scheduler IP AutoConfiguration according to the current status of eNBs and Smart Schedulers.

3 SON Manager in LSM applies the newly decided Smart Scheduler IP address to corresponding eNB.

4 Corresponding eNB attaches to the new serving Smart Scheduler based on the configured IP address.

Operation of Smart Scheduler IP AutoConfiguration Smart Scheduler IP Automatic Configuration Procedure for Newly Growing eNB Whenever eNB is newly growing, Smart Scheduler IP AutoConfiguration feature automatically configures serving Smart Schedulers of the growing eNB. Based on location information of the cells in the growing eNB, Smart Scheduler IP AutoConfiguration feature determines the best serving Smart Scheduler for the eNB and configures the corresponding Smart Scheduler IP address. Following figure shows procedure of Smart Scheduler IP AutoConfiguration for the newly growing eNB. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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SON Manager in LSM performs following operations whenever it identifies that an eNB with 'Smart Type' is newly growing:

SON Manager acquires cell position which is configured by operator or Auto GPS.

SON Manager finds the best serving Smart Scheduler of the growing eNB. oFind estimated SRS neighbor relationship table (NRT) of the cells in the growing eNB based on the cell's location information. oForm a list of candidate Smart Schedulers that serve cells in the estimated SRS NRT of the newly growing eNB‟s cells. oIf there exist one or more than one candidate Smart Scheduler: Calculate the number of eNBs in SRS neighbor relation of each candidate Smart Scheduler for the growing eNB. Select a candidate Smart Scheduler with the largest number of eNBs in SRS neighbor relation as serving Smart Scheduler. Smart Scheduler with the largest number of eNBs in SRS neighbor relation means that the Smart Scheduler serves the majority of cells in SRS NRT of the newly growing eNB‟s cells.) oIf there exists no candidate Smart Scheduler: Select a Smart Scheduler having available capacity and serving the same FA as serving Smart Scheduler of the growing eNB. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oIf there exists no available Smart Scheduler: Manage the eNB as 'non allocated eNB'.

SON Manager configures serving Smart Scheduler IP addresses of the growing eNB as that of the selected serving Smart Scheduler, unless there exists no available Smart Scheduler.

If the growing eNB accommodates cells with different FA, above operation is repeated for each FA to configure respective serving Smart Schedulers. Smart Scheduler IP Automatic Configuration Procedure for Newly Growing Smart Scheduler Whenever Smart Scheduler is newly growing, Smart Scheduler IP AutoConfiguration feature automatically allocates existing eNBs (which has no serving Smart Scheduler because capacity of all Smart Schedulers is full) to the new Smart Scheduler. Based on SRS NRT information of the cells in the eNBs without serving Smart Scheduler, Smart Scheduler IP AutoConfiguration feature assigns eNBs without serving Smart Scheduler to the new Smart Scheduler and configures the corresponding Smart Scheduler IP address in the assigned eNBs. Figure below depicts procedure of Smart Scheduler IP Automatic Configuration for the newly growing Smart Scheduler.

SON Manager in LSM performs following operations whenever it identifies that a new Smart Scheduler is newly growing:

SON Manager acquires a list of candidate eNBs with „Smart Type‟ in which serving Smart Scheduler is not configured. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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If there exist no candidate eNB, no eNB is assigned to the new Smart Scheduler. If there exist one or more than one candidate eNB, SON Manager selects eNBs to be served by the newly growing Smart Scheduler among the list of candidate eNBs as follows: oIf the capacity of the new Smart Scheduler is sufficient to accommodate all eNBs in the list of candidate eNBs, all eNBs in the list of candidate eNBs are assigned to the new Smart Scheduler. oIf the capacity of the new Smart Scheduler is not sufficient to accommodate all eNBs in the list of candidate eNBs, SON Manager finds a set of eNBs that does not exceed the capacity limit of the new Smart Scheduler in a manner to maximize the number of eNBs in SRS neighbor relation for those eNBs based on SRS NRT information of the cells in the candidate eNBs.

SON Manager configures serving Smart Scheduler IP address in the selected eNBs to the IP address of the newly growing Smart Scheduler. Smart Scheduler IP Automatic Reconfiguration Procedure for Smart Scheduler Capacity Change If capacity of the Smart Scheduler has increased, selected eNBs without serving Smart Scheduler are assigned to the Smart Scheduler. On the other hand, if capacity of the Smart Scheduler has decreased, serving Smart Schedulers of the eNBs previously connected to the Smart Scheduler changing capacity and the eNBs without serving Smart Scheduler are newly determined. Following figure shows procedure of Smart Scheduler IP Automatic Reconfiguration in case that capacity of Smart Scheduler is changed.


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SON Manager in LSM performs following operations whenever it detects capacity change of Smart Scheduler.

In case that the capacity of Smart Scheduler has increased, SON Manager finds eNBs that will be served by the Smart Scheduler as follows: oSON Manager acquires a list of candidate eNBs with „Smart Type‟ in which serving Smart Scheduler is not configured. oIf there exist no candidate eNB, no eNB is assigned to the Smart Scheduler in which the capacity is increased. oElse if the list of candidate eNBs is not empty, SON Manager selects eNBs to be served by the Smart Scheduler among the list of candidate eNBs as follows: If the increased capacity of the Smart Scheduler is sufficient to accommodate all candidate eNBs, all of the eNBs are assigned to the Smart Scheduler. Else if the increased capacity of the new Smart Scheduler is not sufficient to accommodate all of the candidate eNBs, SON Manager finds a set of eNBs that does not exceed the capacity limit of the new Smart Scheduler in a manner to maximize the number of eNBs in SRS neighbor relation for those eNBs based on SRS NRT information of the cells in the candidate eNBs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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In case that the capacity of Smart Scheduler has decreased, SON Manager finds eNBs that will be served by the Smart Scheduler as follows: oForm a list of candidate eNBs consisting of the eNBs previously connected to the capacity changing Smart Scheduler and the eNBs with „Smart Type‟ currently having no serving Smart Scheduler. oBased on SRS NRT information of the cells in the candidate eNBs, SON Manager finds a set of eNBs that maximizes the SRS neighbor relationship and satisfies the capacity of the Smart Scheduler among the candidate eNBs.

SON Manager configures serving Smart Scheduler IP address in the selected eNBs to the IP address of the corresponding Smart Scheduler. Periodic Scheduler IP Reconfiguration to Maintain Connection with Optimal Serving Smart Scheduler Neighbor relationship can be changed according to the varying wireless network environment. In this case, best serving Smart Scheduler of each eNB also varies. In order to support eNB to maintain connection with the best serving Smart Scheduler, Smart Scheduler IP AutoConfiguration feature supports periodic Smart Scheduler IP Reconfiguration function. Periodic Smart Scheduler IP Reconfiguration is performed by SON Manager in LSM in every predefined period, that is, 1 day.

For each eNB connected to Smart Scheduler, SON Manager determines whether the examining eNB requires Smart Scheduler IP reconfiguration. oIf the examining eNB‟s number of eNBs in SRS neighbor relation of the examining eNB for each of other Smart Scheduler (candidate Smart Scheduler) is larger than that for the current serving Smart Scheduler more than predefined threshold, SON Manager determines that the examining eNB‟s serving Smart Scheduler may be changed to the candidate Smart Scheduler.

If SON Manager determines that Smart Scheduler IP reconfiguration is not required for the examining eNB, serving Smart Scheduler for the examining eNB is not changed.

Else if SON Manager determines that Smart Scheduler IP reconfiguration is required for the examining eNB, SON Manager performs following operation: oIf the capacity of the candidate Smart Scheduler is sufficient to accommodate the cells in the examining eNB, SON Manager decides to change the serving Smart Scheduler of the examining eNB to the candidate Smart Scheduler. oElse if the capacity of the candidate Smart Scheduler is insufficient for accommodating the cells in the examining eNB, SON Manager finds an eNB having the lowest number of eNBs in SRS neighbor relation among those connected to the candidate Smart Scheduler.


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If the number of eNBs in SRS neighbor relation of the found eNB is less than the examining eNB, the new eNB is decided to be connected to the candidate Smart Scheduler. Consequently, new serving Smart Scheduler for the eNB with the lowest number of eNBs in SRS neighbor relation is newly determined as the same procedure above. Else if the number of eNBs in SRS neighbor relation of the found eNB is less than the examining eNB, other Smart Scheduler is considered as new candidate Smart Scheduler and the above procedure is repeated.

SON Manager reconfigures serving Smart Scheduler IP address for the concerning eNBs.


How to Activate This section describes the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure To activate Smart Scheduler IP Automatic Configuration for each eNB, do the following:

Run CHG-SONFN-ENB and set CONFIG_ENABLE to Auto for an eNB. For this configuration, Smart Scheduler IP AutoConfiguration is performed for the eNB. That means, Smart Scheduler IP for the eNB is automatically changed by Smart Scheduler IP AutoConfiguration feature. To activate Smart Scheduler IP Reconfiguration for each eNB, do the following:

Run CHG-SONFN-ENB and set OPTIMIZATION_MODE to Auto for the target eNB. For this configuration, the serving Smart Scheduler IP addresses for the eNB is not automatically changed by the operation of Smart Scheduler IP Optimization and Smart Scheduler IP Reconfiguration due to capacity change of Smart Scheduler. Deactivation Procedure To deactivate Smart Scheduler IP Automatic Configuration for each eNB, do the following:

Run CHG-SONFN-ENB and set CONFIG_ENABLE to Off for the target eNB. Then Smart Scheduler IP AutoConfiguration is not performed for the eNB. That means, Smart Scheduler IP for the eNB is not automatically changed by Smart Scheduler IP AutoConfiguration feature. To deactivate Smart Scheduler IP Reconfiguration for each eNB, do the following:


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Run CHG-SONFN-ENB and set OPTIMIZATION_MODE to Off for the target eNB. For this configuration, the serving Smart Scheduler IP addresses for the eNB is not automatically changed by the operation of Smart Scheduler IP Optimization and Smart Scheduler IP Reconfiguration due to capacity change of Smart Scheduler.

Key Parameters This section describes the key parameters for activation/deactivation of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-ENB/RTRV-SONFN-ENB Parameters

Description

CONFIG_ENABLE

Configures SON Smart Scheduler IP Configuration’s operation mode. Off: Smart Scheduler IP Configuration is not performed. Auto: Scheduler IP Configuration is performed for the corresponding eNB.

OPTIMIZE_MODE

Configures SON Smart Scheduler IP Optimization’s operation mode. Off: Smart Scheduler IP Optimization is not performed. Auto: Scheduler IP Optimization is performed for corresponding eNB.


REFERENCE None


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LTE-SO0201, Intra-LTE ANR INTRODUCTION Samsung automatic neighbor relation (ANR) automatically configures and manages the intra-LTE neighbor relation table (NRT), and it aims to maintain the optimal NRT reflecting changes in the communication environment during the system operation. Stable UE mobility of Samsung LTE cells is guaranteed by optimized NRT management. UE mobility is guaranteed as follows according to UE connection status.

RRC_CONNECTED: Guarantees stable intra-LTE HO of the UE while connected to the cell.

RRC_IDLE: Guarantees stable execution of cell selection/reselection of the UE while the cell is disconnected. Samsung ANR provides the following functions depending on the SON phase:

Self-configuration phase oInitial NRT auto-configuration through O&M: Create an initial NRT by using the location information of active cells during the eNB or cell growing procedure.

Self-optimization phase oFinds and adds new neighbor cells during HO execution due to UE mobility. iAdds new neighbor cells to the NRT based on the UE or LSM. iiEstablishes bi-directional NR relations by adding the serving cell to the NRT of a new neighbor cell with the help of the LSM. iiiSets the automatic X2 interface between the serving cell and the new neighbor cell. oFinds and adds neighbor cells based on ANR specific event iPerforms ANR measurement by configuring ANR specific event with the UE selected among the ones which initially attach or perform handover to this cell. iiIf the best neighbor cell included in the measurement report (MR) message triggered by ANR specific event is unknown, adds this cell to NRT based on the UE or LSM. iiiEstablishes bi-directional NR relations by adding the serving cell to the NRT of a new neighbor cell with the help of the LSM. ivConfigures the X2 interface automatically between a serving cell and new neighbor cell. oAdds neighbor cells based on RLF INDICATION message


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If the cell which sent RLF INDICATION message does not exist in NRT, eNB adds the cell in NRT. oANR control function per carrier/operator iPrevents adding a new neighbor cell of a specific carrier to NRT by controlling the ANR measurement by carrier. iiPrevents the X2 interface from being configured with the neighbor eNB, which belongs to a specific operator by controlling X2 configuration by operator. iiiPrevents adding a new neighbor cell, which belongs to a specific operator by controlling neighbor cell addition function per operator. oAutomatic NRT management function iNR ranking calculation: The NR ranking is calculated using the number of MR messages received for HO. iiNRT size management: The number of NRs in the NRT should be managed so that it does not exceed the pre-defined maximum size. Guarantees the minimal number of effective neighbor cells per carrier if attempting to add a new NR when the NRT is full. iiiUnnecessary NR removal: When the number of MR messages received for an NR is reduced due to UE not reporting them any longer, this function removes the NR based on the specific threshold, which enables for the NRT to include only valid NRs. ivManagement of NR causing HO performance degradation: If the number of HO success for an NR is extremely low in spite of considerable number of HO attempts, this function removes the NR or manages it as HO blacklist based on the two respective thresholds for HO success and attempts. vInvalid NR management: If the number of successive HO failure for an NR is larger than a threshold, this function removes the NR or manages it as HO blacklist. viHO blacklist management: This function manages the NRs causing HO performance degradation or invalid NRs as HO blacklist. oAutomatic X2-NRT management function iX2 NR ranking calculation: X2 NR ranking is calculated using the number of HO attempts. iiX2-NRT size management: The number of X2 NRs in X2-NRT should be managed so that it does not exceed the pre-defined maximum size. eNB considers the number X2 NRs to be guaranteed per band indicator iiiUnnecessary X2 NR blacklisting: If ratio of handover attempt to an X2 NR is lower than predefined threshold, this function disconnects X2 link with the unnecessary X2 NR.


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ivX2 link restoring: If ratio of S1 handover attempt to an X2 NR is larger than predefined threshold, this function restores the X2 link with the X2 NR. oConfigures the neighbor cell lists used in measurement configurations Configures the best neighbor cell list, which includes a maximum of 32 cells for each carriers‟ measurement configuration in the order of descending ranking, for the purpose of joint optimization with the Samsung MRO function.

BENEFIT The operator can reduce CAPEX and OPEX costs for configuring and managing the NRT of the LTE cells.

The system performance indicators such as HO success rate and call drop rate are optimized by configuring an NRT optimized for coverage and air status of each LTE cell. This guarantees reliable mobility of the UEs in the RRC_IDLE mode and the RRC_CONNECTED mode.

DEPENDENCY Prerequisite Features LTE-SW5012 (Operator Specific Feature Activation)

Others For UE-based NR addition, the UE should support the E-UTRAN cell global identifier (ECGI) acquiring function.

LIMITATION Bi-directional NR addition is possible only when the new neighbor cell belongs to the same LSM as the serving cell. Bi-directional NR relations cannot be established with the neighbor cells that are located in a different LSM or that belong to a different vendor.

To use Initial NRT auto-configuration and NRT re-initialization function, location information of the cell should be configured

SYSTEM IMPACT Interdependencies between Features X2 Interface Management: X2 Interface Management feature manages the signaling associations between eNBs, surveying X2 interface and recovering from errors.

PCI Auto-configuration: PCI Auto-configuration feature automatically detects PCI conflict between cells and reallocates a new PCI to the cell involved in PCI conflict. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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RACH Optimization: RACH Optimization feature automatically detects RSI collision between cells and reallocates a new RSI to the cell involved in RSI collision. Performance and Capacity Intra-LTE ANR automatically configures NRT optimized for coverage and air status of LTE cell. This guarantees reliable mobility of the UEs in the RRC_IDLE mode and the RRC_CONNECTED mode. Interfaces Intra-LTE ANR automatically sets up X2 interface with neighbor eNBs and neighbor information added by Intra-LTE ANR is included in X2 Setup Request/Response and eNB Configuration Update messages.

FEATURE DESCRIPTION Architecture The Samsung ANR function operates in the eNB and LSM. The overall architecture is shown in the following figure:

As shown in figure above, the Samsung ANR function is executed at the eNB SON Agent and at the LSM SON Manager. The operation of each entity in this architecture is described below. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1 LSM SON Manager: NRT Management Function oCreates initial NRT oPerforms LSM-based NR addition oEstablishes bi-directional NR relationship based on the LSM

2 eNB SON Agent: NR Detection Function oReceives the measurement report message for HO from the call processor oReceives the measurement report message for periodic ANR from the call processor oAcquires the ECGI and the X2 TNL address from the Call Processor

SON Agent: NR Add Function oAdds a neighbor cell by using the ECGI information oAdds a neighbor eNB by using the X2 TNL address information. If the configuration of the X2 interface with a specific operator is not allowed, configure as NoX2 = True.

SON Agent: NR Removal Function oDeletes the NR by receiving the information on the deletion of the NR from the Call Processor (Served Cells to Delete IE in the X2 ENB CONFIGURATION message). oRemoves unnecessary NR. oManagement of the NR that causes HO performance degradation. oManagement of the invalid NR.

SON Agent: NR Ranking Function oCalculates the ranking of NR by using the number of received MR messages. oSends the NR ranking information to the Call Processor in order to create the neighbor cell list for measurement configuration.

SON Agent: NRT Management Function oDecides whether to perform NR addition/retrieval/attribute value update/deletion. oLSM SON Manager: Synchronizes the NRT management function with the NRT. oManages the NRT size so that it does not exceed the specified threshold (maxNRTSize). Guarantees the minimal number of effective neighbor cells per carrier if attempting to add a new NR when the NRT is full.


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Intra-LTE ANR Function Self-Configuration Phase-Initial NRT Auto-configuration Samsung LSM provides the eNB or cell grow window with a SON option box. If the Initial NRT Generation option in the box is checked, an initial NRT is generated using the cells‟ location information. This information is entered in the LSM after the software download to the cell has completed. The Samsung LSM SON property window includes the following parameters, which are used to generate the initial NRT.

1 NRT.type: Decides the initial NRT creation method 2 NRT.multiple: A multiple for multiplying R counts (used in initial NRT creation) and an average distance to the cells

3 NRT.limitDistance: The maximum distance to the neighbor cell that can be included in the initial NRT Samsung LSM provides the following Initial NRT generation methods.

4 NRT.type = average Creation method: Includes neighbor cells in the NRT within the radius of max{NRT Multiple × Ravg, NRT.limitDistance} up to NRT.size per carrier registered in EUTRA-FA. oRavg: The average distance of R Count of cells within the NRT.limitDistance. R Count: The number of cells to be used for the Ravg calculation oNRT.size: The number of the initial NRT configurations

5 NRT.type = distance Creation method: Includes neighbor cells in NRT within the radius of NRT.limitDistance up to NRT.size per carrier registered in EUTRA-FA.

6 NRT Type = minimum Creation method: Creates an initial NRT in the same way as NRT.type = average, but the distance to the closest cell among the cells remaining within NRT.limitDistance is used instead of Ravg. Self-Optimization Phase-Automatic NRT Management In the Self-optimization phase, the Samsung ANR function provides the following features: Finds and Adds New Neighbor Cells during HO Execution due to UE Mobility Samsung NR addition function is triggered by an event where new neighbor cells are found during the HO execution due to the UE mobility. In order to add the cell to the NRT, if an ECGI can be acquired from the UE, the UE-based NR addition is executed; if an ECGI cannot be acquired, the LSM-based NR addition is performed. The ECGI can be acquired from the UE when the UE supports ECGI acquiring function as a UE feature and the serving cell uses discontinuous reception (DRX). The UE-based NR addition procedure uses the following steps: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1 The UE performs measurements according to the measurement configuration transmitted by the serving cell.

2 The UE transmits the measurement report (MR) message to the serving cell. 3 In case that, the serving cell detects the PCI (Unknown PCI) of the new cell that does not exist in its own NRT, the serving cell checks if condition 1 or condition 2 is satisfied. oCondition 1: the UE which sent the MR message does not use GBR service. oCondition 2: the UE which sent the MR message uses GBR service but the value of GBR_REPORT_CGI_OPTION (Command: CHG-SON-ANR) is set as HoEventAnr or BothAnr.

4 If the condition in step 3 is satisfied, the serving cell transmits the reportCGI configuration requesting the UE to acquire the ECGI. oIf the ANR measurement for the carrier of a new cell is not allowed, the neighbor cell is not added (that is, the procedure is terminated). Setting parameter: ANR_ALLOW (Command: CHG-EUTRA-FA) ANR_ALLOW: If the parameter is set to no use,‟ the ANR measurement is not allowed. oCommands for DRX operation setting: CHG-DRX-INFO QCI: QCI index (1~9) used in UE-based NR adding function DRX_CONFIG_SETUP: ci_Config_reportCGI ON_DURATION_TIMER_REPORT_CGI: ci_onDurationTimer_psf10 DRX_INACTIVITY_TIMER_ REPORT_CGI: ci_drx_InactivityTimer_psf10 DRX_RETRANSMISSION_TIMER_ REPORT_CGI: ci_drx_RetransmissionTimer_sf16 LONG_DRXCYCLE_START_OFFSET_TYPE_REPORT_CGI: ci_sf2560_chosen oTo handle the exception case of DRX operation, SON Agent runs the EUTRA_REPORT_CGI_MR_TO_WAIT timer. If UE cannot acquire the ECGI/CGI within the time, SON Agent terminates the DRX operation to return the normal state of service.

5 The UE reads the ECGI of the new cell corresponding to the Unknown PCI in the DRX period.

6 The UE transmits the measurement report message including the acquired ECGI to the serving cell.

7 The serving eNB checks whether PLMN ID in MR message is registered in SonAnrPlmnBlackListInfo PLD. oIn case that the PLMN ID is registered in SonAnrPlmnBlackListInfo PLD and its USED_FLAG = use, If EUTRA_BLOCK_FLAG = True, serving eNB terminates ANR operation. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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If EUTRA_BLOCK_FLAG = False, serving eNB performs step 8. oIn case that the PLMN ID is not registered in SonAnrPlmnBlackListInfo PLD or the PLMN ID is registered and its usedFlag = no_use, Serving eNB performs step 8.

8 The serving eNB acquires the IP address (X2 TNL address) of the new eNB from the MME.

9 The serving cell adds the new cell to its NRT. 10 The serving eNB reports to the LSM that the new cell added to its NRT. 11 The LSM adds the serving cell to the new cell's NRT (Bi-directional NR adding).

12 The serving eNB and new eNB determine whether to establish X2 connection as follows. oIf the configuration of the X2 interface for the PLMN of the new eNB is allowed, serving eNB sends X2 Setup Request to the new eNB. oIf the configuration of the X2 interface for the PLMN of the new eNB is not allowed, set NoX2 = True for the neighbor eNB X2 interface configuring command by PLMN: CHG-PLMNANR-ENB ANR_TARGET_MCC: MCC of Neighbor eNB ANR_TARGET_MNC: MNC of Neighbor eNB USE_NBR_NO_X2: In case of use, set NO_X2 = True for the neighbor eNB with the PLMN. The following figure illustrates the UE-based NR addition procedure:


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The LSM-based NR addition procedure uses the following steps:

1 The UE performs measurements based on the measurement configuration sent by the serving cell.

2 The UE transmits the measurement report message to the serving cell. 3 After the serving cell detects a PCI of a new cell which does not exist in its NRT (Unknown PCI), it reports to the LSM that unknown PCI is detected, since acquiring ECGI from the UE is not available. oIf the ANR measurement for the carrier of a new cell is not allowed, the neighbor cell is not added (the unknown PCI detection is not reported to LSM).

4 The LSM finds the nearest cell which corresponds to the serving eNB and unknown PCI, and adds new cell to the serving cell‟s NRT without consideration of the new cell's PLMN.

5 The LSM adds the serving cell to the new cell‟s NRT (bi-directional NR adding). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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6 The serving eNB and new eNB set the X2 connection. oIf configuration of the X2 interface for PLMN of the new eNB is not allowed, set NoX2 = True for the neighbor eNB. The following figure illustrates the LSM-based NR addition procedure:

Finds and Adds New Neighbor Cells Based on the ANR specific-event and Renewal of NR Info. If a large volume of new cells are deployed to the network rapidly, the neighbor cells should be included in the NRT. As a result, reliable UE mobility can be supported. In this scenario, the Samsung ANR performs the additional NR adding function that periodically finds and adds new neighbor cells. With this function, the optimum NRT achievement rate is improved and reliable network operation is available sooner. In addition, to stabilize the network, Samsung ANR checks whether or not NR information which is already included in NRT is updated. The cycle of the function is set by date/hour/minute/performing duration and through this cyclical operation and the activation/deactivation flag, the operator can control overheads which occur at the eNB and UE.


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The LTE cell decides which UEs will perform the function among the ones who initially attach or enter the cell due to a handover according to the UE search rate set by each cell (ANR_UE_SEARCH_RATE_TOTAL). Then, the LTE cell decides which the selected UE measures among the LTE intra-frequency (ANR_UE_SEARCH_RATE_INTRA_FREQ), the LTE inter-frequency (ANR_UE_SEARCH_RATE_INTER_FREQ), and the UTRAN carriers (ANR_UE_SEARCH_RATE_UTRAN). For example, if the LTE network has two carriers and the UTRAN network has a few carriers, assume that the UE search rates are configured as ANR_UE_SEARCH_RATE_TOTAL = 5 %, ANR_UE_SEARCH_RATE_INTRA_FREQ = 40 %, ANR_UE_SEARCH_RATE_INTER_FREQ = 40 %, and ANR_UE_SEARCH_RATE_UTRAN = 20 %. Then, 2 % of UEs for the LTE intra-frequency, 2 % of UEs for the LTE inter-frequency, and 1 % of UEs for the UTRAN carriers will perform measurement for this function. The Samsung periodic ANR operation procedure uses the following steps:

1 To start the function, the LTE cell selects the target UE among the ones which initially attach or perform handover and the target carrier, and then sends the RRC Connection Reconfiguration message to the target UE including the ANR measurement configuration with target carrier to the target UE. oThe function checks whether the UE supports intra/inter-frequency ANR operation based on the FeatureGroupIndicators IE included in the UEEUTRA-Capability IE Intra-frequency ANR support: 17th bit = 1 Inter-frequency ANR support: 18th bit = 1 & 25th bit = 1 oTarget UE selection Generates three random number (N1,N2,N3) ranging from 0 to 1 If N1 < ANR_UE_SEARCH_RATE_TOTAL, the LTE cell selects the UE oTarget carrier selection According to the UE Capability, the method to select the target carrier for ANR is as follows: If the UE supports the LTE intra/inter-frequency ANR and the UTRAN ANR operation, sets the intervals for the LTE intrafrequency (ANR_UE_SEARCH_RATE_INTRA_FREQ: y1), the LTE inter-frequency (ANR_UE_SEARCH_RATE_INTER_FREQ:y2), and the UTRAN carriers (ANR_UE_SEARCH_RATE_UTRAN:y3). In this case, the intervals are separated into 3 parts: If the UE supports only the LTE intra/inter-frequency ANR operation, sets the intervals for the LTE intra-frequency (ANR_UE_SEARCH_RATE_INTRA_FREQ: y1), the LTE interfrequency (ANR_UE_SEARCH_RATE_INTER_FREQ:y2). In this case, the intervals are separated into 2 parts: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Selects one among intra-frequency ANR, inter-frequency ANR, and UTRAN ANR according to the random value N2. When the LTE intra-frequency ANR is selected, the UE performs periodical measurement for intra-frequency. When the LTE inter-frequency ANR is selected and there are more than 1 inter-carrier, sets the interval for each UE-supportable inter-carrier with the ANR_UE_SEARCH_RATE in the ascending order of the carrier index x_{k}: ANR_UE_SEARCH_RATE set to k^{th} inter-carrier index the interval for k^{th} carrier a) Minimum value in the interval: is 0)

(if k = 0, the value

b) Maximum value in the interval: After selecting one among UE-supportable LTE inter-carriers according to the random value N3, the UE performs periodical measurement for the target inter-frequency. oANR measurement configuration setting If the selected carrier is intra-frequency  ReportConfigEUTRA: configures ANR specific A3 event If the selected carrier is inter-frequency If A2 event is used for inter-frequency ANR - ReportConfigEUTRA: configures ANR specific A2 event If A2 event is not used for inter-frequency ANR or the eNB receives MR message due to ANR specific A2 event - MeasObjectEUTRA: Sets the target carrier - ReportConfigEUTRA: configures ANR specific A4 event - Configures measurementGap

1 The UE transmits measurement report message to serving cell corresponding to the ANR measurement configuration.

2 In case that, the serving cell perceives that the PCI of the best neighbor cell in the message is a new cell which is not in its NRT, the serving cell checks if condition 1 or condition 2 is satisfied. oCondition 1: the UE which sent the MR message does not use GBR service. oCondition 2: the UE which sent the MR message uses GBR service but the value of GBR_REPORT_CGI_OPTION (Command: CHG-SON-ANR) is set as HoEventAnr or BothAnr.

3 If the condition in step 3 is satisfied, the serving cell performs the UE-based NR addition. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oIf the ANR measurement for the carrier of a new cell is not allowed, the neighbor cell is not added (The detail on the unknown PCI detection is not reported to LSM) oPlease refer to the 4~12 of Section Finds and Adds New Neighbor Cells during HO Execution due to UE Mobility for the detail operation of the next procedure.

4 The serving cell runs NR information update procedure based on Validity Check Flag, if PCI of best neighbor cell existed in NRT is reported. oIf the value of Validity Check Flag is True, nothing occurs. oIf the value of Validity Check Flag is False, serving cell sends RRCConnectionReconfiguration message to UE for ECGI/PCI acquisition. Then, the serving cell updates NRT, if it is necessary. If the ECGI acquired by the UE exists in the NRT: Maintains NR information if the PCI of the NR is same with the PCI acquired by the UE. Changes the PCI of the NR as the PCI acquired by the UE if the PCI of the NR is different from the PCI acquired by the UE. If the ECGI acquired by the UE does not exist in the NRT: Adds the new NR in the NRT by using the information acquired by the UE. The UE-based NR addition following the scheduled NR adding function is shown below:


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Adds new neighbor cells based on RLF INDICATION message In case that served cell (Cell A) of Samsung eNB (eNB 1) receives RRC Connection Reestablishment Request message from a UE, eNB 1 checks if it has the context of the UE which sent RRC Connection Reestablishment Request message. If eNB 1 does not have the UE Context, it transmits RLF INDICATION message to the all cells which have the same PCI as the PCI in RRC Connection Reestablishment Request message. Served cell (Cell B) of eNB 2 which receives RLF INDICATION message from eNB 1 checks if Re-establishment cell ECGI (Cell A) in RLF INDICATION message is included in its own NRT. If Cell A is not included in Cell B‟s NRT, Cell B adds Cell A in its NRT. The procedure of NR addition based on RLF INDICATION is shown below.


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Automatic NRT management function Samsung periodic NRT management procedure uses the following steps:

1 The serving cell collects the statistics number of MR messages received for the HO to neighbor cells included in the NRT.

2 When calculate the NR ranking arrives, the serving cell calculates ranking of the NRs included in the NRT based on the collected statistics.

3 The serving cell considers the NR with a low number of MR messages for HO as unnecessary and removes it from the NRT.

4 The serving cell considers the NR with an extremely low HO success rate as a HO performance degradation causing NR and then, the serving cell removes it from the NRT or manages it as HO blacklist. In addition, if a NR satisfies the predefined condition by analyzing HO preparation failure cause, Samsung ANR removes the invalid NR from the NRT or manages it as HO blacklist.


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1) NR Ranking Calculation The NR ranking reflects the validity or importance of an NR included in the NRT. The Samsung eNB defines the NR ranking‟s attribute as having the higher ranking when more MR messages are received as the HO for the NR is triggered. The NR ranking is performed as follows:

1 The NR ranking calculation is performed at a specified interval. 2 The NR related to ranking calculation must be included in the NRT at least beyond the ranking calculation interval.

3 The ranking value used between the ranking calculation intervals uses the ranking value calculated in the previous interval. The following figure illustrates the NR ranking operation with an example:


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The NR ranking is calculated based on statistics. To compare the rankings of NRs, the period for collecting the statistics should be the same among the NRs. In the previous figure, New NR (NR j) is added at 16:00, the statistics for NR is collected only for 11 hours. On the other hand, the statistics for the NR previously added (NR i) is collected for 24 hours. Since the comparison of the ranking between NR i and NR j is imbalanced, we distinguish the ranking calculation method for these two NRs. The NR Ranking is calculated as follows:

1 The currentRank value for the NR i which is in the NRT for more than one NR ranking calculation period as follows:

ok: current ranking calculation time oω: IIR filter coefficient that gives some weights to the previous rank value and the current statistics o o

: The rank value calculated in the last period : The number of MR message received for the Cell i, which is collected from the previous ranking calculation point k-1 to point k

o

: The number of TooLateHoRlfBeforeTriggering statistics for Cell i

o

: The number of reportCGI requests for Cell j

oJ: The set of the neighbor cells which have the same PCI and EARFCN with Cell i except for Cell i

2 The currentRank value for the NR j which is in the NRT for less than a NR ranking calculation period as follows: oFrom the NR ranking calculation point k, eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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currentRank_{j}(k) = -1 Maintain the value at-1 until the NR Ranking calculation period. oAt the next ranking calculation point k + 1, currentRank_{j}(k + 1) = NMR_{j}(k + 1) If the number of MR messages received for NR j is 0, NMR_{j}(k + 1) is set to 0. At k + 2 (next ranking calculation time after k + 1), the rank value of NR j is calculated as the same way as NR i which is explained above. 2) NRT Size Management The MAX_NRT_SIZE presents maximum number of NRs that can be included in the Intra-LTE NRT. NRT size management is performed as follows:

1 MAX_NRT_SIZE: Unless a service provider requests for a separate value, default value is set as 256. (Command: CHG-SON-ANR)

2 Intra-LTE NRT is managed so that no more NRs than the MAX_NRT_SIZE could be included. When the attempt of adding a new NR occurs, in the situation where the existing number of NRs is as many as MAX_NRT_SIZE in Intra-LTE NRT, the following operations are performed depending on the ANR setting mode.

3 ANR_ENABLE = Auto or Manual oReason for new NR addition attempt NR addition by UE-based ANR function NR addition by LSM-based ANR function NR addition by LSM-based bi-directional addition function Manual addition by the operator oOperation procedure iIn case of carriers which NRs in NRT are larger than MIN_NRT_SIZE_CARRIER (i), Parameter for setting the minimal number of effective neighbors by carrier: MIN_NRT_SIZE_CARRIER (Command: CHG-EUTRAFA) - If the MAX_NRT_SIZE change attempting value is larger than the value adding the sum of MIN_NRT_SIZE_CARRIER (i) for all carriers and the number of NR belonging to the HO blacklist, it changes. iiAmong the NRs with CurrentRank ≠ -1, The NR whose CurrentRank = -1 is excluded from the list of removal since it existed less than the NR ranking interval in NRT. iiiThe lowest ranking NR with the remove attribute (T) is deleted and a new NR is added. ivIn case of Manual addition by the operator: the New NR is not added. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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4 ANR_ENABLE = Off oReason for new NR addition attempt NR addition by LSM-based bi-directional addition function Manual addition by the operator oOperation procedure In case of NR addition by LSM-based bi-directional addition function: Same as the operating procedure (1) In case of Manual addition by the operator: the New NR is not added The following figure shows the ranking based NR removal function used to manage the NRT size:

3) Unnecessary NR Removal When the network is stabilized through the network optimization, this function removes NRs which cannot receive MR messages among the NRs included when the network was initially created, so that only valid NRs could be included in the NRT. The operator can control this function‟s ON/OFF state, and at the NR ranking calculation point k, the serving cell removes the NR i which meets the following conditions.

1 ANR_ENABLE = Auto or Manual & 2 NR_DEL_FLAG = True & oNR_DEL_FLAG: ON/OFF control flag that determines the operational status.

3 ANR_ALLOW = True for the carrier in which NR i is operating 4 CumulatedMRi (k) ≤ TH_NUM_MR_NR_DEL & oCumulatedMRi(k): The number of MR messages received for NR i during TH_TIME_NR_DEL period at the NR ranking calculation point k. oTH_NUM_MR_NR_DEL: The threshold value to decide unnecessary NR. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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5 IS_REMOVE_ALLOWED = True for NR i The following figure shows the statistics based NR removal function used to delete unnecessary NRs:

4) Management of NR causing HO performance degradation If a new cell located nearby has the same PCI as the PCI of a distant NR, which is included in the NRT at the initial network formation and UE transmits a measurement report message for HO while moving to the new cell. Due to this, the serving cell wrongly recognizes the PCI in the message as belonging to the distant NR. Therefore, UE fails the HO execution. The following figure illustrates the management scenario of the NR causing HO performance degradation:

In the previous figure, UE moves toward the neighbor cell (ECGI = 1002) and transmits the measurement report message including PCI = 20 by HO triggering to the serving cell (ECGI = 1000). The serving cell completes HO preparation using the NR (ECGI = 1001) included in the NRT, and then transmits the HO command message received from the NR. However, UE is moved to the new cell (ECGI = 1002), thus HO execution fails. As shown the figure above, Samsung ANR removes the HO performance degradation causing NR from the NRT or manages eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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it as HO blacklist. The operator can control this function‟s ON/OFF state, and at the NR ranking calculation point k, the serving cell removes the NR i from the NRT or manages it as HO blacklist which meets the following conditions.

1 ANR_ENABLE = Auto or Manual & 2 WRONG_NR_DEL_FLAG = True & oWRONG_NR_DEL_FLAG: ON/OFF control flag that determines the operational status.

3 ANR_ALLOW = True for the carrier in which NR i is operating 4

& o

: The number of HO preparation successes collected for NR i during TH_TIME_NR_DEL at the NR ranking calculation point k.

oTH_HO_PREP_SUCC_NR_DEL: The threshold value of HO attempts to decide HO performance degradation causing NR.

5

& o

: The number of HO success collected for NR i during TH_TIME_NR_DEL period at the NR ranking calculation point k.

oTH_HO_SUC_RATE_NR_DEL: The threshold value of the HO success rate to decide HO performance degradation causing NR.

6 IS_REMOVE_ALLOWED = True for NR i 5) Management of invalid NR

Determination of invalid NR which causes HO preparation failure a. Serving cell removes the invalid NR from the NRT or manages it as HO blacklist if the number of successive HO preparation failures is larger than the predefined threshold. The threshold can be configured by operator for each HO preparation failure cause. oIn order to use this function, following parameter configuration is required. ANR_ENABLE = Auto or Manual NBR_DEL_CAUSE_FLAG = True Threshold > 0 per Cause The following table shows S1 HO preparation failure causes. Causes

Meaning

Handover Failure In Target EPC/eNB Or Target System

The handover failed due to a failure in target EPC/eNB or target system.

TS1RELOCprep Expiry

Handover Preparation procedure is cancelled when timer TS1RELOCprep expires.

Cell not available

The concerned cell is not available.

Unknown Target ID

Handover rejected because the target ID is not known to the EPC.

Unknown PLMN

The MME does not identify any PLMN provided by the eNB.


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The following table shows X2 HO preparation failure causes Causes

Meaning

TRELOCprep Expiry

Handover Preparation procedure is cancelled when timer TRELOCprep expires.

Cell not available

The concerned cell is not available.

6) HO blacklist management

1 NR can be managed as HO blacklist if the NR is determined as the invalid NR or the NR causing HO performance degradation in case of BLACK_LIST_MGMT_FLAG = True. oIn case of BLACK_LIST_MGMT_FLAG = False, eNB removes the invalid NR or the NR causing HO performance degradation from the NRT.

2 Serving cell performs validation check for the NR managed as HO blacklist by acquiring ECGI of the NR through reportCGI once during ranking period.

3 NRs can be changed from HO blacklist to the HO whitelist for the following cases oECGI information of the NR is changed by reportCGI operation. oThe value of hand-in statistics for the HO blacklist NR is larger than TH_HAND_IN_4_BLACK_2_WHITE. oOperator changes the HO attribute of the NR from HO blacklist to HO whitelist. Automatic X2-NRT Management Function 1) X2 NR Priority (ranking) Calculation The X2 NR ranking (priority) means the validity or significance of the X2 NR included in X2 NRT. Samsung Intra-LTE ANR function defines that the X2 NR ranking attribution has higher ranking as the more number of S1/X2 HO triggering for X2 NR increases. X2 NR ranking is operated in the method shown below:

1 The X2 NR ranking calculation is performed after cell NR ranking. 2 The X2 ranking value used between the ranking calculation intervals uses the ranking value calculated in the previous interval. X2 NR ranking uses S1/X2 HO statistics and is calculated as shown below:

3 Collecting HOIn (i) statistics for X2 NR i in X2 NRT oReceive HANDOVER REQUEST (S1/X2). oIndex eNB i corresponding to the top ECGI in Last Visited Cell Information IE included in UE History Information IE. oIncrease HOInS1 (i) or HOInX2 (i) by HO triggering type. oHOIn (i) = HOInS1 (i) + HOInX2 (i)

4 Collecting HOOut (i) statistics for X2 NR i in X2 NRT oTransmit HANDOVER REQUIRED (S1) or HANDOVER REQUEST (X2). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oIncrease HOOutS1 (i) or HOOutX2 (i) for eNB i as target of HO. oHOOut (i) = HOOutS1 (i) + HOOutX2 (i)

5 Calculating the currentX2Rank value by X2 NR as follows: currentX 2Ranki (k )  (1  )  previousX 2Ranki (k )    tempCurrentX 2Ranki (k )

k: X2 NR ranking calculation time ω: IIR filtering coefficient previousX2Ranki (k): X2 rank value calculated in the previous interval  I: Total number of X2 NRs in X2 NRT HOOut (i): S1/X2 HO-Out attempt count to neighbor eNB i at this interval HOIn (i): S1/X2 HO-In attempt count collected to neighbor eNB i at this interval

6 Setting the currentX2Rank value for the new X2 NR j which existed within the NR ranking calculation period in X2 NRT DEFAULT_VALUE_X2: configurable system parameter 2) X2-NRT Size Management The MAX_X2_NRT_SIZE means the maximum number of X2 NRs, which can be included in the Intra-LTE X2 NRT, and is operated as the following:

1 MAX_X2_NRT_SIZE: Different initial value can be set per service provider. 2 The eNB does not include X2 NRs more than X2 NRT hard limit in Intra-LTE X2-NRT. Also, it manages the number of X2 NRs included in the Intra-LTE X2-NRT not to exceed the MAX_X2_NRT_SIZE every ranking period.

3 If the operator configures the X2GuaranteedBandInfo to maintain minimum number of X2 Links for a specific band indicator, the eNB performs X2 NR deletion function for X2-NRT size management by considering the value of the parameters in X2GuaranteedBandInfo. When an attempt occurs to add a new X2 NR, in the situation where there exist X2 NRs as many as MAX_X2_NRT_SIZE in Intra-LTE X2 NRT, eNB allows X2 NR addition until X2-NRT hard limit size. If there is a request for adding a new X2 NR when there exist X2 NRs as many as X2-NRT hard limit, eNB deletes a X2 NR with the lowest CURRENT_X2_RANK among the X2 NRs with NO_REMOVE = False and NO_X2 = True. If there is no X2 NR with NO_X2 = True, eNB does not add the new X2 NR. The eNB manages the number of X2 NRs included in the Intra-LTE X2-NRT not to exceed the MAX_X2_NRT_SIZE every ranking period through following operation.

1 Include in X2-NRT in order of X2 ranking among X2 NRs as NO_REMOVE = True. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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2 In the order of index of band indicator in X2GuaranteedBandInfo, includes the X2 NRs which supports the band indicator in the X2-NRT from the order of higher X2 ranking until the number of X2 NR reaches MIN_X2_NRT_SIZE. oIf the number of X2 NRs in X2-NRT is larger or equal to MAX_X2_NRT_SIZE at step (2), omit step (3). oThrough the steps (1) and (2), the number of X2 NRs can be larger than MAX_X2_NRT_SIZE.

3 Includes X2 NR in the X2-NRT from the order of higher X2 ranking until the number of X2 NR reaches MAX_X2_NRT_SIZE. X2-NRT Size Management operation is shown in the following figure:

3) Unnecessary X2 NR blacklisting In order to reduce X2 signaling load caused by invalid X2 NR, if ratio of handover attempt to an X2 NR is lower than predefined threshold, this function disconnects the X2 link with the unnecessary X2 NR. The operator can control this function‟s ON/OFF state by configuring NR_X2_BLACK_ENABLE. At the X2 NR ranking calculation point k, the serving eNB disconnects X2 Link by changing the attribute of noX2 of X2 NR i which meets the following conditions from False to True.

1 SON_X2_MGMT_ENABLE = Auto & 2 NR_X2_BLACK_ENABLE = Auto & 3

& o

: The average occurrence ratio of handover to X2 NR i during thTimeNrDel at the X2 NR ranking calculation point k

oWEIGHT_TH_X2_BLACK: weight factor for determining the threshold for judging the X2 NR as an invalid X2 NR eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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o

: the number of X2 NRs which exist in X2-NRT more than TH_TIME_NR_DEL

4 NO_REMOVE = False for X2 NR i The following figure shows the statistics based X2 NR removal function.

4) X2 Link restoring eNB restores the X2 Link of the X2 NR by changing the attribute of noX2 from True to False if the currentX2Rank is larger than the predefined threshold at X2 NR ranking calculation point. The operator can control this function‟s ON/OFF state by configuring NR_X2_RE_ENABLE. At the X2 NR ranking calculation point k, the serving eNB restores X2 Link by changing the attribute of noX2 of X2 NR i which meets the following conditions from True to False.

1 SON_X2_MGMT_ENABLE = Auto & 2 NR_X2_RE_ENABLE = Auto & 3

& oWEIGHT_TH_X2_RE: weight factor for determining the threshold for judging the X2 NR as an X2 NR to be restored o

: the number of X2 NRs which exist in X2-NRT more than ranking calculation period (rankPeriod)

4 NO_REMOVE = False for X2 NR i Creates Neighbor Cell Lists for Measurement Configuration The LTE cell can transmit to UE the measurement configurations of a maximum of 32 frequencies and information of a maximum of 32 neighbor cells for each configuration (cell individual offset). Cell individual offset is a parameter which optimizes and improves each NR‟s HO performance in the Samsung MRO function. For the purpose of joint optimization with Samsung MRO function, Samsung ANR function configures a maximum of 32 neighbor cell lists for each frequency‟s measurement configuration in the order of ranking. HO performance can be improved, when the cell individual offset value optimized for each neighbor cell is transmitted to UE in the order of the nearest coverage with the serving cell. The procedure for this operation is as follows. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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1 NRs with IS_HO_ALLOWED = True & IS_REMOVE_ALLOWED = False are configured in the neighbor cell list in the order of ranking.

2 (If it is not filled) NRs with IS_HO_ALLOWED = True & IS_REMOVE_ALLOWED = True are configured in the neighbor cell list in the order of ranking.


How to Activate Preconditions The UE must support Intra-LTE ANR capability (that is, the UE capability & related feature group indicator bits are set to 1). Activation Procedure To activate this feature, do the following.

Run CHG-SONFN-CELL and set ANR_ENABLE to Manual or Auto. Run CHG-SON-ANR and set NR_ADD_EVENT to anrMrBased or bothMrBased to enable Scheduled ANR functionality.

Run CHG-SONFN-CELL and set ANR_UE_SEARCH_RATE_TOTAL to greater than 0.

Run CHG-SONFN-CELL and set ANR_UE_SEARCH_RATE_INTRA_FREQ to greater than 0 for Intra-Frequency Scheduled ANR functionality.

Run CHG-SONFN-CELL and set ANR_UE_SEARCH_RATE_INTER_FREQ to greater than 0 for Inter-Frequency Scheduled ANR functionality

Run CHG-EUTRA-FA and set the concerned E-UTRA FA‟s ANR_UE_SEARCH_RATE to greater than 0.

Run CHG-DRX-INF and set DRX_CONFIG_SETUP to Drx_Config_Setup or Drx_Config_reportCGI.

Run CHG-SON-ANR and set GBR_REPORT_CGI_OPTION to Allow to enable ANR function for UE with GBR Bearer (for example, QCI = 1).

1 The eNB chooses an UE for Scheduled Intra-LTE ANR by ANR UE selection rules.

2 In case that the Intra-LTE ANR UE is selected, the eNB configures ANR specific measurement configuration for the UE (at this time, measurement duration timer is started in the eNB).

3 The UE transmits measurement report to the eNB based on ANR specific measurement configuration.


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4 When the eNB receives non-neighbor E-UTRA cell from the UE, the eNB requests cell global identity to the UE (using reportCGI configuration).

5 If the eNB successfully obtains the non-neighbor E-UTRA cell‟s CGI from the UE, the eNB registers the new E-UTRA cell into the own neighbor DB.

6 The eNB removes ANR specific measurement configuration for Scheduled ANR from the UE when the measurement duration timer is expired. (For mobility based Intra-LTE ANR) In case of the UE receives handover related measurement report from the UE, the eNB perform from 4) to 5) steps. Deactivation Procedure Run CHG-SONFN-CELL and set ANR_ENABLE to Off.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. This table describes SON property for NRT auto-configuration in LSM. Parameters

Description

R Count

The number of neighbor cells used to calculate the inter-site distance for Initial NRT, PCI, RSI auto-configuration.

NRT Type

Criteria for determining the effective distance used to generate the initial NRT. It can be set to minimum, average, or distance. Distance: Use of NRT Limit Distance as effective radius Average: Use of R multiplied by NRT Multiple as effective radius where R is the distance obtained by averaging the inter-site distance with the neighbor cells in the nearest order (The number of neighbor cells is R Count). Minimum: Use of R multiplied by NRT Multiple as the effective radius where R is the distance with nearest neighbor cell.

NRT Size

The number of neighbor cells that can be included in the initial NRT.

NRT Multiple

The coefficient which is multiplied to either the average distance of the cells as many as R Count or the distance of the nearest neighbor cell.

NRT Limit Distance

The maximum distance to the neighbor cell that can be included in the Initial NRT.

Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-CELL/RTRV-SONFN-CELL Parameters

Description

ANR_ENABLE

The parameter is used to control the Intra-LTE Automatic Neighbor Relation(ANR) operation in three modes. Off: The Intra-LTE ANR function is not performed (NR ranking calculation is performed). Manual: Operator approval is required for NR deletion. Other ANR functions are performed automatically.


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Description Auto: All ANR functions are performed automatically.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-ENB/RTRV-SONFN-ENB Parameters

Description

SON_X2_MGMT_ENABLE

The flag controlling whether the automatic X2 interface management function is performed or not. Off: The automatic X2 interface management function is not performed. Auto: The automatic X2 interface management function is performed (X2 ranking calculation and the size management of X2 Neighbor Relation Table (NRT)).

NR_X2_BLACK_ENABLE

The flag controlling whether the automatic X2 interface blacklisting function is performed or not. (Prerequisite: SON_X2_MGMT_ENABLE = Auto) Off (0): The automatic X2 interface blacklisting function is not performed. Auto (1): The automatic X2 interface blacklisting function is performed.

NR_X2_RE_ENABLE

The flag controlling whether the automatic X2 interface restore function is performed or not. (Prerequisite: SON_X2_MGMT_ENABLE = Auto) Off (0): The automatic X2 interface restoring function is not performed. Auto (1): The automatic X2 interface restoring function is performed.

Parameter Descriptions of CHG-SONFN-CELL/RTRV-SONFN-CELL Parameters

Description

ANR_UE_SEARCH_RATE_TO TAL

The total searching rate of UE which performs the Automatic Neighbor Relation (ANR) measurement for intra-frequency EUTRAN neighbor cells in the periodic neighbor cell adding function with a specific schedule.

ANR_UE_SEARCH_RATE_INT RA_FREQ

The searching rate of UE which performs the Automatic Neighbor Relation (ANR) measurement for intra-frequency EUTRAN neighbor cells in the periodic neighbor cell adding function with a specific schedule.

ANR_UE_SEARCH_RATE_INT ER_FREQ

The searching rate of UE which performs the Automatic Neighbor Relation (ANR) measurement for inter-frequency EUTRAN neighbor cells in the periodic neighbor cell adding function with a specific schedule.

ANR_MEAS_DURATION_INTE R_FREQ

The duration of Automatic Neighbor Relation (ANR) measurement of UE to add E-UTRAN inter-frequency neighbor cells in the periodic neighbor cell adding function. If the timer set to this parameter value is expired, serving cell releases the corresponding setting of ANR measurement for the UE.

Parameter Descriptions of CHG-SON-ANR/RTRV-SON-ANR Parameters

Description

MAX_NRTSIZE

The maximum size of Neighbor Relation Table (NRT) which includes EUTRAN neighbor cells, for a given served cell. The number of Neighbor Relations (NRs) in NRT should be managed so that it cannot exceed this parameter value.

LSM_USAGE_FLAG

The flag controlling whether LTE System Manager (LSM)-based new neighbor cell adding function is performed or not. False (0): The LSM-based new neighbor cell adding function is not


652


Description performed. True (1): The LSM-based new neighbor cell adding function is performed.

RANK_PERIOD

The period for ranking calculation of Neighbor Relations (NRs), used in the periodic NR ranking calculation function.

FILTERING_COEFF

The Infinite Impulse Response (IIR) filtering coefficient used in the calculation of current rank of neighbor cell in the periodic NR ranking calculation function. The current rank is obtained based on the previous rank and the statistics of Measurement Report (MR) for the current period, with this parameter.

NR_DEL_FLAG

The flag controlling whether the function for deleting unnecessary Neighbor Relations (NRs) is performed or not. If the statistics of Measurement Report (MR) collected during a specific threshold time (TH_TIME_NR_DEL) for a given NR is below a specific threshold (TH_NUM_MR_NR_DEL), the NR is determined as unnecessary. False (0): Deletion of unnecessary NRs is not performed. True (1): Deletion of unnecessary NRs is performed.

TH_TIME_NR_DEL

The threshold of time duration for collecting statistics, used in Neighbor Relation (NR) removal function which deletes NRs being unnecessary or degrading the Handover (HO) performance (Unit: day). If the statistics of Measurement Report (MR) collected during a specific threshold time (TH_TIME_NR_DEL) for a given NR is below a specific threshold (TH_NUM_MR_NR_DEL), the NR is determined as unnecessary. If, for a given NR, the HO attempt count collected during a specific threshold time (TH_TIME_NR_DEL) exceeds a specific threshold (TH_HO_PREP_SUC_NR_DEL) and the HO success rate is below a specific threshold (TH_HO_SUC_RATE_NR_DEL), the NR is determined as degrading the HO performance.

TH_NUM_MR_NR_DEL

The threshold of statistics for Measurement Report (MR), used for deleting unnecessary Neighbor Relations (NRs). If the statistics of MR collected during a specific threshold time (TH_TIME_NR_DEL) is below this parameter value, the NR is determined as unnecessary. The statistics of MR for a given neighbor cell means the number of MR messages for this cell, triggered by HO or periodic neighbor cell adding function.

WRONG_NR_DEL_FLAG

The flag controlling whether the function of deleting Neighbor Relations (NRs) degrading the handover (HO) performance is performed or not. False (0): Deletion of NRs degrading the HO performance is not performed. True (1): Deletion of NRs degrading the HO performance is performed.

TH_HO_SUC_RATE_NR_DEL

The Handover (HO) success rate threshold value used for deleting the Neighbor Relations (NRs) which degrade the handover (HO) performance. If the HO success rate for a specific NR at the instant of NR ranking is below this value, the NR is deleted from NRT (or blacklisted).

TH_HO_PREP_SUC_NR_DEL

The Handover (HO) preparation success count threshold used for deleting the Intra-LTE Neighbor Relations (NRs) which degrade the HO performance. If the HO preparation success count collected exceeds this parameter value, it is determined that the HO preparation success count condition is satisfied for deleting the NRs which degrade the HO performance.

MAX_X2_NRT_SIZE

The maximum size of X2 Neighbor Relation Table (X2 NRT). The number of X2 Neighbor Relations (NRs) in X2 NRT should be managed so that it cannot exceed this parameter value.

DEFAULT_VALUE_X2

For a given new neighbor eNB added in the X2 Neighbor Relation Table (X2 NRT), the default value set to the current X2 rank of this eNB at the first X2 ranking calculation time.


653


Description

WEIGHT_TH_X2_BLACK

This parameter is the weight factor to decide the threshold for unnecessary X2 NR blacklisting function.

BLACK_LIST_MGMT_FLAG

This parameter is the flag controlling whether the function for Intra-LTE NR black list management is performed or not. False (0): Black list management function is not performed. True (1): Black list management function is performed.

TH_HAND_IN_4_BLACK_2_W HITE

This parameter is the threshold value used for determining transition from black NR to white NR.

WEIGHT_TH_X2_RE

This parameter is the weight factor to decide the threshold for unnecessary X2 NR restoring function.

NR_ADD_EVENT

This parameter is the flag controlling the operational mode of Intra-LTE ANR. hoMrBased (0): Intra-LTE ANR is performed based on handover event MR. anrMrBased (1): Intra-LTE ANR is performed based on ANR specific event MR. bothMrBased (2): Intra-LTE ANR is performed based on handover/ANR specific event MR.

A2_INTER_FREQ_ANR_FLAG

This parameter is the flag controlling whether to use the A2 event when eNB requests inter-frequency measurement to the UE for Scheduled ANR in Intra-LTE ANR. False (0): A2 event is not used. True (1): A2 event is used.

GBR_REPORT_CGI_OPTION

This parameter is the flag controlling whether to configure reportCGI to the UE with GBR bearer for Intra-LTE ANR purpose. Off (0): reportCGI is not configured. ScheduledAnr (1): reportCGI can be configured for Scheduled ANR. HoEventAnr (2): reportCGI can be configured for HO event based ANR BothAnr (3): reportCGI can be configured for Scheduled and HO event based ANR.

Parameter Descriptions of CHG-ANR-SCHED/RTRV-ANR-SCHED Parameters

Description

ANR_STATE

The flag controlling whether periodic neighbor cell adding operation is performed or not. Inactive (0): Periodic neighbor cell adding operation is not performed. Active (1): Periodic neighbor cell adding operation is performed.

DAY

The day of the week on which the periodic neighbor cell adding operation is performed.

HOUR

The start hour on which the periodic neighbor cell adding operation is performed.

MINUTE

The start minute on which the periodic neighbor cell adding operation is performed.

DURATION

The duration of time on which the periodic neighbor cell adding operation is performed (Unit: hour).

Parameter Descriptions of CHG-EUTRA-FA/RTRV-EUTRA-FA Parameters

Description


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Description

ANR_UE_SEARCH_RATE

The searching rate of UE which performs the Automatic Neighbor Relation (ANR) measurement for corresponding carrier in the periodic neighbor cell adding function with a specific schedule (Unit: %).

MIN_NRT_SIZE_CARRIER

This parameter is the minimum number of valid neighbor shuld be existed by carrier. This parameter's purpose is to prevent too much deletion for a specific carrier in neighbor relation optimizing operation and to support Son Load Balancing function's normal operation.

ANR_ALLOW

The flag contolling whether new neighbor cell adding function for corresponding carrier is performed or not, in the Automatic Neighbor Relation (ANR) function. no_use (0): New neighbor cell adding function for corresponding carrier is not performed use (1): New neighbor cell adding function for corresponding carrier is performed

Parameter Descriptions of CHG-DRX-INF/RTRV-DRX-INF Parameters

Description

QCI

QCI index (Currently used index: 1~9)

DRX_CONFIG_SETUP

Whether to use the DRX. ci_Config_Release: DRX is not used. ci_Config_Setup: normal DRX profile is used in normal status and reportCGI DRX profile is used in reportCGI status. ci_Config_reportCGI: DRX is not used in normal status and reportCGI DRX profile is used in reportCGI status.

ON_DURATION_TIMER_REP ORT_CGI

Timer to monitor the PDCCH in DRX mode when reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on.

DRX_INACTIVITY_TIMER_ REPORT_CGI

Timer to monitor PDCCH in DRX mode when inter-RAT reportCGI status. Value is the number of PDCCH sub-frames: psf1 for 1 PDCCH subframe, psf2 for 2 PDCCH sub-frames and so on.

DRX_RETRANSMISSION_TIM ER_REPORT_CGI

The timer used to monitor PDCCH in DRX mode when inter-RAT reportCGI status.

LONG_DRXCYCLE_START_O FFSET_TYPE_REPORT_CGI

The long DRX cycle and drx start offset values to run onDurationTimer in DRX mode when inter-RAT reportCGI status. The unit of the long DRX cycle is a sub-frame. If the short DRX-Cycle is set to a value, this parameter is set to a multiple of the short DRX-Cycle. The DRX start offset is set to an integer. For the TDD, DL sub-frame or UL sub-frame can be set.

Parameter Descriptions of CHG-TIMER-INF/RTRV-TIMER-INF Parameters

Description

EUTRA_REPORT_CGI_MR_T O_WAIT

The time to wait for reception of reportCGI MeasurementReport (Intra-LTE)

Parameter Descriptions of CHG-PLMNANR-ENB/RTRV-PLMNANR-ENB Parameters

Description

ANR_TARGET_MCC

It is the MCC for defining Primary PLMN of Neighbor eNB. It is used to determine the ANR operation per-PLMN about the eNB including the PLMN


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Description ID in Global eNB ID.

ANR_TARGET_MNC

It is the MNC for defining Primary PLMN of Neighbor eNB. It is used to determine the ANR operation per-PLMN about the eNB including the PLMN ID in Global eNB ID.

USE_NBR_NO_X2

It is used to allow/block X2 connection to the neighbor eNB with primary PLMN ID which is configured in this PLD when the NBR eNB is added by ANR function. It is noted that default operation for the unregistered PLMN (if the PLMN ID is not defined in this PLD or PLMN status is N_EQUIP) is to allow to make X2 connection. no_use: If the useNBRNoX2 is CI_no_use for the registered target PLMN ID, X2 connection setup is allowed. That is, primary PLMN of the newly registered neighbor eNB added by ANR function is matched to the target PLMN ID, eNB will set NO_X2 = false for this newly added eNB to allow to setup X2 connection. Also, if the eNB receives X2 Setup Request from the unknown eNB, it will add this eNB as the new neighbor eNB and accept to make X2 connection by setting NO_X2 = False. use: If the useNBRNoX2 is CI_use for the registered target PLMN ID, X2 connection setup is blocked. That is, primary PLMN of the newly registered neighbor eNB added by ANR function is matched to the target PLMN ID, eNB will set NO_X2 = True for this newly added eNB to block to setup X2 connection. Also, if the eNB receives X2 Setup Request from the unknown eNB, it will add this eNB as the new neighbor eNB and reject X2 connection by setting NO_X2 = True.

Parameter Descriptions of CHG-NBR-ENB/RTRV-NBR-ENB Parameters

Description

CURRENT_X2_RANK

The current X2 rank of corresponding EUTRAN neighbor eNB.

PREVIOUS_X2_RANK

The previous X2 rank of corresponding EUTRAN neighbor eNB.

NO_X2_HO

This parameter is the flag to determine whether X2 or S1 HO will be used between X2 NR only when X2 status is in service. False (0): X2 HO will be used for X2 NR HO True (1): X2 HO will not be used. S1 HO will be used X2 NR HO

Parameter Descriptions of CHG-PLMNBLACK-LIST/RTRV-PLMNBLACK-LIST Parameters

Description

USED_FLAG

It shows whether PLMN is used or not. no_use: not used use: used

MCC

It refers to Mobile Country Code(MCC). Enter a three-digit number with the numbers in each digit being 0~9.

MNC

It refers to Mobile Country Code(MCC). Enter a three or two-digit number with the numbers in each digit being 0~9.

EUTRA_BLOCK_FLAG

This attribute indicates whether or not to apply the PLMN blacklist about the E-UTRA neighbor. False: Not apply the PLMN Blacklist to the E-UTRA neighbor.


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Description True: Apply the PLMN Blacklist to the E-UTRA neighbor.

Parameter Descriptions of CHG-NBR-EUTRAN/RTRV-NBR-EUTRAN Parameters

Description

CURRENT_RANK

This parameter is the current priority of the neighbor cell.

PREVIOUS_RANK

This parameter is the previous priority of the neighbor cell.

Parameter Descriptions of CHG-NBRDEL-CAUSE/RTRV-NBRDEL-CAUSE Parameters

Description

NBR_DEL_CAUSE_FLAG

This parameter shows whether or not the feature to delete the neighbor with handover issue is used. False (0: the feature to delete the neighbor with handover issue is not used. True (1): the feature to delete the neighbor with handover issue is used.

S1_UNKNOWN_PLMN_TH

This parameter is S1AP Unknown PLMN failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

S1_HO_FAIL_IN_TARGET_SY S_TH

This parameter is S1AP Handover Failure In Target EPC/eNB Or Target System failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

S1_RELOC_PREP_EXPIRY_T H

This parameter is S1AP TS1RELOCprep Expiry failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

X2_S1_CELL_NOT_AVAILABL E_TH

This parameter is X2AP or S1AP Cell Not Available failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

S1_UNKNOWN_TARGET_ID_ TH

This parameter is S1AP Unknown Target ID failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

X2_RELOC_PREP_EXPIRY_T H

This parameter is X2AP TRELOCprep Expiry failure value which indicates the threshold to delete a neighbor in case of consistent handover failure.

Parameter Descriptions of CHG-X2GTDBAND-INFO/RTRV-X2GTDBAND-INFO Parameters

Description

STATUS

Whether or not X2 Guaranteed Band Indicator data is in use.

BAND_INDICATOR

The Band Indicator for which the min number of X2 Links should be maintained.

MIN_X2_NRT_SIZE

The min number of X2 Links that should be maintained for the Band Indicator.

Parameter Descriptions of CHG-MSGAP-INF/RTRV-MSGAP-INF Parameters

Description

GAP_RELEASE_FOR_REPOR T_CGI

This parameter is the flag controlling whether to release measurement gap or not when eNB commands to perform reportCGI to UE. This flag is only used when reportCGI is configured with DRX False (0): eNB does not release measurement gap when configuring


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Description reportCGI to UE. True (1): eNB releases measurement gap when configuring reportCGI to UE

GAP_USE_FOR_REPORT_CG I

This parameter indicates whether to use the measurement gap for reportCGI in case that si-RequestForHo and DRX cannot be configured for reportCGI. False (0): measGap for reportCGI is not configured. True (1): measGap for reportCGI is configured.

GAP_PATTERN_FOR_REPOR T_CGI

This parameter is the measurement gap pattern used for reportCGI. A gap pattern is used to configure gap offset during MeasGapConfig configuration. If it is gapPattern0, a gap offset (0-39) corresponding to Gap Pattern ID 0 is configured. If it is gapPattern1, a gap offset (0-79) corresponding to Gap Pattern ID 0 is configured. This parameter is applied only when the GAP_USE_FOR_REPORT_CGI is set to True.

Counters and KPIs Tables below outline the main counters associated with this feature Counters related with Intra-LTE ANR function Family Display Name

Type Name

Type Description

HO

IntraEnbPrepSucc

The number of Intra-eNB handover preparation success to intra-eNB neighbor cell

IntraEnbSucc

The number of Intra-eNB handover execution success to intra-eNB neighbor cell

InterX2OutPrepSucc

The number of X2 HO preparation success to inter-eNB neighbor cell

InterX2OutSucc

The number of X2 HO execution success to intereNB neighbor cell

InterS1OutPrepSucc

The number of S1 HO preparation success to inter-eNB neighbor cell

InterS1OutSucc

The number of S1 HO execution success to intereNB neighbor cell

Family Display Name

Type Name

Type Description

STAT_SON_INTEGRATED

IntraLTEHoSuc_Integ

For all X2 and S1 Ho success cases. If the Cause of the UE Context Release Command is not ‘HO Success’, counter shall not be increased.

Tables below outline the main Key Performance Indicators (KPIs) associated with this feature KPIs related with Intra-LTE ANR function Family Display Name

KPI Name

Description

Mobility

EutranMobilityHOIntra

Intra-eNB handover success rate of E-UTRAN mobility

EutranMobilityHOX2Out

X2 handover success rate of E-UTRAN mobility


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Chapter 8 SON Family Display Name Success Rate

KPI Name

Description

EutranMobilityHOS1Out

S1 handover success rate of E-UTRAN mobility

CallDropRatio

Call drop rate

REFERENCE [1] 3GPP TS 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 12). [2] 3GPP TS 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 12). [3] 3GPP TS 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions. [4] 3GPP TS 32.500: E-UTRAN; Concepts & Requirements. [5] 3GPP TS 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases. [6] 3GPP TS 36.413: E-UTRAN; S1 Application Protocol (Release 12). [7] 3GPP TS 36.423: E-UTRAN; X2 Application Protocol (Release 12).


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LTE-SO0301, PCI AutoConfiguration INTRODUCTION The Samsung Physical-layer Cell Identity (PCI) optimization provides functions such as auto PCI configuration for initial PCI allocation during network installation, PCI collision, confusion detection, and auto PCI optimization for PCI reallocation. There are 504 PCIs in the LTE system. PCIs consist of 168 unique physical layer cell identity groups, N_{ID}^{(1)} and three physical layer identities within the physical layer cell identity group, N_{ID}^{(2)}. It is configured based on this formula: N_{ID}^{Cell} = 3 * N_{ID}^{(1)}+ N_{ID}^{(2)}…………………(1) Where:

N_{ID}^{(2)} is related to cell-specific reference signal location pattern. N_{ID}^{(1)} is a sequence number which is used N_{ID}^{Cell} with N_{ID}^{(2)} PCIs are used in synchronization and reference signal generation, which are involved in cell selection, handover and channel estimation procedures. According to 3GPP specification there are 504 unique physical-layer cell identities. The physical-layer cell identities are put together into 168 unique physical-layer cell-identity groups, and each group contain three unique identities. The Samsung PCI optimization policy is as follows:

PCI allocated should satisfy the collision-free and confusion-free condition. PCI allocated should reduce inter-RS (cell-specific reference signal) interference. PCI of the cell with higher E-UTRAN Cell Identity (ECI) is changed, if PCI conflict is detected by X2 message.

PCI of the cell reporting PCI collision is changed, if PCI collision is detected by RRC Connection Re-establishment Request message.

BENEFIT You can reduce CAPEX/OPEX required for network installation and expansion. This feature guarantees improved mobility between cells to end-users.

DEPENDENCY Interface & Protocols eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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To detect PCI conflict between two cells in different eNBs, X2 interface must be connected.

LIMITATION To use Initial PCI auto-configuration and PCI re-initialization function, location information of the cell should be configured.

If antenna azimuth/beamwidth of each cell is not configured, the performance of PSS Interference based PCI allocation/reallocation function may be degraded.



If Initial PCI Auto-configuration function is used for multiple newly added eNBs, the EMS may allocate the same PCI to multiple newly added cells.

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Interdependencies between Features: Interdependent Feature: LTE-SO0201, Intra-LTE ANR Intra-LTE ANR feature optimizes NRT (Neighbor Relation Table) by automatically adding new neighbor cells based on UE (User Equipment) measurement reports and deleting neighbor cells based on handover statistics. Performance and Capacity PCI Auto-configuration automatically detects PCI conflict and resolves it. This guarantees reliable mobility of the UEs when the UEs are moving between cells. Interfaces If PCI of a cell is changed by PCI Auto-configuration feature, the results are propagated by X2 eNB Configuration Update message.

FEATURE DESCRIPTION The Samsung PCI optimization operates in the eNB's SON agent and EMS's SON manager. The overall structure is as follows:


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The operation of each entity in this architecture is as follows: EMS PCI Management Function in SON Manager

Create initial PCI Performs a PCI reallocation upon receiving the PCI collision/confusion notify information message.

PCI reallocation cell selection Transmits a new PCI to the eNB of the cell whose PCI is changed. Transmit timer triggering notify information to eNB which has smaller ECI. eNB: SON Agent PCI Management Function oTransmits a notify information message to the EMS and stores it in the DB when PCI collision/confusion is determined. oTimer running for waiting PCI reconfiguration when EMS trigger timer oWhen timer expires, transmit a new PCI allocation message to the EMS. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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PCI collision/confusion Detection Function oDetects PCI collision/confusion using the X2 SETUP REQUEST, X2 SETUP RESPONSE, eNB CONFIGURATION UPDATE, and RLF INDICATION messages received from the call processor. oDetects a PCI collision/confusion using the ECGI information received from the neighbor detection function.

PCI Auto-configuration The PCI auto-configuration function is performed in the EMS. It aims to allocate PCIs based on the distance between cells to avoid PCI collision/confusion. It selects the reference distance from the cells that allocates PCI, and then allocates PCIs, assuring that all cells belonging to the same EMS within the reference distance avoid PCI collision/confusion. Figure below depicts a brief overview of the PCI configuration.

There are two kinds of considering situation to avoid when PCI auto-configuration is performed.

PCI collision oDefinition: where two cells with adjacent coverage use the same FA and PCI. oProblem: handover ambiguity occurs because the UE existing on the border between the two cells cannot distinguish the serving cell from the neighbor cell. Figure below depicts PCI collision:


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PCI confusion oDefinition: where two cells adjacent to the coverage of the serving cell (cell B) use the same FA and PCI. oProblem: handover ambiguity occurs because the cell B is cannot distinguish which is the target cell. Figure below depicts PCI confusion:

The PCI auto-configuration involves the following operations:

1 The EMS receives latitude/longitude coordinates of the installed cell from the operator or the GPS during eNB installation.

2 The EMS calculates the reference distance (D) 3 N_{ID}^{(2)} is allocated first for the PCI allocation cell. For the cell existing at the same location, ensure N_{ID}^{(2)} is not in neighborhoods with it by using its cell number.

4 Select PCIs other than the ones used by all cells that use the same EMS within the reference distance from the PCI allocation cell. If the cells within the reference distance (D) use all allocable PCIs, select PCIs by using the maximum reuse distance. Maximum reuse distance means the maximum distance between cells which the same PCI can be reused within D. Distance Calculation for PCI Auto-configuration PCIs are collected within the reference distance (D) to avoid PCI conflicts and D is calculated as follows: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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D = MAX (R * R_Multi, LimiDist) R = Inter-site distance R_multi = [0, 4] LimitDist = [0, 100] km The cells within reference distance (D) will be considered for new installed cell‟s PCI auto configuration. The EMS calculates the reference distance (D) with three parameters R, R_multi, and LimitDist above. The following is explanation of parameters for PCI auto-configuration:

R is the inter-site distance, however, inter-site distance from a cell to another cell can have all different value. So, Samsung support three different kinds of Inter-site distance R calculation mode. Inter-site distance R is calculated based on the selection below. ominimum: using R as distance of the nearest neighbour cell odistance: criteria of fixed distance oaverage: using R as average distance with cell inside LimitDist Operators can change the inter-site distance mode value in the EMS SON Property GUI PCI Type menu.

R_multi is a scaling parameter for expansion Inter-site distance R. Operators can adjust the number of cells inside the distance D with R_multi by changing R_multi value in the EMS SON Property GUI PCI multiple menu.

LimitDist is the minimum of the effective Distance D when allocating PCI. Even through dense deployment area, each cell should consider minimum distance LimitDist for PCI auto-configuration. Operators can change LimitDist value in the EMS SON Property GUI PCI LimitDist menu.

PSS Interference Avoidance The assignment of PCI value to a cell is defined with two parameters: physicallayer cell identity groups and physical layer identity. Before the EMS assigns the unique PCI value to a cell, it chooses PSS value for each cell to reduce inter-RS interference between target and neighboring cells. During the deployment of a new cell, the EMS updates NR and sorts cells in accordance with their distance. The cells belong to SameLocationCellGroup if they are co-allocated and served by the same eNB. PSS value for each cell is defined by one of three numbers: 0, 1 and 2. Using six possible combinations the EMS assigns PSS value to a cell within the bulk of three neighboring cells. As a result, the EMS obtains the sets of PSS values, which are called PSS sets, for SameLocationCellGroup. Figure below depicts PSS interference avoidance for three co-located cells.


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For each PSS set, the EMS calculates the cost function which is based on interference, by-turn the interference is calculated with respect to pathloss and gain. The PSS set with the minimal cost function is chosen as an optimal variant and be used for further calculation of PCI value. Figure below depicts the PSS interference avoidance for four and more co-located cells.

In the case of more than three cells attached to one eNB, the EMS creates another SameLocationCellGrop that is used to generate PSS value for other cells. The EMS calculates the cost function for each PSS set in each SameLocationCellGroup and orders them in accordance with the cost function for each SameLocationCellGroup. The obtained set of PSS values for all cells attached to one eNB is used to calculate further PCI values. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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PCI Optimization PCI Collision/Confusion Detection The PCI collision/confusion detection function is performed in the SON agent of eNB. There is a list of PCI collision/confusion detection occurrence situation & pre-requisite as below. When PCI collision/confusion is detected, the SON agent reports to the SON manager of the EMS on the occurrence of PCI conflict and the 2TierNRT creation.

PCI conflicts detection occurrence oPCI change by operator oNew neighbor cell enrolled by ANR operation and manually added neighbor oX2 message information (FA, PCI, and ECGI) from neighbor eNB

Pre-requisite oNeighbor relation table o2Tier Neighbor relation table A pre-requisite for PCI confusion is that each cell creates and maintains its NRT for handover. A serving cell is only aware of its immediate neighbor cell (that is, NRT) and not its neighbor to neighbor PCI number (that is, 2TierNRT). PCI confusion occurs as a result of 2TierNRT PCI clash hence, a cell also needs to create a list of neighbor to neighbor cell PCI value, to detect PCI confusion. When a cell receives a X2 message from its immediate neighbor cell, it updates 2TierNRT PCI values, which is used for PCI confusion detection and deny PCI list, for new PCI allocation. Figure below depicts more details about PCI collision/confusion detection:


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1 If the served cell or neighbor cell information is changed, X2 eNB configuration update message is transferred.

2 Based on the X2 eNB configuration update message, the eNB updates NRT and 2-tier NRT of its served cell and checks if there is PCI conflict.

3 If PCI conflict is detected, the eNB reports it to the EMS with 2-tier PCI list. 4 The EMS selects a new PCI based on the 2-tier PCI list. 5 The EMS allocates the new PCI to the cell involved in PCI conflict. PCI collision detection based on UE mobility The PCI collision detection function based on UE mobility focuses on the resolution of PCI conflict between neighboring eNBs when UE moves from one cell coverage to other one. By using this function, the PCI collision can be detected even though there is no neighbor relation between two adjacent cells. UE cannot successfully perform HO: RLF occurs due to RF degradation and UE tries to synchronize with the target cell again. The UE requests RRC Connection Reestablishment to the target cell but the request is rejected, because the target cell does not have the UE Context.

PCI collision detection occurrence oUE moves from the serving cell to the target cell oUE experiences RLF event oUE tries RRC Re-establishment (RRE) procedure in the target cell oThe eNB of the target cell can detect PCI that can be potentially involved in the PCI collision

Condition for PCI collision detection There are three defined conditions that control PCI collision detection: oCondition 1: PCI in UE-Identity and PCI of the cell that receives Reestablishment request from UE are the same. oCondition 2: C-RNTI in UE-Identity has already existed in the cell that receives Re-establishment request from UE oCondition 3: Short MAC-I in UE-Identity is not identical to Short MAC-I that is calculated by the target cell PCI collision is detected if condition 1 is satisfied and condition 2 is not satisfied, or all three conditions are satisfied at the same time.

Pre-requisite SON Manager at EMS differentiates PCI conflict message and PCI collision notification. Figure below depicts Samsung Femto PCI collision detection based on UE mobility.


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Once SON Manager at LSM receives the notification of the PCI collision from eNB, the SON manager reallocates the PCI of the cell reporting PCI collision notification. To exclude the redundancy of notification of PCI collision LSM saves PCI collision event and waits until PCI reconfiguration time period starts. In this case, LSM begins to resolve PCI collision one by one during PCI reconfiguration period. If another timer that relates to PCI confusion event is running, LSM turns off the timer. PCI Conflict Detection based on RLF INDICATION Message In case that served cell (Cell A) of Samsung eNB (eNB 1) receives RRC Connection Reestablishment Request message from a UE, eNB 1 checks if it has the context of the UE which sent RRC Connection Reestablishment Request message. If eNB 1 does not have the UE Context, it transmits RLF INDICATION message to the all cells which have the same PCI as the PCI in RRC Connection Reestablishment Request message. Served cell (Cell B) of eNB 2 which receives RLF INDICATION message from eNB 1 determines that there is PCI conflict and transmits PCI conflict event to the SON Manager in the EMS if following conditions are satisfied.

Re-establishment cell ECGI (Cell A) in RLF INDICATION message is not included in its own NRT.

A cell having the same PCI/EARFCN with Re-establishment cell is already registered in its own NRT. Once the SON Manager in the EMS receives PCI conflict detection event from Cell B of eNB 2, it determines the PCI reallocation cell based on ECI information and reallocates a new PCI to the cell based on 2TierNRT information. Figure below depicts the procedure of PCI conflict detection based on RLF INDICATION message.


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PCI Reallocation Cell Selection Because PCI conflict always happens in pair, PCI reallocation should change only one PCI. When the EMS receives the PCI conflict report from the eNB, it determines one cell to change PCI based on ECI. The EMS selects the cell having higher ECI between two cells contained in the PCI conflict report. The EMS tries to change the PCI of the selected cell and instructs the cell with lower ECI to start the timer for triggering the request for a new PCI. If the cell with a higher ECI successfully changes its PCI, then the eNB managing the cell sends its neighbor eNBs the X2 message which informs the change of the PCI. If the eNB managing the cell with a lower ECI receives this X2 message, the cell recognizes the resolution of the PCI conflict and then cancels the timer operation. Otherwise, the timer will be expired and the cell with a lower ECI will recognize that the PCI conflict is not resolved. Then, the cell with a lower ECI requests the EMS to reallocate a new PCI. If EMS receives UE mobility based PCI collision detection event, it selects the cell which reported PCI collision detection event as PCI reallocation cell.


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PCI Reallocation Upon receiving the report of the PCI conflict, the SON manager of the EMS selects the target cell for PCI reallocation. PCI reallocation procedures are performed once the PCI reallocation cell is selected. There are two types of PCI reallocation methods: PLI Maintenance-based and PSS Interference-based, from which the operator can make a selection.

PLI Maintenance-based PCI reallocation (default) The NRT based PCI reallocation method is as follows;

d2TierNRT PCI list is reported from eNB. eMake available PCI pool by excluding the PCIs in the 2TierNRT from the PCI whitelist.

fReconfigure a new PCI from available PCI pool. PSS Interference based PCI reallocation The PSS interference based PCI reallocation method selects the PSS value in the way to minimize PSS interference from the neighbor cells. Once PSS values are chosen, they are used to calculate the PCI values for each concrete cell.

PCI Optimization Operation Tool in the EMS PCI Reservation PCI Auto-configuration provides a function for setting PCI whitelist in order to prevent the assignment of specific PCI, a whitelist can be set. The PCI whitelist can be set in the SON Property window in EMS.

PCI White List: The PCI White List values can be set range from single to multiple. For example, 0,100-500 means PCI can be set 0 and from 100 to 500. Time to Trigger PCI Change After detection of PCI conflict, the eNB reports this event to the EMS. The EMS saves PCI conflict event and waits until PCI reconfiguration start time start. When the EMS meets PCI reconfiguration start time then begin to resolve PCI conflict event one by one during PCI reconfiguration period. PCI reconfiguration start time and period can be set in the SON Property in the EMS.

PCI reconfiguration start time is to schedule time for change conflict PCI. PCI reconfiguration period is the period for change conflict PCI.



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Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-SONFN-ENB and set PCID_ENABLE_ENHANCED to Manual or Auto or Scheduled. Deactivation Procedure Run CHG-SONFN-ENB and set PCID_ENABLE_ENHANCED to Off.

Key Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Tables below outlines the SON property for PCI auto-configuration in the EMS: Parameters

Description

R Count

The number of Cell to calculate an average of NRT, PCI and RSI. The number of cell for calculations should be equal or less than that of the R count, and also a cell should be within the initDistance. Range: 1~32

PCI Types

A decision criterion of an effective radius on PCI allocations. Distance: A value based on a fixed distance. Average: Use the R value, derived from an average of distances between a PCI and cells. Minimum: Use the R value, derived from a minimum distance between a PCI and the nearest cell.

PCI Multiplication Factors

An increase range for calculating an effective distance on PCI allocations. Range: 1~4

PCI Distance Limits

A minimum effective radius on PCI allocations. Range: 1~100

Initial PCI Configurations

Select an initial PCI allocation algorithm. LocationBased: Without using tier-2 NBR, allocate PCIs based on a distance. PSSInterferenceBased: Allocate PCIs that show the minimum PSS interruption.

PCI Black List

Set PCI Black Lists. Able to setup up to 10 ranges. Unable to use a black list without setup. ex) If you set a range such as 400-503, a PCI within the range will not be allocated.

PCI Reconfiguration Modes

A way to change the cell status after PCI allocations. cellAdminShutDown: Unlock -> Shutting down. cellAdminLock: Unlock -> Locked.

PCI Reconfiguration Timeout

A timeout value on cell status changes. Range: 0~60 minutes

PCI Reconfiguration Methods

Select a PCI reallocation Algorithm. PLIMaintenanceBased: Select a PCI value not used by 2 tier neighbor cells while maintaining PLI. PSSInterferenceBased: Select a PCI value not used by 2 tier neighbor cells while considering PSS interference.


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Description

PCI Reconfiguration Start Time

Execution time for a PCI schedule mode modification. Range: 0~23 hours

PCI Reconfiguration Periods

Periods for scheduled PCI reallocation from start time Range: 1~23 hours

PCI Manual Applications Waiting Time

PCI Manual Application Timeout. Range: 0~4320 in minutes If you input zero or nothing, unable to use a manual application waiting time.

Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-ENB/RTRV-SONFN-ENB Parameter

Description

PCID_ENABLE_ENHANCE D

The Self-Organizing Networks (SON) Physical Cell Identity (PCI) optimization function is controlled in three modes. Off: 2tier PCI list management through X2 monitoring is only performed. Manual: 2tier PCI list management through X2 monitoring and PCI collision/confusion detection is automatically performed. For the PCI reallocation function, PCI for a cell is reallocated with operator approval. Auto: 2tier PCI list management through X2 monitoring and PCI collision/confusion detection, PCI reallocation functions are performed automatically. Scheduled: 2tier PCI list management through X2 monitoring and PCI collision/confusion detection is automatically performed. For the PCI reallocation function, PCI for a cell is automatically reallocated during the pre-defined time set by operator.

PCI_COLLISION_DETECT_ FLAG

This parameter corresponds to the flag for PCI Collision Detection. If the value of the parameter is set 0, pciCollisionDetectionFlag is switched off, if the value of the parameter is set 1, pciCollisionDetection is switched on.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SON-PCI/RTRV-SON-PCI Parameter

Description

TH_PCI_REALLOCATE_LA TENCY

This parameter is the standby time (min) for requesting reallocation of the Physical Cell Identity (PCI). If PCI reallocation is not performed normally during the set time, PCI is reallocated by selecting the other cell involved in the PCI conflict. If the PCI_Reconfiguration_Modes is set to cellAdminShutDown, it is recommended that the value of TH_PCI_REALLOCATE_LATENCY is bigger than PCI_Reconfiguration_Timeout, PCI_Reconfiguration_Modes and PCI_Reconfiguration_Timeout respectively belongs to Self-Organizing Network (SON) Property of Entity Management System (EMS).

Counters and KPIs There are no specific counters or Key Performance Indicators (KPIs) associated with this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 9) [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 9) [3] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [4] 3GPP 32.500: E-UTRAN; Concepts & Requirements [5] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases [6] 3GPP 32.521: E-UTRAN; Self-Organizing Networks (SON) Policy Network Resource Model (NRM) Integration Reference Point (IRP); Requirements [7] 3GPP 32.522: E-UTRAN; Self-Organizing Networks (SON) Policy Network Resource Model (NRM) Integration Reference Point (IRP); Information Service (IS) [8] 3GPP 32.541: E-UTRAN; OAM Requirements for Self Healing Use Cases


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LTE-SO0401, RACH Optimization INTRODUCTION Random Access Channel (RACH) of LTE system is the uplink channel defined in the 3GPP specifications. Depending on the purpose, RACH is classified into two types, the contention based method and the non-contention based method. The contention based method is used for the initial network connection of User Equipment (UE) and the non-contention-based method is used for the connection to the target cell during UE's handover. The actual information transmitted to RACH includes the Zadoff Chu (ZC) sequence whose total length is 839. The LTE System has total 838 ZC sequences (root sequences) for RACH and one ZC sequence can be reused by cyclic shifting. The UE transmits one sequence that is Random Access Preamble (RAP) through Physical Random Access Channel (PRACH) that is the physical channel of RACH to connect initially to the network or attempt a connection to the target cell. Each cell of LTE System configures a RAP set with total 64 consecutive RAPs. As UE selects and uses any RAPs in this RAP set, the number of root sequences used in a cell is determined by the reuse number of one root sequence. A cell can use RAPs by dividing the 64 RAPs into preambles for random access and the dedicated preambles for handover. PRACH resource allocation in LTE System is determined by the PRACH configuration index and freq-offset. The PRACH configuration index indicates its allocation interval and the location of the subframe where it is transmitted. The PRACH freqoffset indicates the location of the physical resource block where it is allocated. The PRACH configuration index is used to determine the reuse number of root sequence. Each RACH resource parameter value can be determined with various combinations by HighSpeedFlag, Zero Correlation Zone Configuration (ZCZC), and Random Access Preamble format. Samsung RACH optimization method aims to minimize UE access delay and maximize UL capacity using various RACH resources. Also, its optimization function is placed in the eNB and EMS respectively. It collects RACH-related statistics, changes parameters using accumulated statistics, and detects RSI collision in eNB. It initially allocates RSI, reallocates RSI during operation, and changing some of RACH parameters in EMS. The configuration function of Samsung RACH optimization automatically determines RSI of the newly installed or grown cell. It sets the reference distance based on location of the installed cell to minimize RSI reuse within the reference distance. The optimization performs below functions: RSI collision detection and reallocation during the operation of the network, optimization of the number of dedicated preambles through the collection of RACH-related statistics, and optimization of the PRACH parameters such as RACH Initial Received Target Power, power ramping step, the number of dedicated preambles, PRACH configuration index, and backoff indicator. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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BENEFIT The operator can reduce previously spent CAPEX and OPEX cost for configuring and managing the RSI and PRACH parameters of LTE cells.

Minimize UE access delay and maximize UL capacity

DEPENDENCY 

Related Radio Technology E-UTRAN (LTE)



Others Application of the RSI configuration requires location information of the cell where the RSI allocation is required. Application of the RACH optimization needs 3GPP Rel.9 UE support including rach-report in UE information message.

LIMITATION 

Self Configuration oThe location based RSI allocation method might cause a RSI collision with a cell that does not use the same EMS. oInitial RSI allocation/RSI re-initialize functions is not performed if cells' latitude/longitude information is not configured.

Self Optimization oRSI allocation method might cause RSI reallocation failure when X2 connection is unable between eNBs. oIn manual apply mode of periodic RACH optimization, statistics cannot be collected during waiting time of operator's manual apply confirmation. In this case, optimization cannot be performed in the next optimization period if the amount of collected statistics is not enough for optimization.

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Performance and Capacity RSI Configuration and RSI Conflict Detection/Reallocation functions of RACH Optimization can improve RACH access performance by avoiding RSI conflict.

Periodic PRACH Parameter Optimization function of RACH Optimization can reduce RACH access delay and improve RACH success rate by adjusting RACH parameters based on RACH statistics.


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Coverage If UEs fail random access due to low preamble transmission power, Periodic PRACH Parameter Optimization function of RACH Optimization adjusts preamble transmission power for random access. This can improve random accesses of UEs in cell edge. Interfaces Interface between eNB and LSM is affected to support RACH Optimization.

FEATURE DESCRIPTION Samsung RACH optimization operates in eNB's SON agent and EMS's SON manager. The overall structure is as follows:

The architecture above shows, Samsung RO functions is executed at eNB‟s SON agent and EMS‟s SON Manager. The operation of each entity in this architecture is as follows: EMS: SON Manager

RSI Management Function oCreate initial RSI eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oPerforms a RSI reallocation upon receiving the RSI collision/confusion notify information message. oRSI reallocation cell selection oTransmits a new RSI to the eNB of the cell whose RSI has been changed. oSupports Manual Apply of RSI reallocation/PRACH parameter change.

RO Parameter Control Function oSupports control of PRACH Configuration Index whenever eNB requests increase of Random Access opportunity. oSupports Manual Apply of optimized PRACH parameters. eNB: SON Agent

RO Statistic Management oIt periodically collects and accumulates the RO-related statistics information from UE and eNB. oIt receives changed RO-related parameters and transmits to the Radio Resource Control (RRC) block.

RO Parameter Control Function oIt changes RO parameters at every RACH parameter decision interval based on accumulated RACH statistics.

RSI Collision Detection Function oIt detects RSI collision through the ENB_CONFIGURATION_UPDATE message received from the call processor. In case of Manual apply option, the optimization/re-allocation process is active as usual but the change in RACH optimization parameter (that is, PRACH Configuration Index) or the reallocation of RSI can only proceed on manual confirmation by the operator.

Self-Configuration Procedure RSI Auto-configuration Samsung RSI auto-configuration is performed in EMS. Subsequently, it aims to allocate RSI that minimizes RS range overlap based on the input distances between cells. The RSI Auto-configuration function operates based on the distances from the cell that requires RSI allocation to other currently operating cells that use the same EMS. The closest cell among those is selected to configure the virtual neighbor. After that, the used root sequence set is calculated using the union of the virtual neighbor and the root sequence that the virtual neighbor is using. RSI is allocated by selecting an available RS range among RS in the whole root sequence pool excluding the used root Sequence set.


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RSI auto configuration involves the following operation:

1 When installing a cell, EMS receives the latitude and longitude coordinates of the installed cell through the operator or GPS.

2 The operator inputs the parameters related to RO of SON Property window of EMS.

3 The distances to the currently operating cells that use the same FA among the cells within the already input NRT distance threshold are calculated, and in order of proximity, the NMax_virtual_NRT numbers of cells are selected to configure the virtual NRT.

4 Used Root Sequence set is configured by collecting root sequences that are used by cells in Virtual NRT.

5 An available RS set is configured in the whole RS pool by excluding the used root sequence set.

6 RSI is allocated by selecting an allocable RS range among the available RS set. At this point, if there is no RS range among the available RS set that satisfies the consecutive RS, eNB includes RS range which is used in the farthest cell into the available RS set, and allocates RSI by selecting an allocable RS range among the available RS set. The eNB repeats step 6) until an RSI can be allocated to the growing cell. As mentioned in document, each cell should use continuous 64 PRACH preambles. PRACH preamble can be reuse based cyclic shift value which defined in 3GPP 36.211 table 5.7.2-2 as below:

N_{CS} for preamble generation (preamble formats 0-3) ZeroCorrelationZoneConfig

0

N_{CS} value Unrestricted Set

Restricted Set

0

15


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Chapter 8 SON ZeroCorrelationZoneConfig

N_{CS} value Unrestricted Set

Restricted Set

1

13

18

2

15

22

3

18

26

4

22

32

5

26

38

6

32

46

7

38

55

8

46

68

9

59

82

10

76

100

11

93

128

12

119

158

13

167

202

14

279

237

15

419

-

N_{CS} for preamble generation (preamble format 4) zeroCorrelationZoneConfig

N_{CS} value

0

2

1

4

2

6

3

8

4

10

5

12

6

15

7

N/A

8

N/A

9

N/A

10

N/A

11

N/A

12

N/A

13

N/A

14

N/A

15

N/A

Preamble format 4 can only be used in some TDD configurations where RACH preamble can be sent in place of UpPTS.

N_{CS} represents the number of cyclic shift eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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High speed flag(Boolean): 0 then use Unrestricted set, 1 then use Restricted set

Root sequence index: initial root sequence index The number of usable preambles that can be generated based on one root sequence is calculated as Floor (length of a root sequence/N_{CS}), and the number of root sequences required for each cell is calculated as Ceil (the number of preambles required per cell/the number of reusable preambles). Length of a root sequence is 839 for preamble format 0~3, and 139 for preamble format 4.

Example) Assume that preamble format = 0, ZCZC = 9, high speed flag = 0. Then, N_{CS} = 59, and the number of usable preamble generated with one root sequence is calculated as Floor(838/59) = 14. That means, one root sequence can be reused for 14 times. As mentioned above one cell needs to have 64 continuous preamble. So, the number of required root sequence for one cell is calculated as Ceil (64/14) = 5. Therefore, 5 root sequences are required. PRACH Position Allocation In LTE system, time/frequency domain resources used for PRACH preamble transmission are as follows:

Time resource: 1~3 subframe of UL frame, position of time domain is determined according to PRACH Configuration Index.

Frequency resource: 6 RBs are occupied, position of frequency domain is determined according to PRACH Frequency Offset. In heterogeneous network environment, interference between high capacity (Macro) cell and small capacity (Indoor Pico, Femto) cell can be occur whenever the same PRACH resource is used in those cells. In order to avoid the interference, in Samsung RACH optimization, different RACH resources are allocated according to eNB Type. eNB Type

PRACH position in frequency domain

MACRO including OUTDOOR PICO

LOW

FEMTO including INDOOR PICO

HIGH

Figure below depicts PRACH separation on heterogeneous LTE network (FD-LTE case).


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Self Optimization The self-optimization function of Samsung RACH Optimization is divided into the event triggering operation and the periodic operation that is based on the statistics information collected during operation. The event triggering RO operation performs required operations when one of the following events is occurred during network operation: i) neighbor relation change, ii) change in root sequence of neighbor cell, iii) activation of RS collision detection and RSI reallocation function (from OFF to ON). The statistics based periodic RO operation controls PRACH InitialReceivedTargetPower, Power Ramping Step, and the number of dedicated preambles, PRACH Configuration Index, and backoff indicator according to periodically obtained RACH-related statistics. RSI Conflict Detection and Reallocation RS Collision Detection RS collision refers to a situation where two cells in neighbor relation use the same FA and RS. In this case, as UE of the two cells selects one preamble in an overlapping RS range and then transmits the PRACH preamble to attempt the initial connection to the network, the probability of contention increases. Therefore, it can degrade the performance of the initial network connection. The RS collision detection function is performed by SON Agent of eNB if RS collision detection and corresponding RSI reallocation function is activated. The RS collision detection function is performed for the following cases: oFor the case of two cells with Inter-eNB neighbor relation: The function operates when cell configuration change message is received through X2 interface. oFor the case of Intra-eNB neighbor cell: The function operates when eNB Configuration update of itself is performed. The SON Agent reports the occurrence of RS collision to SON manager of EMS when RS collision is detected.

RSI reallocation eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The SON manager of EMS receives RS collision reports and selects target cells for RS reallocation. The selection procedure is as follows: o(Case 1) In case that the function is already activated, a cell that has a bigger ECGI is selected as RSI reallocation cell based on the ECIs of RS collision target cells. o(Case 2) In case that the status of RS collision detection and RSI reallocation function for a cell is changed from inactive (OFF) to active (ON), the cell is selected as RSI reallocation cell. Then, SON manager in EMS requests the selected cell to report the neighbor relation list. Meanwhile, for (Case 1), EMS transmits a timer triggering message to a cell with a smaller ECI, and the cell receiving the message operates timer. If timer of the cell with a smaller ECI has expired, the cell considers that RSI reallocation to the cell with a bigger ECI has failed and requests the RSI reallocation again. At this point, if a RSI change message is received from the cell with a bigger ECI after the timer has started running, timer of the cell with a smaller ECI will be stopped. For (Case 2) where the status of RS collision detection and RSI reallocation function for a cell is changed from inactive (OFF) to active (ON), the operation of timer is not performed. The cell that received the NR list request transmits the NR list to EMS. Then, EMS configures used root sequence set by collecting root sequence used by neighbor cells in the NR list. When using the used root sequence set, EMS allocates RSI in the same way for the self-configuration procedure. If no RSI for reallocation is available, EMS does not reallocate RSI. If operation mode of RSI conflict detection/reallocation is set to Auto (RSI_CONFLICT_ENABLE = Auto) for the RSI reallocation cell, the above procedure and application of the new RSI value are performed automatically. On the other hand, if the Manual option is set (RSI_CONFLICT_ENABLE = Manual) for the RSI reallocation cell, EMS notifies operator about the occurrence of RSI collision and necessity of new RSI calculation/apply when EMS receives RSI collision report and selects the RSI reallocation cell. If operator confirms, EMS calculates and reallocates new RSI to the RSI reallocation cell as in above procedure above. Figure below depicts PSI collision in event triggering RO.


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Periodic RACH Optimization There are two aspects of RACH optimization that is number of dedicated preamble and RACH preamble Tx power (Initial ReceivedTargetPower, Power Ramping Step, PRACH configuration index, and backoff indicator). The following figure shows a procedural of RACH optimization.

The terms used in the figure above are defined as follows:

Dedi_Pre_Fail_Ratio_Increase: Average of the dedicated preamble assignment failure ratios higher than the predefined threshold DEDICATED_INCREASE for each hour.


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Dedicated preamble assignment failure ratio = (the number of dedicated preamble assignment failures during 5 min interval) over (the number of HO preparation counts during 5 min interval)

Dedi_Pre_Fail_Ratio_Decrease: Average of the dedicated preamble assignment failure ratios higher than the predefined threshold DEDICATED_DECREASE for each hour.

Avg_Pre_Sent_Num_Increase: The fraction of UE Information Response messages having the value of the field numberOfPreamblesSent higher than the predefined POWER_INCREASE for each hour.

Avg_Pre_Sent_Num_Decrease: The fraction of UE Information Response messages having the value of the field numberOfPreamblesSent higher than the predefined POWER_DECREASE for each hour.

Det_Cont_Ratio_Increase: The fraction of contention detection ratios larger than CONTENTION_INCREASE among contention detection ratios collected during each hour. Contention detection ratio = (the number of UE Information messages with contentionDetected = True during 5 min interval) over (the number of received UE Information messages during 5 min interval)

Det_Cont_Ratio_Decrease: The fraction of contention detection ratios larger than CONTENTION_DECREASE among contention detection ratios collected during each hour. Dedicated Preamble vs. Contention Preamble Adjustment In LTE, preambles in each cell are divided into two categories of preambles as follows:

Random Access Preamble: Preambles used for contention based random access (RRC Idle to RRC Connected, UL data transfer requiring synchronization, RRC Connection Reestablishment).

Dedicated Preamble: Preambles used for non-contention based random access (HO, DL data available requiring synchronization. Since total number of available preambles in each cell is limited (64), an optimal number of dedicated preambles should be determined considering tradeoff between new subscriber accessibility (contention based random access) and HO latency (non-contention based random access). For the purpose, RO control function controls the number of dedicated preamble dynamically. For example-in a lightly loaded cell with low mobility activity, RO control function will split the available preambles to allow for more contention preambles. In a cell with lot of mobility activity and near-capacity user count, RO control function will split the available preambles to have more dedicated preambles. Figure below depicts the general flow of contention vs. dedicated preamble split:


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RO statistics management keeps statistics of dedicated preamble usage and computes a probability of dedicated preamble assignment failure (Dedi_Pre_Fail_Ratio_Increase and Dedi_Pre_Fail_Ratio_Decrease) based on DedicatedPreambles-AssignFail OM. Based on Dedi_Pre_Fail_Ratio_Increase and Dedi_Pre_Fail_Ratio_Decrease, at every RACH optimization period, eNB determines whether to increase/decrease the number of dedicated preambles as follows:

The number of dedicated preambles is increased by a step (step size = 4) if Dedi_Pre_Fail_Ratio_Increase is larger than PROB_DEDICATED_INCREASE.

The number of dedicated preambles is decreased by a step (step size = 4) if Dedi_Pre_Fail_Ratio_Decrease is smaller than PROB_DEDICATED_DECREASE. Otherwise, eNB determines whether to change PRACH Parameters (Initial Received Target Power, Power Ramping Step, PRACH Configuration Index, Backoff Indicator. Figure below depicts the dedicated vs. common preamble split procedure.

Adjustment of PRACH Configuration Index and Power Related Parameters 3GPP spec allows for several configurations that signal the configuration of PRACH channel-via SystemInformationBlockType2. Among the configuration parameters in SIB2, Periodic RACH Optimization automatically adjusts following parameters: Parameter

Description

Allowed Values

powerRampingStep (dB)

Specifying power ramping steps for PRACH preamble transmit power when preamble transmission counter increases.

0, 2, 4, 6

preambleInitialReceivedTargetPowe

Specifying the initial target receiving power

-120, -118, -116, -114, -


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Description of PRACH preambles.

Allowed Values 112, -110, -108, -106, 104, -102, -100, -98, -96, -94, -92, -90

prachConfigIndex

Specifying the PRACH preamble format, subframe sent by preamble, and interval.

Refer to Tables below

Since PRACH is a common uplink control channel, it is wasteful to allocate RACH region in all sub-frames. eNB can choose to declare the location of subframe and the periodicity of PRACH based on prachConfigIndex. The following figure shows the mapping of prachConfigIndex to physical location of PRACH region. Table below outlines PrachConfigindex to RACH region mapping (FDD).


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Configuring PRACH Configuration Index (using the parameter PRACH_CONFIG_INDEX) implicitly configures the preamble format to be used. Also that RACH Optimization will not modify PRACH Configuration Index in such a way as to change the preamble format that was initially configured by the operator (that is, PRACH Config Index can be adapted within the scope of the configured preamble format (via the initially configured PRACH Configuration Index) eNB performs statistical analysis of RACH related OMs and optimizes RACH configuration based on performance. Figure below depicts an overview of optimization algorithm.

Whenever UE has succeed RACH access, eNB transmits UE Information Request message with rach-ReportReq = True to the UE. Then, UE transmits UE Information Response message including the number of preambles sent for successful RACH access (numberOfPreamblesSent) and the indicator whether the UE has experienced contention during RACH access (contentionDetected). Upon receiving the UE Information Response message, RO statistic management in eNB collects RACH related statistics on numberOfPreamblesSent and contentionDetected. At every RACH Optimization period, if the number of dedicated preambles is not changed, eNB optimizes Initial Received Target Power, Power Ramping Step, and PRACH Configuration Index as follows:

1 If Avg_Pre_Sent_Num_Increase is larger than PROB_POWER_INCREASE, eNB checks Det_Cont_Ratio_Increase.

aIf Det_Cont_Ratio_Increase is larger than PROB_CONTENTION_INCREASE, eNB inform EMS that random access opportunity should be increased. Then, EMS adjusts PRACH Configuration Index of the cell in a way to increase random access opportunity considering neighboring cells. [This is a scenario where UEs are not able to capture PRACH channel due to less opportunities, which is causing a lot of preamble collision.]


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bIf Det_Cont_Ratio_Increase is smaller than PROB_CONTENTION_INCREASE, eNB increases preambleInitialReceivedTargetPower by 1 step (the step size for this increase is 2 dBm) to make UEs to transmit preambles with higher Tx power. If preambleInitialReceivedTargetPower will be larger than preambleInitialReceivedTargetPower_max, power ramping step (indicated by the parameter POWER_RAMPING_STEP) is increased by 1 step (the step size for this increase is 2 dB) instead of preambleInitialReceivedTargetPower. [This is a scenario where UEs are not able to capture PRACH channel due to inadequate preamble power and thus take more retries.]

2 If Avg_Pre_Sent_Num_Decrease and Det_Cont_Ratio_Decrease are smaller than PROB_POWER_DECREASE and PROB_CONTENTION_DECREASE respectively, Random Access Opportunity/Power are lowered.

aeNB requests decrease of random access opportunity to EMS. Upon receiving the request, EMS adjusts PRACH Configuration Index in a way to decrease random access opportunity.

bPower ramping step is firstly decreased by 1 step if power ramping step reduced by 1 step is larger than POWER_RAMPING_STEP_MIN. Otherwise, preambleInitialReceivedTargetPower is reduced by 1 step. Backoff Indicator Adjustment for RACH optimization Backoff Indicator (BI) is an optional parameters used to adjust preamble retransmission timing whenever random access of UE is failed. Samsung implementation modifies the Backoff value only under the limited conditions of excessive contention and only if PRACH opportunity parameters cannot be modified any further. Value of BI is defined in 3GPP specification as following Table. Index

Backoff Parameter value (ms)

0

0

1

10

2

20

3

30

4

40

5

60

6

80

7

120

8

160

9

240

10

320

11

480

12

960

13

Reserved

14

Reserved

15

Reserved


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BI is utilized in Random Access as follows. If eNB transmits Random Access Response (RAR) message with BI = 3 (30 ms), all UEs receiving the RAR message select random time between 0 and 30 ms and delay preamble retransmission timing by the randomly selected time if they fail random access. When BI_OPT_ENABLE is set to 1 by operator (this will automatically reset the value of BACKOFF_INDICATOR to 0), eNB performs BI optimization according to the following procedures. These procedures are executed at RACH optimization period if the number of dedicated preambles is not changed in the RACH optimization period:

1 If Avg_Preamble_Sent_Num_Increase and Det_Cont_Ratio_Increase are larger than PROB_POWER_INCREASE and PROB_CONTENTION_INCREASE respectively, eNB determines whether current random access opportunity is currently reached to maximum or not.

aIf random access opportunity can be increased, eNB requests EMS to increase random access opportunity. Then, EMS adjusts PRACH Configuration Index to increase random access opportunity.

bIf random access opportunity cannot be increased because it already reached to maximum value, eNB increases BI by BI_SIZE.

cIn Step B if the Backoff indicator already reached the max allowed value (BI_Max) then the Backoff indicator is not changed.

2 If Avg_Preamble_Sent_Num_Decrease and Det_Cont_Ratio_Decrease are smaller than PROB_POWER_DECREASE and PROB_CONTENTION_DECREASE respectively, eNB determines whether current BI is 0 or not.

aIf BI is not 0, eNB reset BI to 0. bOtherwise, Random Access Opportunity or preamble transmission power related parameters are reduced.



The RACH optimization function is activated in the EMS. The UE supports RACH report functionality (that is, UE Information procedure).The X2 messages include PRACH Configuration information.

BACKOFF_INDICATOR_SETUP should be set to Setup for performing Backoff Indicator Optimization by running CHG-RACH-CONF. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Activation Procedure To activate this feature, do the following:

Run CHG-SONFN-CELL and set RACH_OPT_ENABLE to Auto or Manual to activate RACH optimization feature.

Run CHG-SONFN-CELL and set RSI_CONFLICT_ENABLE to Auto or Manual to activate RS conflict detection and RSI reallocation feature.

1 For RACH optimization, eNB requests RACH report information to UE that is connected to the serving (that is, Attach or Idle-to-Active cases) or target cell (for example, Handover case).

2 The eNB successfully performs UE Information procedure with UE and then controls related counters using received RACH report information.

3 For RS collision detection and RSI reallocation, eNB monitors the X2 Setup Request, X2 Setup Response, and X2 eNB Configuration Update messages.

4 The eNB checks if RS collision occurs using the received RACH configuration information.

5 If RS collision is detected, eNB reports RS conflict message to the EMS. 6 If new RSI is reallocated from the EMS, eNB adapts new RSI value to the system. Deactivation Procedure To deactivate this feature, do the following:

Run CHG-SONFN-CELL and set RACH_OPT_ENABLE to Off to deactivate RACH optimization feature.

Run CHG-SONFN-CELL and set BI_OPT_ENABLE to Off to deactivate Backoff Indicator optimization.

Run CHG-SONFN-CELL and set RSI_CONFLICT_ENABLE to Off to deactivate RS collision detection and RSI reallocation feature.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-CELL/RTRV-SONFN-CELL Parameter

Description

RACH_OPT_ENABLE

This parameter indicates whether to enable the Rach Optimized function (one of the SON functions). Off: The function is turned off. Manual: When the parameter value is changed by an algorithm, this change is applied after confirmation of operator. Auto: When the parameter value is changed by an algorithm, this change is


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Chapter 8 SON Parameter

Description applied automatically.

BI_OPT_ENABLE

The parameter is used to control the Backoff Indicator Optimization operation in two modes. Off: BI Optimization is disabled. On: BI Optimization is enabled.

RSI_CONFLICT_ENABLE

This parameter indicates whether to enable RootSequenceIndex (RSI) SON function (one of the SON functions). Off: The function is turned off. Manual: When RootSequenceIndex is conflicted in a certain cell, Conflict Detection and resolve is done after confirmation of operator. Auto: When RootSequenceIndex is conflicted in a certain cell, Conflict Detection is done automatically.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Table below outlines SON property for RSI auto-configuration in LSM. Parameter

Description

R Count

Number of Cell to use for calculating average of NRT, PCI, RSI.

RSI Type

Criteria of the effective radius when allocating RSI. Can set to minimum, average or distance. minimum: using R as distance with nearest neighbor cell. distance: criteria of fixed distance. average: use of R multiplied by RSI Multiple as effective radius where R is the distance obtained by averaging the inter-site distance with the neighbor cells in the nearest order (The number of neighbor cells is R Count).

RSI Multiple

Expansion range of calculating the effective distance when allocating RSI.

RSI Limit Distance

Minimum of the effective radius when allocating RSI.

Parameter Descriptions of CHG-SON-RO/RTRV-SON-RO Parameter

Description

T_PERIOD

The period of statistics monitoring. This value (1 Day/1 Week/1 Month, default = 1 Month) is used for triggering the RACH parameter control. one_day: RO is triggered based on handover statistics collected for 1 day. one_week: RO is triggered based on handover statistics collected for 1 week. one_month: RO is triggered based on handover statistics collected for 1 month.

T_PERIOD_TEMP

The period of fallback statistics monitoring. This value (1 Hour/1 Day/1 Week, default = 1 Week) is used for checking a fault where RACH performance is not temporarily met after the RACH parameter is changed. one_hour: Fallback for RO based on the handover statistics collected for 1 hour. one_day: Fallback for RO based on the handover statistics collected for 1 day. one_week: Fallback for RO based on the handover statistics collected for 1 week.


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Description

RACH_FILTERING_COEFF

The coefficient applied to filtering when processing RACH statistics data. F(n) = (1-rachFilteringCoeff)xF(n-1) + rachFilteringCoeff x CurrentValue

DEDICATED_INCREASE

The threshold that increases the number of dedicated preambles.

DEDICATED_DECREASE

The threshold that decreases the number of dedicated preambles.

PROB_DEDICATED_INCREA SE

The probability that increases the number of dedicated preambles.

PROB_DEDICATED_DECRE ASE

The probability that decreases the number of dedicated preambles.

DEDICATED_MAX

The maximum value of the number of dedicated preambles. {n0, n4, n8, n12, n16, n20, n24, n28, n32, n36, n40, n44, n48, n52, n56, n60}

DEDICATED_MIN

The minimum value of the number of dedicated preambles. {n0, n4, n8, n12, n16, n20, n24, n28, n32, n36, n40, n44, n48, n52, n56, n60}

POWER_INCREASE

The threshold that increases preamble Tx-related power resources.

POWER_DECREASE

The threshold that decreases preamble Tx-related power resources.

PROB_POWER_INCREASE

The probability that increases preamble Tx-related power resources.

PROB_POWER_DECREASE

The probability that decreases preamble Tx-related power resources.

PREAMBLE_INITIAL_RECEI VE_TARGET_POWER_MAX

The maximum value of initial received target power. {dBm-120, dBm-118, dBm-116, dBm-114, dBm-112, dBm-110, dBm-108, dBm-106, dBm-104, dBm-102, dBm-100, dBm-98, dBm-96, dBm-94, dBm92, dBm-90}

PREAMBLE_INITIAL_ RECEIVED_TARGET_POWE R_MIN

The minimum value of initial received target power. {dBm-120, dBm-118, dBm-116, dBm-114, dBm-112, dBm-110, dBm-108, dBm-106, dBm-104, dBm-102, dBm-100, dBm-98, dBm-96, dBm-94, dBm92, dBm-90}

POWER_RAMPING_STEP_M AX

The maximum value of ramping step. {dB0, dB2,dB4, dB6}

POWER_RAMPING_STEP_M IN

The minimum value of ramping step. {dB0, dB2,dB4, dB6}

CONTENTION_INCREASE

The threshold that increases PRACH configuration index.

CONTENTION_DECREASE

The threshold that decreases PRACH configuration index.

PROB_CONTENTION_INCR EASE

The probability that increases PRACH configuration index.

PROB_CONTENTION_DECR EASE

The probability that decreases PRACH configuration index.

TH_RSI_CONFLICT_REPOR T_ HOLD

This parameter represents the RSI conflict report holding time when an RSI conflict event was already issued. The eNB starts the RSI conflict report holding timer with this parameter value after a notify specific RSI conflict event to the LSM. While this timer is running, the same RSI conflict event will not be reported to the LSM. New RSI conflict reports are stored and a notification to the LSM will be sent after the RSI conflict report holding timer expires (unit: seconds).

TH_RSI_REALLOCATE_LAT ENCY

This parameter represents the waiting time for RSI reallocation request. The eNB receives an XCHG-RSI-TIMER command from the LSM and starts the RSI reallocation timer using this parameter value. The timer is stopped when the RSI reallocation accomplishes within the waiting time. However, if the RSI reallocation is not performed within the waiting time and the timer expires, then the eNB will send an RSI reallocation request message (SON RSI REALLOC TIMEOUT) to the LSM (unit: minutes).

BI_SIZE

Step size for BI increase. Its value means the number of index increased when BI optimization algorithm decides to increase BI.


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Description Ex) If BI_SIZE = 2, BI value is changed from 0ms (0) to 20ms (2), from 10ms (1) to 30ms (3), and so on.

BI_MAX

Maximum value of BI that can be adjusted by BI optimization.

Parameter Descriptions of CHG-PRACH-CONF/RTRV-PRACH-CONF Parameter

Description

PRACH_CONFIG_INDEX

Index for the preamble format, subframe sent by preamble, and interval.

ROOT_SEQUENCE_INDEX

The first logical root sequence index used to create a random preamble. Different values should be assigned to neighboring cells. Be cautious to change because it cause inter-cell interference among the cells with same physical root sequence. Please refer to the SON Algorithm for changing this parameter because it affects the entire system.

PRACH_POSITION

Provides information about PRACH position between two possible positions adjacent to PUCCH. 0: low position 1: high position

Parameter Descriptions of CHG-RACH-CONF/RTRV-RACH-CONF Parameter

Description

SIZE_OF_RA_PREAMBLES_ GROUP_A

This parameter is the number of preambles group A.

POWER_RAMPING_STEP

This parameter specifies the power ramping steps for preamble transmit power when preamble transmission counter increases.

PREAMBLE_INIT_RCV_TAR GET_POWER

This parameter specifies the initial target receiving power of preambles. Value dBm-120 correspond to-120 dBm and so on.

BACKOFF_INDICATOR_SET UP

This parameter setup or release the backoff indicator. Release: release. Setup: setup.

BACKOFF_INDICATOR

This parameter specifies the backoff value.


Type Name

Type Description

Random Access Preambles

DedicatedPreambles

The cumulated number of dedicated preambles among the periodically collected RACH preambles.

DedicatedPreamblesAssig nFail

The number of failures to get dedicated preamble allocation after requesting the dedicated preamble from the RRC to the MAC.

RandomlySelectedPreamb lesLow

The cumulated number of the preambles belonging to Group A among the detected contention based preambles.

RandomlySelectedPreamb lesHigh

The cumulated number of the preambles belonging to Group B among the detected contention based preambles.


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RACH Usage

Type Name

Type Description

RACHUsageAvg

The average of RACH usage rates that were collected during the collection interval.

HandoverDedicatedPream bles

The cumulated number of dedicated preambles due to Handover order among the periodically collected RACH preambles.

RandomAccessResponses

The cumulated number of RandomAccessResponse (RAR) messages are transmitted. For this counter, the statistics are collected periodically.

PreambleSent1

Count when the number of RACH preamble sent is 1.

PreambleSent2


Preamblesent3


Preamblesent4


Preamblesent5


Preamblesent6


Preamblesent7

Count when the number of RACH preamble sent is 7

Preamblesent8


Preamblesent9


RACHContention

Ratio of RACH contention occurrence.

RACHReportsRcvNum

Count when rachReport is received.

REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 9) [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 9) [3] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [4] 3GPP 32.500: E-UTRAN; Self-Organizing Networks (SON); Concepts and requirements [5] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; Concepts and requirements [6] 3GPP 32.521: E-UTRAN; Self-Organizing Networks (SON) Policy Network Resource Model (NRM) Integration Reference Point (IRP); Requirements [7] 3GPP 32.522: E-UTRAN; Self-Organizing Networks (SON) Policy Network Resource Model (NRM) Integration Reference Point (IRP); Information Service (IS) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[8] 3GPP 32.541: E-UTRAN; Self-Organizing Networks (SON); Self-healing concepts and requirements


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LTE-SO0501, Intra-LTE MRO INTRODUCTION Samsung MRO optimizes the HO performance automatically during system operation, in order to satisfy KPI for HO success rate and to reduce ping-pong. Samsung MRO is triggered at regular intervals, and controls HO parameters based on the HO statistics collected during the interval. The HO-related statistics used by Samsung MRO include all the HO-related problems specified in 3GPP standard (Too-late HO/Too-early HO/HO to Wrong Cell). RLF INDICATION messages and HANDOVER REPORT messages delivered through X2 interface are used to collect statistics on the above problems. For this operation, eNB saves the information about served cell of neighbor eNB which is included in X2 SETUP REQUEST/REPONSE and eNB CONFIGURATION UPDATE messages. The eNB uses this information to transmit RLF INDICATION and HANDOVER REPORT messages. Samsung MRO algorithm defines separate HO success rate for MRO by using HO and MRO statistics. Moreover it determines the followings:

whether it is needed to change HO parameters by using the HO success rate for MRO.

whether the HO related problem was resolved by CIO adjustment by MRO algorithm. The HO-related problems based on the Release 9 standard are collected through the RRC connection reestablishment request message transmitted to the target cell for re-establishment decided through cell search process when the UE fails the HO operation or experiences RLF within a short time during the HO operation or after the completion. After a UE experiences above-mentioned problem, the Release 10 standard provides a method that may collect the HO-related problems even at the failure in cell search or in the process of RRC connection reestablishment. In other words, if a UE fails in the operation of RRC connection re-establishment, the UE transits to the RRC_IDLE mode and performs the RRC connection setup operation to the cell detected through the cell search process. In this process, the UE reports information on RLF or HO failure related problem (rlf-report-r9) experienced just before RRC connection setup to the serving cell through UE information procedure. Then, the serving cell collects HO-related problem using this information or transmits RLF INDICATION message including rlf-report-r9 to RLF source cell of the UE in order to the source cell can collects the HO-related problem.


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Samsung MRO controls CIO, the HO parameter that changes HO time at the cell‟s level, in order to satisfy KPI on HO success rate and to reduce ping-pong HO. If the HO success rate per each neighbor cell measured when it reaches a point of the end of the cycle satisfies the KPI, Samsung MRO adjusts the CIO value to reduce the ping-pong HO. If the KPI is not satisfied, the function changes the CIO value based on the tendency of the HO-related problems. It also monitors if the HO or call drop rate performance sharply slows down for a certain period of time after changing the CIO value. If so, it performs fallback action to return to the previous CIO value, maintaining stability of HO performance. If A2 event is used to activate measurement gap for inter-frequency measurement, Samsung MRO adjusts A2 threshold which can change the point of measurement on inter-frequency neighbor cell. This function is designed for the inter-frequency neighbor cell, i.e. the neighbor cell whose information on the frequency is the different from the information on the frequency for the serving cell. MRO algorithm controls the A2 threshold according to the result of CIO change after adjusting CIO value of each neighbor cell when it reaches the end of the cycle. It also monitors if the HO or call drop rate performance sharply slows down for a certain period of time after changing the A2 threshold value. If so, it performs fallback action to return to the previous A2 threshold value, maintaining stability of HO performance.

BENEFIT CAPEX and OPEX expenses used to enhance HO performance during the system operation can be reduced.

As the optimized HO is performed in consideration of coverage and air status of each neighbor cell, it provides great user experience through maximum performance with high HO success rate and low call drop rate. eNB uses the RSRP/RSRQ of serving cell and best neighbor cell. The information is reported by UE and shared between eNBs via X2. If there is no neighbor cell that has stronger signal strength than the source cell, the algorithm decides that there is a coverage hole between two cells.


Interface & Protocols To activate the MRO function, X2 interface must be established with neighbor eNBs.

Prerequisite Features LTE-SW0521, X2 Interface Management

Others


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HO-related problems based on the Release 10 standard may be collectible only when the UE supports a function of including r10-related information to the rlf-report-r9 information.

LIMITATION None

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Interdependencies between Features Interdependent Feature: LTE-SO0201, Intra-LTE ANR Intra-LTE ANR feature optimizes NRT (Neighbor Relation Table) by automatically adding new neighbor cells based on UE (User Equipment) measurement reports and deleting neighbor cells based on handover statistics. Performance and Capacity Intra-LTE MRO automatically detects handover problem for each neighbor cell and resolves it by changing handover parameters. This guarantees reliable mobility of the UEs when the UEs are moving between cells. Interfaces To collect handover problems between the cells in different eNBs, eNBs exchange X2 messages such as RLF Indication and Handover Report.

FEATURE DESCRIPTION Architecture The Samsung MRO function works in eNB. Figure below depicts the overall architecture of the function.


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In the above architecture, the Samsung MRO function is performed by the SON agent of eNB and the block operates for each eNB. The detailed procedures are as follows:

SON Agent: HO-related problem detection function aReceives the RLF INDICATION/HANDOVER REPORT message from X2. bReceives UE context from RRC. cCollects and delivers the statistics on the causes of HO-related problems to OAM.

SON Agent: HO parameter control triggering function aMonitors the MRO algorithm action interval. bMonitors change in HO or call drop rate performance for certain period of time after change of CIO and A2 threshold.

cCollects statistics on HO and HO-related problems from OAM. dDetermines whether to change HO parameters. eTriggers HO parameter control action and delivers the MRO algorithm input. SON Agent: HO parameter control function aControls HO parameters to reduce Ping-pong HO. bControls HO parameters based on the HO-related problems. cProvides the changed CIO and A2 threshold to OAM.


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MRO Function Collection of Handover-related Problem Statistics Collection of HO-related problem statistics based on 3GPP Release 9 specification In the Samsung MRO function, HO-related problems based on the Release 9 standard are subdivided and collected as follows: Time that RLF Occurs

Re-establishment Cell Serving Cell

Target Cell

Other Cell

Before HO Initiation

(1) CoverageHole

N/A

(2) TooLateHO (RLFBeforeTriggering)

After HO Triggering

(3) CoverageHoleN

(4) TooLateHO (RLFAfterTriggering)

(6) HOtoWrongCell (RLFAfterTriggering)

During HO Execution

(7) TooEarlyHO (HOFailure)

(5) CoverageHoleN (4) TooLateHO (RLFAfterTriggering)


(5) CoverageHoleN After HO Execution

(8) TooEarlyHO (RLFAfterHO)

(9) CoverageHoleN

(10) HOtoWrongCell (RLFAfterHO)

The details of statistics items mentioned in the above table are as follows:

1 CoverageHole aRLF occurs without any HO initiation in UE. bUE requests for RRC Connection Reestablishment to the serving cell. cIf there is an RLF report and the coverage hole conditions are satisfied, the serving cell collects the statistics of CoverageHole.

dIf there is an RLF report and the coverage hole conditions are not satisfied, the serving cell does not collect the statistics of CoverageHole.

eIf there is no RLF report, the serving cell collects the statistics of CoverageHole.

2 TooLateHORLFBeforeTriggering aRLF occurs without any HO initiation in UE. bUE requests for RRC Connection Reestablishment to the other cell. cThe cell transmits the RLF INDICATION message to the serving cell through the X2 interface.

dThe serving cell collects the statistics with other cells. 3 CoverageHoleN aUE transmits the MR message initiated by triggering HO. bUE requests for RRC Connection Reestablishment to the serving cell.


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cIf there is an RLF report and the coverage hole conditions are satisfied, the serving cell collects the statistics of CoverageHoleN with another cell.

dIf there is an RLF report and the coverage hole conditions are not satisfied, the serving cell does not collect the statistics of CoverageHoleN with another cell.

eIf there is no RLF report, the serving cell collects the statistics of CoverageHoleN with another cell.

4 TooLateHORLFAfterTriggering aUE transmits the MR message initiated by triggering HO. bUE fails to receive a HO Command message from the service cell, or fails to perform HO with the target cell after receiving a HO command message.

cUE requests for RRC Connection Reestablishment to the target cell. dUE informs the target cell if it retains information on RLF report during RRC connection re-establishment procedure with the target cell. (If the UE retains information on the RLF report, RLF report is provided through the UE Information procedure.)

eThe target cell transmits the RLF INDICATION message to the serving cell through the X2 interface. (This message contains the RLF report if it is acquired.)

fIf there is an RLF report and the coverage hole conditions are not satisfied, the serving cell collects the statistics of TooLateHORLFAfterTriggering with the target cell.

gIf there is no RLF report, the serving cell collects the statistics of TooLateHORLFAfterTriggering with the target cell.

5 CoverageHoleN aUE transmits the MR message initiated by triggering HO. bUE fails to receive a HO Command message from the service cell, or fails to perform HO with the target cell after receiving a HO Command message.

cUE requests for RRC Connection Reestablishment to the target cell. dUE informs the target cell if it retains information on RLF report during RRC connection re-establishment procedure with the target cell. (If the UE retains information on the RLF report, RLF report is provided through the UE Information procedure.)

eThe target cell transmits the RLF INDICATION message to the serving cell through the X2 interface. (This message contains the RLF report if it is acquired.)

fIf there is an RLF report and the coverage hole conditions are satisfied, the serving cell collects the statistics of CoverageHoleN with the target cell.

6 HOtoWrongCellRLFAfterTriggering aUE transmits the MR message initiated by triggering HO.


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bUE fails to receive a HO Command message from the service cell, or fails to perform HO with the target cell after receiving a HO Command message.

cUE requests for RRC Connection Reestablishment to the other cell, not to the serving cell or the target cell.

dThe other cell transmits the RLF Indication message to the serving cell through the X2 interface.

eThe serving cell collects the statistics with the target cell. 7 TooEarlyHOHOFailure aUE transmits the MR message initiated by triggering HO. bUE receives the HO Command message from the serving cell. cUE fails HO with the target cell. dUE requests for RRC Connection Reestablishment to the serving cell. eThe serving cell collects the statistics with the target cell. 8 TooEarlyHORLFAfterHO aUE transmits the MR message initiated by triggering HO. bUE receives the HO Command message from the serving cell. cUE successfully performs the HO with the target cell. dUE creates RLF in a short period of time (Tstore_ue_cntxt). eUE requests for RRC Connection Reestablishment to the previous serving cell.

fThe serving cell transmits the RLF INDICATION message to the target cell through the X2 interface.

gThe target cell transmits the HANDOVER REPORT message to the serving cell through the X2 interface.

hThe serving cell collects the statistics with the target cell. 9 CoverageHoleN aThe UE transmits the MR message by HO triggering bThe UE receives the HO Command message from the serving cell. cThe UE successfully performs the HO with the target cell. dThe UE generates RLF in a short period of time (Tstore_ue_cntxt). eThe UE requests for RRC connection reestablishment to the existing target cell.

fIf there is an RLF report and the coverage hole conditions are satisfied, the target cell collects the statistics of CoverageHoleN with the serving cell.

gIf there is an RLF report and the coverage hole conditions are not satisfied, the target cell does not collect the statistics of CoverageHoleN.

hIf there is no RLF report, the target cell collects the statistics of CoverageHoleN with the serving cell. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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10 HOtoWrongCellRLFAfterHO aUE transmits the MR message initiated by triggering HO. bUE receives the HO Command message from the serving cell. cUE successfully performs the HO with the target cell. dUE creates RLF in a short period of time (Tstore_ue_cntxt). eUE requests for RRC Connection Reestablishment to the other cell, not to the serving cell or the target cell.

fThe other cell transmits the RLF INDICATION message to the target cell through the X2 interface.

gThe target cell transmits the HANDOVER REPORT message to the serving cell through the X2 interface.

hThe serving cell collects the statistics with the target cell. Collection of HO-related problem statistics based on 3GPP Release 10 specification The HO-related problems based on the Release 10 in Samsung MRO function are collected by using the rlf-report-r9 information acquired through the UE information procedure after the completion of the RRC connection establishment procedure of the UE. If the UE experiences RLF or fails the HO operation, it logs the event. If the UE fails in reestablishing RRC connection, it re-performs the process of RRC connection establishment to the cell detected by the cell search process after transition to the RRC_IDLE mode. If the UE sets rlf-InfoAvailabler10 as true in the RRC connection setup complete message during the process, the serving cell performs the UE information procedure to obtain the rlf-report-r9 information of the UE. The r10-related information added to the existing rlfreport-r9 in the Release 10 standard is as follows:

1 failedPCellId-r10 aIf the UE goes through the RLF: ECGI of the serving cell connected at the time of the generation of the RLF (cellGlobalId-r10)

bIf the UE fails the HO operation: pci-arfcn-r10 of the HO target cell (Information on PCI (physCellId-r10) and frequency (carrierFreq-r10))

2 reestablishmentCellId-r10:ECGI of the cell that transmits the RRC connection reestablishment request message after the cell search process and after the UE experiences RLF or fails the HO operation

3 timeConnFailure-r10 aIf the UE goes through the RLF: The period from the time of receiving the latest HO Command message to the RLF occurrence time.

bIf the UE fails the HO operation: The period from the time of receiving the latest HO Command message to the time of failing the HO operation

4 connectionFailureType-r10 aIf the UE goes through the RLF: „rlf‟ bIf the UE fails the HO operation: „hof‟ eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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5 previousPCellId-r10: ECGI of the cell that sent the latest HO Command message. In Samsung MRO function, the cell with which UE establishes RRC connection collects the information of the HO-related problem by itself, if failedPCellId-r10 in the rlf-report-r9 information matches its own PCI. This reduces the X2 messaging overhead for collecting information of the HOrelated problem. If failedPCellId-r10 is different from its own PCI, it transmits the RLF INDICATION message to the cell which served UE before RLF by type of connection failure. In Samsung MRO function, statistics are collected only if the RRC connection setup cell and the reestablishment cell are identical to determine the HO-related problem based on Release 10. If one of following conditions is satisfied, Samsung MRO function considers that RRC connection setup cell and the reestablishment cell are identical:

6 If the reestablishmentCellId-r10 value exists in rlf-report-r9 and it is identical to the ECGI of the RRC connection setup cell.

7 If there is no reestablishmentCellId-r10 value in rlf-report-r9 and the best neighbor cell based on the signal strength is the RRC connection setup cell. The best neighbor cell refers to the highest upper cell of measResultNeighCells in rlf-report-r9 (Refer to Section 2.2.1.1) In Samsung MRO function, the HO-related problems based on the Release 10 standard are subdivided and collected as follows: The following table is HO-related problem classification based on 3GPP Release 10 spec: Time that RLF Occurs

RRC Connection Setup Cell Serving Cell

Target Cell

Other Cell

Before HO initiation & After HO triggering

(1) CoverageHole

N/A

(2) TooLateHO (RLFBeforeTriggering)

During HO execution

(3) TooEarlyHO (HOFailure)

(4) CoverageHoleN


After HO execution

(6) TooEarlyHO (RLFAfterHO)

(7) CoverageHoleN

(8) HOtoWrongCell (RLFAfterHO)

The collection status of each item referred to in the above table is as follows:

1 CoverageHole aThe UrE is connected for the Tstore_ue_cntxt time or more in the existing serving cell.

bThe UE experiences the RLF before HO initiation. cThe UE fails the RRC Connection Reestablishment operation. dThe UE succeeds the RRC Connection Setup process. eIt is checked that the newly connected cell is the existing serving cell of the UE by using the rlf-report-r9 information acquired from the UE.


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fThe newly connected cell collects the statistics by using the rlf-report-r9 information.

2 TooLateHORLFBeforeTriggering aThe UE is connected for the Tstore_ue_cntxt time or more in the existing serving cell.

bThe UE experiences the RLF before HO initiation. cThe UE fails the RRC Connection Reestablishment operation. dThe UE succeeds the RRC Connection Setup process. eEnsure that the newly connected cell is a cell other than the existing serving cell of the UE by using the rlf-report-r9 information acquired from the UE and transmit the RLF INDICATION message to the existing serving cell (RLF source cell).

fThe existing serving cell collects the statistics for the other cell by using the rlf-report-r9 information.

3 TooEarlyHOHOFailure aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE fails HO to the target cell. dThe UE fails the RRC Connection Reestablishment operation. eThe UE succeeds the RRC Connection Setup procedure. fIt is checked that the newly connected cell is the existing serving cell of the UE by using the rlf-report-r9 information acquired from the UE.

gThe newly connected cell collects the statistics for the HO target cell by using the rlf-report-r9 information.

4 CoverageHoleN aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE fails HO to the target cell. dThe UE fails the RRC Connection Reestablishment operation. eThe UE succeeds the RRC Connection Setup process. fIt is checked that the newly connected cell is the HO target cell of the UE by using the rlf-report-r9 information acquired from the UE.

gThe newly connected cell collects the statistics for the existing serving cell by using the rlf-report-r9 information.

5 HOtoWrongCellRLFAfterTriggering aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE fails HO to the target cell. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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dThe UE fails the RRC Connection Reestablishment operation. eThe UE succeeds the RRC Connection Setup process. fEnsure that the newly connected cell is a cell other than the existing serving cell and HO target cell of the UE by using the rlf-report-r9 information acquired from the UE and transmit the RLF INDICATION message to the existing serving cell (RLF source cell).

gThe existing serving cell collects the statistics for the HO target cell by using the rlf-report-r9 information.

6 TooEarlyHORLFAfterHO aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE succeeds HO to the target cell. dThe UE experiences RLF in a short period of time (Tstore_ue_cntxt). eThe UE fails the RRC Connection Reestablishment operation. fThe UE succeeds the RRC Connection Setup process. gIt is checked that the newly connected cell is the existing serving cell of the UE by using the rlf-report-r9 information acquired from the UE.

hThe newly connected cell collects the statistics for the HO target cell by using the rlf-report-r9 information.

7 CoverageHoleN aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE succeeds HO to the target cell. dThe UE experiences RLF in a short period of time (Tstore_ue_cntxt). eThe UE fails the RRC Connection Reestablishment operation. fThe UE succeeds the RRC Connection Setup process. gIt is checked that the newly connected cell is the HO target cell of the UE by using the rlf-report-r9 information acquired from the UE.

hThe newly connected cell collects the statistics for the existing serving cell by using the rlf-report-r9 information.

8 HOtoWrongCellRLFAfterHO aThe UE transmits the MR message by HO triggering. bThe UE receives the HO Command message from the serving cell. cThe UE succeeds HO to the target cell. dThe UE experiences RLF in a short period of time (Tstore_ue_cntxt). eThe UE fails the RRC Connection Reestablishment operation. fThe UE succeeds the RRC Connection Setup process. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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gEnsure that the newly connected cell is a cell other than the existing serving cell and HO target cell of the UE by using the rlf-report-r9 information acquired from the UE and transmit the RLF INDICATION message to the existing serving cell (RLF source cell).

hThe existing serving cell collects the statistics for the HO target cell by using the rlf-report-r9 information. Detection of Ping-pong Handover The Ping-pong HO means a problem of HO being generated from one cell to the other and then returning to the original cell again within a short time. In this case, because the HO to the other cell causes the waste of network resources due to unnecessary operations, such HO generation must be minimized. To detect the occurrence of the ping-pong HO generation, before HO to the cell, the HO target cell uses the Last Visited E-UTRAN Cell Information IE including (1) the cell information visited before and (2) the information on the time of staying in the cell. The IE is included in the UE History Information IE of the X2 HANDOVER REQUEST/S1 HANDOVER REQUIRED messages for HO preparation. The procedure of the HO target cell for collecting the ping-pong HO statistics is as follows:

1 Acquire the Last Visited E-UTRAN Cell Information IE for the UE. 2 The HO target cell searches the latest visited records in the Last Visited EUTRAN Cell Information IE when the UE completes the RRC connection. oTime of receiving the RRC connection reconfiguration complete message from the HO-in UE. oTime of receiving the RRC connection reestablishment complete message from the HO-in UE

3 If the cell finds itself, and the sum of the Time UE stayed in Cell IE as the time of staying the cells visited (Cell1, …, Celln) just before itself is satisfied, the HO target cell collects the ping-pong HO statistics for the Cell1.



n

i 1

TimeStayCe ll i  PINGPONG _ HANDOVER _ TIMER

oPINGPONG_HANDOVER_TIMER: The base time value to detect the occurrence of the ping-pong HO (Unit: second, Setting command: CHGSON-MRO). Detection of Coverage Hole The Samsung MRO function detects and compiles statistics on coverage holes based on the RLF report included in the RLF indication message. In the Samsung MRO function, the target cell acquires RLF report information from UE through the following procedures:

1 UE transmits the MR message initiated by triggering HO. 2 UE fails to receive a HO command from the service cell, or fails to perform HO with the target cell after receiving a HO command.

3 UE requests for RRC connection reestablishment to the target cell. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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4 If RLF report information is included in the RRC connection reestablishment complete message, UE sets the rlf-InfoAvailable-r9 IE value in this message to True.

5 The target cell sets the rlf-ReportReq IE value in the UE information request message to True.

6 UE includes the RLF report information (RLF-Report-r9) in the UE information response message. Out of the RLF report information transmitted by UE, measResultLastServCell contains the serving cell measurement results before RLF, and measResultNeighCells contains the measurement results of the neighbor cells before RLF. The cell that makes the highest result is placed at the top, and other cells are lined up in the descending order. If MeasConfig contains MeasObjectEUTRA of different EUTRA frequencies, MeasResultList2EUTRA contains carrier frequency information and the corresponding MeasResultListEUTRA information. The Samsung MRO function decides the occurrence of coverage hole in the method shown below depending on available information including RSRP of the serving cell (RSRP_{ServingCell}), RSRQ of the serving cell (RSRQ_{ServingCell}), and RSRP of the best neighbor cell (RSRP_{BestNeighborCell}) in the RLF report information transmitted by the target cell. [Case1] If the information on RSRP and RSRQ of the serving cell and the RSRP of the best neighbor cell is collected, deciding the occurrence of coverage hole as follows:

aCalculate SINR (SINR_{ServingCell}) based on the serving cell by using the collected information.

bCalculate SINR (SINR_{BestNeighborCell}) based on the best neighbor cell by using the collected information.

cSINR = MAX (SINR_{ServingCell}, SINR_{BestNeighborCell}) dIf SINR < Threshold_{CoverageHole}, decide as coverage hole. [Case2] If the information on RSRP and RSRQ of the serving cell is collected, deciding the occurrence of coverage hole as follows:

aCalculate SINR (SINR_{ServingCell}) based on the serving cell by using the collected information.

bIf SINR_{ServingCell} < Threshold_{CoverageHole}, decide as coverage hole. [Case3] If the information on RSRP of the serving cell and RSRP of the best neighbor cell is collected, deciding the occurrence of coverage hole as follows: oIf RSRP_{BestNeighborCell}-RSRP_{ServingCell ]< 0, decide as coverage hole.


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In event of [Case1] and [Case2], if the coverage hole conditions are satisfied, the RF status in the RLF occurring area is considered poor and then it is decided as the RLF occurrence by the coverage hole. In event of [Case3], if the coverage hole conditions are satisfied, it means that there is no neighbor cell with the RSRP better than the RSRP of the serving cell in the RLF occurring area and therefore, it is decided as the RLF occurrence by the coverage hole. Figure below depicts the situation where the Samsung MRO function detects coverage hole.

Control of Handover Parameter The Samsung MRO algorithm is performed in the following procedures, and expressed as illustrated in Figure 3:

1 At the end of MRO algorithm period (T_PERIOD), if the number of HO attempts (number of HO preparation successes + number of TooLateHoRlfBeforeTriggering) for a neighbor cell is larger than the threshold (N_HANDOVER_THRESH), eNB controls CIO of the neighbor cell as follows. If the number of HO attempts for a neighbor cell is less than N_HANDOVER_THRESH, eNB counts HO attempts of the neighbor cell without initializing the number of HO attempts.

aIf HO success rate by neighbor cell ≥ HANDOVER_SUCCESS_KPI, the Samsung MRO function raises HO margin by adjusting the CIO value in order to decrease ping-pong HO.

bIf HO success rate measurement < HANDOVER_SUCCESS_KPI, iand if Too-late HO problem occurrence rate > Too-early HO problem occurrence rate and Too-late HO problem occurrence rate > HO-towrong-cell problem occurrence rate, the function reduces the HO margin by extending the CIO value in order to advance the HO point; iiand if Too-late HO problem occurrence rate < Too-early HO problem occurrence rate or Too-late HO problem occurrence rate < HO-towrong-cell problem occurrence rate, the function raises HO margin by reducing the CIO value in order to put off the HO point; iiiIf the rates of generating all HO-related problems are identical, keep the CIO value.

2 eNB controls A2 threshold according to the result of CIO change after controlling CIO of all neighbor cells. Detail operation is as follows. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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aeNB increases A2 threshold if increasing CIO did not improve the KPI of HO success rate for inter-frequency HO.

beNB decreases A2 threshold if “HO success rate per each inter-frequency neighbor cell ≥ HANDOVER_SUCCESS_KPI” and “there is no change in CIO of each inter-frequency neighbor cell.

3 If the HO or call drop rate performance is deteriorated after a certain period of time after the changed CIO and A2 threshold is applied, the function performs fallback action to return to the previous CIO and A2 threshold values for maintaining stability of HO performance. The following figure shows handover parameter control algorithm.

LSM Load Distribution Method by the MRO Function The CIO controlled by the Samsung MRO algorithm as a system parameter consists of the attributes of the NRT management object (ExternalEutranCellFDDLogic). Accordingly, if the CIO value per neighbor cell in the NRT of each cell is changed by the MRO function, the NRT update notification message is transmitted to the EMS for synchronizing the NRT management object synchronization with the EMS. The Samsung MRO function provides the following LSM load distribution method, because the instantaneous load to the LSM may occur if all cells connected to the EMS perform MRO function at the identical time.

1 All eNBs connected to the EMS perform the MRO function during the time from 00:00 to 03:00. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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2 Each eNB decides the time of performing its MRO function by using its eNBID oTime of performing the MRO function of eNB i: T_{MRO}(i)

3 Each eNB performs in the order of the served cell index at the time of performing its MRO function determined in Procedure (2). HO Parameter Optimization Abnormality Reporting Function At the situation where the CIO value by the MRO function operated in the eNB must be changed, if the changing operation fails, the eNB transmits the event of informing the failure to the LSM.


How to Activate This section provides the information that you need to configure the feature. Preconditions X2 RLF Indication and Handover Report messages are supported Activation Procedure To activate this feature, do the following:

Run CHG-SONFN-CELL and set MOBILITY_ROBUSTNESS_ENABLE to Auto to activate basic Intra-LTE MRO. oThe eNB analyses which handover problem (for example, Too Early HO, Too Late HO, HO to Wrong Cell, Ping-pong HO) is occurred based on Samsung MRO handover problem detection algorithm. oIf handover problem is detected, the eNB increases related counter by one. Every MRO period, the eNB performs Intra-LTE MRO statistics data analysis and determines whether or not to change handover parameters for solving handover problems. In the result of Inter-RAT MRO execution algorithm at every MRO period, IND_OFFSET (that is, Cell Individual Offset) parameter value of neighbour cell may be adjusted automatically.

Run CHG-SON-MRO and set INTER_FREQ_CONTROL to True to activate Intra-LTE Inter-frequency MRO. Deactivation Procedure To deactivate this feature, do the following:

Run CHG-SONFN-CELL and set MOBILITY_ROBUSTNESS_ENABLE to Off to deactivate basic Intra-LTE MRO.


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Run CHG-SON-MRO and set INTER_FREQ_CONTROL to False to deactivate Intra-LTE Inter-frequency MRO.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-CELL/RTRV-SONFN-CELL Parameters

Description

MOBILITY_ROBUSTNESS_ ENABLE

Whether to enable the CCO (coverage and capacity optimization) SON function, (one of the SON functions). Off: The function is turned off. Auto: When the parameter value is changed by an algorithm, this change is applied automatically.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SON-MRO/RTRV-SON-MRO Parameter

Description

T_PERIOD

The parameter indicates the operation period for the Mobility Robustness Optimization (MRO) function. The MRO algorithm is performed based on the handover and RLF (Radio Link Failure) statistics collected during this parameter value. one_day: MRO function is triggered based on the statistics collected for 1 day. one_week: MRO function is triggered based on the statistics collected for 1 week.

T_PERIOD_TEMP

The parameter indicates the value of the timer which monitors the following situation occurs: the performance of either HO or call drop rate during this parameter value is degraded when compared with that during the previous period. one_hour: The statistics is collected for 1 hour to monitor the fallback situation. one_day: The statistics is collected for 1 day to monitor the fallback situation.

HANDOVER_SUCCESS_K PI

The parameter indicates the threshold for Handover (HO) success Key Performance Indicator (KPI) to trigger the MRO algorithm (unit: %). The MRO algorithm is triggered if the HO success rate is lower than this parameter value.

N_HANDOVER_THRESH

The parameter indicates the threshold for the Handover (HO) attempt count to trigger the MRO algorithm. The MRO algorithm is triggered if the HO attempt count collected during the period (T_PERIOD) is higher than this parameter value.

OFFSET_MAX

The maximum value allowable for the Handover (HO) margin when Event A3 is used to the HO triggering condition in E-UTRAN system (Unit: dB). The HO margin in Event A3 is equal to as follows: HO margin = ofs - ofn + ocs - ocn + hys + off and the Cell Individual Offset (CIO) parameter controlled by the MRO algorithm indicates ocn. The value of CIO is optimized as satisfying the


714


Description condition that HO margin is equal to or less than this parameter value.

OFFSET_MIN

The minimum value allowable for Handover (HO) margin when Event A3 is used to the HO triggering condition in E-UTRAN system (unit: dB). The HO margin in Event A3 is equal to as follows: HO margin = ofs - ofn + ocs - ocn + hys + off and the Cell Individual Offset (CIO) parameter controlled by the MRO algorithm indicates ocn. The value of CIO is optimized as satisfying the condition that HO margin is equal to or greater than this parameter value.

PINGPONG_CONTROL

This parameter is the flag controlling whether the operation of ping-pong Handover (HO) reduction is performed or not. False: The operation of ping-pong HO reduction is not performed. True: The operation of ping-pong HO reduction is performed.

PINGPONG_HANDOVER_T IMER

The parameter indicates the threshold of time to detect the occurrence of the ping-pong Handover (HO) (unit: second).

TH_CALL_DROP_RATE

The parameter indicates the threshold for the call drop rate used to the follback condition after decreasing the Cell Individual Offset (CIO) value for reducing ping-pong Handover (HO) occurrence (unit: %).

INTER_FREQ_CONTROL

This parameter is the flag controlling whether the MRO (Mobility Robustness Optimization) function for inter-frequency neighbor cell is performed or not. False: The MRO function is not performed for inter-frequency neighbor cell. True: The MRO function is performed for inter-frequency neighbor cell.


Type Name

Type Description

MRO RLF Classification

CoverageHole

Number of RLF/HO failures due to the coverage hole.

CoverageHoleN

Number of RLF/HO failures due to the coverage hole toward Cell N.

TooEarlyHoFailure

The number of too-early handovers after transmitting the handover command.

TooEarlyHoRlfAfterHo

The number of too-early handovers after completing the handover process.

TooLateHoRlfBeforeTrigg ering

The number of RLFs before triggering the handover.

TooLateHoRlfAfterTriggeri ng

The number of RLFs after the handover command is transmitted.

WrongCellRlfAfterTriggeri ng

The number of handovers to a wrong cell before transmitting the handover command.

WrongCellRlfAfterHo

The number of handovers to a wrong cell after transmitting the handover command.

PingpongHandover

The number of ping-pong handovers detected by the ping-pong detection algorithm.

TooEarlyHoFailureVoice

The number of Too Early HO after transmitting the HO command of voice call.

TooEarlyHoRlfAfterHoVoic e

The number of Too Early HO after completing the HO procedure of voice call.

TooLateHoRlfBeforeTrigg eringVoice

The number of Too Late RLF before the HO Triggering of voice call.

MRO RLF VOICE Classification


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Intra-eNB Handover

X2 Out Handover

Type Name

Type Description

TooLateHoRlfAfterTriggeri ngVoice

The number of Too Late RLF after the HO Triggering of voice call.

WrongCellRlfAfterTriggeri ngVoice

The number of HO to a wrong cell after the HO Triggering of voice call.

WrongCellRlfAfterHoVoice

The number of HO to a wrong cell after transmitting the HO command of voice call.

PingpongHandoverVoice

The number of ping-pong HO occurrence which is detected by Ping-pong detection algorithm of voice call.

CoverageHoleAtSetup

Occurrence in radio link failure by a coverage hole in a serving cell RRC reestablishment in the serving cell.

CoverageHoleAtSetupN

RRC reestablishment in the target cell during or after handover.

TooEarlyHoFailureAtSetup

RRC reestablishment in the source cell without the terminal moving to the target cell due to the attempt for too-early handover.

TooEarlyHoRlfAfterHOAtS etup

Occurrence in radio link failure after the terminal moves to the target cell due to the attempt for too-early handover RRC reestablishment in the source cell.

TooLateHoRlfBeforeTrigg eringAtSetup

Occurrence in radio link failure in the serving cell by failing to attempt the handover even though the terminal has moved to another cell RRC reestablishment in the serving cell.

HoToWrongCellRlfAfterTri ggeringAtSetup

RRC reestablishment by the terminal in other cell while the handover procedure is not complete by attempting at the handover to the cell where the terminal is not located.

HoToWrongCellRlfAfterH OAtSetup

Occurrence in radio link failure in the target cell after completion of handover by attempting at the handover to the target cell RRC reestablishment in other cell by the terminal.

IntraEnbPrepSucc

The cumulated number when the RRC connection reconfiguration message is transmitted to the UE since preparation is completed for handover to the target cell between the inner blocks when intra HO is judged in the handover decision after a measurement report message is received from the UE.

IntraEnbSucc

The cumulated number when the target cell normally receives the RRC connection reconfiguration complete message from the UE by performing intra HO.

InterX2OutPrepSucc

The cumulated number when a RRC Connection Reconfiguration message is transmitted to the UE since a HandoverRequestAcknowledge message is received from the target eNB after a HandoverRequest message is transmitted to the target eNB due to inter X2 HO being judged in the HO decision after a MeasurementReport message is received from the UE.

InterX2OutSucc

The cumulated number when an UE context release command is normally received by the


716


Type Name

Type Description source eNB when the target eNB receives a RRC connection reconfiguration complete message from the UE after the source eNB transmits a RRCConnectionReconfiguration message to the UE through inter X2 HO execution.

Table below outlines the main Key Performance Indicators (KPIs) associated with this feature. Family Display Name

Type Name

Type Description

Mobility

EutranMobilityHoIntra

The calculated HOIntra success rate of E-UTRAN mobility.

EutranMobilityHOX2 Out

The calculated HOX2Out success rate of E-UTRAN mobility.

REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 10). [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 10). [3] 3GPP 36.423: E-UTRAN; X2 application protocol (X2AP) (Release 10). [4] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions. [5] 3GPP 32.500: E-UTRAN; Concepts & Requirements. [6] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases.


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LTE-SO0601, Sleeping Cell Detection INTRODUCTION The sleeping cell detection feature automatically detects sleeping cells to facilitate early detection of the absence of normal processing without alarm notices by eNB.

BENEFIT Using this feature, eNB's in abnormal conditions can be detected for efficient management.


FEATURE DESCRIPTION Sleeping Cell Detection Operation Sleeping cell detection operates in the following order, and if the sleeping cell condition is met, an alarm is generated and notified to the operator.

1 The number of normal CRRs is counted at every 15 minutes (0 min, 15 min, 30 min, and 45 min) from the top of hour to perform detection.

2 When the detection time arrives, it will check whether the number of normal Call Release Reasons (CRRs) for the recent 15 minutes for all cells that meet the detection condition is below the threshold.

3 If the number of normal CRRs is below the threshold, it is checked whether the number of CRR for past specific hours is below based on the time setting for the time window to which the current detection time belongs.

4 If the number of normal CRR for a specific past period of time is below the threshold, a silent alarm is generated.

5 The operator can set a specific past period of time. 6 If the number of normal CRR exceeds the threshold, and a silent alarm is generated to the cell, then a silent alarm is removed.

7 When an alarm is generated, the cell ID is displayed in the alarm position. 8 The operator can set the ON/OFF and threshold values of the silent alarm node detection feature for each Pico eNB and change them in the EMS client GUI. It can be set as follows.


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Chapter 8 SON Field

Description

Remark (Example)

eNB ID

eNB ID

1

Name

eNB Name

Roppongi

Cell

Specify whether to perform silent alarm detection.

ON: Perform alarm detection on the cell. OFF: Do not perform alarm detection on the cell.

Threshold

Threshold used to determine whether a silent alarm is generated.

0

PERI OD_1 ST

Range (unit: 15 min)

Duration for checking whether the cell is sleeping cell or not. If it is zero, PERIOD_1ST is deactivated (PERIOD_ALL value).

8

Start Hour

Start time of Period 1.

0

End Hour

End time of Period 1.

4


Duration for checking whether the cell is sleeping cell or not. If it is zero, PERIOD_2ND is deactivated (PERIOD_ALL value).

1

Start Hour

Start time of Period 2.

12

End Hour

End time of Period 2.

17


The CRR checking period for alarm detection when the detection time is not in Period 1 or 2.

2

PERI OD_2 ND

PERI OD_A LL

9 By designating cells to be excluded from detection, misjudgement on increasing traffic caused by events such as concerts can be prevented.

Condition to Exclude From Detection Detection is not performed in the following cases.

When the cell condition is locked If the CRR in 15 min statistics is NG (Not Good) or if the CRR statistics does not exist in Database

In case of the time of detection and the previous detection works are not yet finished

In case of eNB to which alarms are issued In case of eNB in which the sleeping cell feature is turned off. Sleeping Alarm Detection Flow The following flow chart describes the sleeping cell detection operation.


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GUI for Sleeping Cell Detection Among eNBs of which condition are not in the exception case for sleeping cell detection, when the number of normal CRR is lower than the threshold and aggregated number of normal CRR during the range is lower than the threshold, sleeping cell detection alarm is generated and is reflected on the Event Viewer as shown in the following figure.

When a sleeping cell detection alarm is generated, the sleeping cell detection alarm can be cleared for the following conditions: oWhen the number of the normal CRR is higher than the threshold during the unit period (15 min). eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oWhen the number of the normal CRR is lower than the threshold but aggregated number of normal CRR during the range is higher than the threshold. The cleared sleeping cell detection alarm is reflected on the Event Viewer as shown in the following figure.

SYSTEM OPERATION How to Activate The following figure shows GUI for sleeping cell detection configuration parameter setting. Description of each parameter for sleeping cell detection configuration can be found in the table below.

If you want to change the parameters for detecting sleeping cell of an eNB, double-click the row for the eNB listed in the sleeping cell detection configuration list. After entering sleeping cell setting window, you can set function ON/OFF, threshold, and parameters for three periods (range, start hour, and end hour). By clicking the Apply button, you can apply configuration for sleeping cell detection for the eNB.

Key Parameters The following window is for sleeping cell setting. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The detailed descriptions of Sleeping Cell Setting parameters are as follows: Parameter

Description

Cell

Setting information to detect sleeping cells.

Threshold

Threshold information of sleeping cell.

PERIOD_1ST


Duration for checking whether the cell is sleeping cell or not during period 1st.

Start Hour

The start time of the period 1st; it should be equal to or less than the period 1st end hour.

End Hour

The end time the period 1st; it should be equal to or greater than the period 1st start hour.


Duration for checking whether the cell is sleeping cell or not during period 2nd.

Start Hour

The start time of the period 2nd; it should be equal to or greater than the period 1st end hour and should be equal to or less than the period 2nd end hour.

End Hour

The end time of the period 2nd; it should be equal to or greater than the period 2nd start hour.


Duration for checking whether the cell is sleeping cell or not when the detection time is not in Period 1 or 2.

Family Display Name

Type Name

Type Description

Random Access Preambles

No_FAULT

The call is terminated normally.

S1AP_cs_fallback_trigge red

It occurs when the call is released because the inter-RAT redirection occurs due to CSFB.

S1AP_interrat_redirectio

It occurs when redirection is processed normally due to

PERIOD_2ND

PERIOD_ALL

Counters and KPIs


722


Type Name n

Type Description the inter-FA redirection.

S1AP_redirection_towar ds_1xRTT

The call is released due to redirection to 1xRTT.

ECC_USER_INACTIVIT Y

It occurs when the MACB block detects the user inactivity and notifies the fact to the ECCB block due to no traffic transmission during the given period of time (user inactivity time) for a specific UE.

ECC_INTER_FA_REDIR ECTION

It occurs when the redirection to the inter FA is handled.

REFERENCE N/A


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LTE-SO0602, Cell Outage Compensation INTRODUCTION Samsung Cell Outage Compensation (COC) adjusts the transmission power of RRH automatically, if the outage occurs for a specific cell during the operation of LTE system to compensate a cell outage area. Also, this consists of cell outage detection, cell outage compensation, and cell outage clear functions.

Cell outage detection oThe eNB detects the occurrence of cell outage and if the cell outage occurred, it reports cell outage to the EMS.

Cell outage compensation oIf the EMS receives report on the cell outage from eNB, it selects a cell to participate in the COC to compensate the cell outage and determines the transmission power of RRH of the cell. The cell to participate in COC is excluded from the Coverage and Capacity Optimization (CCO). oThe EMS transmits to eNB the transmission power of RRH of the cell to participate in COC as determined above. oThe eNB applies the received transmission power of RRH.

Cell outage clear oIf the cell outage is released, eNB reports it to the EMS. oIf the EMS receives report on the release of the cell outage, it sets the transmission power of RRH of the outage cell. As a result, the cell to participate in the COC before cell outage as the transmission power value and transmits it to eNB. At the time, the outage cell and the cell to participate in COC are included against as targets for CCO. oThe eNB applies the received transmission power of RRH. The transmission power of RRH of each cell may be controlled by CCO function and COC function. To prevent conflicts between the two functions, COC function has the higher priority than CCO function. Accordingly, if both CCO function and COC function are operated, the transmission power of RRH is adjusted as follows:

If a specific cell is participating in COC, in other words, if the cell uses the maximum transmission power to compensate the outage area, the transmission power of RRH of the cell is not adjusted by CCO function.

If the specific cell does not participate in COC, the transmission power of RRH of the cell may be adjusted by CCO function.


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BENEFIT Operator can reduce operational cost by automatic cell outage detection and compensation functions.

After cell outage occurs, users in cell outage area can be in service in a short time.

DEPENDENCY AND LIMITATION Dependency:

This feature supports only Macro and Outdoor Pico systems. Limitations:

In case that Tx power of the COC candidate cell is set to maximum value, its Tx power value is not changed anymore when outage of its neighbor cell is detected.

FEATURE DESCRIPTION Network Structure The network architecture for COC in LTE system is as shown below. The main network entities (NEs) in the network architecture include eNBs and EMS. The connection between EMS and eNB represents a management interface. Also, eNBs and EMS exchange information for the performance of COC through the management interfaces. The following figure is Network architecture for COC in LTE system:


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The main NEs for the operation of COC are as follows:

eNB oDetects a cell outage oReports occurrence of the cell outage to the EMS. oReceives transmission power by RRH of the cell to participate in the COC to compensate the cell outage from the EMS. Applies transmission power of RRH of the cell. Delivers information on the changed transmission power of the RRH through SIB2. oIf the cell outage becomes clear, reports it to the EMS. oReceives transmission power by RRH before the occurrence of COC of the outage cell and the cell participating in COC from the EMS. Applies transmission power of RRH of the cell. Delivers information on the changed transmission power of the RRH through SIB2.

EMS oReceives the occurrence of a cell outage from eNB. oDetermines a cell to participate in COC. Saves the information on the outage cell and the cell to participate in COC. oExcludes the cell to participate in COC from the operation of CCO. Determines transmission power of the cell to participate in COC. Delivers transmission power of the cell to participate in COC to eNB. Receives the cell outage clear from eNB. (Check the status of eNB cell regularly.) If the cell outage becomes clear, includes the cell to participate in COC in the targets for COC. Delivers the transmission power by RRH before the occurrence of COC of the outage cell and the cell participating in COC.

COC Operation Procedure The operation procedure of Samsung COC is as follows:


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1 The eNB detects occurrence of the cell outage. 2 The eNB delivers the CELL_OUTAGE_DETECTION message including the information on the outage cell to the EMS.

3 The EMS selects a cell to participate in COC among the neighbor cells of the outage cell.

4 The EMS stores the information on the outage cell and the cell to participate in COC (for example, eNB ID, cell ID, and transmission power of RRH before the occurrence of the cell outage).

5 The EMS excludes the cell to participate in COC from the operation of CCO. 6 The EMS determines transmission power of RRH of the cell to participate in COC.


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7 The EMS delivers the COC_COMP_RRH_TX_POWER_RECONFIG message including the transmission power by RRH for the cell to participate in COC managed by eNB to the eNB including the cell to participate in COC.

8 The eNB sets the transmission power of the RRH depending on the transmission power of the cell to participate in COC included in the COC_COMP_RRH_TX_POWER_RECONFIG message.

9 The eNB delivers the information on the changed transmission power of the RRH through SIB2.

10 The EMS checks status of the cell regularly until it receives the CELL_OUTAGE_CLEAR message from eNB or status of the outage cell is enabled.

11 The eNB performs cell outage recovery. 12 The eNB delivers the CELL_OUTAGE_CLEAR message including the information on the cell to the EMS, if the cell outage is relieved.

13 The EMS checks whether it receives the CELL_OUTAGE_CLEAR message or status of the outage cell is enabled.

14 The EMS includes a cell whose outage is released to participate in COC in the target for CCO.

15 The EMS delivers the COC_COMP_RRH_TX_POWER_RECONFIG message including the transmission power by RRH before outage occurrence of the cell relating to COC managed by the eNB to the eNB including the COC-related cell (the cell whose outage is relieved and the cell to participate in COC).

16 The eNB sets the transmission power of the RRH depending on the transmission power of the COC-related cell by RRH to the COC_COMP_RRH_TX_POWER_RECONFIG message.

17 The eNB delivers the information on the changed transmission power of the RRH through SIB2.

COC Algorithm (Sub1) Cell Outage Detection The eNB detects the occurrence of the cell outage for the cell outage detection function and reports it to the EMS.

1 Detecting the occurrence of a cell outage Samsung COC function defines an outage cell as follows: oIf status of the cell is maintained as being disabled during a specific period of time (DisableDuration) If status of the cell is disabled due to the lock by operator, the cell is not considered as an outage cell.

2 Reporting the occurrence of the cell outage to the EMS If the cell managing by eNB is decided as an outage cell, the eNB reports the CELL_OUTAGE_ DETECTION message to the EMS. The CELL_OUTAGE_DETECTION message includes followings: eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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oOutageeNBID: The ID of eNB transmitting the CELL_OUTAGE_DETECTION message oOutageCellID: The ID of the cell where the outage occurs oTxPdBm: The transmission power of RRH of the cell where the outage occurs (Sub2) Cell Outage Compensation When the EMS receives the CELL_OUTAGE_DETECTION message from eNB, it performs the following procedure:

1 Selecting the cell to participate in COC and saving the relevant information 2 Excluding the cell to participate in COC from the operation of CCO 3 Determining the transmission power of the RRH of the cell to participate in COC

4 Delivering and applying the transmission power of the RRH of the cell to participate in COC

5 Checking status of the outage cell regularly The detail for the aforementioned procedure is as follows:

(Sub2) Selecting a cell to participate in COC and determining the transmission power of the RRH (Procedures from 1 to 3) The EMS checks the outage cell from the CELL_OUTAGE_DETECTION message transmitted by eNB, and checks the value of FrequencyRange (= Intra-Frequency or Inter-Frequency) of SON Property. In case that FrequencyRange = Intra-Frequency, cells satisfying all the following conditions are selected to participate in COC for the outage cell: oAmong neighbor cells in outage cell‟s NRT, neighbor cell using the same frequency with the outage cell oCells set to participate in COC oIf the handover attempt count to the cell during a day exceeds zero In case that FrequencyRange = Inter-Frequency, cells satisfying all the following conditions are selected to participate in COC for the outage cell: oAll the neighbor cells in outage cell‟s NRT oCells set to participate in COC oIf the handover attempt count to the cell during a day exceeds zero The EMS saves eNB ID, cell ID, and the current transmission power of the RRH for the outage cell and the selected cells to participate in COC through the aforementioned conditions. After excluding the cells to participate in COC from the CCO operation, the EMS sets the transmission power of the RRH of the cell to the transmission power to the maximum.

(Sub2) Delivering and applying the transmission power of the RRH of the cell to participate in COC (Procedure 4)


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The EMS delivers to eNB that manages the cells to participate in COC transmission power of the RRH of the pre-determined cells to participate in COC through the COC_COMP_RRH_RX_POWER_RECONFIG message. The COC_COMP_RRH_RX_POWER_RECONFIG message includes the eNB ID, ID of the cell to participate in COC, the RRH index of the cell, and the transmission power value of the RRH. The eNB that receives the COC_COMP_RRH_TX_POWER_RECONFIG message sets the transmission power of the RRH of the cell managed by the eNB to the transmission power value in COC_COMP_RRH_TX_POWER_RECONFIG. After changing the power transmission of the RRH, eNB delivers to UE the information on the changed power transmission of the RRH through SIB2.

(Sub2) Checking status of the outage cell (Procedure 5) After sending the COC_COMP_RRH_TX_POWER_RECONFIG message, the EMS checks status of the outage cell regularly until the following conditions are satisfied: oReceiving the CELL_OUTAGE_CLEAR message from eNB which manages the outage cell oChecking that status of the outage cell is enabled by checking the status of the cell regularly (Sub1) Cell Outage Clear When the EMS receives the CELL_OUTAGE_CLEAR message from eNB or checks whether status of the outage cell is enabled, the following operation is performed:

1 Detecting and reporting cell outage clear 2 Including the cells to participate in COC in the cells for CCO 3 Determining the transmission power of the RRH of the COC-related cells (the outage cell and cells to participate in COC) before occurrence of the cell outage

4 Delivering and setting the transmission power of the RRH of the COC-related cells The detail for the aforementioned procedure is as follows:

(Sub2) Detecting and reporting cell outage clear (Procedure 1) aIn case of detecting cell outage clear by reporting to eNB If status of the outage cell is changed from disabled to enabled, the eNB decides the outage of the cell is cleared and reports the CELL_OUTAGE_CLEAR message to the EMS. The CELL_OUTAGE_CLEAR message includes the cell ID information of the cell whose outrage is released.

bIn case of detecting the release of cell outage through checking the status of the cell of EMS periodically The EMS checks status of outage cell regularly and if status of outage cell is changed to enabled, the EMS decides the status as cell outage clear. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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(Sub2) Recovering the transmission power of the COC-related cell (Procedure from 2 to 3) When the EMS checks the release of the cell outage (whether the status of the cell is enabled by receiving the CELL_OUTAGE_CLEAR message from the eNB or through the regular checkup of the EMS), the EMS includes the cell to participate in COC again in the cell for CCO. After that, the EMS determines the transmission power of the RRH of the COC-related cells (an outage cell which is released and a cell to participate in COC) as the saved value when the cell outage compensation operation is performed.

(Sub2) Delivering and setting the transmission power of the RRH of the COCrelated cell (Procedure 4) The EMS transmits transmission power value of the RRH pre-determined to eNB through the COC_COMP_RRH_TX_POWER_RECONFIG message. The COC_COMP_RRH_TX_POWER_RECONFIG message includes the eNB ID, IDs of the cells to participate in COC, the RRH index of the cell, and the transmission power value of the RRH. The eNB that receives the COC_COMP_RRH_TX_POWER_RECONFIG message sets the transmission power of the RRH of the COC-related cell as the transmission power before the occurrence of the cell outage included in the message. After that, eNB delivers the information on the changed transmission power of the RRH through SIB2.

SYSTEM OPERATION How to Activate The operator sets the COC operation to auto or manual of the SON_COC_FUNC_ENABLE value of eNB to operate the COC to activate the COC operation. In addition, the operator sets the SON_CCO_PWR_CTRL_ENABLE value of the cell to change the transmission power to auto through the COC operation. Provided, however, that the SON_COC_PWR_CTRL_ENABLE value cannot be applied as auto for the cell in the eNB whose SON_COC_FUNC_ENABLE is Off. The CCO operation-related parameter settings are as follows:

FrequencyRange: Frequency range considered when selecting cells to participate in COC

DISABLE_DURATION: Waiting time to decide as cell outage Key Parameters The operator may set frequency range considered when selecting cells to participate in COC by using FrequencyRange of SON Property. Parameters

Description

FrequencyRange

Frequency range which will be considered when selecting cells to participate in COC


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The operator may change and retrieve the operating mode, either automatic or release, in Samsung COC by using the following commands and parameters: CHG-SONFN-ENB/RTRV-SONFN-ENB Parameters

Description

SON_COC_FUNC_ENABLE

In SON, determines the enable of the cell outage compensation (COC) SON. Off: Turn off the function. Manual: Turn on the function. The operator applies the COC result after checking it. Auto: Turn on the function. Apply the COC result automatically.

The operator may change and retrieve the Tx power changing mode of each cell by COC, either automatic or release, by using the following commands and parameters: CHG-SONFN-CELL/RTRV-SONFN-CELL Parameters

Description

SON_COC_PWR_CTRL_ENA BLE

In SON, determines the enable of the transmission power changing function by the cell outage compensation (COC) algorithm. Off: Turn off the function. Auto: Parameters may be changed by an algorithm.

Counters and KPIs Samsung COC function uses the following statistical information. Family Display Name

Type Name

Type Description

HO_INTRA

IntraEnbSucc


HO_X2_OUT

InterX2OutAtt

The number of X2 HO execution attempt to inter-eNB neighbor cell

HO_S1_OUT

InterS1OutAttempt

The number of S1 HO execution attempt to inter-eNB neighbor cell

REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 9) [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 9) [3] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [4] 3GPP 32.500: E-UTRAN; Concepts & Requirements [5] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases


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LTE-SO0603, Sick Cell Detection INTRODUCTION The sick cell detection feature provides the user interface showing whether the cell state reaches the performance limit or not based on the performance statistics at the normal or warning state. Accordingly, the system operator can easily know whether the cell reaches performance limit in the use of wireless or backhaul resources or not through the sick cell detection feature.

BENEFIT If a warning frequently occurs in the same cell over a certain period of time, the system operator may use such situation as reference for expansion of cell or backhaul.

DEPENDENCY AND LIMITATION Dependency eNB should provide the statistics used for the calculation of the cell state to EMS. Limitation EMS can calculate the cell state for 2 hours/1 day when the statistics for 15 minutes/hour are used if statistics for the period are stored in EMS.

FEATURE DESCRIPTION eNB Load Definition The sick cell detection feature provides a GUI showing the state (normal or warning) of a cell that reaches performance limit in the use of wireless or backhaul resources for a certain period of time. The system operator may check the eNB traffic statistics (minimum, average, and maximum) for a certain period of time (day, hour) through the EMS GUI. The following table shows the congestion-indicating metric by using eNB counter. eNB Status

Quality Indicator

eNB Counter

Congestion-indicating Metric

Insufficient air resources

Air Resource Usage

DL/UL PRB(*) Usage

Number of RRC Connected Users

RRC connected User

(Normalized NGBR DL Throughput per UE < M) (Normalized NGBR UL Throughput per UE < N)

Air Throughput

DL/UL Throughput

Backhaul Usage

Rx/Tx Backhaul Usage

Insufficient backhaul


(Rx Backhaul Usage > A) && (Normalized NGBR DL Throughput per UE < M) 733

Chapter 8 SON eNB Status resources

Quality Indicator

eNB Counter

Air Resource Usage

DL/UL PRB(*) Usage

Number of RRC Connected Users

RRC connected User

Air Throughput

DL/UL Throughput

Congestion-indicating Metric (Tx Backhaul Usage > B) && (Normalized NGBR UL Throughput per UE < N)

(*) PRB: Physical Resource Block

Setting the Thresholds (M, N, A, B) M, N, A, and B are thresholds to decide the state of the wireless and backhaul resource. The thresholds are decided by the throughput policy and actual network operation scenario, and may be changed by the system operator. The following table shows an example of default values for thresholds used in Samsung Sick cell Detection feature. Threshold

Samsung Default Value

M

512 kbps

N

128 kbps

A

70 %

B

70 %

Criteria for Determining Load Status Congestion-indicating Metric for Air Resources In general, wireless resources are preferentially allocated to guaranteed bit rate (GBR) traffic and the left wireless resources to non-guaranteed bit rate (NGBR) traffic. Accordingly, whenever the number of users who use NGBR increases, the NGBR throughput per user decreases. On assumption that the service quality of the GBR traffic was guaranteed all the time, the dropping of NGBR throughput per user below a threshold can be used as a ground for judging insufficient wireless resources. At the time, when the user uses the low-capacity service, even though the wireless resources are sufficient, the NGBR throughput could be reduced. Therefore, the throughput of the user must be normalized by PRB usage to judge the degrading of the throughput by performance limit. The formula for defining normalized NGBR throughput of each user is as follows:

where available PRB for NGBR users means the maximum available wireless resources to be used for NGBR users and it can be expressed as the sum of current PRB usage of the NGBR traffic and the remaining PRB usage. The following figure shows an example of the calculation of the normalized NGBR throughput by user. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Congestion-indicating Metric for Backhaul Resources If the backhaul resources are not sufficient, even though the wireless resources are sufficient, the whole throughput is degraded due to the backhaul bottleneck phenomenon. Accordingly, the dropping of the NGBR throughput of the user below a threshold due to the operation of the bottleneck of backhaul resources may be used as a reference for judging the insufficient backhaul resources. At the time, when a small number of users use all backhaul resources, the backhaul usage may increase in excess of the threshold value. Therefore, the sick cell detection feature uses the NGBR throughput by user below threshold and the backhaul usage in excess of threshold as a ground for the insufficient backhaul resources.

SYSTEM OPERATION How to Activate GUI for Configuration Parameter Setting The EMS GUI for retrieving statistics information by cell is represented as shown in figure below.

Set a statistics type to retrieve the performance statistics information by using radio buttons of [15 Min] or [1 Hour].


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Set the period for retrieving the performance statistics information by using the [Period] area. (When the performance statistics information is retrieved, only the statistics data included in the period (maximum 2 hours/1 day) is retrieved.)

Set whether how many data could be shown on one page by using the [Rows] combo box.

Check the performance characteristics for a certain period of time as set above by clicking the [Search] button. GUI for Analysis Results The following figure represents the result of performing the sick cell detection feature:

The system operator may check the performance statistics of eNBs registered in the EMS in the figure shown above through the sick cell detection feature.

Under the following cases, the corresponding value is expressed in red and the row of the analysis result is expressed as Warning: oIf Congestion-indicating Metric for Air Resource is smaller than M or N, Throughput, Number of RRC connected Users, and PRB Usage are expressed in red. oIf Congestion-indicating Metric for Backhaul Resource is larger than A or B, Throughput, Number of RRC connected Users, PRB Usage, and Backhaul Usage are expressed in red.

Key Parameters There are no related parameters.


Type Name

Type Description

AIR_RLC_BYTES

AirUlThru

Means the air uplink throughput and is collected for the data received from the UE for each cell and QCI.


736


Type Name

Type Description

AirDlThru

Means the air downlink throughput and is collected for the data sent to the UE for each cell and QCI.

RRC_CONN

ConnNo

Average number of RRC connection per unit time

PRB_TOTAL

TotPrbDl

Ratio of the resource used to transmit the PDSCH/PDCCH against the total downlink resources

TotNGbrPrbDl

Ratio of the resource used to transmit the non-GBR traffic against the total downlink resources

TotPrbUl

Ratio of the resource used to receive the PUSCH against the total uplink resources

TotNGbrPrbUl

Ratio of the resource used to receive the non-GBR traffic against the total uplink resources.

RX_LinkUtilization

Average link utilization of packets received from the outside

TX_LinkUtilization

Average link utilization of packets transmitted to the outside

PACKET

REFERENCE None


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LTE-SO0702, Coverage and Capacity Optimization INTRODUCTION Samsung CCO has the purpose of optimizing the coverage. Also, it is used as a function of adjusting the transmission power of the RRH automatically to optimize the coverage during the operation of LTE system. Samsung CCO consists of three detailed functions as follows:

1 Detecting the occurrence of a coverage hole oDetermines a coverage hole based on the information on the RLF report from UE.

2 Collecting information oCollects and reports the coverage holes, UE in and out and hand-out-related statistics

3 Coverage optimization oDetermines and sets the transmission power of the RRH based on the information on the collected network status.

BENEFIT To reduce the optimization costs during the operation by adjusting the transmission power of the RRH depending on the network status

To guarantee less call drop and seamless service by adjusting the transmission power of the RRH depending on the network status

DEPENDENCY AND LIMITATION Dependency:

RLF report from UE supported: To collect the RF environment information upon the occurrence of the RLF of the UE, the UE must support the RLF report function.

This feature supports only Macro and Outdoor Pico systems. Limitations:

The transmission power of the RRH for the cells to participate in COC determined by COC is impossible to be adjusted.


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FEATURE DESCRIPTION Architecture The figure below shows Samsung CCO-related network architecture and the main network entities include eNBs and the EMS:

The main functions of eNBs and EMS are as follows:

1 eNB oDetects a coverage hole. oCollects information to adjust the transmission power of the RRH (coverage hole, UE in and out and hand-out-related statistics). oReports collected information to the EMS. oReceives transmission power of RRHs from the EMS. oApplies transmission power of the RRH. oDelivers information on changed transmission power of the RRH through SIB2.

2 EMS oCollects information to adjust the transmission power of the RRH from the eNB (coverage hole, UE in and out, and hand-out-related statistics). oDecides transmission power of the RRH based on the received information. oDelivers transmission power by RRH to eNB.


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CCO Function CCO Operation Flow The whole operating flow of Samsung CCO is as follows:

1 The EMS delivers the CCO-related PLD to eNB. 2 The eNB detects a coverage hole based on the RLF report from the terminal. 3 The eNB collects information on the coverage hole-related statistics to detect the coverage hole during the Report period.

4 The eNB collects statistics related to UE in to and UE out from the cell managed by itself during the Report period.

5 The eNB collects statistics related to the hand-out count to the neighbor cell among the cells managed by it during the Report period.

6 The eNB delivers to EMS statistics relating to the collected coverage holes, UE in and out and hand-out during the Report period.

7 The EMS decides transmission power of the RRH considering the network status based on the information collected from eNB (coverage hole-related statistics) at every CCO period.

8 The EMS delivers decided transmission power of the RRH to eNB.


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9 The eNB changes cell configuration information based on the received transmission power of the RRH and delivers the information on the changed transmission power of the RRH to UE through SIB2.

CCO Algorithm Samsung CCO has the purpose of optimizing the coverage. Also, it is used as a function of adjusting the transmission power of the RRH automatically to optimize the coverage during the operation of LTE system. Samsung CCO operates as follows:

1 Detecting a coverage hole oDetermining a coverage hole based on the information on the RLF report from UE

2 Collecting and reporting information oCollecting and reporting the coverage holes, UE In/Out and hand-out-related statistics

3 Deciding the transmission power of the RRH oDeciding transmission power of the RRH based on the information on the collected network status

4 Configuring the transmission power of the RRH oApplying transmission power of the RRH decided to the RRH oChanging and delivering to UE the system parameters depending on the decided transmission power of the RRH Detailed explanation on the detailed operations of each algorithm is as follows:

(Sub2) Detecting a coverage hole When the RLF is generated by using the RLF report information (serving RSRP, serving RSRQ or neighbor RSRP) from UE, the eNB determines the occurrence of the coverage hole if the predicted SINR is less than the SINR threshold.

(Sub2) Collecting and reporting coverage hole statistics When a coverage hole is detected during the CCO period, eNB calculates the difference of the transmission power of the serving cell or neighbor cell. Also, the both cells are having the same frequency with serving cell to remove the coverage hole and collect the coverage hole-related statistics (count of calculating difference of transmission power, and sum of the difference of the transmission power). Besides, eNB collects the statistics relating to UE in to, or UE out from, the cell managed by it during the Report period. The eNB reports to the EMS the statistics relating to the collected coverage holes, UE in-and-out and hand-out during the Report period.

Deciding the transmission power of the RRH


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The EMS calculates the transmission power of the cell in every CCO period to remove the coverage hole by using the statistical information relating to the coverage hole, UE in-and-out and hand-out received from eNBs (count of calculating difference of transmission power, and sum of the difference of the transmission power) which are collected during CCO period as follows:

aEMS calculates each cell‟s count of calculating difference of transmission power and the count of UE in-and-out based on the statistical information from eNB. For the count of calculating difference of transmission power and the count of UE in-and-out, only the information that are collected by neighbor cell with the same cell type (macro cell or pico cell).

bEMS calculates the ratio of the coverage hole for the current transmission power of the cell by using the count of calculating difference of transmission power and the count of UE in-and-out as shown below, and calculates average coverage hole ratio based on IIR filtering. Coverage hole ratio = count of calculating difference of transmission power/UE in and out count The above average coverage hole ratio for the transmission power of the cell represents the degree of the occurrence of the coverage hole based on the transmission power of the cell.

cEMS calculates sum of the difference of transmission power and the count of calculating difference of transmission power by using the information on the statistics from eNB. For the calculation of each cell‟s sum of the difference of transmission power and the count of calculating difference of transmission power, only the information collected by neighbor cell with the same cell type (macro cell or pico cell) is considered.

dEMS calculates the candidate transmission power for each cell to remove the coverage hole by using the sum of the difference of transmission power and the count of calculating difference of transmission power as follows: Candidate transmission power = current transmission power + (the sum of the difference of the transmission power/count of calculating difference of transmission power)

eEMS decides the transmission power of each cell by using the average coverage hole ratio within the scope of [candidate transmission power and current transmission power] of the cell in a direction to removing the coverage hole. However, the collected statistical information for the cell whose UE in-and-out count is less than UE in-and-out count threshold is saved and the transmission power is maintained as it is. Additionally, to prevent the coverage hole area from being increased by reducing the transmission power of the cell and the neighbor cell, if there is a neighbor cell whose hand-out account exceeds the hand-out threshold and whose state of transmission power is reduced for the cell whose transmission power is determined to be reduced through the aforementioned course, the transmission power is prohibited from being reduced and the current transmission power is maintained.


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(Sub2) Configuring the transmission power of the RRH EMS delivers the decided transmission power of the RRH of the cell to eNB. The eNB configures the RRH transmission power of the cell with that of the cell received from the EMS. Also, it transmits information on the changed RRH transmission power of the cell to UE through SIB2.

SYSTEM OPERATION How to Activate The operator sets the CCO operation to „auto‟ or „manual' of the SON_CCO_FUNC_ENABLE value of eNB to operate the CCO to activate the CCO operation. In addition, the operator sets the SON_CCO_PWR_CTRL_ENABLE value of the cell to change the transmission power to auto through the CCO operation. However, the SON_CCO_PWR_CTRL_ENABLE value cannot be applied as auto for the cell in the eNB whose SON_CCO_FUNC_ENABLE is OFF. The CCO operation-related parameter settings are as follows:

POWER_RANGE: Scope of adjusting the transmission power POWER_STEP_SIZE: Step size used to calculate the difference of the transmission power

COVERAGE_HOLE_SINR: SINR threshold corresponding to the coverage hole UE_IN_OUT_THRESHOLD: UE in-and-out count threshold COVERAGE_HOLE_RATIO_EXPIRE_TIME: Average coverage hole ratio maintaining time

Key Parameters The operator may change and retrieve the operating mode, either automatic or release, in Samsung CCO by using the following commands and parameters: CHG-SONFN-ENB/RTRV-SONFN-ENB Parameters

Description

SON_CCO_FUNC_ENABLE

In SON, determines the enable of the CCO (coverage & capacity optimization) SON. Off: Turn off the function Auto: The changed parameter is automatically applied to operation when the parameter is changed by the algorithm.

The operator may change and retrieve the Tx power changing mode of each cell by CCO, either automatic or release, by using the following commands and parameters: CHG-SONFN-CELL/RTRV-SONFN-CELL


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Description

SON_CCO_PWR_CTRL_ENA BLE

In SON, decide enable of the transmission power changing function by CCO. Off: Turn off the function Auto: Parameters may be changed by an algorithm.

Counters and KPIs Samsung CCO function uses the following statistical information. Family Display Name

Type Name

Type Description

HO_INTRA

IntraEnbSucc


HO_X2_OUT

InterX2OutAtt

The number of X2 HO execution attempt to inter-eNB neighbor cell

HO_S1_OUT

InterS1OutAttempt

The number of S1 HO execution attempt to inter-eNB neighbor cell

HO_X2_IN

InterX2InSucc

The number of X2 HO execution success from inter-eNB neighbor cell to own eNB cell

HO_S1_IN

InterS1InSucc

The number of S1 HO execution success from inter-eNB neighbor cell to own eNB cell

RRC_REESTAB

ConnReEstabSucc

The number of success of RRC_REESTAB

MRO_RLF

TooLateHoRlfBeforeTriggering

RLF occurrence count by too late HO before HO triggering

REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 9) [2] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 9) [3] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [4] 3GPP 32.500: E-UTRAN; Concepts & Requirements [5] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases


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LTE-SO0801, PA Bias Control INTRODUCTION The purpose of Samsung ES is to reduce the operator‟s OPEX and carbon dioxide emission by saving power consumption of the eNB without any coverage or quality of service (QoS) loss during the eNB operation. The Samsung ES function mentioned in this document is an ES method using PA-bias control. This method is a technology that reduces unnecessary energy consumption of the RRH by controlling drain bias voltage of the RU PA while the eNB transmits downlink data. The Samsung eNB operates in the „Normal Mode‟ if the Samsung ES function is not active; The Samsung eNB operates in either of the „ES Mode‟ or „Normal Mode‟ otherwise. If the Samsung eNB operates in the ES mode, a lower value than in the normal mode is applied to the drain bias voltage of the RU PA. The serving DL traffic is limited to no more than a certain level to prevent the increase of the ACLR.

Normal Mode oPA drain bias voltage: normal (for example, 30 V) oAvailable resource block (RB) allocation: 100 % of system bandwidth (BW)

ES Mode oPA drain bias voltage: low (for example, 26 V) oAvailable RB allocation: limited to about 50 % of system bandwidth (BW) The Samsung eNB selects either the „Normal Mode‟ or the „ES Mode‟ as the operation mode of the eNB RU every 1 hour. The selection can be made in the following 2 ways, which is related to the operation mode of the Samsung ES function. When using „Normal Mode‟, the eNB runs in Energy Saving mode only during the hours set by the system operator. When using „ES Mode‟, the eNB makes its own decision on whether to run in Energy Saving mode or normal mode. Below table is a way of determination for execution mode and its relation to operation style of Samsung ES. Operation style of Samsung ES

Execution mode determination

Manual Apply

Based on pre-defined time schedule

Automatic Apply

Based on automatic and periodic traffic analysis

BENEFIT Reduction of OPEX without coverage/QoS loss by operating when traffic load is small. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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DEPENDENCY Related Radio Technology Radio Technology: E-UTRAN (LTE)

Prerequisite Features LTE-ME3309 feature should be operated for 5 MHz BW systems.

LIMITATION This feature cannot be used when RU is shared by multi RATs (such as CDMA, Wi-MAX).

This feature cannot be applied when RU is shared by multi eNBs. PA bias control cannot be activated on only one PA. All PAs in RU will be controlled together.

This feature cannot be applied to small cell systems. This feature cannot be applied to under 5 MHz BW (e.g. 1.4 MHz, 3 MHz) systems.

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Performance and Capacity PA Bias Control feature limits the number of allocated RBs in energy saving mode. The peak throughput will be decreased according to the limited number of RBs.

FEATURE DESCRIPTION Architecture Below figure shows the structure of the Samsung ES function. The EMS and eNB have blocks related to the ES function.


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The SON-Manager is a software block located in the EMS and performs energysaving functions. The role of the ES-related function of the EMS SON-manager is to support the system operator to set ES function-related settings using the PLD and to transmit the settings to the eNB OAM. The setup information transmitted to the eNB OAM by the SON-manager is largely divided into the following three.

Enable/disable settings of the ES function Automatic apply (traffic analysis/prediction)-related parameter settings Manual apply (pre-defined schedule based ES)-related parameter settings The EMS SON-manager also receives reports on the operation status of the eNB‟s ES function. Function blocks for the implementation of the ES in the eNB are the SON-Agent, OAM, scheduler and RU control blocks.

1 SON-Agent of eNB This function block determines the ES mode based on the time-varying traffic information collected during the system operation and allows the scheduler and the PA to perform operations set by each mode. To do this, the SONAgent consists of the following function blocks. oTraffic Load Analysis Module oTraffic Prediction Module oES Mode Management Module

2 OAM of eNB This function block collects statistics information from the scheduler and provides it to the SON-Agent. Also, the OAM performs as a bridge of information transfer between the EMS SON-Manager and the eNB SONAgent.

3 Scheduler of eNB


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This function block performs the resource allocation restriction/release function according to the operation mode, as instructed by the SON-Agent function block.

4 RU control of eNB The RU control block communicates with the SON-Agent function block to control the bias voltage of the power amplifier corresponding to the operation mode.

Operation Figure below illustrates the overall operating procedure of the Energy Saving function described in this document. The following symbols are used:

X(i): traffic load estimation value during the time interval [i, i + 1]. Y(i): traffic load measurement value during the time interval [i, i + 1]. Mode(i): eNB operation mode during the time interval [i, i + 1]. Mode(i, p): time interval [i, i + 1] consists of “P” number of short time intervals, and Mode (i,p) indicates the eNB operation mode during the pth short time interval.


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Operation when Energy Saving Function is Disabled If the system operator has not enabled the Energy Saving function, the eNB does not perform any additional actions for the function but instead runs in normal mode. If the system operator stops the Energy Saving function in the Automatic or Manual mode during system operation, the eNB immediately switches from the Energy Saving function to the normal mode. Operation when Energy Saving Function is Running in Manual Mode If the system operator enables the Energy Saving function in Manual mode, the operator must write the Energy Saving function schedule table, which consists of one-hour blocks by day of the week and by hour. The Energy Saving function operation schedule table of each cell uses the format as shown below. When the system operator writes or edits this schedule table for the first time, the EMS notifies the eNB of the corresponding cell. At the turn of every hour, the eNB retrieves this schedule table for its operation mode and enables the operation mode specified therein. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Hour block

Time interval

eNB operation mode

Sunday

0

00:00-01:00

Either normal mode or Energy Saving mode

1

01:00-02:00


⁞

⁞

⁞

23

23:00-24:00


0

00:00-01:00


1

01:00-02:00


⁞

⁞

⁞

23

23:00-24:00


⁞

⁞

⁞

⁞

Saturday

0

00:00-01:00


1

01:00-02:00


⁞

⁞

⁞

23

23:00-24:00


Monday

Even when running in the ES Mode, if the eNB encounters a sudden increase of traffic or an eNB error, it stops the ES Mode and reverts to Normal Mode. When the Energy Saving function is enabled in Manual mode, the conditions for the mode are the same as when the Energy Saving function is enabled in Automatic mode. Operation when Energy Saving function is running in Automatic mode The SON-Agent function block of eNB performs the following actions every hour.

1 Analyzes the traffic load for “D” number of days in the past leading up to the present moment.

2 Using this data, estimates the traffic load required for the next 1 hour. 3 Based on the traffic analysis and estimation, selects whether to run in ES Mode or Normal Mode for the next 1 hour.

4 Instructs each of the eNB function blocks to perform the actions corresponding to the selected operation mode. Traffic Prediction The traffic load for the upcoming 1 hour is predicted as the larger value of the following two metrics.

Time series average of the traffic load at the same hour for past D days Weighted moving average of the traffic load for the recent M hours Determination of Execution Mode The Samsung ES function determines the operation mode for the upcoming 1 hour every hour on the hour. When the following condition is fulfilled, the eNB runs in ES Mode for 1 hour.

The estimated traffic load must be equal to or less than the threshold values. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The threshold values used are defined in Table 1 below. Note that the values in this table are subject to change at the time of hardware and software provision. Mode

Threshold

Traffic Load

PA Bias Voltage

Normal mode

100 %

100~50 %

30 V

ES mode

50 %

50~0 %

26 V

Conditions for stopping ES Mode The Samsung Energy Saving function described in this document determines whether or not to continue in Energy Saving mode, by checking for temporary and sudden traffic increases or for an increase in the downlink re-transmission rate and block error rate every time the statistics data is collected. Even when running in ES Mode, the eNB switches to Normal Mode if:

1 The ratio of resources available for allocation in ES Mode to the traffic load measurement exceeds the threshold;

2 The ratio of the fourth HARQ re-transmission to the sum of the first HARQ transmission, re-transmission, third re-transmission, and fourth re-transmission exceeds the threshold;

3 The Block Error Rate (BLER) of the fourth HARQ re-transmission exceeds the threshold; or

4 The RLF ratio exceeds the threshold. These four thresholds can be set by the system operator on the EMS.


How to Activate Preconditions There is no specific Preconditions Activation Procedure Run CHG-SONFN-CELL and set ENERGY_SAVINGS_ENABLE to manual or auto Deactivation Procedure Run CHG-SONFN-CELL and set ENERGY_SAVINGS_ENABLE to off

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature.


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Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SONFN-CELL/RTRV-SONFN-CELL Parameter

Description

ENERGY_SAVINGS_ENABL E

Controls SON Energy Saving in 3 modes. Off: The Energy Saving functions except for traffic analysis is disabled. Manual: The Energy Saving function in accordance with the schedule set by the operator is enabled. Auto: The Energy Saving functions based on the information obtained from traffic analysis is enabled.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ES-SCHED/RTRV-ES-SCHED Parameter

Description

CELL_NUM


WEEK_DAY

The day for which the Energy Saving function is operated according to the schedule.

HOUR

This parameter is the activation time (h) of the energy saving feature according to the schedule.

ES_STATE

This setting is required for enabling the energy saving feature using the schedule. Inactive: The energy saving feature does not run. Active: The energy saving feature runs based on the schedule.

SCHEDULED_ES_MODE

ES Mode type in which the Energy Saving function is operated during one hour according to the schedule.

Parameter Descriptions of CHG-ES-COM/RTRV-ES-COM Parameter

Description

DATA_VALIDITY

This parameter is the number of days of traffic analysis to be used in calculating the estimates for determining Energy Saving (ES) mode. For traffic estimation, the average traffic load statistics are calculated for the specified time over the last 15 days or the last 30 days as determined by this parameter.

MOVING_AVERAGE_VALIDI TY

This parameter determines how many hours of data are used for calculating the traffic estimates. When this parameter value is determined, it is weighted with the MOVING_AVERAGE_WEIGHT parameter for calculating the traffic estimates.

MOVING_AVERAGE_WEIGH T

This parameter is the weight of the recent hours to apply moving average for calculating the traffic estimates. When the number of hours (h) of data to use is determined by the MOVING_AVERAGE_VALIDITY parameter, this parameter value is used as weights for data of each hour for calculation. Also, the first weight of this parameter indicates the most recent hour. If MOVING_AVERAGE_VALIDITY is 2 hours and this parameter is 50, 50, 0, 0, 0, 0, 0, 0, 0, 0, it means that a weighting of 50 % is applied to the last 2 hours.


752


Description

RE_TX_THRESHOLD

This parameter is the 4th Re Tx (third retransmission count of PDSCH HARQ) threshold value for determining system abnormality. The unit used is %. This refers to the ratio of the 4th value over the sum of the 1st through 4th values of the no. of DL transmission values in the statistics item DLHARQ status. If the no. of DL transmission value exceeds the major alarm threshold value, it is deemed as a system abnormality. Before starting the Self-Organizing Network (SON) Energy Saving (ES) feature, it must be determined whether the current system status is normal. Therefore, if the system is in abnormal status, the energy saving mode is disabled and the normal mode is enabled. The energy saving feature remains disabled until the system abnormality is resolved.

BLER_THRESHOLD

This parameter is the 4th Re Tx BLER (PDSCH BLER for the third HARQ retransmission) threshold value for determining system abnormality. The unit used is %. This means the BLER for the 4th transmission among the DL residual BLER values of the statistics item DL-HARQ status. If the DL residual BLER value exceeds the major alarm threshold value, it is deemed as a system abnormality. Before starting the Self-Organizing Network (SON) Energy Saving (ES) feature, it must be determined whether the current system status is normal. Therefore, if the system is in abnormal status, the energy saving mode is disabled and the normal mode is enabled. The energy saving feature remains disabled until the system abnormality is resolved.

RLF_THRESHOLD

RLF Threshold for system abnormality.

ALLOCATION_REDUCTION_ FACTOR

Allocation Reduction Factor for Traffic Abnormality

AUTO_ES_MODE

Es Mode when Energy Saving is operated by Auto Apply.

Parameter Descriptions of RTRV-ES-TYPE Parameter

Description

ES_MODE_INDEX

This parameter is the index used for saving the information of each Energy Saving (ES) mode.

ES_MODE_TYPE

This parameter is the Energy Saving (ES) mode to be activated when the traffic load estimate is lower than ES_MODE_ENTERING_THRESHOLD and ES_MODE_LEAVING_THRESHOLD. Normal: Runs on Normal Mode Voltage and RB count. Mode (#): Runs with variable voltage and RB count according to the mode. The higher the mode, the less voltage and RB count are used to save energy.

ES_MODE_PREDICTION_TH RESHOLD

ES Mode Prediction Threshold

ES_MODE_RB_ALLOCATIO N_THRESHOLD

ES Mode RB Allocation Threshold

Counters and KPIs 1 DL PRB Usage This is a statistical indicator that indicates the traffic load of each cell. Statistics for predicting the traffic for each cell Family Display Name

Type Name

Type Description

DL PRB Usage

TotPrbDl

PRB usage of Downlink DTCH traffic


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2 DL Status ReTx Ratio and DL Status ReTx BLER This is a statistical indicator used to determine whether to stop the execution of Energy Saving mode. Statistics for determining operation mode of Samsung ES function Family Display Name

Type Name

Type Description

Retransmission

DlResidualBLER_Retrans4

Block error rate for the fourth re-transmission.

DlTransmission_Retrans0

Initial HARQ transmission count


Second HARQ re-transmission count


Third HARQ re-transmission count


Fourth HARQ re-transmission count

REFERENCE [1] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 9) [2] 3GPP 36.902: E-UTRAN; Self-configuring and self-optimizing network (SON) use cases and solutions [3] 3GPP 32.501: E-UTRAN; Self-configuration of network elements; OAM Requirements for Self Configuration Use Cases [4] 3GPP 32.541: E-UTRAN; OAM Requirements for Self Healing Use Cases


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LTE-SO0901, Minimization Drive Test Optimization INTRODUCTION Minimization of Drive Test (MDT) is a standardized mechanism to collect the network performance measurements from the commercial UEs with possibly the location information. The collected UE measurement results can be utilized for various purposes, for example, network parameter optimization, coverage hole detection, and so on. Operator can save the cost for network optimization by using MDT feature. Samsung MDT supports two modes of operations, that is, Immediate MDT and Logged MDT. Immediate MDT is targeted on the UEs in Active mode while Logged MDT is performed by the UEs in Idle mode.

BENEFIT Operator can save the cost for collecting the network performance measurement data.

End-used service quality can be enhanced thanks to efficient network optimization conducted by using MDT data

DEPENDENCY Required Network Elements MME, TCE server


Prerequisite Features LTE-OM9003, UE Throughput and RF information Trace

Others For Signaling-based MDT, the core network entities shall support the corresponding functions.

LIMITATION For Logged MDT, UE shall support the corresponding functions (Rel.10 or later). Number of UEs for reporting M2, M3, M4 is limitted to 6 UEs per cell. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Collection perioids of M2, M3, M4 are fixed as 2.56 sec. M5 (Scheduled IP Throughput) and Angle of Arrival (in ECID raw data) information trace is not available.

SYSTEM IMPACT This section describes how this feature impacts the network functions and capabilities. Interfaces Added or modified MDT information may affect interface with External Server, so it is required to discuss in advance.

FEATURE DESCRIPTION Optimization of radio network performance is very important task for mobile operators. Conventionally, operators conduct drive test to collect the radio measurement, and parameter optimization is performed based on the gathered information. Mobile operators have spent a lot of time and money for conventional drive test and network optimization. Minimization of Drive Test (MDT) feature is introduced in 3GPP Rel.10 to provide more cost-efficient method to measure and optimize the network performance. Since the mobile devices exist over whole network areas, MDT procedure utilizes UE's measurement capability to acquire the information of network. Through the standardized MDT procedures, operators order some UEs to measure the network performance, and collect the measured data in the server which is called Trace Collection Entity (TCE) in 3GPP specification. Then, the collected information can used for many purposes including coverage hole detection, capacity optimization, and so on. By using this feature, the operator can reduce the cost for gathering the measurement data and optimizing the network parameters. Furthermore, MDT can be more efficient method than the conventional drive test for some areas where the conventional drive test is not very efficient, for example, in-building environment. MDT Configuration parameters may be delivered to the target UE and measurement data can be collected by the UE itself during idle state (Logged MDT), or MDT data collection can be done at the serving eNB by reusing the existing RRM procedures while the target UE stays in connected state (Immediate MDT). There are two types of methods to configure and manage MDT, which are Signaling-based MDT and Management-based MDT.

Signaling based MDT: Used to collect the measurement data of a specific UE based on IMSI or IMEI SV. The MDT configuration message is sent from MME to eNB.


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Management based MDT: Used to collect the measurement data in a specific area. The MDT configuration message is sent directly from RAN OAM server to (set of) cells without specifying target UEs. Some UEs in the area are chosen by eNB for MDT operations. Because MDT management reuses the existing Trace architecture, the two methods have almost same architecture as Signaling-based and Management-based Trace methods, respectively. The following table summarizes the differences of Signaling and Managementbased MDTs. Signaling-based MDT

Management-based MDT

Configuration path

(Core) OAM  HSS  MME  eNB

(RAN) OAM  eNB

Reusing trace procedures

Signaling based trace, for example, Call Trace

Management based trace, for example, Cell Traffic Trace

Target of configuration

Specific subscriber (IMSI) or equipment (IMEI, IMEI SV)

Specific area, for example, cells, TAs

Target UE selection

Target UE selection by OAM

Target UE selection by eNB

User consent checking

User consent checking of the specific UE can be done by HSS before delivering the configuration message.

User consent checking is done by eNB at UE selection based on the saved UE context

Session continuity on cell change

MDT parameter transfer during handover

No MDT session continuity on cell change (Only user consent information can be transferred)

Supported MDTs

Both Logged and Immediate MDT

Both Logged and Immediate MDT

In Signaling-based MDT, a specific UE is chosen by OAM based on IMSI or IMEI SV. The configuration message including the corresponding MDT parameters is sent to HSS for checking the user consent. If subscription data of the user allows MDT, the HSS sends MDT activation message to serving MME of the UE, and the MME sends it to the serving eNB. In Management-based MDT, a specific area is chosen for measurement data collection with MDT parameters. The eNBs in the area choose some UEs and data collection is done based on the received configuration. The user consent for MDT is saved in UE context generally during UE attach, and hence the serving eNB can choose only the UEs which allow Management based MDT data collection. The following figure shows concepts for Signaling and Management-based MDT configuration.


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For UE selection in Management-based MDT, Samsung MDT provides the following options to restrict the scope of chosen users.

UE capability option: 1) All UEs, 2) Rel. 10 or later UEs only, 3) Rel. 10 or later + standalone GNSS capable UEs only. Operator may want to collect only the measurement data with high accuracy.

UE pickup rate: The probability that a UE is chosen for MDT operation when the UE satisfies all the requirements for UE selection. Operator may not want to get measurement data from all the UEs who satisfy the requirements due to large overhead. In the RAN‟s configuration and operation aspects, there are two types of MDT, which are Immediate and Logged MDT. Data collection for Immediate MDT is performed for the connected UEs by eNB, while Logged MDT data collection is performed by each UE itself during idle mode. Immediate and Logged MDT can be configured by both Signaling-based and Management-based MDT configuration procedures. In Immediate MDT, the following types of measurement data can be collected while the UE is in connected mode.

M1: RSRP and RSRQ measurement by UE M2: Power Headroom (PH) measurement by UE M3: Uplink Received Interference Power of the connected cell (Rel.11) M4: DL/UL Data Volume of the UE per QCI (Rel.11) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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M6: Collecting all the event-triggered measurement reports configured for RRM purpose (Rel.11) For collecting data for M1, the eNB‟s RRC configures measurement reporting trigger to the chosen UE. Reporting trigger for M1 can be 1) Periodic or 2) Serving cell becomes worse than threshold; Event A2. The UE sends the measurement report (RSRP and/or RSRQ of serving and neighboring cells) to the serving eNB if the reporting condition is met, and the serving eNB collects the data and sends it to the TCE. On the other hand, no RRC reporting trigger is required for M2 because PHR is carried by MAC signaling. If MDT data collection for M2 is configured, the serving eNB collects the PHR information triggered by normal MAC mechanisms. Similarly, M3 Received Interference Power and M4 Data Volume measurements are also performed by the eNB itself so that no additional RRC signaling is required. If M6 is set, all the existing event-triggered measurement reports configured for RRM purposes are collected, for example, Event A1, A2, A3, A4, A5, A6, B1, and B2 events. Differently from M1, RRC measurement configuration is not additionally configured solely for MDT purpose. However the measured metric is similar to M1, which are RSRP or RSRQ. Location information can be included in the measured data. Two positioning methods are supported, that is, Standalone GNSS/GPS and Enhanced Cell ID (ECID). If GNSS/GPS positioning method is chosen, the serving eNB request UEs to include standalone GNSS/GPS location result as the best effort manner. Then the standalone GNSS/GPS supporting UE can include the detailed location information if data available. If E-CID method is chosen, the serving eNB collects eNB Rx-Tx Time Difference and UE Rx-Tx Time Difference which are the raw data for E-CID. The serving eNB sends the data to TCE, but calculation of detailed location based on collected data is out of scope of the eNB. Among E-CID raw data metrics defined in 3GPP, Angle of Arrival (AoA) trace is not supported. If either GNSS/GPS or E-CID related data is not available, location may be estimated based on signal measurement results for M1, that is, RF fingerprint, according to the TCE implementation. Configuration message of Immediate MDT mainly contains the following information:

List of measurements: M1 (RSRP/RSRQ) and/or M2 (PHR) and/or M3 (Received Interference Power) and/or M4 (Data Volume) and/or M6 (Measurement report collection triggered by RRM events)

Reporting trigger: Periodic or Event A2 (Only for M1) Report amount: Number of measurement reports sent (Only for M1 + Periodic) Event threshold: Reporting threshold for measurement report (Only for M1 + Event A2)

Area scope: Area scope where the MDT data collection should be conducted Positioning method: GNSS/GPS and/or E-CID The eNB immediately starts the MDT operation when it receives the configuration message and the target user is selected. Because Immediate MDT reuses the existing 3GPP standard procedures, the operation is mostly transparent to the UEs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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In Logged MDT, only periodic downlink pilot strength measurement can be performed during idle mode operations. Configuration parameters for Logged MDT are sent to the UE through RRC signaling procedure after the UE transits to the connected state. However, the actual data collection is done while the UE is in idle state. On reception the Logged MDT configuration message over RRC, Logged MDT-capable UE saves the parameters. Then, the UE starts to collect data after the UE‟s state is changed to idle state by considering the saved MDT configuration parameters. After the measurement data is collected during idle mode, UE notifies existence of logged MDT data during RRC connection establishment procedures. Then, the eNB may request the UE to send the logged data, and the received data is sent to the proper TCE based on TCE ID in the logged data. Configuration message of Logged MDT mainly contains the following information:

Logging duration: Logging duration: The timer value for completely stopping the logging job. If the UE‟s state changes from idle to connected state, logging stops for a moment. However, the timer continues independent of state changes. Logging will continue if the UE goes to idle before this timer expires.

Logging interval: Periodicity of measurement during idle mode Trace Reference and Trace Recording Session Reference: Uniquely identifying the MDT session in the whole PLMN

Area scope: Area scope where the MDT data collection should be conducted TCE ID: The ID which uniquely identifying the TCE where the data should be delivered. All the eNBs maintain the unique mapping table for TCE ID to TCE IP address. The following figure describes the concepts for Immediate and Logged MDT operation.


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Additionally, UE RLF reporting (by Rel.9 or later UE) trace and RRC Connection Establishment Failure (RCEF) reporting (by Rel.11 or later UE) trace are also supported as management based MDT trace. RAN EMS orders some cells to trace the RLF or RCEF reports sent by UEs. The, the eNB does not perform any specific triggering action for the trace but just collects the RLF or RCEF information when the reporting is received in the specified area. The collected information is sent to the TCE server.





According to TCE interworking environment, TCE information is configured in the eNB properly.


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UE supports logged measurements in idle mode. Run CHG-MDTCTRL-PARA and set SIG_BASED_IMMEDIATE_MDT_ALLOWED to True to activate signaling based immediate MDT.

Run CHG-MDTCTRL-PARA and set SIG_BASED_LOGGED_MDT_ALLOWED to True to activate signaling based logged MDT.

Run CHG-MDTCTRL-PARA and set MGMT_BASED_IMMEDIATE_MDT_ALLOWED to True to activate management based immediate MDT.

Run CHG-MDTCTRL-PARA and set MGMT_LOGGED_MDT_ALLOWED to True to activate management based logged MDT.

Run CHG-EUTRA-PRD and set ACTIVE_STATE of Mdt purpose to Active to activate periodic measurement for MDT.

Run CHG-EUTRA-A2CNF and set ACTIVE_STATE of Mdt purpose to Active to activate A2 event measurement for MDT. Activation Procedure Register MDT (trace) information using LSM GUI (PERFORMANCE  Call Trace  Register). Deactivation Procedure Delete MDT (trace) information using LSM GUI (PERFORMANCE  Call Trace  Delete).

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MDTCTRL-PARA/RTRV-MDTCTRL-PARA Parameter

Description

SIG_BASED_IMMEDIATE_MDT_ ALLOWED

This parameter shows the whether to permit to the Signaling Based Immediate MDT on demand. False: Signaling Based Immediate MDT request is not allowed. True: Signaling Based Immediate MDT request is allowed.

SIG_BASED_LOGGED_MDT_AL LOWED

This parameter shows the whether to permit to the Signaling Based Logged MDT on demand. False: Signaling Based Logged MDT request is not allowed. True: Signaling Based Logged MDT request is allowed.

MGMT_BASED_ IMMEDIATE_MDT_ALLOWED

This parameter shows the whether to permit to the Management Based Immediate MDT on demand. False: Management Based Immediate MDT request is not allowed.


762


Description True: Management Based Immediate MDT request is allowed.

MGMT_BASED_LOGGED_MDT_ ALLOWED

This parameter shows the whether to permit to the Management Based Logged MDT on demand. False: Management Based Logged MDT request is not allowed. True: Management Based Logged MDT request is allowed.

Parameter Descriptions of CHG-EUTRA-PRD/RTRV-EUTRA-PRD Parameter

Description

PURPOSE

This parameter is the purpose of using EUTRA periodic reportConfig. The ReportStorngestCells is used as ActiveLB, etc. through neighbor cell signal measurement. The ReportCGI is used to acquire the CGI information of a neighbor eNB and mainly used for the purpose of ANR. Mdt

ACTIVE_STATE

This parameter indicates whether EUTRA periodic report is enabled/disabled. If this parameter setting is changed, it will affect the SON operation (e.g. ANR) because EUTRA Periodic Event is utilized for SON such as reportCGI which is used for ECGI request during ANR. Inactive: EUTRA periodic report is not used. Active: EUTRA periodic report is used.


Description

PURPOSE

This parameter is the purpose of using the Event A2 per cell. It is used to activate the measurement gap as default. Mdt

ACTIVE_STATE

This parameter indicates whether event A2 is enabled/disabled per target frequency. This change will be applied to the UE from next RRC signaling procedure (e.g. Attach or Idle to Active). To avoid overload, a new setting will not be updated to the current active UEs. Inactive: Event A2 is not used. Active: Event A2 is used. If HO of the target frequency is not needed in the site, this is inactive.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MDTCTRL-PARA/RTRV-MDTCTRL-PARA Parameter

Description

IGNORE_MGMT_BASED_MDT_A LLOWED

According to the Specification, the Management Based MDT is allowed when Management Base MDT Allowed IE is included in the Initial Context Setup Request, X2 Handover Request, S1 Handover Request message. However, by this parameter the Management Based MDT can be allowed even if Management Base MDT Allowed IE is not included in the message. False: Allow to the case where the management Base MDT Allowed IE is included. True: Allow to the case where the management Base MDT Allowed IE


763


Description is not included.

UE_SELECTION_METHOD

This parameter represents the UE selection method in which it considers the UE Release version and location capability When selecting the management Based MDT Object UE. allRelease: Do all terminals with the selection object regardless of Release. aboveRelease10: Do the terminal that is the Release 10 or greater, with the selection object. aboveRelease10WithLocationInfoCapable: Do the terminal which is the Release 10 or greater and in which the supplying of location information is possible with the selection object.

RADIO_RESOURCE_USAGE_TH RESHOLD

This parameter represents the threshold regarding the radio resource amount used when selecting the Immediate Based MDT object UE. It does not select as MDT perform object UE if the load of MDT subject cell is this value or greater.

MDT_UE_PICKUP_RATE

This parameter represents the selection rate which is used when selecting the Management Based MDT object UE. If the random number generated between 0 is this value or less, select as MDT object UE.

RETRIEVE_LOGGED_MDT_REC ONFIGURATION_ALLOWED

This parameter represents whether to execute the UE Information process in case the logMeasAvailable is instructed in the RRC Connection Reconfiguration Complete message. False: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Reconfiguration Complete message is not allowed. True: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Reconfiguration Complete message is allowed.

RETRIEVE_LOGGED_MDT_REE STABLISH_ALLOWED

This parameter represents whether to execute UE Information process in case the logMeasAvailable is instructed in the RRC Connection Reestablishment Complete message. False: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Reestablishment Complete message is not allowed. True: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Reestablishment Complete message is allowed.

RETRIEVE_LOGGED_MDT_SETU P_ALLOWED

This parameter represents whether to execute UE Information process in case the logMeasAvailable is instructed in the RRC Connection Setup Complete message. False: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Setup Complete message is not allowed. True: the UE Information procedure due to the logMeasAvailable instruction of the RRC Connection Setup Complete message is allowed.

MAX_IMMEDIATE_MDT_UE_COU NT

This parameter represents the object terminal count permitted at the Management Based Immediate MDT. Allow on the terminal Immediate MDT measurement configuration setting up within this parameter setting value.

MAX_LOGGED_MDT_UE_COUNT

This parameter represents the number of terminals which can be setup for the Management Based MDT while considering the system load. This does not include the Logged MDT object terminal selection from new calls.


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REFERENCE [1] 3GPP 37.320: UTRA and E-UTRA; Radio measurement collection for Minimization of Drive Tests (MDT); Overall description; Stage 2 (Release 10) [2] 3GPP 36.300: E-UTRA and E-UTRAN; overall description Stage 2 (Release 10) [3] 3GPP 36.331: E-UTRAN; Radio Resource Control (RRC); Protocol specification (Release 10) [4] 3GPP 36.413: E-UTRAN; S1 Application Protocol (S1AP) (Release 10) [5] 3GPP 36.423: E-UTRAN; X2 Application Protocol (X2AP) (Release 10) [6] 3GPP 32.421: Telecommunication management; Subscriber and equipment trace; Trace concepts and requirements (Release 10) [7] 3GPP 32.422: Telecommunication management; Subscriber and equipment trace; Trace control and configuration management (Release 10) [8] 3GPP 32.423: Telecommunication management; Subscriber and equipment trace; Trace data definition and management (Release 10)


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LTE-SV0105, eMPS (Enhancements for Multimedia Priority Service) Support INTRODUCTION The Multimedia Priority Service (MPS) is introduced for supporting end-to-end priority treatment in call/session origination/termination. Enhancements for MPS include admission control and pre-emption for high priority calls and CSFB high priority call handling.

BENEFIT Operator can provide end-to-end priority treatment for high priority subscribers.

DEPENDENCY AND LIMITATION Dependancy The feature needs IOT with commercial UE, which supports high-priority access, and MME, which supports paging priority.

FEATURE DESCRIPTION This feature is introduced to provide a subscriber priority access to the system resources during congestion state. It includes three functions: paging priority, high-priority access, and preemption. UE requests a RRC connection with highPriorityAccess, and eNB processes this call with the same high priority as an emergency call. If the resource is not available, eNB preempts an existing call to accept the high priority call. For UE terminated call, eNB provides the paging priority. In congestion state, eNB can receive a huge number of pagine messages from MME. If a paging message is marked as a priority, eNB puts this message in front of the normal paging messages in the list. So, the message can be broadcasted in the very next paging occasion. eNB supports two level of paging priority: high or normal. For CSFB priority call handling, this paging priority must be supported. During E-RAB setup procedures, a high-priority ARP bearer can preempt an existing low-priority bearer in congestion.


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SYSTEM OPERATION How to Active Execute the command CHG-ENB-CAC to set the HIGH_PRIORITY_ACCESS_TYPE parameter to emergencyType, for handling the access call as an emergency.

Execute the command CHG-ENB-CAC to set the HIGH_PRIORITY_ACCESS_TYPE parameter to normalType, for handling the access call as a normal.

Key Parameters CHG-ENB-CAC/RTRV-ENB-CAC Parameter

Description

HIGH_PRIORITY_ACCESS _TYPE

This parameter determines the type of a highpriority access call. If the type is normalType, handles the highpriorityaccess as a normal call. When the type is emergencyType, handles the highpriorityaccess as an emergency call.


REFERENCE [1] 3GPP TS 36.331, Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC) protocol specification (Rel. 10) [2] 3GPP TS 36.413, Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP) (Rel. 10) [3] 3GPP TS 23.272, Circuit Switched Fallback in Evolved Packet System (Rel. 10)


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LTE-SV0202, ETWS (Earthquake and Tsunami Warning System) INTRODUCTION Earthquake and Tsunami Warning System (ETWS) is a public warning system to notify either earthquake or tsunami event. ETWS warning notification can be a primary, short notification delivered within 4 seconds, or secondary, providing detailed information.

BENEFIT Operator can provide public warning notifications to subscribers while they are connected in E-UTRAN.

Users can be notified by the public warning messages to avoid from disasters or accidents.

DEPENDENCY AND LIMITATION Dependency ETWS capable device is required.

In addition to EPC that supports ETWS, CBC is required.

FEATURE DESCRIPTION When an eNB receives the ETWS warning notification from an MME, it uses SIB 10 for primary notification and SIB11 for secondary notification. SIB10 and SIB11 can occur at any time, and the presence of an ETWS warning notification is informed by the paging message. If UE receives the paging message including the etws-Indication, it starts receiving the ETWS primary or secondary notification. Figure below illustrates the overall operation of the ETWS public alarm system.


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The ETWS warning notification transmission procedures are depicted in the figure below.


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The following are the message flows indicated in the figure above:

1 The CBE, for example, information source such as PSAP or Regulator, sends the emergency information, warning type, warning message, impacted area, and time period to the CBC.

2 Using the impacted area information, the CBC identifies the MMEs to be contacted and determines the information to be place into the Warning Area Information Element. Then, the CBC sends a Write-Replace Warning Request message containing the warning message to be broadcasted and the delivery attributes to MMEs. The attributes are message identifier, serial number, tracking area list, warning area, and so on.

3 The MME sends a Write-Replace Warning Response message to indicate the CBC that it has started to distribute the warning message to eNBs. Then, the CBC confirms to the CBE.

4 The MME forwards the Write-Replace Warning Request message to eNBs. The MME uses the tracking area list to determine the eNBs in the delivery area. If this list is empty, the message is forwarded to all eNBs that are connected to the MME.

5 On receiving the Write-Replace Warning Request message from the MME, eNB checks the message identifier and serial number fields within the warning message for duplicate detection. If any redundant messages are detected, only the first one received is broadcasted by the cells. The eNBs sends the WriteReplace Warning Response message to the MME, even if the message is redundant.

6 The eNB uses the Warning Area information to determine the cells in which the message is to be broadcasted. It broadcasts the message frequently according to the attributes set by the CBC that originated the Warning Message distribution. During ETWS warning notification, the eNB also indicates ETWS warning notification by paging. oSIB10 is used to transmit the ETWS primary notification. This notification includes the message identifier, serial number, warning type, and warning security information, which are received in the S1 Write-Replace Warning message. oSIB11 is used to transmit the ETWS secondary notification. This notification includes the message identifier, serial number, warning type, warning message contents (warning message segment), and data coding scheme, which are received in the S1 Write-Replace Warning message. The ETWS secondary notification can be transmitted in partition. The warning message segment type and number are included in the SIB11, as the information indicating partitioned transmission.

SYSTEM OPERATION How to Activate Execute the command CHG-SIB-INF to set the enumSibPeriodcity_type to not_used = 7, for deactivating this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Execute the command CHG-SIB-INF to change SIB transmit period. Key Parameters CHG-SIB-INF/RTRV-SIB-INF Parameter

Description

CELL_NUM


SIB2_PERIOD

This parameter is the broadcast interval for SIB2. not_used: Does not broadcast SIB2.

SIB3_PERIOD


SIB4_PERIOD


SIB5_PERIOD


SIB6_PERIOD


SIB7_PERIOD


SIB8_PERIOD


SIB9_PERIOD


SIB10_PERIOD


SIB11_PERIOD


SIB12_PERIOD


SI_WINDOW

This parameter is the SI window size. Each SI message is related to one SIwindow and not overlapped with the SI-windows of other SI messages. That is, one SI is broadcasted to one SI window. The length of SI-window is the same throughout all SI messages. A corresponding SI message within the SI-window is repeatedly broadcasted.


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[3] 3GPP TS36.413 Evolved Universal Terrestrial Access Network (E-UTRAN); S1 Application Protocol (S1AP)


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LTE-SV0301, A-GNSS (LPP) INTRODUCTION This feature expedites the GNSS signal acquisition process. The E-SMLC provides the Assistance Data namely A-GNSS to the UE, so that the GNSS receiver can speed up the acquisition process.

BENEFIT Operator can provide location-based services to subscribers with a faster positioning feature.

User can perform faster positioning and save battery power.

DEPENDENCY AND LIMITATION Dependency Supported by Release9 UE.

Supported by UE with the GNSS receiver. IOT with E-SMLC and UE is required.

FEATURE DESCRIPTION GNSS refers to various satellite systems, such as Global Positioning System (GPS) and Global Orbiting Navigation Satellite System (GLONASS). The traditional standalone GNSS receiver in the mobile device is responsible for receiving GNSS signals and estimating its position. The receiver acquires the GNSS signals through a search process, which can take more time. For example, if the UE is in indoor area or surrounded by tall buildings, it takes long time to search satellites or even fails to detect the satellite signal. The LTE positioning protocol is used for the delivery of the Assistance Data between the E-SMLC and UE. The E-SMLC sends the Assistance Data to the UE by LPP messages, so that the GNSS receiver can acquire the GNSS signal faster. These messages are carried as transparent PDUs across the intermediate network interfaces using the protocols, for example, S1-AP over the S1-MME interface and NAS/RRC over the Uu interface. The Assistance Data can be one or more of the followings:

Acquisition. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Sensitivity. Difference correction.

SYSTEM OPERATION How to Activate Activation procedure is not applicable because the LPP protocol is transparent to the eNB.



REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.305 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE Positioning Protocol (LPP)


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LTE-SV0302, Enhanced Cell ID INTRODUCTION This feature improves the accuracy in location estimation compared to the traditional Cell ID method in 3G networks. The Enhanced Cell ID (E-CID) method utilizes the following additional measurements information to improve the accuracy: UE Measurements

RSRP: Reference Signal Received Power RSRQ: Reference Signal Received Quality UE Rx-Tx time difference eNB Measurements

eNB Rx-Tx time difference Timing Advance Angle of Arrival

BENEFIT Operator can improve the accuracy of location based services. Users can enjoy more accurate location based services such as maps and navigations.

DEPENDENCY Required Network Elements MME, E-SMLC


Others The interaction between eNB and E-SMLC is based on LPPa protocol

LIMITATION External E-SMLC server is needed.


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FEATURE DESCRIPTION Samsung's enhanced cell ID positioning method complies with the method defined in 3GPP 36.305, which is LPPa based UL E-CID method. Downlink E-CID method is LPP based and transparent to eNB and is out of scope of this feature. This feature support on demand and periodic E-CID method, the following figure shows the call flow for E-CID positioning method.


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The following LPPa messages are used to exchange information between eNB and E-SMLC.

E-CID Measurement Initiation Request/Response/Failure E-CID Measurement Report E-CID Measurement Failure Indication/Termination


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The E-CID measurement initiation function is a procedure that the E-SMLC requests the E-CID measurement result from the eNB to calculate the position of the UE. The eNB operates as follows depending on the contents of the E-CID measurement initiation request message transmitted by the E-SMLC.

If the value of the report characteristics is 'on demand': Transmits the E-CID MEASUREMENT INITIATION RESPONSE message (and the measurement result) including the requested value.

If the value of the report characteristics is 'periodic': Starts the periodic report timer and transmits the E-CID MEASUREMENT INITIATION RESPONSE message (excluding the measurement result). Then transmits the periodic ECID measurement report to the E-SMLC. eNB support configuration of following measurement in serving cell:

Angle of Arrival (AoA) (supported values 0 or 120 or 240 with resolution of 120 degree)

Timing Advance type 1 and 2 RSRP RSRQ eNB support the following measurements in neighbour cells

RSRP RSRQ The above serving cell and neighbour cells(SLR 5.0) measurements will be forward to E-SMLC for position calculation. eNB enhanced eNB rx-tx time difference measurement in SLR 6.0. Higher resolution for eNB Rx-Tx time difference can be supported, so more accurate TA1 measurement can be supported in SLR 6.0, where eNB Rx-Tx time difference can have a minimum resolution of 2Ts. Samsung also provide a scheme to support pre-rel 9 UE TA1 measurement in SLR 6.0. As pre-rel9 UE does not support UE Rx-Tx time difference measurement, Samsung eNB support to measure the TA1 based on both Timing Advance during Random Access procedure(also called TA2) and Timing Advance command sent by MAC Control Element(considered as TA offset). Therefore the TA1 measurement resolution for pre-rel9 UE is 16Ts.




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Key Parameters Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-POS-CONF/RTRV-POS-CONF Parameter

Description

CELL_NUM


LATITUDE

The latitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the latitude value.

LONGITUDE

The longitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the longitude value.

HEIGHT

The altitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the altitude value.

UNCERTAINTY_SEMI_MAJ OR

The uncertainty of semi major. The uncertainty, which the user enters directly. It can be calculated by a formula of r = 10 * (1.1 k - 1).

UNCERTAINTY_SEMI_MIN OR

The uncertainty of semi minor. The uncertainty, which the user enters directly. It can be calculated by a formula of r = 10 * (1.1 k - 1).

ORIENTATION_OF_MAJOR _ AXIS

The orientation of the major axis, which the user directly enters the value chosen from 0 to 179.

UNCERTAINTY_ALTITUDE

The uncertainty of altitude tolerance, which the user enters directly. It can be calculated by using a formula of h = 45 * (1.025 k - 1).

CONFIDENCE

The confidence (%) of location service.

PRS_CONFIG_INDEX

PRS configuration index. If the user enters a value, eNB sends the value to MAC layer.

NUM_OF_DL_FRAME

The number of downlink frames. If the user enters a value, eNB sends the value to MAC layer.

PRS_MUTING_CONFIG_SI ZE

PRS muting configuration size. If the user enters a value, eNB sends the value to MAC layer.

PRS_MUTING_CONFIG_V ALUE

PRS muting configuration. If the user enters a value, eNB sends the value to MAC layer.

PRS_BANDWIDTH

PRS Bandwidth. If the user enters a value, eNB sends the value to MAC layer.

OTDOA_ENABLE

OTDOA function On/Off. If this parameter set False, OTDOA service is off and also PRS signaling is off.



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[2] 3GPP TS36.455 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE Positioning Protocol A (LPPa) [3] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [4] 3GPP TS 36.305 Evolved Universal Terrestrial Radio Access Network (EUTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN [5] 3GPP TS 36.355 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE Positioning Protocol (LPP) [6] 3GPP TS 36.133 Evolved Universal Terrestrial Radio Access (E-UTRA); Requirements for support of radio resource management


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LTE-SV0303, OTDOA INTRODUCTION In the Observed Time Difference of Arrival (OTDOA) positioning feature, the UE makes an observation of the time difference of arrival of the Reference Signal (RS) from two or more eNBs. The position of the UE can be calculated based on the known position of the eNBs and the time differences.

BENEFIT Operator can provide an OTDOA-based location service. End-users can enjoy more accurate location-based services such as maps and navigations.

DEPENDENCY AND LIMITATION Dependency UE that supports OTDOA based on 3GPP Release 9 or later version.

MME to support LPPa protocol. E-SMLC to support OTDOA. eNB that supports PRS. Precise synchronization between eNBs is required for better accuracy, GPS synchronization is recommended.

SFN must be synchronized between eNBs. Limitation Air interface throughput is impacted due to the PRS broadcasting, as there is no PDSCH data in the sub-frame where PRS is located.

In rural areas, there are fewer measureable cells that can impact accuracy. PRS sub-frame configuration needs to be manually planned to ensure no overlapping with PBCH, SIBs, paging, and measurement gap scheduling.

No SON functionality is available to support automatic PRS configuration. The PRS configurations will have to be manually planned and configured.


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FEATURE DESCRIPTION The time difference between the RS from the serving and neighbor cells is called Reference Signal Time Difference (RSTD). To measure the RS from neighbor cells, a special positioning signal is defined in Release 9 namely Positioning Reference Signal (PRS). PRS is introduced to improve the hearability of neighboring cells within completing measurements for the downlink OTDOA positioning method. 3GPP recognized that the hearability of the existing cell-specific reference signals was not sufficient to support the OTDOA positioning method. Hearability can be challenging as a result of the neighboring cells being co-channel with the serving cell, especially at locations where the serving cell signal strength is high. For E-SMLC, the UE provides RSTD information through the LPP protocol layer and the eNB provides PRS and base station information through the LPPa protocol layer. Then, E-SMLC makes a final decision on the position of the UE. MME transparently relays the LPP and LPPa layer information to E-SMLC. The OTDOA positioning method makes use of Reference Signal Time Difference (RSTD) measurements from the UE. The RSTD quantifies the sub-frame timing difference between a reference and neighboring cells. The accuracy of the positioning calculation is improved if the UE can provide RSTD measurements from an increased number of cells. RSTD is measured in units of Ts (1/30720 ms) and is reported to the Enhanced Serving Mobile Location Center (E-SMLC) where the location calculation is completed. The UE receives an LTE Positioning Protocol (LPP) Provide Assistance Data message from E-SMLC. This message is packaged by MME as a NAS message before being packaged by eNB as an RRC message. The Provide Assistance Data message includes information for both the reference and neighboring cells. The reference cell does not have to be the current serving cell for the UE. Positioning reference signals (PRS) are able to coexist with both the cells specific reference signals and the physical layer control information at the start of each sub-frame (PCFICH, PHICH, and PDCCH). It occupies an increased number of resource elements within a sub-frame relative to the cell specific reference signals to improve RSTD measurement accuracy. The Physical Cell Identity (PCI) generates the sequence for the positioning reference signal and the cyclic prefix duration, normal or extended. The PRSs are broadcasted using the antenna port 6. They are not mapped onto the resource elements allocated to the PBCH, primary synchronization signal nor secondary synchronization signal. The PRSs are only defined for the 15 kHz subcarrier spacing. They are not supported for the 7.5 kHz subcarrier spacing used by the Multimedia Broadcast Multicast Services (MBMS). Figure below illustrates examples of the positioning reference signal for normal cyclic prefix. There is a dependency upon the number of antenna ports used for the cell specific reference signal. Additional symbols are used by the cell specific reference signal when broadcasting from four antenna ports. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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The PRS configuration parameters include:

PRS Bandwidth: The bandwidth that PRS occupies. The positioning reference signal bandwidth is signalled to the UE with 6, 15, 25, 50, 75, or 100 resource blocks. The positioning reference signal bandwidth is always centered on the middle of the channel bandwidth. The positioning reference signal configuration index is used to define both a periodicity and sub-frame offset for the timing of the positioning reference signal. The look-up table presented below is used to link the configuration index to the periodicity and sub-frame offset. PRS Configuration Index: This parameter defines the periodicity (TPRS) and sub-frame offset (ΔPRS) for the timing of the PRS. Table below shows the relation among these parameters.

Number of Consecutive Downlink Sub-frames: This parameter defines the number of sub-frames during which the positioning reference signal is broadcast within each positioning reference signal period. It can be configured with 1, 2, 4, or 6 sub-frames.

PRS Muting Configuration: This parameter consists of 2, 4, 8, or 16 bit map sequence. The periodicity of the muting pattern is defined by the length of the bit map. The PRS positioning occasion does not exist in the sub-frame if the corresponding bit is set to 0.


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Based on 3GPP 36.211, PRS is not transmitted in RE allocated to PBCH, PSS, and SSS. The UE only uses PRS except resources allocated to PBCH, PSS, and PSS, SSS. PBCH and synchronization signal are transmitted in sub-frame #0 and bandwidth (6RB). When the resources are allocated,, PRS can be transmitted to only 38 % (FDD) or 50 % (TDD) among total REs available for PRS allocation. Therefore, to set the PRS configuration index in PLD, it is recommended to operate without transmitting PRS in subframe #0. To allocate PDSCH and PRS to the same RB, it needs to determine PDSCH in RE to where PRS is transmitted. This can cause performance decrease of PDSCH reception and PRS reception of neighbor cell. Therefore, the eNB does not transmit PDSCH in RBs where PRS is allocated. In case of paging and SIB1 transmitted to a fixed sub-frame, it is considered that there is no PRS when UE decodes the corresponding traffic. Therefore, if one of either paging/SIB1 or PRS needs to determine the other, the reception performance of paging/SIB1 or PRS decreases. It is recommended to operate without transmitting PRS in subframe (= 5, 9) to where paging/SIB1 is transmitted, when setting up the PRS configuration index. The eNB interworks with E-SMLC with LPPa interface. OTDOA Information Exchange procedure is used to allow the E-SMLC request the eNB to transfer OTDOA information to the E-SMLC. The procedure consists of the following messages:

OTDOA Information Request/Response/Failure After the eNB receives the OTDOA information request message from the ESMLC, the OTDOA information transfer function is performed as follows: oIf the eNB receives the OTDOA cell information, it transmits the OTDOA INFORMATION RESPONSE message including the cell information. oIf the eNB fails to receive the OTDOA cell information, it transmits the OTDOA INFORMATION FAILURE message including the failure cause. The followings are the OTDOA cell information:

PCI Cell ID TAC EARFCN PRS Bandwidth PRS Configuration Index CP Length Number of DL Frames Number of Antenna Ports SFN Initialization Time E-UTRAN Access Point Position eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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PRS Muting Configuration To implement the RSTD measurement, the UE receives an LPP Provide Assistance Data message from the E-SMLC. This message is packaged by the MME as a NAS message before being packaged by the eNB as an RRC message. The Provide Assistance Data message includes information for both the reference and neighboring cells. The content of the reference cell information is presented in table below. Information Element physCellId cellGlobalId earfcnRef antennaPortConfig cpLength prsInfo

prs-Bandwidth prs-ConfigurationIndex numDL-Frames prs-MutingInfo

After receive the OTDOA Assistance Data, the UE starts the RSTD measurement and reports the measurement results to E-SMLC through LPP interface where the location calculation is completed.

Measurement gap exclusion To ensure UE can perform RSTD measurement, measurement gap is not scheduled in the sub-frames where PRS is located. Otherwise, the RSTD measurement can fail when the UE performs the inter-FA/RAT measurement. The eNB supports excluding of specified measurement gap offsets. The excluded gap offset is configurable, to ensure all UEs receive PRS. The excluded offset can be one or combination of offsets. The measurement gap offset exclusion can be enabled or disabled. You can configure the starting offset and rang of consecutive gap offset. Starting gap offset range is 0 to 39 or 0 to 79 considering of gap pattern. While rang of consecutive gap offset number can be 1 to 15. For example, if the starting offset is set to 0 and offset range is set to 15, then the gap offset 0 to 14 are excluded.

Inter-frequency RSTD measurement support (SLR4.5) In OTDOA positioning method, especially in the inter frequency cell deployment, E-SMLC can request the UE to perform the inter-frequency RSTD measurement. This improves the accuracy by obtaining more RSTD measurement results. This feature enables the eNB to start or stop the requested measurement gap sent from the UE. To do this, new Release 10 RRC procedures Inter-frequency RSTD measurement indication and Inter-frequency RSTD measurement indication are introduced. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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After the eNB receives the requested measurement gap from UE, it can start to configure the gap or ignore the request if the requested gap is not acceptable set in the system. Currently, three options are provided to control eNB action when the RSTD measurement indication message is received:

Ignore: When the eNB ignores the UE request, the measurement gap will not be assigned. This limits the impact to current UE performance, as measurement gap can impact the performance.

Accept: The eNB always accepts the UE request. This ensures that the UE receives the inter-frequency RSTD measurement for better accuracy of LCS.

Measurement gap algorithms based: In this option, if the UE request can be accepted by the current measurement gap allocation algorithms, then the gap is allocated to the UE. If the request cannot be accepted, then the requested gap is ignored.

Operator Configurable PRS Power Boosting This feature supports the PRS power boosting with average maximum power. To ensure better RSTD measurement performance, PRS power is configured with a larger power. The configurable range is from 0 dB to 7.75 dB by 0.5 dB step.

SYSTEM OPERATION How to Activate Execute the command CHG-POS-CONF to set the OTDOA_ENABLE parameter to 1 (True), for activating the OTDOA function.

Execute the command CHG-POS-CONF to set the MEAS_GAP_OFFSET_EXCLUDED parameter to True, for activating the measurement gap exclusion function.

Execute the command CHG-POS-CONF to set the PRS_POWER_BOOST_OFFSET parameter to the value greater than 0, for activating the PRS power boost function.

Execute the command CHG-MSGAP-INF to set the RSTD_MEAS_GAP_OPTION parameter to AlwaysAccept or ByAlgorithm, for activating the inter-frequency RSTD measurement gap assignment function.

Key Parameters RTRV-POS-CONF/CHG-POS-CONF Parameter

Description

OTDOA_ENABLE

If the otdoaEnable value is set to 1 (On) to execute OTDOA included in the UE Positioning function, an eNB transmits a PRS signal and a UE transmits related configuration, and so on to the eNB. If the otdoaEnable value is set to 0 (Off), an eNB does not transmit PRS but transmits the information of the cell.

PRS_BANDWIDTH

The positioning reference signal (PRS) bandwidth value. If an operator enters


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Description this value, the eNB forwards the value to the MAC layer. Transmission bandwidth of PRS. Values from 0 to 5 are mapped with prsBw6_1.4 MH, prsBw6_1.4 MHz, prsBw15_3 MHz, prsBw25_5 MHz, prsBw50_10 MHz,

MEAS_GAP_OFFSET_EXC LUDED

This attribute represents that measurement gap offset exclusion function is activated or deactivated.

For inter-frequency RSTD measurement gap assignment function, RTRV-MSGAP-INF/CHG-MSGAP-INF Parameter

Description

RSTD_MEAS_GAP_OPTIO N

This parameter indicates the methods how to allocate MeasurementGap when eNB receives an InterFreqRSTDMeasurementIndication from UE.

For PRS power boost function, RTRV-POS-CONF/CHG-POS-CONF Parameter

Description

PRS_POWER_BOOST_OFFS This parameter is the PRS power boosting offset value. When the operator ET enters the value, the eNB transmits the value to the MAC layer.

RTRV-POS-CONF/CHG-POS-CONF Parameters

Description

CELL_NUM

The cell number. This value must not exceed the maximum number of cells supported by the system. It is determined by FA/Sector. For example, if the maximum capacity system is 1 FA/3 Sector, up to three cells are supported.

LATITUDE

The latitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the latitude value.

LONGITUDE

The longitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the longitude value.

HEIGHT

The altitude of the cell for providing the OTDOA function. The UE location information included in the cell can be calculated using the altitude value.

UNCERTAINTY_SEMI_MAJ OR

The uncertainty of semi major. The uncertainty, which the user enters directly. It can be calculated by a formula of r = 10 * (1.1 k - 1).

UNCERTAINTY_SEMI_MIN OR

The uncertainty of semi minor. The uncertainty, which the user enters directly. It can be calculated by a formula of r = 10 * (1.1 k - 1).

ORIENTATION_OF_MAJOR _AXIS

The orientation of the major axis, which the user directly enters the value chosen from 0 to 179.

UNCERTAINTY_ALTITUDE

The uncertainty of altitude tolerance, which the user enters directly. It can be calculated by using a formula of h = 45 * (1.025 k - 1).

CONFIDENCE

The confidence (%) of location service.

PRS_CONFIG_INDEX

PRS configuration index. If the user enters a value, eNB sends the value to MAC layer.

NUM_OF_DL_FRAME

The number of downlink frames. If the user enters a value, eNB sends the value to MAC layer.

PRS_MUTING_CONFIG_SI ZE

PRS muting configuration size. If the user enters a value, eNB sends the value to MAC layer.


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Description

PRS_MUTING_CONFIG_VA LUE

PRS muting configuration. If the user enters a value, eNB sends the value to MAC layer.

PRS_BANDWIDTH

PRS Bandwidth. If the user enters a value, eNB sends the value to MAC layer.

OTDOA_ENABLE

OTDOA function On/Off. If this parameter set False, OTDOA service is off and also PRS signaling is off.

PRS_POWER_BOOST_OF FSET

This parameter is the PRS power boosting offset value. When the operator enters the value, the eNB transmits the value to the MAC layer.

MEAS_GAP_OFFSET_EXC LUDED

This attrubute represents that measurement gap offset exclusion function is activated or deactivated.

For measurement gap exclusion function, RTRV-MGAPEXCLUDE-INF/CHG-MGAPEXCLUDE-INF Parameter

Description

GAP_PATTERN_ID

This attribute represents measurement gap identity (that is, 0 or 1).

GAP_START_OFFSET

This attribute represents start offset of measurement gap is/are excluded.

GAP_OFFSET_RANGE

This attribute represents offset range of measurement gap is/are excluded (for example, if gapStartOffset value is ‘0’ and gapOffsetRange value is ‘15’, excluding measurement gap offset from ‘0’ to ‘14’).


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.455 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE Positioning Protocol A (LPPa) [3] 3GPP TS 36.211 Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation [4] 3GPP TS 36.305 Evolved Universal Terrestrial Radio Access Network (EUTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN [5] 3GPP TS 36.355 Evolved Universal Terrestrial Radio Access (E-UTRA); LTE Positioning Protocol (LPP) [6] 3GPP TS 36.133 Evolved Universal Terrestrial Radio Access (E-UTRA); Requirements for support of radio resource management


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LTE-SV0401, Vocoder Rate Adaptation INTRODUCTION The eNB employs features to reduce the voice packet size, which are helpful to maximize capacity and/or coverage for VoLTE service, such as RoHC, RLC UM mode with 5 bit sequence number and PDCP 7 bit sequence number. In addition to that, the 3GPP defines adaptation mechanism by providing support of vocoder rate change in LTE networks. Based on load criteria (that is, cell congestion), the eNB marks Explicit Congestion Notification-Congestion Experienced (ECN-CE) codepoint within IP header of VoLTE packets (that is, PDCP SDUs). This enables the eNB to control ECN-triggered codec rate reduction at UE side. At peak hour, the eNB can get additional capacity in terms of VoLTE UEs in the cell at a tradeoff for some voice quality. Additionally, the eNB marks ECN-CE for the UE that is moved to the cell edge to maximize coverage regardless of congestion situation.

BENEFIT Operator can accommodate more VoLTE users in congestion situation and provide extended coverage.

Users can experience seamless VoLTE service quality.

DEPENDENCY None

LIMITATION The UE should support ECN-triggered adaptation.



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FEATURE DESCRIPTION ECN copying to deliver information of backhaul congestion.

Inner IP (ECN = '01'/'10')

ECN field copy

Payload

SAE-GW Outer IP (ECN = '01'/'10'

UDP

GTP

Inner IP (ECN = '01'/'10')

Payload

Congestion experienced SW/RT

Outer IP (ECN = '11')

UDP

GTP

Inner IP (ECN = '01'/'10')

Payload

eNB

ECN field copy Inner IP (ECN = '11')

Payload

Request code rate


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ECN marking for Codec Rate Adaptation

4

2

3

RTCP-APP-CMR or CMR in RTP payload

ECN: Explicit Congestion Notification ECT: ECN-Capable Transport CE: Congestion Experienced CMR: Codec Mode Request

Trigger condition

ECN-CE marked voice packet

1

5

ECN-ECT marked voice packet

Codec rate downgraded voice packet

1 The ECN capable UE sends voice packets with ECN-ECT marked in the IP header.

2 Trigger condition for ECN marking is satisfied. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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3 The eNB marks downlink voice packet with ECN-CE('11'). 4 If the UE receives ECN-CE marked voice packet, UE decides codec rate downgrade and requests codec mode change toward the peer UE via RTCP-APP-CMR or CMR in the RTP payload. (UE's functionality)

5 If the peer UE receives CMR, the UE changes codec rate in accordance with received CMR if available. (UE's functionality) Uplink ECN marking is similar operation as downlink ECN marking.

Trigger condition for ECN marking 1 Congestion of a cell If the congestion level exceed configured threshold, the eNB marks all voice packets with ECN-CE.

2 Mobility event (A2 with new purpose for Rate Adaptation) of a UE If the eNB receives a specific mobility event (A2) from the UE, the eNB marks voice packets for the target UE with ECN-CE. The number of packets to be marked is pre-configured.


How to Activate This section provides the information that you need to configure the feature. Preconditions This feature shall be work with UE which supports „rate adaptation‟ according to ECN field. Activation Procedure Run CHG-CELLECN-CTRL and set RATE_ADAPT_ENABLE to 1 to enable the ECN marking for this feature. (SET PRB_QCI_EABLE or MR_EVENT_ENABLE as 1) Deactivation Procedure Run CHG-CELLECN-CTRL and set RATE_ADAPT_ENABLE to 0 to disable the ECN marking.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature.


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Activation/Deactivation Parameter To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-CELLECN-CTRL/RTRB-CELLECN-CTRL Parameter

Description

PRB_UL_THRESHOLD

This parameter is uplink PRB threshold to check cell (uplink) congestion state. Value is displayed as (* 1000), and this value is just percentage threshold of PRB usage. 0~100000

PRB_DL_THRESHOLD

This parameter is uplink PRB threshold to check cell (downlink) congestion state. Value is displayed as (* 1000), and this value is just percentage threshold of PRB usage. 0~100000

Configuration Parameter To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-EUTRA-A1CNF(Q)/RTRV-EUTRAA1CNF(Q) Parameter

Description

PURPOSE

This parameter is the purpose of using Event A1 event. MeasGapDeact: Used to disable measurement gap and forwards A1 event reception measurement gap release information. CaPeriodicMr: For Periodic Measurement Report based Carrier Aggregation. CaInterFreq: For Inter-Frequency Carrier Aggregation. Ecn: used to MR for ECN marking/marking stop.

Parameter Descriptions of CHG-EUTRA-A2CNF(Q)/RTRV-EUTRAA2CNF(Q) Parameter

Description

PURPOSE

This parameter is the purpose of using the Event A2 per cell. It is used to activate the measurement gap as default. LteHo: Used for Gap Activate. LteBlind: Used for Blind HO. IRatHo: Used for IRAT HO. ... Ecn: used to MR for ECN marking/marking stop.



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REFERENCE [1] 3GPP TR 23.860 Enabling Coder Selection and Rate Adaptation for UTRAN and E-UTRAN for Load Adaptive Applications; Stage 2 [2] 3GPP TS 26.114 IP Multimedia Subsystem (IMS); Multimedia Telephony; Media handling and interaction [3] 3GPP TS 36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [4] 3GPP TS 23.401 General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access [5] IETF RFC 3168-The Addition of Explicit Congestion Notification (ECN) to IP [6] IETF RFC 6679-Explicit Congestion Notification (ECN) for RTP over UDP


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LTE-SV0404, VoLTE Quality Enhancement INTRODUCTION VoLTE traffic is characterized by periodic small sized packets. The QCI value 1 and RLC UM mode Guaranteed Bit Rate (GBR) bearers are used for carrying the VoLTE traffic. The VoLTE Quality Enhancement feature is enabled based on the QCI of the bearer.

BENEFIT The voice quality reduction related to RTP loss and delay, which are used as VoLTE service quality indicators by operator, is enhanced.

Operator can identify the VoLTE related counters. User experienced VoLTE service is enhanced by reducing packet loss or preventing silence period during VoLTE session calls.

DEPENDENCY AND LIMITATION Limitation DL cell throughput is impacted due to conservative RB allocation for VoLTE user HARQ re-transmissions.

UL cell throughput is impacted due to VoLTE-aware UL grant in case of SID period of a VoLTE session.

Downlink packet mirroring causes duplicate packets to be delivered to application layer (RTP).

FEATURE DESCRIPTION The user perceived quality of VoLTE service is determined by several parameters such as packet delay/jitter and packet loss. The following functions are implemented to enhance the user observed quality of VoLTE service:

VoLTE-aware UL Grant. Configuration of Target BLER for VoLTE. Conservative RB Allocation for VoLTE. Reduction of UL Packet loss at Source eNB during Handover. Reduction of DL Packet Loss at Source eNB during Handover. VoLTE related Counters.


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VoLTE-aware UL Grant In VoLTE, the packets are divided into small size and transmitted over the network periodically. For example, 60 byte packets in every 20 ms. The UE sends the Buffer Status Report (BSR) MAC control element periodically to eNB to obtain the uplink grant for sending these small sized data packets. In some scenarios, listed below, the UE has data available for transmission, however, the data cannot be sent:

UE transmits BSR along with VoLTE packet and the MAC PDU fails to receive at eNB side even after maximum HARQ re-transmission attempts.

UE transmits a non-zero BSR after transmission of a zero BSR. The BSR can be received at eNB side in reverse order, if the zero BSR transmitted encounters more HARQ re-transmissions. Both of these scenarios result in no UL grant allocation for the UE. Therefore, data cannot be transmitted for hundreds of milliseconds. This causes silence periods during a VoLTE call. The VoLTE-aware UL Grant function allocates dummy UL grants to UE even if the uplink buffer status of the UE is calculated as zero. The UL scheduler allocates uplink grant based on the recent non-zero BSR of the UE, when:

The internal buffer occupancy of a UE is calculated as zero after 32 ms. Receiving zero BSR from a UE after 32 ms. This can reduce the overall UL resource, however, enhances VoLTE service quality in poor uplink radio coverage scenarios.

Configuration of Target BLER for VoLTE Unlike the non-GBR bearer services that demands high spectral efficiency due to high throughput, VoLTE bearer requires low spectral efficiency, as VoLTE demands very less throughput. However, the VoLTE bearer is delay sensitive. This function sets the target BLER lower than the conventional services to reduce downlink and uplink packets transmission error rate. As the throughput requirements are low, MCS is allocated conservatively to improve the HARQ error rate and to meet the target BLER. UE Type

UL Target BLER

DL Target BLER

VoLTE

2.7 %

2.5 %

Non VoLTE

10 %

10 %

Conservative RB Allocation for VoLTE To prevent VoLTE service quality deterioration in a poor radio condition, this function allocates downlink resources conservatively to reduce the HARQ error rate and BLER. If the initial transmission and the first re-transmission of a VoLTE MAC PDU fail, the DL scheduler allocates eight times more resource blocks than the initial transmission for second re-transmission. If the increased resource block count is eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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greater than the maximum PDSCH RB allocation limit, the maximum possible RBs are allocated. For increased RB allocation, MCS is maintained same as previous transmission, and hence code-rate of this re-transmission reduces considerably. Reduced code rate improves the HARQ error rate.

Reduction of UL Packet Loss at Source eNB during Handover During handover procedure, the eNB RLC performs RLC re-establishment as soon as the RRC layer creates and sends Handover Command message to the lower layer. The RLC buffer clears, stops the timers, and resets the RLC state variables. During this time, any UL packets arrive at eNB are lost. The handover command can take a while to reach to the UE by HARQ/ARQ retransmissions. In this case, the UE continue sending the UL packets until it receive the handover command. These packets are lost at eNB. To prevent the packet loss during handover, the eNB does not perform RLC reestablishment when handover command is sent to UE. The eNB performs the following functions:

In case of UL, the packet remaining in the RLC re-ordering buffer is not discarded after transmitting handover command. However, the packet from MAC is assembled and transmitted to S-GW.

In case of DL, the packet remaining in the RLC buffer is not discarded, however, transmitted to the UE. This function reduces the chance of packet loss of VoLTE service during handover.


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Reduction of DL Packet Loss at Source eNB during Handover Loss of VoLTE packets during handover degrades the VoLTE quality. As QCI 1 bearers are serviced by RLC UM mode, DL VoLTE packets to be transmitted and scheduled in RLC buffer are cleared when the handover command is sent to the UE. To prevent further reduce in DL packet loss during handover, the eNB mirrors one DL VoLTE packet (QCI 1) in PDCP layer. During handover, the source eNB forwards the mirrored VoLTE packets to the target eNB. The target eNB sends the packet to UE for minimizing the packet loss. Figure below depicts the detailed operation of this function.

When the eNB receives the VoLTE packet from S-GW, the packet is copied and saved in the mirroring buffer in the PDCP layer before processing RoHC and ciphering functions.

The VoLTE packet is transmitted to RLC after processing RoHC and ciphering functions.

Mirroring buffer saves one VoLTE packet. If mirroring buffer already contains a packet, the older packet is deleted and the new packet is saved.

If the handover command (RRC connection reconfiguration) is transmitted from the source eNB, the saved packet is transmitted to the target eNB.


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VoLTE related counters Table below lists the newly introduced VoLTE related counters and their description. VoLTE related Counter

Description

VoLTE call drop rate

Statistics on the rate of dropped VoLTE calls among all VoLTE calls.

VoLTE intra/S1/X2 handover success rate

Statistics on the rate of VoLTE calls with intra/S1/X2 handover success among VoLTE calls with intra/S1/X2 handover attempt respectively.

VoLTE handover latency time

Statistics on the Min/Max/Avg latency time collected from target eNodeB during handover.

VoLTE quality defect rate for DL/UL VoLTE bearer

Statistics on the rate of DL/UL VoLTE bearers respectively with at least one occurrence of packet interval greater than threshold (for example, 1 s) among all VoLTE bearers.

HARQ failure rate for DL/UL VoLTE bearer

Statistics on the rate of VoLTE packets with HARQ failure among all VoLTE packets for DL/UL VoLTE bearers respectively.

CQI for DL VoLTE bearer

Statistics on the CQI report information for DL VoLTE bearers

Distribution of SINR for UL VoLTE bearer

Statistics on the SINR distribution regarding to the before and after Outer-loop compensation for UL VoLTE bearers.

SYSTEM OPERATION How to Activate This feature is basically enabled and the operator cannot disable.



Type Name

Type Description

VoLTE Quality Defect

VoLTE_UlQualityDefect

The number of QCI #1 bearers which has no RTP interval during specific amount of time for UL VoLTE packet.

VoLTE_DlQualityDefect

The number of QCI #1 bearers that has no RTP interval during specific amount of time for DL VoLTE packet.

VoLTE_IntraEnbAtt

Intra-handover attempt count.

VoLTE_IntraEnbPrepSucc

Successful intra-handover preparation count.

VoLTE_IntraEnbSucc

Successful intra-handover execution count.

VoLTE_InterX2OutAtt

X2 handover attempt count

VoLTE_InterX2OutPrepSucc

Successful X2 handover preparation count.

VoLTE_InterX2OutSucc

Successful X2 handover execution count.

VoLTE_InterS1OutAtt

S1 handover attempt count.

VoLTE Handover


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VoLTE Ho Time

VoLTE Quality

Type Name

Type Description

VoLTE_InterS1OutPrepSucc

Successful S1 handover preparation count.

VoLTE_InterS1OutSucc

Successful S1 handover execution count.

VoLTE_IntraHoTime_Avg

When intra-eNB handover is completed, this statistic is collected.

VoLTE_IntraHoTime_Min

This counter is updated when VoLTE_IntraHoTime_Avg is collected and it is low than previous maximum value.

VoLTE_IntraHoTime_Max

This counter is updated when VoLTE_IntraHoTime_Avg is collected and it is greater than previous maximum value.

VoLTE_IntraHoTime_Cnt

This counter is cumulated when VoLTE_IntraHoTime_Avg is collected.

VoLTE_IntraHoTime_Tot

This counter is cumulated when VoLTE_IntraHoTime_Avg is collected.

VoLTE_X2HoTime_Avg

When X2 handover is completed, this statistic is collected.

VoLTE_X2HoTime_Min

This counter is updated when VoLTE_X2HoTime_Avg is collected and it is greater than previous maximum value.

VoLTE_X2HoTime_Max

This counter is cumulated when VoLTE_X2HoTime_Avg is collected.

VoLTE_X2HoTime_Cnt


VoLTE_X2HoTime_Tot


VoLTE_S1HoTime_Avg

When S1 handover is completed, this statistic is collected.

VoLTE_S1HoTime_Min

This counter is updated when VoLTE_S1HoTime_Avg is collected and it is greater than previous maximum value.

VoLTE_S1HoTime_Max

This counter is cumulated when VoLTE_S1HoTime_Avg is collected.

VoLTE_S1HoTime_Cnt


VoLTE_S1HoTime_Tot


VoLTE_DropRate

The number of VoLTE drop rate.

VoLTE_UlQualityDefectRate

The number of UL quality defect rate.

VoLTE_DlQualityDefectRate

The number of DL quality defect rate.

VoLTE_IntraHoSuccessRate

The number of VoLTE HO intra success rate.

VoLTE_X2HoSuccessRate

The number of VoLTE HO X2 success rate.


800


Type Name

Type Description

VoLTE_S1HoSuccessRate

The number of VoLTE HO S1 success rate.

REFERENCE N/A


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LTE-SV0406, VoLTE Coverage Enhancement INTRODUCTION Until now, various techniques to improve LTE coverage have been introduced. Typical technique is sub-frame bundling (TTI bundling). However, current VoLTE coverage is usually worse than the voice coverage of 2G/3G. In order to provide voice coverage of LTE comparable to that of 2G/3G, VoLTE coverage enhancement is introduced.

BENEFIT Minimize the required number of eNB for network service provider Seamless voice quality for network subscriber

DEPENDENCY FDD: UE should support sub-frame bundling (TTI bundling) and PUSCH frequency hopping. This feature requires LTE-ME3307 UL Sub-frame Bundling and LTE-ME1503 PUSCH Frequency Hopping.

TDD: UE should supportPUSCH frequency hopping. This feature requires LTEME1503 PUSCH Frequency Hopping.

LIMITATION None


FEATURE DESCRIPTION VoLTE coverage enhancement is composed of the following tree component techniques.

VoLTE packet segmentation Reduces instantaneous bitrate by segmentation of voice-packet into multiple MAC PDUs

Increasing max HARQ re-transmission limit Provides robust coding gain by increasing maximum HARQ transmission

PUSCH frequency hopping eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Provides diversity gain in frequency selectie fading


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure To activate this feature, do the following: Run CHG-PUSCH-IDLE, and then set PUSCHhoppingEnabled as True. Deactivation Procedure To deactivate this feature, do the following: Run CHG-PUSCH-IDLE, and then set PUSCHhoppingEnabled as False.

Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-PUSCH-IDLE/RTRV-PUSCH-IDLE Parameter

Description

PUSCHhoppingEnabled

This parameter enable PUSCH frequency hopping 'True': Enabled 'False': Disabled

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-TRCH-INF/RTRV-TRCH-INF Parameter

Description

maxHARQTxBundling

Maximum number of UL HARQ transmission(including initial transmission) for sub-frame bundling mode (TTIB mode)


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Counters and KPIs Table below outlines the main Key Performance Indicators (KPIs) associated with this feature. Family Display Name

Type Name

Type Description

PDCP_LOSS

PdcpSduLossRateUL

Intra-eNB handover success rate of E-UTRAN mobility.

REFERENCE [1] 3GPP TS 36.321, Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification [2] 3GPP TS 36.213, Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures


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LTE-SV0501, eMBMS Basic Function INTRODUCTION The introduction of the Smart Phone allows individuals to watch video contents over the handheld devices more than ever before. The viewers are no longer being tethered by the cable TV. The mobile entertainment market is expected to continuously grow in the next years. However, the very nature of Unicast, inefficient bidirectional point to point transmission between the each of the users and the network, has made broadcasting video contents an efficient choice of delivery. The 4G, Long Term Evolution of UMTS is the latest development in an mobile telecommunications system, requires to support enhanced version of the Multimedia Broadcast Multicast Service (MBMS). In LTE, eMBMS allows combining of MBMS transmission from tightly time synchronized cells by using the same radio configuration in each cells with extended CP. This technique is known as Multimedia Broadcast Single Frequency Network (MBSFN). In order to achieve MBSFN transmission in LTE, the centralized MAC scheduling entity, Multi-cell/multicast Coordination Entity (MCE) is introduced. The Synchronization protocol also runs between eNB and BMSC (Broadcast Multicast Service Center) for synchronized delivery of the contents and reordering and detection of lost packets. An MBSFN area consists of a group of cells within an MBSFN Synchronization Area of a network, which are co-ordinated to achieve an MBSFN transmission except for MBSFN reserved cells. UE may only need to consider a subset of the MBSFN areas that are configured. Operator can configure MBSFN areas in MCE through LSM and each MBSFN area must be mapped with MBSFN Synchronization Area ID and Service Area ID. In addition, each MBSFN area shall be configured with system parameters such as the maximum number of eMBMS subframes per radio frame and radio frame allocation period, and so on.

BENEFIT Multicast services can be provided such as live broadcasting, venue casting, etc. A lot of UEs can watch a video over LTE at the same time Pre-downloading, uncast offloading service is possible with the development of apps and extra servers

Operator can enhance unicast throughput by offloading popular contents to multicast.

Operator shall be able to provide multiple tier services for different areas.


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DEPENDENCY Required Network Elements MME, MCE, BMSC

Interface & Protocols M2, M3, M1

Others oSamsung eNB can inter-work with Samsung MCE for eMBMS because an extended M2 interface is used between eNB and MCE. The extended M2 interface include SFN synchronization messages and the extended use of LCID parameter in MBMS SCHEDULING INFORMATION. The value of LCID ranges from 0 to 128 instead of 0 to 28 in order to identify the session that the MCCH Update Time is applied to. oBMSC shall limit the length of timestamp to 57,344, which is multiple times of SFN length (4096 in Samsung eNB) and the greatest number less than the maximum time stamp length of 60,000 per 3GPP TS25.446. oIntermediate routers between eNB and MBMS-GW shall support IP multicast service. oOperator might need additional servers such as streaming server for their eMBMS service network infra-structure.

LIMITATION 8 MBSFN Areas per Cell (SLR 3.1 or later) 16 MBSFN Areas per eNB (SLR 3.1 or later) 16 Sessions per Cell eNB cannot store MBMS data more than 20 seconds due to the limitation of buffer

When BCCH modification period and MCCH modification period are set to be different, an inconsistency between the actual resource allocation and resource allocation information broadcasted in the MBSFN-Subframe Config IE of SystemInformationBlockType 2 can be occurred.


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SYSTEM IMPACT Performance and Capacity MCE provides KPIs such as MBMS Session Setup Success Rate (MSSR), MBMS Session Setup Failure Rate (MSFR) per MBSFN Area for each MBMS Session Start message received from MME. MSSR computes total MBMS Session Start Response messages divided by total number of MBMS Session Start Request messages exchanged with eNBs that belong to a MBSFN Area. MSFR computes total sum of MBMS Session Start Failure messages and cases for no reception of Session Start Request message devided by MBMS Session Start Request message exchanged with eNBs that belong to a MBSFN Area. If MSFR is greater than a threshold (WARNING_LEVEL_MSFR), MCE sends a warding message immediately to LSM so that it can display the message for operator. A default value of WARNING_LEVEL_MSFD is 1.0 %.

FEATURE DESCRIPTION MBMS Service Configuration MBMS Service Area is defined as a geographical area that provides the same MBMS service. MBMS Service areas can be overlapped geographically. When BMSC initiates MBMS Session Start, it decides MBMS Service Areas where it wants to broadcast MBMS data for the session. When MBMS Service Area ID is '0', it means that all of the MBMS capable cells that belong to the corresponding PLMN shall broadcast the session.(3GPP TS23.003). MBMS service area is set by cell through the eNB or the LSM. MBMS Service Area ID is set regardless of the frequency or the SFN synchronization. In other words, a same MBMS Service Area ID is allocated to all cells at the area where the same service is to be provided. In one MBMS service area, all cells must support the specific PLMN. Only if the PLMN is included in the PLMN list supported by cells in the TMGI representing the MBMS session, the MBMS service is provided. (TS 29.061) MBSFN Synchronization Area is a set of cells that can transmit synchronized MBMS data. The eNBs shall be synchronized in terms of SFN over the same carrier frequency. The MBSFN Synchronization Area ID must be set per cell. It may be set via CLI through the eNB or the LSM. If cells use a different frequency or the SFN synchronization between cells is different (for example, if the eNB vendors are different or the SFN synchronization among eNBs is different by using the SyncE,) they must be set to have different MBSFN Synchronization Area ID values. One cell belongs to only one MBSFN synchronization area. The MBSFN Synchronization Area ID has the value between 0 and 65535 (3GPP TS36.443 9.2.1.20). MBSFN Area is a set of cells where the same set of eMBMS sessions are broadcast in a synchronized manner. MCE uses the same scheduling information for cells that belong to the same MBSFN Area. MBSFN Areas can be configured overlapped and a cell supports up to 8 different MBSFN Areas.


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For eMBMS service, operator shall configure MBSFN Synchronization Area ID (SYNC in the below figure) and MBMS Service Area ID (SA in the below figure) for each cell. Operator can configure this information through LSM and this information is downloaded when eNB starts up. As soon as eNB starts up, the eNB will perform M2 setup procedures with the MCE. In M2 SETUP REQUEST message, the eNB shall include the MBSFN Synchronization Area ID and MBMS Service Area ID for each cell. Then, the MCE will find MBSFN Area ID from the configuration data, based on the MBSFN Synchronization Area ID and MBMS Service Area ID. The MBSFN Area ID information is delivered to the eNB in M2 SETUP RESPONSE message. If the eNB fails to find an MBSFN Area ID that is mapped to the MBSFN Synchronization Area ID and MBMS Service Area ID, then operator will be informed of the provisioning error.


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In addition, operator shall configure MBSFN Area IDs(MA in the below figure) in MCE so that each MBSFN Area ID has a different set of MBSFN Synchronization Area ID and MBMS Service Area ID. In other words, the MBSFN Synchronization Area ID and MBMS Service Area ID must be the same in the same MBSFN Area. If they are not properly configured, eMBMS data cannot be broadcast over the target MBMS service area. The following table shows an example where operator configures MBSFN Areas through LSM. For each MBSFN Area configured, additional system parameters shall be configured properly. This information is downloaded to MCE when the MCE starts up. MBSFN

MBSFN

MBMS

Area ID

Synchronization Area ID

Service Area ID

1

1

1

2

1

2

3

2

2

...

...

...

Maximum Number of eMBMS Subframes (3GPP TS36.331 6.3.7)

RFAP (Radio Frame Allocation Pattern)

RFAP Offset

Others

(3GPP TS36.331 6.3.7)

(3GPP TS36.331 6.3.7)

...

256

A guideline for MBSFN Area configuration follows:

Multiple MBSFN areas supporting the same MBMS service area should not be overlapped.

The same service cannot be delivered to multiple MBMS service areas if they consequently have mapped to multiple MBSFN Areas that belong to the same eNB.

It is desirable to consist of the MBSFN areas widely to get the effect of combining radio signals at the edged areas among eNBs for the same service, and to minimize the number of MBSFN areas overlapped per cell to save the radio resources by allocating separate MCCH per MBSFN area.

When cells are not synchronized in terms of SFN or when cells serve a different carrier frequency or when cells serve a different PLMN set, they must have a different MBSFN Synchronization Area ID from each other.

If operator wants to split a geographical region into different MBSFN areas, then operator can assign a different MBSFN Synchronization Area ID. As a result, operator can limit eMBMS service area or separate eMBMS service areas.


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eMBMS Network Architecture For eMBMS service, MCE and BMSC servers must be added to the conventional LTE system. In addition, eNB, MME, PGW, and LSM must be upgraded to the SW package of supporting eMBMS. In Samsung LTE system. MBMS-GW is integrated with PGW and provided and it does not require any separate server. Besides, the routers of the backhaul network between MBSM-GW and eNB must support IP multicast feature. M1 interface (user plane, 3GPP TS25.446) between MBMS-GW and eNB is used while M2 (control plane, 3GPP TS36.443) interface between eNB and MCE and M3 interface (control plane, 3GPP TS36.444) interface between MCE and MME are used.

Samsung eMBMS system can minimize the interference between MBSFN areas because a centralized external MCE schedules eMBMS sessions. In addition, the externally separated MCE server allows the MME to be designed to reduce the SCTP connection load. When the MCE features are integrated into the eNB, the MME must create M3 connection as many as eNBs and as a result, there are problems of increasing the SCTP connection load of the MME and instantly rising the message processing load. In addition, The external MCE server makes it easy to restore eMBMS session in case of eNB failures.

eMBMS Protocol Stacks Figure below depicts eMBMS protocol stack of control plane.

Figure below depicts eMBMS protocol stack of use plane. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Basic Functionality for eMBMS eMBMS cells shall transmit MBSFN reference signals in eMBMS subframes. MBSFN reference signals are only defined for the extended cyclic prefix because the delay spread between transmissions receiving from multiple MBMS cells is expected to be relatively large. They defined for both the 15kHz and 7.5kHz subcarrier spacing, but 15kHz subcarrier spacing is only defined for eMBMS service in Samsung eNB. Antenna port 4 is used to transmit MBSFN reference signals. The sequence used to generate the MBSFN reference signals is a function of the MBMS service area identity. The MBSFN RSs are spaced more closely in the frequency domain than for the non-MBSFN transmission, reducing the separation to every other subcarrier instead of every sixth subcarrier. This improves the accuracy of the channel estimation that can be achieved for the longer delay spreads. The channel estimate obtained by the UE from the MBSFN RS is a composite channel estimate, representing the composite channel from the set of cells transmitting the MBSFN data. eNB provides IPv4 and IPv6 multicast functionality. eNB can join a specific multicast group that MCE provides in MBMS Session Start Request message. eNB provides SIB2, SIB13, SIB15 (Rel11), and SIB16 (Rel11). SIB2 and SIB13 information shall be consistent. For this, they need to be scheduled in the same SIB group that has the same System Information Periodicity. In addition, eNB shall broadcast SIB3 that has eMBMS related information. NeighCellConfig in SIB3 can help UE make a fast decision about the change of MBSFN configuration when it moves from cell to cell. When the neighbor cells has the same MBSFN subframe configuration as the serving cell, the parameter must be set to '10'.


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Call Flows The information flows as shown below explain the overall MBMS session setup and MBMS data transmission procedures.

1) When booting up, MCE performs M3 setup procedures. This procedures are supported from 3GPP Release 11. 2) When booting up, eNB performs M2 setup procedures to MCE. Even if there is no cell registered in a MBMS service area, it performs the M2 setup procedures, in which case, the M2 setup message does not include the cell registered to any MBMS service area. The MCE responses with M2 setup response message.


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3) and 4) For eMBMS service, BMSC shall send Service Announcement messages to UEs. This procedure can be performed over HTTP or SMS. eNB, MCE, MME, MBMS-GW cannot recognize this procedure. 5), 6), and 7) BMSC sends MBMS Session Setup message to MCE. Based on MBMS Service Area information in the message, MBMS-GW and MME routes the message to the appropriate MCEs that serve the MBMS Service Area. 8) MCE delivers the MBMS session start request message to all eNBs registered in the MBMS service area requested from the MBMS session setup message. 9) After receiving the MBMS session start message, the eNB uses the given TNL address to join the IP multicast service and prepares to receive a multicast packet from the BMSC. 10) The MCE performs the function of allocating resources for eMBMS sessions in time domain and sends the MBMS Scheduling Information to the eNBs of the MBSFN Areas that provides the MBMS Service Area. Depending on the MBSFN Area, the scheduling information can be different. 11) and 12) eNBs broadcast changed system information of SIB 13 and MCCH and SIB2 if necessary. The system information change notification must be performed at least 5.12 seconds before the eNB starts to transmit MBMS data for the newly added channel. 13) After the Minimum Time to MBMS Data Transfer that BMSC specifies in the MBMS Session Start message, the BMSC starts to transmit MBMS packets to MBMS-GW. When transmitting MBMS data, BMSC marks a time stamp to each packet for data transmission synchronization between eNBs. 14) MBMS-GW multicasts a packet received from the BMSC to eNBs. 15) The eNBs broadcast the data of each MBMS session according to the schedule set received from the MCE.

IP Multicast (M1 Interface) Link redundancy is provided for M1 interface. If the primary M1 interface goes down, the eNB will try to send IGMP join message through the secondary M1 interface. If eNB receives multicast packets from both M1 interfaces, it processes the packets received from the interface that the eNB joined through and the other packets are discarded.


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Synchronization For eMBMS service, eNBs that belong to the same MBSFN Area must broadcast the same eMBMS data at the same time, so eMBMS UEs in the boarder area of eNBs can combine radio signals from multiple eNBs to decode MBMS data without interference. For this, the eNBs should be basically synchronized in terms of SFN. In order to help eNB schedule the same MBMS packet in the same time slot, SYNC protocol is used between eNB and BMSC. BMSC marks a timestamp per each MBMS packet. Then, eNB sends the MBMS packet in the radio frame of SFN = (Timestamp + Offset) % 4096. For example, when Timestamp = 0 and Offset = 512, the packet with Timestamp = 0 will be broadcast in the radio frame of SFN = 512 and the packet with Timestamp = 8 will be broadcast in the radio frame of SFN = 520. MCE decides the Offset value when it receives MBMS Session Start request message from BMSC. Due to the short lifecycle of SFN and different backhaul delays, eNBs can be confused with the timestamp. For example, when eNB receives a packet with timestamp that has just passed in terms of SFN, it will wait for another SFN lifecycle to send out the packet. In order to resolve this problem, eNB will discard packets that arrives TimeBack seconds late, and buffers packets that arrives up to TimeAhead in advance. See the following figure.

eMBMS Statistics and KPI Samsung eMBMS system provides session monitoring functionality. See LTESV0515 eMBMS Session Monitoring feature for details. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Service Restoration In case of the eNB restart, the eNB re-receives the session start message and scheduling information from the MCE. At the time, the MCE transmits the MCCH-UP time that has been transmitted initially for this session to the eNB again. Accordingly, the eNB may restore the SFN Offset value same as the neighbor eNB for the session. Upon the eNB restart, it will discard all MBMS data accumulated in the buffer and transmits the newly received packet based on the restored SFN Offset value. To allow such eNB restart, the length of timestamp used in the BMSC must be a multiple of the length of the SNF of the eNB.

SFN length of eNB: 4096 Timestamp length of BMSC: 4096 x 14 = 57344 (Finding the maximum multiple value of 4096 within the maximum value of 60000 set in the standard). In other words, the timestamp used by the BMSC operates totally 57344 from 0 to 57343.

eMBMS Packet Transmission Delay According to the MBMS packet transmission scheme of the 3GPP, the time of transmitting the packet from the eNB to the UE may be delayed up to 5.12 seconds in preparation of the time requested by the BMSC. (When the MCCH modification period is rf512,) it is because the time of opening the radio channel in the eNB is defined in the standard to be based on the MCCH modification period. After receiving the session start message from the BMSC and anticipating a packet to arrive late as much as the Minimum_Time_to_MBMS_Data_Transfer set by the BMSC, the MCE sets the fastest MCCH modification boundary point, coming later as much as the Minimum_Time_to_MBMS_Data_Transfer from the current time, as the MCCH update time. The eNB starts to transmit the first packet (TS = 0) of the session at the MCCH update time set by the MCE. After that, it makes the transmission time difference from the previous packet as much as TS designated to each packet kept and transmits the packet. Therefore, when the packet arrives too fast to the eNB, the packet is buffered until the time designated to the TS and then transmitted and when it arrives too late, the eNB discards. Therefore, to prevent the packet from dropped by the eNB because the packet arrives too late, it is safe to transmit the packet earlier for roughly 2 to 3 seconds than the determined time with the BMSC in consideration of the delay of the backhaul network (generally dozens to hundreds of ms). At the time, when the MBSC transmits the packet too earlier, the packet may be discarded because the data buffered due to the limited buffering capacity of the eNB increases.

eMBMS Session Dimensioning Rules MCE manages up to 256 different MBSFN areas and may support up to 8 areas per cell and up to 16 per eNB. One MCCH per MBSFN area is allocated and may consist of up to 15 PMCHs. In addition, one PMCH may set up to 16 sessions (including MCCH).


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Samsung eNB supports up to 256 sessions (including MTCH and MCCH). Within the scope not exceeding 256 sessions, it supports up to 8 MBSFN areas per cell and 16 per eNB. Actually, during the operation, the number of sessions that may be supported by the eNB according to the throughput of the session requested by the operator may be limited. For example, the eNB that may support 5 Mbps can support up to 5 sessions requiring 1 Mbps. Category

Capacity

Comments

Number of MBSFN Areas

256 per MCE 16 per eNB 8 per Cell

-

Number of PMCHs

15 PMCH per MBSFN Area

-

Number of Sessions(MTCH)

256 Sessions per MCE 256 MTCHs per eNB 16 Sessions per Cell

-

Number of eNB per MCE

1000 eNB per MCE(2013.09) 3000 eNB per MCE(2014.03)

-

eMBMS In RAN Sharing(PLMN-based Service Control) In the RAN sharing environment, the administrator must configure MBMS service areas per PLMN and manage the list of available MBMS Service Area IDs for each PLMN. The MBMS service area for a specific service is decided when BMSC includes a specific PLMN ID and MBMS Service Area ID for the session ID(TMGI). eNB will not broadcast eMBMS data if the eMBMS session's TMGI does not include a PLMN ID that the cell supports.

Requirements on BMSC Timestamp of a MBMS session must begin with 0. The length of timestamp must be 57344, which is integer times of SFN length (4096) of Samsung eNB.

BMSC shall send an empty packet(SYNC PDU Type 0) if there is no MBMS data to send.

Synchronization Sequence Length is 80ms, which means the timestamp shall increase by 8. eNB performs eMBMS scheduling every 80ms when MSP(MCCH Scheduling Period) is set to 80ms.

BMSC shall expect that MBMS data can be taken randomly 0 to 5.12 seconds before it is delivered to UE due to MCCH modification period as per 3GPP standard.

In order to minimize buffering at eNB, it is desirable that BMSC shall send eMBMS data at a constant bit rate within GBR as possible as it can.

It is recommended that BMSC starts to sends the first MBMS packet roughly 2 seconds earlier than the actual Minimum Time to MBMS Data Transfer in consideration of the backhaul delay.


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BMSC shall not transmit MBMS data too earlier than 20 seconds. eNB may discard the packet thinking the time has passed or eNB may experience buffer overflow.

The QCI is decided in consideration of the MCS level. Refer to the QCI to MSC level mapping table as configured in the LSM. See LTE-SV0511 eMBMS QoS for details.



The eNB MBMS service information shall be properly configured. The eNB MBSFN information shall be properly configured. The eNB MBMS information shall be properly configured. Activation Procedure To activate this feature, do the following:

Run CHG-ENBMBMSSVC-CONF to configure the eNB MBMS service information.

Run CHG-MBSFN-INFO to configure the eNB MBSFN information. Run CHG-ENB-MBMSINFO to configure the eNB MBMS information and then set MBMS_SERVICE_STATE to Active to enable the MBMS service. Deactivation Procedure Run CHG-ENB-MBMSINFO to set MBMS_SERVICE_STATE to Inactive to disable the MBMS service.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ENB-MBMSINFO/RTRV-ENB-MBMSINFO Parameter

Description

CELL_NUM

This is the cell number. This is the key index.


817


Description

MBMS_SERVICE_STATE

This determines whether to enable or disable this feature: Inactive: This feature is not used. Active: This feature is used.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-ENBMBMSSVC-CONF/RTRV-ENBMBMSSVCCONF Parameter

Description

MCC

This is the Mobile Country Code (MCC) that comprises Public Land Mobile Network (PLMN) for MBMS service.

MNC

This is the Mobile Network Code (MNC) that comprises Public Land Mobile Network (PLMN) for MBMS service.

CELL_RESELECTION_SWI TCH

This determines whether to enable or disable the eMBMS cell reselection functionality: Off: This functionality is not used. On: This functionality is used. The eMBMS cell reselection functionality is to assign the highest priority to EARFCN of eMBMS on the IdleModeMobilityControlInfo IE of the RRCConnectionRelease message when a UE which is receiving or is interested to receive eMBMS is transiting to the RRC idle mode.

Parameter Descriptions of CHG-MBSFN-INFO/RTRV-MBSFN-INFO Parameter

Description

CELL_NUM


DB_INDEX

This is the DB index.

MBMS_SERVICE_AREA_U SAGE

This determines whether the related MBSFN area information is used or not: no_use: The related MBSFN area information is not used. use: The related MBSFN area information is used.

MBMS_SERVICE_AREA_ID

This Indicates an MBMS service area including a set of MBMS Service Area Identities (MBMS SAIs).

Parameter Descriptions of CHG-ENB-MBMSINFO/RTRV-ENB-MBMSINFO Parameter

Description

CELL_NUM


MBMS_SERVICE_STATE

This determines whether to enable or disable this feature: Inactive: This feature is not used. Active: This feature is used.

MBSFN_SYNC_AREA_ID_ AUTO_ENABLE

This determines whether the value of the MBSFN_SYNC_AREA_ID attribute is automatically generated or not: Off: The value of the MBSFN_SYNC_AREA_ID attribute is not automatically generated. On: The value of the MBSFN_SYNC_AREA_ID attribute is automatically generated.


818


Description

MBSFN_SYNC_AREA_ID

This is the MBMS Synchronization Area Identity.


Type Name

Type Description

MBMS eNB Signaling

M2ConnEstabAtt

Counted when the eNB has attempted to transmit the M2AP M2 SETUP REQUEST message to the MCE.

M2ConnEstabSucc

Counted when the eNB has received the M2AP M2 SETUP RESPONSE message from the MCE.

M2ConnEstabFail_M2A P_CU_FAIL

Counted when the eNB has received the M2AP M2 SETUP FAILURE message from the MCE since the M2 setup procedure failed due to a cause defined in the 3GPP TS 36.443 specification.

M2ConnEstabFail_M2A P_LINK_FAIL

Counted when the eNB cannot receive the M2AP M2 SETUP RESPONSE/FAILURE message from the MCE during the M2 setup procedure.

SessionStartAtt

Counted when the eNB has received the M2AP MBMS SESSION START REQUEST message from the MCE.

SessionStartSucc

Counted when the eNB has transmitted the M2AP MBMS SESSION START RESPONSE message to the MCE.

SessionStartFail_M2AP _CU_FAIL

Counted when the eNB has transmitted the M2AP MBMS SESSION START FAILURE message to the MCE since the MBMS session start procedure failed due to a cause defined in the 3GPP TS 36.443 specification.

SessionStartFail_M2AP _LINK_FAIL

Counted when the eNB cannot transmit the M2AP MBMS SESSION START RESPONSE/FAILURE message to the MCE during the MBMS session start procedure.

SessionStopAtt

Counted when the eNB has been received the M2AP MBMS SESSION STOP REQUEST message from the MCE.

SessionStopSucc

Counted when the eNB has transmitted the M2AP MBMS SESSION STOP RESPONSE message to the MCE.

SessionStopFail_M2AP _LINK_FAIL

Counted when the eNB cannot transmit the M2AP MBMS SESSION STOP RESPONSE message to the MCE during the MBMS session stop procedure.

SyncPDU_Type0_RxC ount

Counted when the eNB has received SYNC PDU Type 0 by the SYNC handler.





DroppedSyncSequence Count

Counted when SYNC sequence has been discarded.

DroppedSyncPDUCoun

Counted when SYNC PDUs with invalid TEIDs has

MBMS eNB Sync


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Type Name t_INVALID_TEID

Type Description been dropped. The number of dropped SYNC PDUs has been counted.

DroppedSyncPDUByte _INVALID_TEID

Counted when SYNC PDUs with invalid TEIDs has been dropped. The number of bytes of dropped SYNC PDUs has been counted.


REFERENCE [1] 3GPP TS 36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2 [2] 3GPP TS 29.061 SGmB interface [3] 3GPP TS 29.274 Sm interface [4] 3GPP TS 25.446 MBMS Synchronization Protocol(SYNC) [5] 3GPP TS 36.444 M3AP [6] 3GPP TS 36.443 M2AP [7] 3GPP TS36.331 eMBMS RRC [8] 3GPP TS 22.246 MBMS User Service stage 1 [9] 3GPP TS26.346 Multimedia Broadcast/Multicast Service(MBMS); Protocols and codecs [10] 3GPP TS23.246 Multimedia Broadcast/Multicast Service(MBMS); Architecture and functional description


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LTE-SV0502, MBMS Counting INTRODUCTION The MBMS Counting feature is used as a criterion to obtain the optimal resource utilization when switching between broadcast and unicast. It is also used as statistics to provide viewing rate of MBMS broadcasting contents.

BENEFIT This feature enables an operator to collect the number of UE currently receiving or interested to receive certain services within an eNB or an MBSFN Area.

The counted number can be used for further eMBMS service enhancement, such as broadcast switching from unicast or vice-versa and audience measurement.


Interface & Protocols M2, M3

Prerequisite Features eMBMS Basic Function (LTE-SV0501), Multicell and Multicast Coordination (MCE) (LTE-SV0503), eMBMS Resource Allocation (LTE-SV0504) are basically needed for eMBMS.

Others Rel-10 UE that supports MBMS counting

LIMITATION None

SYSTEM IMPACT Interfaces In M2AP interface (between eNB and MCE), MBMSServiceCounting Request/Response/Faulure/ResultsReport messages are added. In air interface between eNB and UE, MBMSCountingRequest and MBMSCountingResponse messages are added.


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FEATURE DESCRIPTION General MBMS counting in an LTE network is used to determine if there are sufficient UEs interested in receiving a service. Based on this, the operator can decide whether it is appropriate to deliver the service via MBSFN.

MBMS counting applies only to connected mode UEs. It allows the operator to choose between enabling or disabling MBSFN transmission for the service.

The network counts the number of UEs interest per service. The network only gets one response from a UE related to one Counting Request message, which is broadcast for one modification period (5.12 s or 10.24 s).

The UE can report on multiple MBMS services via one Counting Response message.

Counting Procedure MBMS Counting begins by sending the M2 MBMSServiceCountingRequest message for MCE to eNBs within all MBSFN areas which range from MBSFN Area 1 to n.

Each eNB sends MBMSCountingRequest message to UEs within its coverage. This message is included in the directly extended MCCH message and contains a list of TMGI‟s requiring UE feedback. The maximum number of TMGIs within a list is 16.

Connected mode UEs, which are receiving or interested in the indicated services for MBMSCountingRequest message, sends the MBMSCountingResponse message. This response message includes short MBMS services identities (unique within the MBSFN service area).

The eNB sends UE counting results to MCE with MBMSServiceCountingReport message. Figure below depicts the counting procedure in case of successful operation (refer to TS36.443 for unsuccessful operation and abnormal conditions).


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This scenario is made up of the following flows:

1 The MCE sends the M2 MBMSServiceCountingRequest message to all eNBs within MBSFN areas with a preconfigured period (default: 5 minutes). This message includes the MCCH Update Time, MBSFN Area ID, and MBMS Counting Request Session.

2 Each eNB receiving the MBMSServiceCountingRequest message transmits the MBMSServiceCountingResponse message to MCE to acknowledge the successful receipt of the request message.

3 The MCCH information change notifications on PDCCH are transmitted periodically, and are carried on MBSFN subframes only. Subframe position of MCCH information change notification is configurable by parameters included in SystemInformationBlockType13: repetition coefficient, radio frame offset and subframe index. The DCI format 1C with M-RNTI is used for notification and includes an 8-bit bitmap to indicate the one or more MBSFN Area(s) in which the MCCH change(s). Within this bitmap, the bit at the position indicated by the field notificationIndicator is used to indicate changes for that MBSFN area. If the bit is set to 1, the corresponding MCCH will change.

4 The eNB transmits MCCH with the MBMSCountingRequest message with a repetition period only during the indicated MCCH modification period.

5 The eNB receives the MBMSCountingResponse message which includes the MBSFN Area Index and countingRequestList that containing a list of TMGI from the connected mode UEs

6 The eNB transmits the MBMSServiceCountingResultsReport message, which includes the results of UE counting per TMGI for the indicated MBSFN Area to MCE

SYSTEM OPERATION This section describes how to configure the feature in Samsung system and provides associated key parameters, counters, and KPIs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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How to Activate This section provides the information that you need to configure the feature. Preconditions This feature shall not be deactivated when the eMBMS unicast fallback feature is enabled. Activation Procedure Run CHG-MCE-COUNTINGINFO and set COUNTING_ENABLE to On to enable the MBMS counting. Deactivation Procedure Run CHG-MCE-COUNTINGINFO and set COUNTING_ENABLE to Off to disable the MBMS counting.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MCE-COUNTINGINFO/RTRV-MCECOUNTINGINFO Parameter

Description

COUNTING_ENABLE

This determines whether to enable or disable this feature: Off: This feature is not used. On: This feature is used.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MCE-COUNTINGINFO/RTRV-MCECOUNTINGINFO Parameter

Description

COUNTING_PERIOD

This is the execution period of the MBMS counting.


Type Name

Type Description

MBMS Counting

MBMSCountingReq

Counted when the MCE has transmitted the M2AP MBMS SERVICE COUNTING REQUEST message to the eNB.

MBMSCountingRsp

Counted when the MCE has received the M2AP MBMS SERVICE COUNTING RESPONSE message


824


MBMS eNB Signaling

Type Name

Type Description from the eNB.

MBMSCountingFail

Counted when the MCE has received the M2AP MBMS SERVICE COUNTING FAILURE message from the eNB.

MBMSCountingResultsRe port

Counted when the MCE has received the M2AP MBMS SERVICE COUNTING RESULTS REPORT message from the eNB.

MBMSCountingAtt

Counted when the eNB has received the M2AP MBMS SERVICE COUNTING REQUEST message from the MCE.

MBMSCountingSucc

Counted when the eNB has transmitted the M2AP MBMS SERVICE COUNTING RESPONSE message to the MCE.

MBMSCountingFail_M2AP _CU_FAIL

Counted when the eNB has transmitted the M2AP MBMS SERVICE COUNTING FAILURE message to the MCE since the MBMS service counting procedure failed due to a cause defined in the 3GPP TS 36.443 specification.

MBMSCountingFail_M2AP _LINK_FAIL

Counted when the eNB cannot transmit the M2AP MBMS SERVICE COUNTING RESPONSE message to the MCE during the MBMS service counting procedure.

MBMSCountingResultsRe port

Counted when the eNB has transmitted the M2AP MBMS SERVICE COUNTING RESULTS REPORT message to the MCE.

MBMSCountingResultsRe portFail_M2AP_LINK_FAIL

Counted when the eNB cannot transmit the M2AP MBMS SERVICE COUNTING RESULTS REPORT message to the MCE during the MBMS service counting results report procedure.


REFERENCE [1] Release 12 TS 36.300 [2] Release 12 TS 36.331


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LTE-SV0503, Multicell and Multicast Coordination (MCE) INTRODUCTION MCE (Multicell and Multicast Coordination Entity) is an eMBMS entity that controls eMBMS sessions requested by MME and allocates radio resources in time domain and schedules eMBMS sessions. In addition, it aligns the opening of eMBMS radio channel among cells that belong to the same MBSFN Area.

BENEFIT Operator can provide eMBMS service and increase radio resource utilization. Wide MBSFN area is provided that minimizes eMBMS interference between cells.

Continuous eMBMS service is provided even in case when eNB fails and restarts. Resilient MCE system is provided by 1:1 active and standby redundancy


Interface & Protocols M2 I/F, M3 I/F

Others oMME that supports 3GPP Release 11 M3 interfaces oSamsung eNB that supports 3GPP Release 11 M2 interface oRelease 9 and later UE that supports eMBMS oMBMS-GW and BMSC are required for eMBMS service

LIMITATION 256 MBSFN Areas Simultaneous session processing of 10 per 1 second 256 Sessions per MCE(One Blade)


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FEATURE DESCRIPTION Samsung MCE is provided as an external server. Advantages of the centralized MCE architecture is as follows;

SCTP offloading from MME eMBMS service restoration when eNB restarts or fails Large MBSFN areas MCE is an essential entity for eMBMS service. This feature covers following basic and advanced MCE functions:

M2 and M3 interface eMBMS session start and stop based on MBMS Service Area 1:1 Active and Standby redundancy eMBMS session restoration when eNB restarts or fails Inter-MCE scheduling coordination Multiple PLMN supported for RAN sharing For resource allocation and MBMS bearer scheduling, see LTE-SV0504 eMBMS Resource Allocation. In addition to MCE, eMBMS related network entities includes eNB, MME, MBMS GW, and BMSC in the mobile network.

M2 Interface Management According to 3GPP TS36.443, MCE and eNB setup M2 connection and support following procedures.

M2 SETUP procedures to make M2 connection M2 RESET procedures ENB CONFIGURATION UPDATE procedures to update application level eNB configuration data

MCE CONFIGURATION UPDATE procedures to update application level MCE configuration data

ERROR INDICATION procedures M3 Interface Management According to 3GPP TS36.444, MCE and MME setup M3 connection and support following procedures.

M3 SETUP procedures to make M3 connection M3 RESET procedures eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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MCE CONFIGURATION UPDATE procedures to update application level MCE configuration data MCE can make multiple M3 connections with different MMEs.

MBMS Session Management According to 3GPP TS36.443 and 3GPP TS36.444, MCE supports MBMS session control functions.

MBMS SESSION START and STOP procedures initiated by MME MBMS SESSION UPDATE procedure initiated by MME On receiving M3 MBMS SESSION START message from MME, MCE sends M2 MBMS SESSION START message to eNBs that belong to MBSFN Areas that support the MBMS Service Area ID specified in the M3 MBMS SESSION START message. MCE does not use PLMN ID of TMGI in the message when it decides target eNBs or MBSFN Areas. This means that MBMS SESSION START message can be sent to eNBs even though the eNBs does not support the PLMN ID of TMGI in the message. If a eNB does not support the PLMN ID, it should reject the session request. This is to support eMBMS service in RAN sharing network. The session duration parameter in MBMS SESSION START REQUEST message decides the session duration. When it expires, MCE releases the MBMS Session unless it is updated by MBMS SESSION UPDATE REQUEST message. MCE provides M3 related counters per MME including MBMS Session Start Request/Response/Failure, MBMS Session Stop Request/Response, MBMS Session Update Request/Response/Failure. MCE provides M2 related counters per MBSFN Area including MBMS Session Start Request/Response/Failure, MBMS Session Stop Request/Response, MBMS Session Update Request/Response/Failure, MBMS Service Counting Request/Response/Failure/Report.

MCE Redundancy Samsung MCE provides active and standby redundancy. When an active server fails, the standby server takes over the role without any service impact. Figure below depicts an example configuration of MCE. Maximum five active and standby pairs are equipped in a single chassis(HS23). Active and standby servers share the same IP interface so that the active and standby architecture is transparent to eNB or MME. Active server periodically backups data to standby server. When active server fails (SW or HW fails or board reset), the standby server will take over the role in a few seconds. After switchover, MCE makes SCTP setup with all of the eNBs, and MCE also makes SCTP setup with MME. However, these switchover procedures have no impact on ongoing eMBMS data sessions.


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Inter-MCE Scheduling Coordination When a big city or nation-wide area is covered by multiple MCEs, they need to broadcast synchronized eMBMS data over the entire area. For example, there are two MCEs that cover two disjoint areas respectively. Even though the eNBs in two disjoint areas broadcast the same eMBMS service, there could be severe interference in the boarder area if they are not synchronized. The interference can be removed if the eNBs broadcast the same eMBMS data in the same physical location of the frequency at the same time. For inter-MCE scheduling coordination, the MCEs must be configured so that they have the same MBMS Service Area ID with the same physical resource configuration such as RFAP and RFAP offset. In addition, for the MBMS Service Area, they shall receive eMBMS data from the same BMSC. In figure below, the first two MBSFN areas have the same MBMS Service Area and the same physical resource allocation. The coordinated MBMS Service Area must span over the same frequency and over the eNBs that are SFN synchronized. MBSFN Area ID and MBSFN Synchronization Area ID can be different between two MCEs while MBMS Service Area and RFAP and RFAP Offset must be the same. The eNBs in the MBMS Service Areas will be able to transmit synchronized eMBMS data for the same eMBMS session. Each MCE may have its own MBMS Service Area independently of the other MCEs (MBSFN Areas 2 to 256 in the example).

For a MBMS Service Area that needs to be synchronized over multiple MCEs, operator shall configure following system parameters the same over the MCEs. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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MBMS Service Area ID RFAP RFAP Offset MSP MCS Level (Signalling and Data) The number eMBMS subframes per radio frame Configuration of MBSFN Areas that corresponds to the MBMS Service Area. See Information included in MBMS Scheduling Information (3GPP TS36.443 V10.1.0 9.1.7)

Information included in MCCH related BCCH Configuration Item (3GPP TS36.443 V10.1.0 9.2.1.13), excluding MBSFN Area ID and Cell Information List. In addition, following requirements must be met.

The MCEs shall be connected to the same BMSC. The same MBMS Service Area must be configured over the same frequency, the same PLMN

All the eNBs in the same MBMS Service must be SFN synchronized. The MBSFN Areas that serve the MBMS Service Area must not support other MBMS Service Areas that cover local regions. The followings are overall procedures to apply the coordinated scheduling information to MCEs and eNBs.

1 LSM shall provide coordinated scheduling information to the concerned MCEs. 2 Upon receiving the M2 setup request from eNB, the MCE shall provide MCCH configuration information for the cluster MBSFN area.

3 Upon receiving the M2 setup response from MCE, the eNB shall schedule MCCH by given configurations.

4 Upon receiving the M3 session start message for the specific MBMS service area from MME, MCE shall schedule PMCH/MCH by the coordinated scheduling information.

5 Upon receiving the M2 MBMS SCHEDULING INFORMATION message for the specific MBSFN area, the eNB MAC shall schedule PMCH/MCH by the given information.



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Preconditions Ensure that the following conditions are met before enabling this feature:

There must be M2 connection with the eNB and M3 connection with the MME. Parameter Descriptions of CHG-MBMSENB-CONF/RTRV-MBMSENB-CONF Parameter

Description

ENB_INDEX

Index of the eNB. The value entered when registering the MBMS eNB is used.

STATUS

The validity of the MBMS eNB information.

ENB_MCC

The PLMN information (MCC) that represents the MBMS eNB. It is a threedigit number with each digit being from 0 to 9.

ENB_MNC

The PLMN information (MNC) that represents the MBMS eNB. It is a threedigit or two-digit number with each digit being from 0 to 9.

ENB_IP_V4

Enter the IP address of the MBMS eNB in the IP version 4 format.

ENB_IP_V6

Enter the IP address of the MBMS eNB in the IP version 6 format.

Parameter Descriptions of CHG-MBMSMME-CONF/RTRV-MBMSMME-CONF Parameter

Description

MME_INDEX

Index of MME. The value entered when registering the MBMS MME is used.

STATUS

The validity of the MME information.

MME_IP_V4

Enter the IP address of the MME with the M3 connection in the IP version 4 format.

MME_IP_V6

Enter the IP address of the MME with the M3 connection in the IP version 6 format.

Activation Procedure This feature runs automatically. Deactivation Procedure This feature does not need to be deactivated.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Configuration Parameter To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MBSFN-MAPPINGINFO/RTRV-MBSFNMAPPINGINFO Parameter

Description

MBSFN_AREA_ID

Index for changing and retrieving MBSFN area id.

STATUS

Status of MBSFN Mapping Info

MBSFN_SYNC_AREA_ID

MBSFN SYNC AREA ID

MBMS_SERVICE_AREA_ID

MBSFN Service AREA ID


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Type Name

Type Description

MBMS_M2_SETUP

M2ConnEstabAtt

The count of M2 Session Setup attempts that is received by the MCE

M2ConnEstabSucc

The count of M2 Session Setup successes that is transmitted by the MCE

M2ConnEstabFail_M2apCu Fail

The count of release due to the M2 specification cause during the M2 Session Setup

M2ConnEstabFail_M2apLi nkFail

The count of release due to M2 SCTP Link failure during the M2 Session Setup

SessionStartAtt

The count of M2 MBMS Session Start request attempts that is transmitted by the MCE

SessionStartSucc

The count of M2 MBMS session start response success that is received by the MCE

SessionStartFail_CpCcFail

The count of release due to reset notification (MCE failure or block restart) from MMCB or by MCCB during the M2 MBMS Session Start procedure

SessionStartFail_CpCapaC acFail

The count of release due to insufficient capacity-based MCE resources during the M2 MBMS session Start procedure

SessionStartFail_M2apCuF ail


SessionStartFail_M2apLink Fail


SessionStopAtt

The count of M2 MBMS Session Stop Request attempts transmitted by the MCE

SessionStopSucc

The count of M2 MBMS Session Stop Response successes received by the MCE

SessionStopFail_CpCcFail

The count of release due to reset notification (MCE failure or block restart) from ECMB or by ECCB during the M2 Session Stop procedure

SessionStopFail_M2apLink Fail

The released count due to M2 SCTP Link failure during M2 Session Stop

SessionStartFail_M2Other Reasons

The number of failures due to an exceptional situation other than the reason specified by the statistics in the MCE

SessionUpdateAtt

The number of M2 MBMS Session Update Request transmitted from MCE to the eNB

SessionUpdateSucc

The number of M2 MBMS Session Update Response transmitted from eNB to the MCE

SessionUpdateFail_M2AP_ CU_FAIL

The number of M2 MBMS Session Update Failure according to cause in 3GPP TS 36.443 specification

SessionUpdateFail_M2AP_ TO

The number of failure to response in M2 MBMS Session Update procedure

SessionDrop_M2SCTP_O OS

The cumulate number of dropped sessions when Out of Service occurs on M2 SCTP

SessionDrop_M2Reset

The cumulate number of sessions that the


832


Type Name

Type Description message to eNB contains when MCE receive M2 Reset(partial), and it sends back M2Session Start Request to eNB.

MBMS_SESSION_SETUP

SessionStartAtt

The count of M3 MBMS session start request attempts received by the MCE

SessionStartSucc

The count of M3 MBMS session Start response successes transmitted by the MCE

SessionStartFail_CpCapaC acFail

The count of release due to insufficient capacity-based MCE resources during the M3 MBMS session Start procedure

SessionStartFail_M3apCuF ail


SessionStartFail_M3apLink Fail


SessionStopAtt

The count of M3 MBMS session stop request attempts received by the MCE

SessionStopSucc

The count of M3 MBMS session stop response successes transmitted by the MCE

SessionStopFail_CpCcFail

The count of release due to reset notification (MCE failure or block restart) from MMCB or by MCCB during the M3 MBMS Session Stop procedure

SessionStopFail_M3apLink Fail

The count of release due to M3 SCTP Link failure during M3 Session Stop

SessionUpdateAtt

The number of M3 MBMS Session Update Request transmitted from the MME to the MCE

SessionUpdateSucc

The number of M3 MBMS Session Update Response transmitted from the MCE to the MME

SessionUpdateFail_M3AP_ CU_FAIL

The number of M3 MBMS Session Update Failure according to cause in 3GPP TS 36.444 specification

SessionUpdateFail_M3AP_ LINK_FAIL

The number of M3 SCTP link failure in M3 MBMS Session Update procedure

M3ConnEstabAtt

The number of M3 Setup Request transmitted from the MCE to the MME

M3ConnEstabSucc

The number of M3 Setup Response received by MME

M3ConnEstabFail_CpCcFa il

The number of timeout when MCE does't receive M3 Setup Response from MME

M3ConnEstabFail_M3apCu Fail

The number of M3 Setup Failure received by MME

M3ConnEstabFail_M3apLi nkFail

The number of SCTP link fail during M3 Setup procedure.

M3MceConfigUpdateAtt

The number of M3 MCE Configuration Update transmitted from the MCE

M3MceConfigUpdateSucc

The number of M3 MCE Configuration Update Ack received by MME

M3MceConfigUpdateFail_C pCcFail

The number of timeout when MCE does't receive MCE Configuration Update Ack from MME

MBMS_M3_SETUP

MBMS_M3_MCE_UPDATE


833


MBMS_MBSFN_SESSION

Type Name

Type Description

M3MceConfigUpdateFail_ M3apCuFail

The number of M3 MCE Configuration Update Failure received by MME

M3MceConfigUpdateFail_ M3apLinkFail

The number of SCTP link fail during M3 MCE Configuration Update procedure.

SessionStartAtt

The number of M2 MBMS Session Start Request transmitted from MCE to the eNB in MBSFN area

SessionStartSucc

The number of M2 MBMS Session Start Response transmitted from eNB to the MCE in MBSFN area

SessionStartFail

The number of M2 MBMS Session Start Failure transmitted from eNB to the MCE in MBSFN area

Table below outlines the main Key Performance Indicators (KPIs) associated with this feature. Family Display Name

Type Name

Type Description

MBMS_MBSFN_SESSION

MSSR

Session Start Success Rate in 'M2: Session Start Request' procedure in MCE with each MBSFN area.

MSFR

Session Start Failure Rate in 'M2: Session Start Request' procedure in MCE with each MBSFN area.

REFERENCE [1] 3GPP TS 36.443 [2] 3GPP TS 36.444


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LTE-SV0504, eMBMS Resource Allocation INTRODUCTION MCE performs an eMBMS scheduler role allocating eMBMS radio resource to each MBMS session. The eMBMS scheduling is performed for each MBSFN area. eNB transmits eMBMS data according to the scheduling information provided by MCE. In addition, MCE performs MBMS session admission control functionality, where MCE checks the capacity of MBSFN area, MCE, eNB, and cell to decide whether it accepts the call or not. In addition, MCE maintains allocated resources and makes an admission decision based on GBR requested in MBMS Session Start Request from BMSC.

BENEFIT This feature facilitates efficient radio resource allocation with the statistical multiplexing of the logical channels into a given physical subframe.


Interface & Protocols M2 I/F, M3 I/F

Prerequisite Features LTE-SV0501 (eMBMS Basic Function)

Others oUE shall support eMBMS service. oeNB and MCE are required to support eMBMS service.

LIMITATION Up to 15 PMCHs can be supported in one MBSFN Area Up to 256 MBSFN Areas

SYSTEM IMPACT Interdependencies between Features PRACH configuration index should be carefully selected not to transmit Random Access Response (RAR) on MBSFN subframes. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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FEATURE DESCRIPTION eMBMS Channels The channels used in LTE eMBMS are largely classified into a logical channel, a transport channel, and a physical channel and they are mapped with each channel as shown below.

Logical channel: MCCH, MTCH Transport channel: MCH Physical channel: PMCH

eMBMS Radio Resource Allocation Below is the procedure flow explaining the resource allocation in the MCE. The MCE performs resource allocation based on the MBSFN area, PMCH, QCI, GBR, etc. after receiving the MBMS session start request message from the BMSC. If the resource allocated for eMBMS is not sufficient, the MCE transmits the MBMS session start failure (Session Reject) message to the MME.


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In Step 0, The MCE decides on which MBSFN area a new session (ID: TMGI) will be added based on the service area ID included to the MBMS session start request message. In Step 1, the number of all physical radio frames for the session in the MBSFN area decided in Step 0 is calculated with the following process.



Obtain the data MCS level mapped to the MBSFN area with QCI-Data MCS Mapping table



Calculate the number of total available MBSFN subframes within Common Subframe Allocation Period (CSAP) from MAX_Subframe_num, Radio Frame Allocation Period (RFAP).



Obatin the size of data volume that should be transmitted for the session during CSAP.


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Chapter 9 Services



Calculate total number of subframes by applying signalling MCS for the signalling like MCCH, MSI and applying data MCS for data traffic.



If the resource is insufficient, reject the request.

In Step 2, a PMCH is configured by MCCH Repetition Period, CSAP, MCH Scheduling Period (MSP), Radio Frame Allocation Period (RFAP), Radio Frame Allocation Offset (RFAO) and so on.

Resource Allocator Enhancement Interleaved Broadcast (Burst Packet loss resiliant) support When creating a subframe allocation pattern, the distance between subframes is maximized. TD-LTE UL/DL Configuration 2 for oneFrame: {3}, {3,9}, {3,9,4}, {3,9,4,8} FD-LTE bitmap patterns for oneFrame: {1}, {1, 8}, {1, 3, 8},{1, 3, 6, 8}, {1, 2, 3, 6, 8}, {1, 2, 3, 6, 7, 8}

Dynamic change of RFAP and MBSFN subframe pattern.

RFAP and MBSFN subframe allocation pattern (bitmap pattern) are dynamically changed according to the required number of MBSFN subframes.

RFAO is unique for each MBSFN area. CSAP and MSP are fixed to 320 ms which was a default value in the previous version.

According to the required number of MBSFN subframes to support the requested sessions, RFAP and bitmap pattern are determined.

RFAP will be dynamically adjusted from 320ms(rf32) to 10ms(rf1) (rf32  rf16  rf8  rf4  rf2  rf1).

Bitmap pattern for the maximum number of MBSFN subframes which is configured by operator („MAX_SUBFRAME_NUM‟) is pre-configured. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 9 Services

MBSFN subframe allocation table for TDD oneFrame When 1 MBSFN area is configured, the available RFAPs are 32, 16, 8, 4, 2 and 1. When 2 MBSFN areas are configured, the available RFAPs are 32, 16, 8, 4 and 2. When 4 MBSFN areas are configured, the available RFAPs are 32, 16, 8, and 4. When 8 MBSFN areas are configured, the available RFAPs are 32, 16, and 8. When MAX_SUBFRAME_NUM’ = 1

When MAX_SUBFRAME_NUM’ = 2

Bit allocation for each subframe number


RFAP

# of Subframes

3

4

8

9

RFAP

# of Subframes

3

4

8

9

32

1x1

1

1

X

X

X

32

1x1

1

1

X

X

0

16

1x2

2

1

X

X

X

16

1x2

2

1

X

X

0

8

1x4

4

1

X

X

X

8

1x4

4

1

X

X

0

4

1x8

8

1

X

X

X

4

1x8

8

1

X

X

0

2

1x16

16

1

X

X

X

2

1x16

16

1

X

X

0

1

1x32

32

1

X

X

X

1

1x32

32

1

X

X

0

-

-

-

-

-

-

-

1

2x32

64

1

X

X

1





RFAP

# of Subframes

3

4

8

9

RFAP

# of Subframes

3

4

8

9

32

1x1

1

1

0

X

0

32

1x1

1

1

0

0

0

32

2x1

2

1

0

X

1

32

2x1

2

1

0

0

1

32

3x1

3

1

1

X

1

32

3x1

3

1

1

0

1

16

2x2

4

1

0

X

1

16

2x2

4

1

0

0

1

16

3x2

6

1

1

X

1

16

3x2

6

1

1

0

1

8

2x4

8

1

0

X

1

8

2x4

8

1

0

0

1

8

3x4

12

1

1

X

1

8

3x4

12

1

1

0

1

4

2x8

16

1

0

X

1

4

2x8

16

1

0

0

1

4

3x8

24

1

1

X

1

4

3x8

24

1

1

0

1

2

2x16

32

1

0

X

1

2

2x16

32

1

0

0

1

2

3x16

48

1

1

X

1

2

3x16

48

1

1

0

1

1

2x32

64

1

0

X

1

1

2x32

64

1

0

0

1

1

3x32

96

1

1

X

1

1

3x32

96

1

1

0

1

-

-

-

-

-

-

-

1

4x32

128

1

1

1

1


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Chapter 9 Services

MBSFN subframe allocation table for TDD fourFrame For fourFrame, only two MBSFN areas can be configured. When 1 MBSFN area is configured, the available RFAPs are 32, 16, 8, and 4. When 2 MBSFN areas are configured, the available RFAPs are 32, 16, and 8. When MAX_SUBFRAME_NUM’ = 1 Bit allocation for the 1st radio frame

Bit allocation for the 2nd radio frame

Bit allocation for the 3rd radio frame

Bit allocation for the 4th radio frame

RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

32

1x1

1

1

X

X

X

0

X

X

X

0

X

X

X

0

X

X

X

32

2x1

2

1

X

X

X

0

X

X

X

1

X

X

X

0

X

X

X

32

3x1

3

1

X

X

X

1

X

X

X

1

X

X

X

0

X

X

X

16

2x2

4

1

X

X

X

0

X

X

X

1

X

X

X

0

X

X

X

16

3x2

6

1

X

X

X

1

X

X

X

1

X

X

X

0

X

X

X

8

2x4

8

1

X

X

X

0

X

X

X

1

X

X

X

0

X

X

X

8

3x4

12

1

X

X

X

1

X

X

X

1

X

X

X

0

X

X

X

4

2x8

16

1

X

X

X

0

X

X

X

1

X

X

X

0

X

X

X

4

3x8

24

1

X

X

X

1

X

X

X

1

X

X

X

0

X

X

X

4

4x8

32

1

X

X

X

1

X

X

X

1

X

X

X

1

X

X

X

When MAX_SUBFRAME_NUM’ = 2 Bit allocation for the 1st radio frame




RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

32

1x1

1

1

X

X

0

0

X

X

0

0

X

X

0

0

X

X

0

32

2x1

2

1

X

X

0

0

X

X

0

1

X

X

0

0

X

X

0

32

3x1

3

1

X

X

0

1

X

X

0

1

X

X

0

0

X

X

0

32

4x1

4

1

X

X

0

1

X

X

0

1

X

X

0

1

X

X

0

32

5x1

5

1

X

X

1

1

X

X

0

1

X

X

0

1

X

X

0

32

6x1

6

1

X

X

1

1

X

X

0

1

X

X

1

1

X

X

0

32

7x1

7

1

X

X

1

1

X

X

1

1

X

X

1

1

X

X

0

16

4x2

8

1

X

X

0

1

X

X

0

1

X

X

0

1

X

X

0

16

5x2

10

1

X

X

1

1

X

X

0

1

X

X

0

1

X

X

0

16

6x2

12

1

X

X

1

1

X

X

0

1

X

X

1

1

X

X

0

16

7x2

14

1

X

X

1

1

X

X

1

1

X

X

1

1

X

X

0

8

4x4

16

1

X

X

0

1

X

X

0

1

X

X

0

1

X

X

0

8

5x4

20

1

X

X

1

1

X

X

0

1

X

X

0

1

X

X

0

8

6x4

24

1

X

X

1

1

X

X

0

1

X

X

1

1

X

X

0

8

7x4

28

1

X

X

1

1

X

X

1

1

X

X

1

1

X

X

0


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Chapter 9 Services When MAX_SUBFRAME_NUM’ = 2 Bit allocation for the 1st radio frame




RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

4

4x8

32

1

X

X

0

1

X

X

0

1

X

X

0

1

X

X

0

4

5x8

40

1

X

X

1

1

X

X

0

1

X

X

0

1

X

X

0

4

6x8

48

1

X

X

1

1

X

X

0

1

X

X

1

1

X

X

0

X

X

1

1

X

X

1

1

X

X

1

1

X

X

0

X

X

1

1

X

X

1

1

X

X

1

1

X

X

1

4

7x8

56

1

4

8x8

64

1





RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

32

1x1

1

1

0

X

0

0

0

X

0

0

0

X

0

0

0

X

0

32

2x1

2

1

0

X

0

0

0

X

0

1

0

X

0

0

0

X

0

32

3x1

3

1

0

X

0

1

0

X

0

1

0

X

0

0

0

X

0

32

4x1

4

1

0

X

0

1

0

X

0

1

0

X

0

1

0

X

0

32

5x1

5

1

0

X

1

1

0

X

0

1

0

X

0

1

0

X

0

32

6x1

6

1

0

X

1

1

0

X

0

1

0

X

1

1

0

X

0

32

7x1

7

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

0

32

8x1

8

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

1

32

9x1

9

1

1

X

1

1

0

X

1

1

0

X

1

1

0

X

1

1

X

1

1

0

X

1

1

1

X

1

1

0

X

1

32

10x1

10

1

32

11x1

11

1

1

X

1

1

1

X

1

1

1

X

1

1

1

X

0

16

6x2

12

1

0

X

1

1

0

X

0

1

0

X

1

1

0

X

0

16

7x2

14

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

0

16

8x2

16

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

1

16

9x2

18

1

1

X

1

1

0

X

1

1

0

X

1

1

0

X

1

16

10x2

20

1

1

X

1

1

0

X

1

1

1

X

1

1

0

X

1

16

11x2

22

1

1

X

1

1

1

X

1

1

1

X

1

1

1

X

0

8

6x4

24

1

0

X

1

1

0

X

0

1

0

X

1

1

0

X

0

8

7x4

28

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

0

8

8x4

32

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

1

8

9x4

36

1

1

X

1

1

0

X

1

1

0

X

1

1

0

X

1

8

10x4

40

1

1

X

1

1

0

X

1

1

1

X

1

1

0

X

1

8

11x4

44

1

1

X

1

1

1

X

1

1

1

X

1

1

1

X

0

0

X

1

1

0

X

0

1

0

X

1

1

0

X

0

0

X

1

1

0

X

1

1

0

X

1

1

0

X

0

4

6x8

48

1

4

7x8

56

1


841





RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

4

8x8

64

1

0

X

1

1

0

X

1

1

0

X

1

1

0

X

1

4

9x8

72

1

1

X

1

1

0

X

1

1

0

X

1

1

0

X

1

4

10x8

80

1

1

X

1

1

0

X

1

1

1

X

1

1

0

X

1

1

X

1

1

1

X

1

1

1

X

1

1

1

X

0

1

X

1

1

1

X

1

1

1

X

1

1

1

X

1

4

11x8

88

1

4

12x8

96

1





RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

32

1x1

1

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

32

2x1

2

1

0

0

0

0

0

0

0

1

0

0

0

0

0

0

0

32

3x1

3

1

0

0

0

1

0

0

0

1

0

0

0

0

0

0

0

32

4x1

4

1

0

0

0

1

0

0

0

1

0

0

0

1

0

0

0

32

5x1

5

1

0

0

1

1

0

0

0

1

0

0

0

1

0

0

0

32

6x1

6

1

0

0

1

1

0

0

0

1

0

0

1

1

0

0

0

32

7x1

7

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

0

32

8x1

8

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

1

32

9x1

9

1

1

0

1

1

0

0

1

1

0

0

1

1

0

0

1

1

0

1

1

0

0

1

1

1

0

1

1

0

0

1

32

10x1

10

1

32

11x1

11

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

0

32

12x1

12

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

1

32

13x1

13

1

1

1

1

1

1

0

1

1

1

0

1

1

1

0

1

32

14x1

14

1

1

1

1

1

1

0

1

1

1

1

1

1

1

0

1

32

15x1

15

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0

1

16

8x2

16

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

1

16

9x2

18

1

1

0

1

1

0

0

1

1

0

0

1

1

0

0

1

16

10x2

20

1

1

0

1

1

0

0

1

1

1

0

1

1

0

0

1

16

11x2

22

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

0

16

12x2

24

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

1

16

13x2

26

1

1

1

1

1

1

0

1

1

1

0

1

1

1

0

1

16

14x2

28

1

1

1

1

1

1

0

1

1

1

1

1

1

1

0

1

16

15x2

30

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

1

1

0

1

1

0

0

1

1

0

0

1

1

0

0

1

8

8x4

32

1

8

9x4

36

1


842





RFAP

# of Subframes

3

4

8

9

3

4

8

9

3

4

8

9

3

4

8

9

8

10x4

40

1

1

0

1

1

0

0

1

1

1

0

1

1

0

0

1

8

11x4

44

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

0

8

12x4

48

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

1

1

1

1

1

1

0

1

1

1

0

1

1

1

0

1

8

13x4

52

1

8

14x4

56

1

1

1

1

1

1

0

1

1

1

1

1

1

1

0

1

8

15x4

60

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0

1

4

8x8

64

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

1

4

9x8

72

1

1

0

1

1

0

0

1

1

0

0

1

1

0

0

1

4

10x8

80

1

1

0

1

1

0

0

1

1

1

0

1

1

0

0

1

4

11x8

88

1

1

0

1

1

1

0

1

1

1

0

1

1

1

0

0

1

0

1

1

1

0

1

1

1

0

1

1

1

0

1

4

12x8

96

1

4

13x8

104

1

1

1

1

1

1

0

1

1

1

0

1

1

1

0

1

4

14x8

112

1

1

1

1

1

1

0

1

1

1

1

1

1

1

0

1

4

15x8

120

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0

1

4

16x8

128

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

MCE Multi-band support MCE shall be able to allocate radio resource for each synchronization area. Each synchronization area shall be set to different ARFCN. It is very likely that the operator may have different allocated bandwidth for each synchronization area, therefore MCE should be able to manage radio resource for each SYNC ID.


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Precautions The two parameters which define the position of the subframe where MCCH change notification is transmitted are 'notificationSfIndex' and 'notiicationOffset' and configurable in our system (CLI commend: RTRV-ENBMCCH-CONF / CHG-ENBMCCH-CONF). But these should be always fixed to the default value: notificationSfIndex = 1 and notiicationOffset = 0 because MCCH change notification should not be transmitted on non-MBSFN subframe according to 3GPP Specification.



Key Parameters This section describes the key parameters for configuration of the feature.


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Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MBMSSCH-INF/RTRV-MBMSSCH-INF Parameter

Description

MBSFN_AREA_ID

This is the MBSFN area identifier. This value is used for the index to reference a tuple.

STATUS

This is the status of MBMS scheduling information: N_EQUIP: The MBMS scheduling information of the selected MBSFN area is invalid. EQUIP: The MBMS scheduling information of the selected MBSFN area is valid.

MAX_SUBFRAME_NUM

This is the maximum value of subframe number.

MCH_SCHEDULING_PERIOD

This is MCH Scheduling Period.

QCI_MBMS_IDX

This is the index of QCI-MCS table of each MBSFN area.

CSAP

This is Common Subframe Allocation Period.

RFAP

This is Radio Frame Allocation Period.

OFFSET

This is Radio Frame Allocation Offset.

Parameter Descriptions of CHG-MCE-CONF/RTRV-MCE-CONF Parameter

Description

SUBFRAME_ALLOC_TYPE

This is the MBSFN subframe allocation type.


REFERENCE [1] TS 36.300 Rel.9 [2] TS 36.331 Rel.9 [3] TS 36.443 Rel.9


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LTE-SV0510, eMBMS Preemption INTRODUCTION A special eMBMS application such as, a public safety group communication that requires to be prioritized for service over other eMBMS sessions may include both the priority level preemption capability and vunerability in M2 session start message from MME to MCE. The priority level and the service identifier are defined at the application layer (BM-SC) for priority and pre-emption purposes. Operator may congiure TMGI as well as its priority at PCRF and the BM-SC (GCSE interworking is out side scope of this feature description). It is mapped by the PCRF and theGCSE/BM-SC to the ARP priority level, pre-emption capability and pre-emption vulnerability indication under the consideration of the respective EPS network.

BENEFIT Session admission control support Priortized public safety support Priortized public warning support

DEPENDENCY HW dependency BM-SC need to support ARP priority with '0' as an exception

Prerequisite Features eMBMS basic function

LIMITATION Preempted session cannot be automatically resumed.

SYSTEM IMPACT Performance and Capacity Due to eMBMS preemption is considered as an exceptional event, the prempted session need to be manually restarted.

FEATURE DESCRIPTION eMBMS preemtion let MCE to preempt an existing eMBMS session, if physical radio resources are deficient. Upon session preemption, MCE send M2 session eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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stop message followed by M2 MBMS Scheduling Inforamtion message. Operation regards of M2 session stop and M2 MBMSSchedulingInformation is same as defined in the eMBMS Basic Function operations. The Application Server (AS) provides an update of the service characteristics towards the PCRF via the Rx interface. The PCRF translates the service characteristics to PCC policies and forwards its policy decision to the BMSC. The BMSC determines, based on policies provided by the PCRF (through GCSE), whether the BM-SC modifies already established bearers or whether the BM-SC establishes dedicated bearer(s) with the determined bearer characteristics. The PCRF shall, at the reception of service authorization from the GCS AS including an indication that is a prioritized GC Session and priority level, ensure that the ARP priority level and pre-emption of default bearer is assigned a prioritized value. In the case of MBMS Delivery, if the priority of an MBMS bearer needs to be changed, based upon a GCS AS decision to change the priority level, the GCS AS performs either:

The Modify MBMS Bearer procedure A new Activate MBMS Bearer procedure and a Deactivate MBMS Bearer procedure replacing the old MBMS bearer service with a new one. In certain network conditions such as congestion, the bearer used for group communication service may be pre-empted.

In the case of Unicast Delivery, the GCS AS is notified by the PCRF of unicast bearer release.

In the case of MBMS Delivery, the related MBMS bearer may be 'suspended' by E-UTRAN, that is, packets are dropped at the eNB without any message sent from eNB to BM-SC. The UE can detect that MBMS delivery is no longer available when the related TMGI is removed from MCCH.


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Chapter 9 Services

IE/Group Name

Presence

Range

IE type and reference

Semantics description

Allocation/Retention Priority

-

-

-

-

>Priority Level

M

-

INTEGER (0..15)

Description: This IE should be understood as the 'priority of allocation and retention' (see TS 23.246 [6]). Usage: Value 15 means 'no priority'. Values between 1 and 14 are ordered in decreasing order of priority, that is, 1 is the highest and 14 the lowest. Value 0 shall be treated as a logical error if received.

>Pre-emption Capability

M

-

ENUMERATED(shall not trigger preemption, may trigger pre-emption)

This IE indicates the preemption capability of the request on other MBMS ERABs

>Pre-emption Vulnerability

M

-

ENUMERATED(not pre-emptable, preemptable)

This IE indicates the vulnerability of the MBMS ERAB to preemption of other MBMS E-RABs.


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Activation Procedure Run CHG-MCE-CONF and set PREEMPTION_SWITCH to On to enable the eMBMS preemption. Deactivation Procedure Run CHG-MCE-CONF and set PREEMPTION_SWITCH to Off to disable the eMBMS preemption.

Key Parameters This section describes the key parameters for activation and deactivation of this feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MCE-CONF/RTRV-MCE-CONF Parameter

Description

PREEMPTION_SWITCH

This determines whether to enable or disable this feature: Off: This feature is not used. On: This feature is used.


REFERENCE [1] TS 36.444 [2] TS 36.443


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Chapter 9 Services

LTE-SV0511, eMBMS QoS INTRODUCTION This feature enables operator to control the MCS level per eMBMS session. When BMSC sends eMBMS Session Start Request message, it includes QCI in the message. Then, the MCE shall have a QCI to MCS level mapping table internally, so that it can use a corresponding MCS level for the eMBMS session.

BENEFIT Operator can provide different eMBMS sessions in different MCS levels depending on device type or geographical area.

Operator can use eMBMS radio resources efficiently.


Interface & Protocols M2, M3

Prerequisite Features eMBMS Basic Function (LTE-SV0501), Multicell and Multicast Coordination (MCE) (LTE-SV0503), eMBMS Resource Allocation (LTE-SV0504) are basically needed for eMBMS.

Others oMCE and LSM shall support this feature. oBMSC should have the same understanding about the QCIs defined for eMBMS. BMSC should include the agreed QCI number in Session Start Messages.

LIMITATION Maximum nine different QCIs can be configured. Maximum four different QCI-MCS level mapping tables are provided.

SYSTEM IMPACT The implementation of this feature does not have any impact on the network. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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FEATURE DESCRIPTION QCI to MCS Level Mapping eMBMS bearers (or MBMS bearer) shall be GBR bearers and associated with the following QoS parameters.

QoS class Identifier (QCI) Allocation and Retention Priority (ARP): Priority level, Pre-emption Capability, and Pre-emption Vulnerability.

Maximum Bit Rate (MBR), which should be set to the same as GBR Guaranteed Bit Rate (GBR) In addition, QCI defines a MCS level according to a QCI-MCS level mapping table that operator pre-configured in MCE. Operator can configure a QCI to MCS level mapping table in MCE as shown in the below table. Use of operator specific QCI is recommended to avoid confusion with standard QCIs. BMSC and MCE shall have the same understanding in using those QCIs. Although below configuration is the default value, operator can change either QCI or MCS level through LSM. Table below outlines QCI to MCS level mapping table. eMBMS QCI

Resource Type

MCS Level

Comment

128

GBR

11

-

129

GBR

12

-

130

GBR

13

-

131

GBR

14

-

132

GBR

24

-

133

GBR

25

-

134

GBR

26

-

135

GBR

27

-

136

GBR

28

-

Default

GBR

13

Default MCS value is used when QCI is not specified.

When MCE receives a MBMS Session Start Request message, it will find the MCS level corresponding to the QCI number in the MBMS Session Start Request message and use it for Data MCS level for the PMCH that serves the eMBMS session. When the message does not include a QCI or it includes a wrong QCI number, then the MCE will use a default MCS level configured in the table.


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Different Tables per MBSFN Area MCE provides different QCI to MCS level mapping table per MBSFN Area. Operator can define maximum four tables which is pre-configured considering geographical eNB deployments or radio condition or services. For example, for the same service, an MBSFN area that covers indoor environment and provides very strong radio signals may have a different QCI-MCS level mapping from the mapping for an MBSFN area that covers outdoor rural environment.



Run CHG-MBMSSCH-INF and set QCI_MCS_IDX as 0~3. Run CHG-MCE-DATAMCSINFO and set DATA_MCS of each QCI. Deactivation Procedure This feature does not need to be deactivated.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameter To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-PUSCH-IDLE/RTRV-MBMSSCH-INF Parameter

Description

QCI_MCS_IDX

This field indicates index of QCI-MCS table of each MBSFN area. (0~3).

Configuration Parameter To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MCE-DATAMCSINFO/RTRV-MCEDATAMCSINFO Parameter

Description


852


Description

DATA_MCS

This parameter is the value of Modulation and Coding Schemes (MCS) of each QCI.


REFERENCE [1] 3GPP TS 36.444 Release 12 [2] 3GPP TS 29.212 Release 12 [3] 3GPP TS 23.203 Release 12


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Chapter 9 Services

LTE-SV0513, eMBMS Service Continuity(SIB15) INTRODUCTION In the multi-carrier network where only one carrier provides eMBMS service, UEs connected to the other carrier could not recognize that the network provides eMBMS service on a neighbor carrier. To resolve this problem, 3GPP Release 11 introduced SIB 15 that carries a list of Service Area ID per carrier. On receiving the SIB15, UE can send the MBMSInterestIndication message to move to the carrier that provides an interested eMBMS service. Then, eNB will handover this UE to the carrier. Currently, in Samsung eNB, operator can configure maximum 10 MBMS-SAIs per carrier that can be broadcast in SIB15.

BENEFIT Users can provide eMBMS service in multi-carrier environments.

DEPENDENCY Required Network Elements MME, MCE, BMSC, eMBMS support required.

Related Radio Technology E-UTRAN (LTE). Multi-carrier LTE service environment.

Prerequisite Features LTE-SV0501 (eMBMS basic function), LTE-SW1007 (Inter-frequency Handover)

Others Release 11 UEs that support eMBMS.

LIMITATION Assumes that max 10 MBMS SAI is provided per carrier.

SYSTEM IMPACT Interdependencies between Features This feature can be activated only when the LTE-SV0501 (eMBMS basic function) and LTE-SW1007 (Inter-frequency Handover) feature is enabled.


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FEATURE DESCRIPTION This feature allows UEs to connect to the MBMS in an MBMS coverage area regardless of the frequency of the MBMS in the multi-frequency environment. For this feature, the eNB performs the following functions:

The eNB announces the frequency information (EARFCN) and SAI (Service Area Identity) information of the MBMS in SIB15.

If the eNB receives an MBMSInterestIndication message from the UE, then the eNB performs the inter-frequency handover of the UE to the corresponding frequency by using the information on the MBMS frequency list (For more information, refer to the LTE-SW1007 Inter-Frequency Handover document). Figure below depicts eMBMS service continuity message flow.

0. The UE maintains its connection at 2.1 GHz. At this time, the UE refers to the information in SIB15 and transmits the MBMSInterestIndication message to the eNB to request the MBMS connection. 1. When the source eNB receives the MBMSInterestIndication message from the UE, the target frequency is selected by referring to mbms-FreqList. 2. The source eNB performs the inter-frequency handover to the selected target frequency. At this time, the target frequency is located by using the Measurement Gap. The inter-frequency handover to the target frequency is performed when the MR is received at the signal strength of the target frequency and exceeds a certain level (measured using Event A4 or Event A5). 3. The target eNB maintains the connection and receives the MBMS. If the UE using eMBMS service transit to Idle mode, eNB decision for eMBMS service UE based on UE sent MBMSInterestIndication message to the eNB. And eNB set the dedicated priority (using Idle mobility) of the eMBMS frequency to the high ranking in the RRC Release message. eMBMS service UE can maintain eMSMS service in the Idle mobility. Figure below depicts the signal flow of MBMS interest indication. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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After receiving the MBMSInterestIndication message from the UE, the eNB refers to CarrierFreqListMBMS-r11 in the message and performs the inter-frequency handover to the target frequency. For more information about the inter-frequency handover feature, refer to the LTE-SW1007 Inter-Frequency Handover Feature document. The following table is MBMSInterestIndication message (TS36.331 v1150). -- ASN1START MBMSInterestIndication-r11::= SEQUENCE { criticalExtensions CHOICE { c1 CHOICE { interestIndication-r11 MBMSInterestIndication-r11-IEs, spare3 NULL, spare2 NULL, spare1 NULL }, criticalExtensionsFuture SEQUENCE {} } } MBMSInterestIndication-r11-IEs::= SEQUENCE { mbms-FreqList-r11 CarrierFreqListMBMS-r11 OPTIONAL, mbms-Priority-r11 ENUMERATED {true} OPTIONAL, lateNonCriticalExtension OCTET STRING OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL } -- ASN1STOP


How to Activate This section provides the information that you need to configure the feature. Preconditions There are no specific preconditions to activate this feature. Activation Procedure Run CHG-SIB-INF, and then set SIB15_PERIOD to one of 80 ms, 160 ms, ..., 5120 ms to set the broadcast interval for SIB15. Deactivation Procedure Run CHG-SIB-INF, and then set SIB15_PERIOD to not_used not to broadcast SIB15. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameters To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SIB-INF/RTRV-SIB-INF Parameter

Description

CELL_NUM


SIB15_PERIOD

This is the broadcast interval for SIB15. 80ms: The broadcast interval for SIB15 is 80ms. 160ms: The broadcast interval for SIB15 is 160ms. ... 5120ms: The broadcast interval for SIB15 is 5,120ms. not_used: SIB15 is not broadcasted.

Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-SIB-INF/RTRV-SIB-INF Parameter

Description

CELL_NUM


SIB15_PERIOD

This is the broadcast interval for SIB15. 80ms: The broadcast interval for SIB15 is 80ms. 160ms: The broadcast interval for SIB15 is 160ms. ... 5120ms: The broadcast interval for SIB15 is 5,120ms. not_used: SIB15 is not broadcasted.

Parameter Descriptions of CHG-EMBMS-SC/RTRV-EMBMS-SC Parameter

Description

E_MBMS_CARRIER_IDX

This is the eMBMS service carrier index. This is the key index.

STATUS

This specifies whether this tuple information is valid: N_EQUIP: This eMBMS service carrier is invalid EQUIP: This eMBMS service carrier is valid

EARFCN_DL

This is downlink E-UTRA Absolute Radio Frequency Channel Number (EARFCN) of eMBMS service carrier.

SAI_USAGE

This is the usage flag of SAI: no_use: This MBSFN area information is not used. use: This MBSFN area information is used.

SAI

This is the MBMS Service Area Identity (MBMS SAI). MBMS Service Area (MBMS SA) is defined in 3GPP TS 23.246. MBMS SA has a MBMS SAI or several MBMS SAIs. A cell has a MBMS SAI or several MBMS SAIs because it belongs to a MBMS


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Description SA or several MBMS SAs.


Type Name

Type Description

RRC Message

MBMSInterestIndication

Counted when eNB has received the RRC MBMSInterestIndication message from UE.


REFERENCE [1] 3GPP TS36.331 Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification (Rel.11)


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LTE-SV0514, Adaptive Delay Reduction for eMBMS INTRODUCTION Due to the MCCH modification period, for example, 512 ms or 1024 ms, data transmission of an MBMS session can be delayed longer than 5.12 second. This delay occurs in eMBMS sessions only because the eMBMS data transmission needs to be synchronized among eNBs unlike unicast traffic. The delay results in poor quality of experience of eMBMS UEs because there is a large time gap between video on device and live scene in the stadium. In case of PTT over eMBMS, the delay is significant. This feature reduces the delay by discarding data packets buffered at eNBs, which results in pulling up the time from the perspective of UE. This feature can be enabled for live broadcasting or PTT over eMBMS.

BENEFIT In live broadcasting service, the time gap between the video played in device and the live scene in the stadium is eliminated and the user can watch the synchronized video in the stadium.

In voice service such as Push-To-Talk, the voice messages can be delivered without unnecessary delay at eNB.

DEPENDENCY AND LIMITATION Dependency This feature can be enabled in Samsung MCE and eNB. Limitation If the MCE does not get the delay information from the eNB that is located in distance from BMSC, the eNB might not transmit MBMS data for the delay reduction session due to the excessive time shifting.

The eNB might not transmit MBMS data that arrives lately. Time shift can occur only when the synchronization sequence length of session is less than 1.5 seconds. Otherwise, the eNB discards MBMS packets during the first 5 seconds. However, the MCE and eNB cannot reduce the delay due to the insufficient synchronization sequence learning time.

Adaptive Delay Reduction (ADR) feature must be enabled when all the eNBs connected to the MCE supports ADR feature.


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There can be eMBMS interference at the edge when two or more MCEs setup ADR session for the same eMBMS session, even though they coordinate resource allocation through LSM, such as RFAP.

FEATURE DESCRIPTION When the MBMS session starts, the BMSC transmits MBMS data unit periodically according to specified synchronization sequence. If the data to be transmitted does not exist, since void packet, without user data, along with timestamp are transmitted. The eNB could receive timestamp increasing packet successively. It transmits the packet at the calculated time according to timestamp + offset base. If the packet is empty, data is not be transmitted for the corresponding time period. Therefore, from the moment of first timestamp binding to corresponding SFN, all the packets in the session have same delay until the end of the session. During packet transmission in the session, to prevent delay, the eNB discards the buffered packets and transmits recently arrived packet. This is similar to eliminating the front of a movie, to make earlier showing time. All eNBs must be synchronized between transmitting data. So, the MCE makes decision of the moment to discard the packet and transmission starting and send notice to all broadcasting target eNBs. The adaptive delay reduction function is performed through gap control between SFN and timestamp, which is specified in the MBMS data packet. For example, as shown in the figure below, if the offset value is 512, the arrived packet (with timestamp value = 6) near SFN = 512 is transmitted on SFN = 518. This causes 60 ms packet delay. If the offset value is changed to 508, the packet (with timestamp = 6) is transmitted on SFN = 514. As a result, delays can be reduced by 40 ms.

Figure below depicts the call procedure among the eNB, MCE, and BMSC. Steps 4 to 5 are executed for the MBMS session configured as Minimum_Time_To_MBMS_Data_Tansfer = 0.


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BMSC Functionality BMSC transmits MBMS data after SESSION START message transmission to MCE after the time specified on Minimum_Time_to_MBMS_Data_Transfer. During this time, all eNBs belonging to MBMS service area perform session configuration, radio resource configuration, and multicast joining to prepare MBMS data transmission. For this feature, the BMSC provides the following functions:

When transmitting SESSION START message, the BMSC sets up Time_to_MBMS_Data_Transfer = 0 for the live streaming session to minimize the delay. Then, after sending SESSION START, the BMSC transmits the MBMS data packet or empty packet (Type 0).

Synchronization sequence length of a session, subject to delay reduction, must be less than 1.5 second. If the length is greater than 1.5 second, the value of Minimum_Time_to_MBMS_Data_Transfer must not set to 0. If this session is assigned as the session subject to delay reduction, even though initially transmitted MBMS packet is lost, time is not shifted. The MBMS data sent during initial session is lost when time is shifted. This loss occurs for approximately five seconds, until MCE completes the delay reduction procedure following the start message transmission. The packets received by the eNB after that are not be lost due to time shift function. However, packets arriving late by backhaul network delay are discarded according to the normal eMBMS operation.


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MCE Functionality The MCE performs the adaptive delay reduction function for the session configured as Time_to_MBMS_Data_Transfer = 0. After receiving the SESSION START REQUEST message from MME, the procedures of this and SCHEDULING INFORMATION messages are transmitted to the target eNB as same as normal eMBMS session. For the adaptive delay reduction enabled session, the eNB is notified that the corresponding session is delay reduction session through SESSION START message. Based on received DELAY TIME INFORMATION (SessionID, Offset, and Synchronization Sequence Length) from each eNB, the MCE detects eNB which was most delayed receiving MBMS data. The time shift value is determined according to the late eNB. The MCE transmits the final offset value to all eNBs to make time shift. The time shift is applied the same way even when the eNB is restarted.

eNB Functionality For the delay reduction function enabled session, the eNB discards the MBMS data upon receiving the SESSION START REQUEST message until receiving the TIME SHIFT REQUEST. The synchronization sequence length can be acquired through synchronization sequence learning for the corresponding session. The eNB transmits the synchronization sequence length and SFN (offset) when zero timestamp received and Session ID (MCE-MBMS-M2AP-ID) to MCE through the DELAY TIME INFORMATION message. When the eNB receives the TIME SHIFT REQUEST message, it modifies the timestamp of each packet to make radio transmission time shift.

SYSTEM OPERATION How to Activate Execute the command CHG-MBMSDELAY-INF to configure „ADAPTIVE_DELAY_REDUCTION_USE‟ as to „On‟ or „Off‟.

Execute the command RTRV-MBMSDELAY-INF to retrieve the existing configuration settings.

Key Parameters CHG-ENBPDCP-INF/RTRV-ENBPDCP-INF Parameter

Description

DB_INDEX

This specifies the index of this tuple.

ADAPTIVE_DELAY_REDUCT ION_USE

This parameter represents On/Off of the adaptive delay reduction functionality.


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Counters and KPIs Family Name MBMS_ENB_SYNC has two counters related to this feature. Family Display name

Type

Description

DroppedSyncPduCount_ADR

Integer Range:0~2147483647

The cumulated number of SYNC PDU discarded by the Adaptive Delay Reduction functionality.

DroppedSyncPduByte_ADR

Integer Range:0~2147483647

The cumulated bytes of SYNC PDU discarded by the Adaptive Delay Reduction functionality.

REFERENCE N/A


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LTE-SV0515, eMBMS Session Monitoring INTRODUCTION Unlike unicast sessions, a MBMS session must be kept very long time. There is no feedback from UEs whether they receive the MBMS data successfully. Therefore, a service monitoring tool is provided to monitor whether MBMS data is normally broadcasted. With this feature, you can monitor each session based on TMGI. Provided information includes the total number of transmitted, received, discarded, and delayed packets, radio usage rate, and a plurality of configuration information. Due to the hardware resource limitation, LSM provides a limited number of sessions that operator can monitor at the same time.

BENEFIT Operator can monitor eMBMS session and check the status and quality of eMBMS service.

DEPENDENCY AND LIMITATION Dependency This feature can only be enabled with Samsung eNB, MCE, and LSM Limitation You can monitor up to 20 sessions at the same time. However, a cell provides the session monitoring information of up to 16 sessions.

The information is updated at every 2.56 seconds. Even in case of the same session, the displayed information can be different at a monitoring moment between different cells or between eNB and MBMSGW/BMSC because of different delays. In addition, statistics from RLC and GTP layers cannot be exactly matched at a specific moment because of packets in traversal or different time sources used.


eMBMS Session Monitoring. eMBMS Session Summary Log. eMBMS Service Status Report. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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eMBMS Session Monitoring This feature checks the service quality and the normality of the service status for each session from BMSC. The eMBMS data is transmitted by BMSC to the eNB that broadcasts this data via MBMS GW. You can check the information listed on the table below by selecting a specific cell and session (TMGI) through LSM. You can check the information for up to 20 cells or 20 sessions at the same time. The corresponding information is automatically updated at every 2.56 seconds. When a session meets the condition, is created, the information is automatically displayed on the screen.

Input: List of ECGI and TMGI Output: Listed in the table below. The following information is provided per cell: TMGI. Number

Items

Level

Description

Collection Entity

1

Start Time

Per TMGI

The time that eNB has opened MTCH channel of the session (TMGI).

Call Controller (eNB)

2

MBSFN Synchronization Area ID

Per TMGI

MBSFN synchronization area ID of the specified cell.


3

MBMS Service Area ID

Per TMGI

MBMS service area ID of the specified TMGI.


4

MBSFN Area ID

Per TMGI

MBSFN area ID of the specified cell.


5

PMCH

Per TMGI

PMCH ID that corresponds to the specified TMGI.


6

MTCH

Per TMGI

MTCH ID that corresponds to the specified TMGI.


7

Data MCS Level

Per TMGI

Data MCS level of the PMCH where the specified TMGI belongs to.


8

Singnalling MCS Level

Per TMGI

Signaling MCS level of the PMCH where the specified TMGI belongs to.


9

RX Packets (Type 0)

Per TMGI

The total number of Type 0 packets that eNB has received from MBMS after a session started of the specified TMGI.

SYNC Handler (eNB)

10

RX Packets (Type 1)

Per TMGI


SYNC Handler (eNB)

11

RX Packets (Type 3)

Per TMGI


SYNC Handler (eNB)

12

TX Packets

Per TMGI

The total number of packets that SYNC Handler has transmitted to each cell of the corresponding eNB after a session started of the specified TMGI.

SYNC Handler (eNB)

13

Discarded Packets (Empty)

Per TMGI

The total number of packets including summary packet that have been discarded by SYNC handler, after a session started of the specified TMGI.

SYNC Handler (eNB)

14

Discarded Packets (Lost)

Per TMGI

The total number of the discarded packets due to some packets that has not been

SYNC Handler (eNB)


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Items

Level

Description received among the packets that SYNC handler has received within the synchronization sequence after a session started of the specified TMGI.

Collection Entity

15

Discarded Packets (Others)

Per TMGI

The total number of packets that have been discarded by SYNC Handler for reasons other than empty and lost after a session started of the specified TMGI. For instance, when multicast packets are received while the RLC is not ready.

SYNC Handler (eNB)

16

RX SSEQ

Per TMGI

The total number of synchronization sequences that SYNC handler has received after a session started of the specified TMGI.

SYNC Handler (eNB)

17

TX SSEQ

Per TMGI

The total number of synchronization sequences that SYNC handler has transmitted to each cell after a session started of the specified TMGI.

SYNC Handler (eNB)

18

Discarded SSEQ

Per TMGI

The total number of synchronization sequences that have been discarded by SYNC handler after a session started of the specified TMGI.

SYNC Handler (eNB)

19

Delayed RX SSEQ

Per TMGI

After a session started of the specified TMGI, the packets that belong to the next synchronization sequence will be received. The total numbers of synchronization sequences that have been transmitted to each cell after all delayed packets of the previous synchronization sequence are received.

SYNC Handler (eNB)

20

RX Packets (RLC)

Per TMGI

The total number of packets that RLC has received after a session started of the specified TMGI.

RLC (eNB)

21

TX Packets (RLC)

Per TMGI

The total number of packets that have been transmitted by RLC after a session started of the specified TMGI.

RLC (eNB)

22

Control Packets

Per TMGI

The total number of packets that have been discarded in RLC due to no payload, after a session started of the specified TMGI. For example, Type 0 or Type 3 packets.

RLC (eNB)

23

Discarded Packets (Late Arrival)

Per TMGI

The total number of packets that have been discarded in RLC due to late arrival after a session started of the specified TMGI (control packets excluded).

RLC (eNB)

23-1

Discarded Packets (Insufficient Radio Resource)

Per TMGI

The number of packets that have been discarded without being transmitted due to the lack of radio resources for a session of the specified TMGI.

RLC (eNB)

24

Discarded Packets (Others)

Per TMGI

The total number of packets that have been discarded in RLC for the reasons other than empty, late arrival, lack of radio resources after a session started of the specified TMGI (control packets excluded).

RLC (eNB)

25

Throughput (Total Bytes x

Per TMGI

Calculates the throughput by counting the total bytes that have been transmitted from

RLC (eNB)


866


Items 8/Period)

Level

Description RLC for the period (collecting period: 2.56 seconds). The unit is Kbps.

Collection Entity

26

Buffer Usage

Per Cell

The entire buffer usage for eMBMS in a specified cell at the moment of collecting statistic information. Number of occupied buffers/total buffers x 100.

RLC (eNB)

27

PRB Usage

Per PMCH

The amount of the PRB usage used in the PMCH among the total radio resources assigned to PMCH, where the TMGI belongs to the statistics information during collecting period. Number of PRBs used for the PMCH/Number of PRBs configured for the PMCH.

MAC (eNB)

eMBMS Session Summary Log If an eMBMS session is terminated normally or abnormally, the eNB collects information for the session from each cell and transmits to the LSM. This information is saved in the LSM for certain period and discarded automatically. If traffic volume is large between eNB and LSM, you can remove the normal termination cases. The eMBMS session summary log information includes all the counting information for eMBMS session monitoring on the above tables and the following information is collected additionally. The eMBMS session can last up to 19 days according to its standard. However, the eNB closes the session summary log periodically and reports it to LSM. Number

Items

Level

Description

Collection Entity

1~27

-

-

Refer to 1 to 27 in eMBMS session monitoring.

-

28

End Time

Per TMGI

Session stop time of the specified TMGI.


eMBMS Service Status Report You can identify the current eMBMS service area through the LSM. You can check the MBSFN area list that supports each MBMS service area and can retrieve the following information of each MBSFN area:

Input: MCE and MBSFN area ID. Output: Listed in the table below. The following information is provided per MBSFN area. Number

Items

Level

Description

Collection Entity

1

Total Number of eMBMS eNBs

Per MBSFN Area

The total number of eNBs registered to MCE through M2 Setup among the eNBs included in the MBSFN area of the specified MCE.

MCE


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Items

Level

Description

Collection Entity

2

Total Number of eMBMS Cells

Per MBSFN Aera

The total number of cells that were set to provide eMBMS service to eNB through M2 Setup Response among the eNBs included in the MBSFN area of the specified MCE.

MCE

3

Total Number of Reserved Cells

Per MBSFN Area

The total number of cells that were notified as reserved cells to eNB through M2 Setup Response among the eNBs included in the MBSFN area of the specified MCE.

MCE

4

Subframe Allocation

Per MBSFN Area

Sub-frames that were set for eMBMS in the MBSFN area of the specified MCE (SIB2 information).

MCE

5

RFAP

Per MBSFN Area

Radio frame allocation pattern that was set for eMBMS in the MBSFN area of the specified MCE.

MCE

6

Number of PMCHs

Per MBSFN Area

The total number of the PMCHs that is providing service in the MBSFN area (up to 15).

MCE

7

PMCH Resources

Per PMCH, Per MBSFN Area

Resources assigned to the PMCH among the eMBMS sub-frame resources assigned to the MBSFN area.

MCE

8

Number of MTCHs

Per PMCH, Per MBSFN Area

The total number of MTCHs provided in the MBSFN area per PMCH.

MCE

SYSTEM OPERATION How to Activate Execute the command RTRV-SSL-CTRL to retrieve the existing configuration settings for Session Summary Log (SSL).

Execute the command CHG-SSL-CTRL to configure the settings for SSL. Execute the command RTRV-MCERSC-STS to retrieve the resource status of MCE.

Key Parameters CHG-SSL-CTRL/RTRV-SSL-CTRL Parameter

Description

DB_INDEX

Index of this relation.

MBMS_SSL_CREATE_CONDITION

Deciding value how to apply SSL.

RTRV-MCERSC-STS Parameter

Description

MBSFN_AREA_ID

Index of Multimedia Broadcast Single Frequency Network or Multicast Broadcast Single Frequency Network (MBSFN) area.

TOT_ENBS

Total number of eNBs that have connected with MCE through


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Description M2 interface.

TOT_CELLS

Total number of eMBMS service cells that have connected with MCE through M2 interface except reserved cell.

TOT_REV_CELLS

Total number of reserved cells that have still connected with MCE through M2 interface in the MBSFN area.

RFAP

Radio frame allocation period for the MBSFN area.

SUBFRAME_ALLOC[12]

MBSFN sub-frame configuration (sub-frame allocation: one frame item) in SIB2.

NUM_PMCH

Total number of Physical Multicast Channels (PMCHs) allocated for eMBMS.

SF_ALLOC_END

Ratio of the sub-frame resources allocated by MBSFN area and used actually in PMCH.

N_MTCH_P0

Total number of MTCHs per 0-th PMCH provided by the MBSFN area.

N_MTCH_P14

Total number of MTCHs per 14-th PMCH provided by the MBSFN area.


REFERENCE N/A


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LTE-SV0516, eMBMS Unicast Fallback (Dynamic Switching between Unicast and Broadcast) INTRODUCTION Broadcast transmission has an advantage of efficient usage of radio resources by transmitting the same data to multiple users. When the number of users is a little, however, it may rather be a waste of resources. This means that it is necessary to switch between unicast and broadcast according to the number of users for efficient utilization of radio resources. This feature allows operator to obtain high spectral efficiency by switching from unicast to broadcast or from broadcast to unicast dynamically based on the number of the RRC-connected UEs.

BENEFIT eMBMS radio resources can be used for unicast service when there is only a little number of eMBMS users under the coverage.

DEPENDENCY Required Network Elements MME, MCE, BMSC Streaming server is needed to support the same contents of MBMS with unicast

Interface & Protocols M2 I/F

Prerequisite Features LTE-SV0502 (MBMS Counting) needs to be activated to make this feature functional. eMBMS Basic Function (LTE-SV0501), Multicell and Multicast Coordination (MCE) (LTE-SV0503), eMBMS Resource Allocation (LTESV0504) are basically needed for eMBMS.

Others R-12 UE that supports Dynmaic switching between Unicast and Broadcast (UEs which do not support this feature cannot switch between Unicast and Broadcast automatically when MBMS sessions are suspended or resumed).

LIMITATION Software package version of eNBs and MCEs shall not be less than SLR 6.0.0.


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SYSTEM IMPACT Interdependencies between Features eMBMS Unicast Fallback is not activated without activation of MBMS Counting (LTE-SV0502) in EMS. Interfaces MBMS Suspension Notification List IE of MBMS Scheduling Information message in M2AP interface to notify eNB of suspended sessions is added.

FEATURE DESCRIPTION MBMS Unicast Fallback function makes the MBMS bearers be suspended or resumed based on MBMS Counting. When the number of connected mode UEs is smaller than a threshold value (Threshold_suspension), the MBMS bearer is suspended and its radio resources are released. When the number of connected mode UEs is larger than another threshold value (Threshold_resumption), the MBMS bearer is resumed and its radio resources are reallocated. This function consists of three stages as follows.

MBMS Counting Switching Decision eMBMS Service Suspension and Resumption MBMS Counting By MBMS Counting function, MCE obtains the number of connected mode UEs which are receiving or interested in receiving a service within an MBSFN area.

Switching Decision MCE determines MBMS session suspension or resumption with the following rule.

The condition when the i-th MBMS session being served within an MBSFN area is suspended: UE_Counting(i) <= Threshold_suspension.

The condition when the i-th MBMS session being served within an MBSFN area is resumed: UE_Counting(i) >= Threshold_resumption.

To avoid ping-pong effect, the two parameters, Threshold_suspension and Threshold_resumption, should be configured to meet the condition Threshold_resumption > Threshold_suspension. Where UE_Counting(i) is the number of connected mode UEs which are receiving or interested in receiving the i-th MBMS session within an MBSFN area.

eMBMS Service Suspension and Resumption Function MCE activates eMBMS Service Suspension function or Resumption function based on Switching Decision.


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Suspension Function: MCE requests the eNB that it releases the allocated RAN resources, leaves the IP multicast, shall update the MCCH information and shall suspend the MBSFN transmission while keeping the MBMS context for that session. Although all sessions are suspended, MCCH is transmitted and Radio Frame Allocation Period (RFAP) is changed to rf32 which is the maximum value to minimize the amount of MBSFN subframes.

Resumption Function: MCE requests the eNB that it shall allocate the RAN resources, shall send the MCCH change notification, shall update the MCCH information, shall resume the MBSFN transmission and shall join IP multicast. Figure below depicts the call flow for eMBMS service suspension and resumption function.

1 MBMS Counting Procedure is activated. 2 Whether to suspend or resume for each session is determined at MCE. 3 The updated scheduling information of MBMS radio resources according to the decision of session suspension or resumption is transferred from MCE to eNB with MBMSSchedulingInformation message.

4 eNB notifies UEs for the change of SystemInformationBlockType2 message which includes the updated MBSFN-SusbframeConfig IE and broadcasts SystemInformationBlockType2. SystemInformationBlockType13 is also broadcasted to acknowledge MCCH configuration information.

5 The updated MBSFN Area Configuration information IE according to the decision of session suspension or resumption is transmitted to UE through MCCH.



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COUNTING_ENABLE must be On in RTRV-MCE-COUNTINGINFO. Activation Procedure Run CHG-MBMS-FALLBACKCTRL and set UNICAST_FALLBACK_ENABLE as On of each MBSFN_AREA_ID. Deactivation Procedure Run CHG-MBMS-FALLBACKCTRL and set UNICAST_FALLBACK_ENABLE as Off of each MBSFN_AREA_ID.

Key Parameters This section describes the key parameters for activation, deactivation, and configuration of the feature. Activation/Deactivation Parameter To activate or deactivate the feature, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MBMS-FALLBACKCTRL/RTRV-MBMSFALLBACKCTRL Parameter

Description

UNICAST_FALLBACK_ENABLE

This parameter is used for enabling/disabling of the functionality of 'Unicast fallback'.

Configuration Parameter To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of CHG-MBMS-FALLBACKCTRL/RTRV-MBMSFALLBACKCTRL Parameter

Description

SUSPENSION_THRESHOLD

This field is threshold of 'suspension (multicast off)' trigger condition.

RESUMPTION_THRESHOLD

This field is threshold of 'resumption (multicast on)' trigger condition.


REFERENCE [1] 3GPP TS 36.300 Overall description; Stage 2 (Release 12) eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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[2] 3GPP TS 36.331 Radio Resource Control (RRC); Protocol specification (Release 12) [3] 3GPP TS 36.443 M2 Application Protocl (M2AP) (Release 12)


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LTE-SV0517, eMBMS Service Restoration INTRODUCTION This feature recovers the eMBMS sessions when the eNB, MCE, or MME fails. When MME fails, the session context moves to another MME. The MCE reassociates the existing eMBMS sessions with the new MME, which requests MBMS Session Start Request message with Re-establishment Indication flag. When the MCE restarts, it performs M3 setup and sends the M3 Reset message to the MME. The MME sends the original eMBMS Session Start message to recover the sessions. When the M3 link fails, the MCE deletes all the related eMBMS sessions and tries to setup M3 repeatedly. As soon as the M3 setup is completed, the MCE sends the M3 Reset message to the MME. The MCE can be connected to a maximum of 16 MMEs. However, MCE expects that the same MME controls the same MBMS sessions, which means that the MCE rejects any duplicate MBMS Session Start Request message from other MMEs without the Re-establishment Indication flag.

BENEFIT This feature enables MBMS service to continue even when the MME, MCE, or M3 path fails.

DEPENDENCY AND LIMITATION Dependency MME that supports 3GPP release 12. Limitation A maximum of 16 MMEs can be supported.


eMBMS Service Restoration When eNB Fails. MME Restoration Support. MCE Restoration.


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eMBMS Service Restoration When eNB Fails The MCE does not delete the MBMS session information in the event of STCP Keep-Alive message failure. When the eNB reboots, the MCE transmits all the MBMS session information as soon as the eNB and MCE setup the M2 connection. As eNBs in the same MBSFN area use the synchronized SFN and the same timestamp offset value for each MBMS session, the rebooted eNB can keep the restored MBMS sessions synchronized with neighbor eNBs. Figure below depicts the eNB failure case of the centralized MCE.

The eNB treats the M2 setup as normal, as it cannot differentiate from normal start to recovered session. The MCE does not flag any non-standard information to the eNB.


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MME Restoration Support The MME requests the eMBMS Session Start Request message and the eMBMS session associated with the MME. When MME fails, another MME can send this message with the Session Re-establishment Indication flag when the primary MME fails. Then, the MCE re-associates the eMBMS session to the secondary MME that requests the session re-establishment.

The MBMS Session Start Request message with Re-establishment Indication flag can differ from the existing. In this case, the MCE sends the MBMS Session Update message to all eNBs of in corresponding MBMS service area.

MCE Restoration When the MCE restarts or detects a failure in the M3 link, it sets up M3 and sends the M3 Reset message to MME. Then, the MME sends the MBMS Session Start message to the MCE. When the M3 link fails, the MCE releases all the managed eMBMS sessions.

SYSTEM OPERATION How to Activate 

This feature is basically enabled and operator cannot disable

Dependency with other feature, limitation and prerequisite: RTRV-MCECONNPARA/CHG-MCECONN-PARA: MME_FAILOVER_TIMER.


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Counters and KPIs eMBMS MCE session-related statistics have the following items. You can retrieve them by the MME index. Node restoration-related parts cannot be checked, however, you can see that the MBMS_SESSION_SETUP statistics of the other MME index are increasing. MBMS_SESSION_SETUP: SessionStartAtt, SessionStartSucc, and so on. Family Name

Counter Name

Description

MBMS_SESSION_SETUP

SessionStartAtt

Count of M3 session start attempts transmitted by the MME.

SessionStartSucc

Count of M3 session start successes transmitted by the MCE.

SessionStartFail_CP_CAPA_CAC_F AIL

M3 session start failure count. A failure is due to the CAC by MCE.

SessionStartFail_M3AP_CU_FAIL

M3 session start failure count. A failure is due to the specified cause in specification TS36.444.

SessionStartFail_M3AP_LINK_FAIL

M3 session start failure count. A failure is due to SCTP link failure.

SessionStopAtt

Count of M3 MBMS session stop received by the MCE.

SessionStopSucc

Count of M3 MBMS session stop successes transmitted by the MCE.

SessionStopFail_CP_CC_FAIL

Count of failure of M3 MBMS Session Stop. This failure is due to reception of RESET during the Session Strop procedure or block restart, and so on.

SessionStopFail_M3AP_LINK_FAIL

Count of failure of M3 MBMS Session Stop. This failure is due to SCTP link failure.

REFERENCE [1] 3GPP TS 23.007, Restoration procedures


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LTE-SV1400, TCP UL Congestion Control INTRODUCTION When UpLink (UL) is congested, Transmission Control Protocol (TCP) DownLink (DL) throughput is limited because TCP DL session requires UL resource to send acknowledge. This feature improves TCP DL throughput when UL is congested by improving the structure of packet processing in eNB.

BENEFIT DL throughput degradation due to UL congestion can be prevented.

DEPENDENCY None

LIMITATION None

SYSTEM IMPACT FEATURE DESCRIPTION Basic concept When UL is congested, TCP DL throughput is limited because TCP DL session requires UL resource to send acknowledge. Let A, B, and C to be defined as follows:

A: UL air resource share of TCP UL session (Data) B: UL air resource share of TCP DL session (ACK). A + B = 100 % C: the ratio of throughput for ACK packets over TCP packets (C ≈ TCP ACK size/(TCP packet size × delayed ACK parameter)) Then, DL throughput is limited to the minimum of {DL peak throughput, UL peak throughput × (A × C + B/C)} Thus, improving TCP DL throughput can be achieved by increasing B.


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Operation When UL is congested, eNB discards some data packets of TCP UL session to expedite the transmission of ACK packets of TCP DL session. By doing so, the amount of data packets which belong to TCP UL session decreases as a result of congestion control. Since only data packets in TCP UL session are discarded, the amount of packets which belong to TCP DL session will continue to increase. Thus, TCP DL throughput can increase along with B.


How to activate This feature run if PLDUlPowerControlParamLogic::reserved1 = 1. If PLDUlPowerControlParamLogic::reserved1 = 0, this feature can be disabled.



REFERENCE None


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Chapter 10 System Test and Analysis LTE-OM9001, Cell Traffic Trace INTRODUCTION This feature provides detailed information at call level on all UEs in a specific cell. The traceable interfaces are UE-Associated S1, X2 and RRC. This trace result is transmitted to the LSM or the Trace Collection Entity (TCE) server.

BENEFIT This feature allows operator to analyze all the signaling messages transmitting and receiving in a specific cell, which can be used for troubleshooting.

DEPENDENCY Required Network Elements MME, TCE


Prerequisite Features Feature ID (Feature Name): LTE-OM9003 (To collect UE Throguhput and RF information in this feature)

LIMITATION LSM can act as TCE server but stores simultaneously trace results from up to 6 cells in E-UTRAN system.

In case of CPU overload status, tracing can be suspended to prevent the negative impact on the service users.

SYSTEM IMPACT Interfaces Added or modified trace information may affect interface with External Server, so it is required to discuss in advance.


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FEATURE DESCRIPTION Samsung eNB provides 3GPP standard (TS 32.422 & 32.423) based Subscriber and Equipment Trace. This feature performs tracing signalling interface messages on all calls in the specific cell. Operator can control the cell traffic trace using cell ID through LSM. If trace results are generated, eNB reports it to TCE.

When several PLMNs are supported in the RAN, for starting Trace the eNB shall only select UEs where the pLMNTarget = selectedPLMN-Identity that the UE includes in RRCConnectionSetup message 3GPP TS 36.331. Management based trace procedure is as follows:

Management Based Trace Activation (New Call)

Management Based Trace Activation (Call undergoing call setup)


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Management Based Trace Activation (Existing Call)

Management Based Trace Deactivation


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If a call ends normally by sending a RRC Connection Release message to the UE, the trace recording session for that call is ended. To stop the tracing for the cell, the deactivate trace message is sent to the eNB through the LSM. Polling scheme for UE throughput and RF information in this feature (Refer to the LTE-OM9003)

Operator can collect UE throughput and RF information using this trace scheduling function basically.

When new attach/HO calls come, eNB starts tracing signaling messages, UE throughput and RF inroamtion upto the limited number of UEs on a cell.


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Time

UE1 in

UE6 in

UE7 in

UE(k) in

UE1 out

UE(k+1) in

UE(x) in Signaling message + UE throughput and RF information trace UE(x) in only Signaling message trace

Round-Robin Scheme for UE throughput and RF information in this feature (refer to the LTE-OM9003)

Operator can collect the UE throughput and RF information for all UEs using this trace scheduling function.

Every trace report period, eNB selects and starts tracing the UE throughput and RF information for the limited number of UEs on a cell. Trace report period UE1~6 trace

Time UE7~12 trace

UE(k)~(k+5) trace

UE1~6 trace

UE1 UE2

UE6

UE7 UE8

UE12 UE(k) UE(k+1)

UE(k+5)


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How to Activate This section provides the information that you need to configure the feature. Precondition There are no specific preconditions to activate this feature Activation Procedure 1 In LSM, select Performance Management >> Call Trace

2 Select Register 3 Select Management based trace for trace type 4 Input the following parameters oTarget eNB oList of interface: S1, X2, Uu oDepth: Minimum, Medium, and Maximum oTarget cell ID oTCE_IP oTarget MCC oTarget MNC oChoose Trace Overload Control Flag Deactivation Procedure 1 In LSM, selec Performance Managemnet >> Call Trace

2 Select a trace in session 3 Click stop Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-TCE-LIST/CHG-TCE-LIST/CRTE-TCELIST/DLT-TCE-LIST Parameter

Description

tceType

This parameter represents the TCE server type and has to one of three below values. standAlone: TCE Server is standAlone Type. lsmEmbedded: TCE Server is embedded in LSM smartSon: TCE Server is for Smart SON server

Parameter Descriptions of RTRV-ENBOVLD-CTRL/CHG-ENBOVLD-CTRL eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

traceResumeCondition

The Condition to resume Call Trace in eNB

traceDisableCondition

The Condition to disable Call Trace in eNB

Parameter Descriptions of RTRV-TCE-STS Parameter

Description

tceIndex

TCE Index

tceId

TCE ID

Status

TCP connection status retrieved from the kernel. The status shall be represented as either connected or disconnected


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP) [3] 3GPP TS32.422 Telecommunication management; Subscriber and equepment trace; Trace control and configuration management [4] 3GPP TS32.423 Telecommunication management; Subscriber and equepment trace; Trace data definition and management


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LTE-OM9002, Subscriber and Equipment Trace INTRODUCTION Subscriber and equipment trace provide detailed information at call level on one or more specific mobile(s). This data is transmitted to the TCE server.

BENEFIT This feature allows operator to analyze the signaling messages transmitting and receiving through S1-MME, X2 and Uu interfaces for a designated user, which can be used for troubleshooting.



Prerequisite Features Feature ID (Feature Name): LTE-OM9003 (To collect UE Throguhput and RF information in this feature)

LIMITATION In case of CPU overload status, tracing can be suspended to prevent the negative impact on the service users.

An eNB can support the signaling based trace upto 100UEs.

SYSTEM IMPACT Interfaces Added or modified trace information may affect interface with External Server, so it is required to discuss in advance.

FEATURE DESCRIPTION Samsung eNB provides 3GPP standard (TS 32.422 & 32.423) based Subscriber and Equipment Trace. This feature performs tracing signalling interface messages on a specific UE. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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This feature supports mobility. If the Trace Activation IE is contained in the Initial Context Setup Request message, or Trace Start message is received from the MME, the eNB starts a trace for the call. If the Trace Activation IE is contained in the Handover Request message received from the source eNB or the MME in case of X2 or S1 Handover, the eNB starts a trace for the call. If trace results are generated, eNB reports it to TCE.

Signaling based trace procedure is as follows:

Signaling Based Trace Activation


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Signaling based trace deactivation

If the call ends normally by sending a RRC Connection Release message to the UE, the trace is ended. To stop the tracing, the deactivate trace message is sent to the eNB through the MME.


How to Activate This section provides the information that you need to configure the feature. Precondition There are no specific preconditions to activate this feature. Activation Procedure 1 In LSM, select Performance Management >> Call Trace

2 Select Register 3 Select Signaling based trace for trace type 4 Input the following parameters oIMSI oTCE_IP oDepth: Minimum, Medium, and Maximum oSelect NE type Deactivation Procedure 1 In LSM, select Performance Managemnet >> Call Trace

2

Select a trace in session

3

Click delete


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Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature. Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-TCE-LIST/CHG-TCE-LIST/CRTE-TCELIST/DLT-TCE-LIST Parameter

Description

TCE_TYPE

This parameter represents the TCE server type and has to one of three below values. standAlone: TCE Server is standAlone Type. lsmEmbedded: TCE Server is embedded in LSM smartSon: TCE Server is for Smart SON server

Parameter Descriptions of RTRV-ENBOVLD-CTRL/CHG-ENBOVLD-CTRL Parameter

Description

TRACE_RESUME_CONDITION

The Condition to resume Call Trace in eNB

TRACE_DISABLE_CONDITION

The Condition to disable Call Trace in eNB

Parameter Descriptions of RTRV-TCE-STS Parameter

Description

TCE_INDEX

TCE Index

TCE_ID

TCE ID

STATUS

TCP connection status retrieved from the kernel. The status shall be represented as either connected or disconnected


REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 pplication Protocol (S1AP) [3] 3GPP TS32.422 Telecommunication management; Subscriber and equepment trace; Trace control and configuration management [4] 3GPP TS32.423 Telecommunication management; Subscriber and equepment trace; Trace data definition and management eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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LTE-OM9003, UE Throughput and RF information Trace INTRODUCTION UE Throughput and RF information Trace provides more detailed information than the level defined in the standard is provided. The trace result includes throughput and RF information. The operator may trigger the UE Throughput and RF information Trace through CSM. The result of the trace is transmitted to the LSM.

BENEFIT UE Throughput and RF information Trace helps to analysis traffic (throughput, and so on.) and RF information per UE.


Others Possible to designate an UE in connection with LSM-R and LSM-C

LIMITATION In case of CPU overload status, tracing can be suspended to prevent the negative impact on the service users.

This trace is performed by the cycle of 2.56 seconds. Each cell can support up to 6 UEs.

SYSTEM IMPACT Interdependencies between Features Cell Traffic Trace: This feature provides detailed information at call level on all UEs in a specific cell.

Subscriber and Equipment Trace: This feature provides detailed information at call level on one or more specific mobile(s).

Minimization of Drive Test (MDT): This feature is a standardized mechanism to collect the network performance measurements from the commercial UEs with possibly the location information. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Interfaces Added or modified trace information may affect interface with External Server, so it is required to discuss in advance.

FEATURE DESCRIPTION This is Samsung proprietary feature. From LSM or CSM, the operator can start signaling based trace. When the signaling trace starts with Vendor Specific Extention (VSE), eNB also active this feature for the call. If this feature is activated, eNB reports the RF and throughput information to TCE server periodically. (Refer LTE-OM9002 to the detail description about signaling based trace)

The following table shows the throughput information items. Classification

Item

PDCP layer (per UE/Bearer)

DL/UL PDCP Bytes Number of DL/UL Packets Number of Dropped DL/UL PDCP Packets

RLC layer (per UE/Bearer)

DL/UL RLC Bytes Number of DL/UL RLC packets Number of Lost Packet at RLC DL Number of DL Retransmitted Packets Number of Dropped Packet at RLC DL Number of Delayed Packet at RLC layer User Plane Latency

RLC layer (per cell)

Accumulated the PDCP Latency times Accumulated the number of PDCP Latency samples

MAC layer (per UE/Bearer)

DL/UL Traffic Bytes

The following table shows the RF information items. Classification MAC layer

UL Dynamic Scheduling information

Item

Description

UE’s Power Headroom

Averaged value of UE’s Power Headroom (dB)

BSR(buffer status report)

Averaged value of UE’s BSRinformation


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Item information on RBG (Radio Bearer Group)

Description (byte)

CQI (Channel Quality Indicator)

Accumulated count per CQI level

Accumulated count per wideband CQI level(0~15)

DL MCS (Modulation and coding scheme)

Accumulated statistics per DL MCS

Accumulated statistics per DL MCS (0~31)

UL MCS (Modulation and coding scheme)

Accumulated statistics per UL MCS

Accumulated statistics per UL MCS (0~31)

UL MAC BLER

UL BLER

# Blocks with CRC error / Total received MAC PDU (%)

Assigned RB count

DL Assigned RE count & RB count

DL Assigned RE count & RB count

Power setting information

TPC (Transmit power control) command count

PUCCH / PUSCH, per each command (-1, 0, 1, 3 dB: i.e., PUCCH 0  -1 dB, PUCCH 1  0 dB, PUCCH 2  1 dB, PUCCH 3  3 dB)

UE location information

Time Advance

Averaged TA (1 TA = 0.52us)

MIMO Feedback

PMI (Precoder Metric Indicator) count

PMI count per index (0~3)

RI (Rank Indicator) count

RI count Per index (0~1) UE DL RI0: # of assignment on layer 0 UE DL RI1: # of assignment on layer 1 During the collection period

DL ACK

DL Number of HARQ feedback for PUCCH (ACK)

DL NACK

DL Number of HARQ feedback for PUCCH (NACK)

DL DTX

DL Number of HARQ feedback for PUCCH (DTX)

UL ACK

UL Number of HARQ feedback for PUCCH (ACK)

UL NACK

UL Number of HARQ feedback for PUCCH (NACK)

HARQ Feedback information


How to Activate This section provides the information that you need to configure the feature. Precondition There are no specific preconditions to activate this feature.


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Activation Procedure If the Trace Activation IE with specific bit value '1' is contained in the Initial Context Setup Request (S1), Handover Request (X2) or Trace Start (S1) message received from the MME or the source eNB (HO case), the eNB starts a trace for the UE. (Refer to Trace Activation in 3GPP 36.413/423)

When the signaling trace is started with Vendor Specific Extention (VSE), the eNB active the UE Throughput and RF information Trace function.

The eNB transmits traffic and RF trace data to LSM every an period. Deactivation Procedure If the Trace Activation IE with specific bit value '0' is contained in the Initial Context Setup Request(S1), Handover Request(X2) or Trace Start(S1) message received from the MME or the source eNB(HO case), the eNB stops a trace for the UE. (Refer to Trace Activation in 3GPP 36.413/423)


Counter and KPIs The information collected as the result of the call detail trace is as follows: Counter

Description

Equip

In case of Equip, transmits the value periodically. In case of N_Equip, stops transmission.

Trace Reference ID

The trace reference ID of the phone

DL PDCP Bytes_TOTAL

No. of DL bytes transmitted from S-GW to eNB within the collection interval.

UL PDCP Bytes_TOTAL

No. of bytes transmitted to UL within the collection interval

Number of DL PDCP Packets_TOTAL

No. of user data packets transmitted to UE

Number of UL PDCP Packets_TOTAL

No. of user data packets received from UE

Number of Dropped DL PDCP Packets_TOTAL

No. of DL packets dropped from PDCP

Number of Dropped UL PDCP Packets_TOTAL

No. of UL packets dropped from PDCP

Active Bearer Count

Maximum number of the bearers being used in the interval

Bearer1 ID

RB_ID (1~8)

Bearer1 QCI

QoS ID

DL PDCP Bytes_Bearer1

No. of DL bytes transmitted from S-GW to eNB within the collection interval.

UL PDCP Bytes_Bearer1


Number of DL PDCP Packets_Bearer1


Number of UL PDCP Packets_Bearer1


Number of Dropped DL PDCP Packets_Bearer1


Number of Dropped UL PDCP Packets_Bearer1



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Description

Bearer 8 ID

RB_ID (1~8)

Bearer8 QCI

QoS ID

DL PDCP Bytes_Bearer8

DL Byte number of transmit from S-GW to eNB for gathering period

UL PDCP Bytes_Bearer8


Number of DL PDCP Packets_Bearer8


Number of UL PDCP Packets_Bearer8


Number of Dropped DL PDCP Packets_Bearer8


Number of Dropped UL PDCP Packets_Bearer8


DL RLC Bytes

DL RLC bytes transmitted within the collection interval

UL RLC Bytes

UL RLC bytes transmitted within the collection interval

Number of DL RLC Packets

DL RLC packets transmitted within the collection interval

Number of UL RLC Packets

UL RLC packets transmitted within the collection interval

Operator can check this with PM statistics in the LSM Number of Lost Packet at RLC DL

No. of lost packets in RLC DL Air section (In case of UL, impossible to measure)

Number of DL Retransmitted Packets

Possible to measure accurate losses only in the DL AM mode.

Number of Dropped Packet at RLC DL

No. of packets discarded from RLC

Number of Delayed Packet at RLC layer

No. of packets delayed from RLC

User Plane Latency

IP latency (unit = ms)

Active Bearer Count


Bearer 1 ID

RB_ID (1~8)

Bearer 1 QCI

QoS ID

DL RLC Bytes_Bearer 1


UL RLC Bytes_Bearer 1


Number of DL RLC Packets_Bearer 1


Number of UL RLC Packets_Bearer 1


Number of Lost Packet at RLC DL_Bearer 1

No. of lost packets in RLC DL Air section (In case of UL, impossible to measure)

Number of DL Retransmitted Packets_Bearer 1


Number of Dropped Packet at RLC DL_Bearer 1


Number of Delayed Packet at RLC layer_Bearer 1


User Plane Latency_Bearer 1


Bearer 8 ID

RB_ID (1~8)

Bearer 8 QCI

QoS ID

DL RLC Bytes_Bearer 8


UL RLC Bytes_Bearer 8


Number of DL RLC Packets_Bearer 8


Number of UL RLC Packets_Bearer 8


Number of Lost Packet at RLC

No. of lost packets in RLC DL Air section (In case of UL,


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Chapter 10 System Test and Analysis Counter DL_Bearer 8

Description impossible to measure)

Number of DL Retransmitted Packets_Bearer 8


Number of Dropped Packet at RLC DL_Bearer 8


Number of Delayed Packet at RLC layer_Bearer 8


User Plane Latency_Bearer 8


DL Traffic ratio  DL Traffic Bytes (Total of DRBs)

Transmitted in DL traffic bytes (integers) Aggregate of 8 DRBs (SRB information excluded)

UL Traffic ratio  UL Traffic Bytes (Total of DRBs)

Transmitted in UL traffic bytes (integers) Aggregate of 8 DRBs (SRB information excluded)

Active Bearer Count


Bearer 1 ID

RB_ID

Bearer 1 QCI

QoS ID

DL Traffic Bytes (DRB #1)

DL Traffic Bytes DRB #1

UL Traffic Bytes (DRB #1)

UL Traffic Bytes DRB #1

Bearer 8 ID

RB_ID

Bearer 8 QCI

QoS ID

DL Traffic Bytes (DRB 8)

DL Traffic Bytes DRB #8

UL Traffic Bytes (DRB 8)

UL Traffic Bytes DRB #8

The RF information included in the result of the cal detail trace is as follows: Counter

Description

Equip

In case of Equip, transmits the value periodically. In case of N_Equip, stops transmission.

Trace Reference ID

The trace reference ID of the phone

UE’s Power Headroom

The average value received during the fixed interval (dB) A negative number allowed.

BSR (buffer Status Report) information on RBG (Radio Bearer Group)

The average value received during the fixed interval (bytes)

CQI 1

Widbad CQI (1-15). Accumulated count type by CQI level in the given interval

CQI 15

-

SRS snr

Provides SRS received power as the mean of the valid value in the given interval.

DL MCS 0

Possible to six counts per cell to the maximum by phone due to the performance issue. Interval of 2.56 seconds

DL MCS 31


UL MCS 0


UL MCS 31


UL BLER

No. of CRC error-occurring blocks/no. of total blocks received (MAC PDU). (Unit: %)


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Description

DL assigned RE count

DL direction assigned RE count

DL assigned RB count

DL direction assigned RB count

UL assigned RE count

UL direction assigned RE count

UL assigned RB count

UL direction assigned RB count

TPC for PUCCH[0] (-1 dB)

Accumulated PUCCH power control statistics (Accumulated value of the TPC (transmit power control) command (-1 dB) transmission count)

TPC for PUCCH[1] (0 dB)

Accumulated PUCCH power control statistics (Accumulated value of the TPC (transmit power control) command (0 dB) transmission count)





TPC for PUSCH[0] (-1 dB)

Accumulated PUSCH power control statistics (Accumulated value of the TPC (transmit power control) command (1 dB) transmission count)

TPC for PUSCH[1] (0 dB)






Time Advance

Accumulated value of TA (Average RTD) The unit of raw data provided from MAC is the multiple of 0.52 us. In short, the actual output must be the value of 0.52 us * time advance (Unit: us).

UE  eNB PMI 0 (UL PMI 0)

Information informed by UE (Precoder Metric Indicator) index 0 UL PMI = PMI received from UE







eNB  UE PMI 0 (DL PMI 0)

Information given by the base station (Precoder Metric Indicator) index 0 PMI allocated to UE






Information given by the base station (Precoder Metric Indicator)


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Description index 3 PMI allocated to UE

eNB  UE RI 0 (UE DL RI 0)

# of assignment on layer 0 (during 2.56 sec)

eNB  UE RI 1 (UE DL RI 1)

# of assignment on layer 1 (during 2.56 sec)

UE  eNB RI 0 (UE UL RI 0)

RI requested by UE-Count by index (index 0)

UE  eNB RI 1 (UE UL RU 1)

RI requested by UE-Count by index (index 1)

DL ACK

DL Number of HARQ feedback for PUCCH (ACK)

DL NACK

DL Number of HARQ feedback for PUCCH (NACK)

DL DTX

DL Number of HARQ feedback for PUCCH (DTX)

UL ACK

UL Number of HARQ feedback for PUCCH (ACK)

UL NACK

UL Number of HARQ feedback for PUCCH (NACK)

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 [2] 3GPP TS36.413 Evolved Universal Terrestrial Radio Access Network (EUTRAN); S1 Application Protocol (S1AP) [3] 3GPP TS32.422 Telecommunication management; Subscriber and equepment trace; Trace control and configuration management [4] 3GPP TS32.423 Telecommunication management; Subscriber and equepment trace; Trace data definition and management


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LTE-OM9004, CSL (Call Summary Log) Report INTRODUCTION This feature collects the detail information for a call. The call release type, call duration, or handover information, etc. are automatically collected and transmitted to the EMS or the external server.

BENEFIT Operator can analyze the detail information of a call.

DEPENDENCY Required Network Elements External server for CSL data is required.


LIMITATION To support for all calls including normal calls, it is required to discuss in advance about expending LSM capacity or external server. (Basically, LSM can store only the CSL data of abnormal calls.)

SYSTEM IMPACT Added or modified CSL information may affect interface with External Server, so it is required to discuss in advance.

FEATURE DESCRIPTION The Call Summary Log (CSL) data is collected by eNB. When a call is setup, eNB starts to collect information for the call. If the call is released, eNB reports CSL data to the external server.


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By the configuration, eNB can support following cases:

Case 1: LSM-CSL data of abnormal calls. Case 2: LSM-CSL data of all calls. Case 3: LSM-CSL data of abnormal calls, External server-CSL data of all calls. Case 4: LSM-CSL data of all calls, External server-CSL data of all calls. Additional configurations for CSL control are as follows:

Control the CSL Ack mode to transmit the CSL data using UDP protocol (infinity, 1, 2, 3, 4, 5, 6)

Transmission protocol for CSL data result (TCP/UDP) To establish a TCP connection, operator should register the TCE server in advnace throught LSM. Otherwise, eNB reports trace results using UDP protocol by default for LSM which acts as TCE server. If operator registers the TCE server, the eNB will try to maintain the established status of the TCP connection with TCE server. eNB maintains the TCP connection using keep-alive TCP packets. If abnormal status is detected, eNB will try to re-establish the TCP connection. The CSL data includes detail information for a call. It includes a total of ten information items: call information, common item information, connection information, release information, handover information, throughput information, RF information, adjacency information, UE history information, call debugging information, RRC reestablishment information, and trace information.



Key Parameters This section describes the key parameters for activation, deactivation and configuration of the feature.


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Activation/Deactivation Parameters There are no specific parameters associated with this feature Configuration Parameters To configure the feature settings, run the associated commands and set the key parameters. Parameter Descriptions of RTRV-CSL-INF/CHG-CSL-INF Parameter

Description

DB_INDEX

Index

CSL_SERVER

The type of CSL Server.

IP_VER

The type of the IP address of the external server for which CSL data (IPV4 or IPV6) is to be collected.

CSL_SERVER_IPV4

The external CSL server's IP address in the IPv4 format.

CSL_SERVER_IPV6[16]

The external CSL server's IP address in the IPv6 format.

CSL_PORT_NUM

External Server Port Number to Receive Data

BUFFER_TIME

This parameter is for the buffering time for which eNB stores CSL data in the internal memory to reduce the network load. If the buffering time is set to 10, all of the CSL data stored in the memory is sent to the CLS server 10 seconds after the data is created. Note that the CSL data is also transmitted to the CSL server when the number of CSL data entries stored reaches 10 even within 10 seconds of data creation.

BUFFERING_COUNT

The maximum data count one-time transfer.

UDP_ACK_CONTROL

This parameter controls the number of CSL data re-transmissions when using UDP Ack method and transmitting to an external server. 0: no retransmission 1: 1 retransmission 2: 2 retransmission 3: 3 retransmission 4: 4 retransmission 5: 5 retransmission 6: 6 retransmission 7: Infinity retransmissions

PROTOCOL_SELECTION

This parameter configures which transmitting protocol to use when transmitting CSL to a external server. 0: TCP 1: UDP Ack

TCP_FILE_FORMAT

This parameter configures the CSL data file format when using TCP method and transmitting CSL to an external server. 0: CSV file format 1: Binary format



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REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2


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LTE-OM9005, Packet Loss Detection over S1 INTRODUCTION This function is used to judge the quality or status of backhaul network in the download section between Serving Gateway (S-GW) and eNB. This function is used to count the number of lost packets for a user data transmitted from S-GW to eNB and also the number of packets whose order is changed. The S-GW records the sequence number of GTP protocol for each packet and the eNB checks the sequence number of a received packet to measure statistics. The statistics is measured for each QCI. The eNB counts only downlink packets and the uplink packets are measured by the S-GW. This is for GTP, but the same function is applied even for X2 connection

BENEFIT Could be decided the quality of backhaul network.

DEPENDENCY Required Network Elements: S-GW should support GTP SN marking for S1-U DL bearer traffic.

LIMITATION eNB can count downlink packets only.


FEATURE DESCRIPTION The eNB collects the statistics for the number of lost packets and also for the number of Out of Sequence packets for downlink user packets in the GTP layer. For the objective, the eNB and S-GW adds a sequence number for each GTP packet to transmit. The eNB and S-GW checks the sequence number for a received packet. If a packet with the specific sequence number is not received, it is judged as a lost packet. If there is a packet whose order is changed based on the sequence number, the out-of-sequence packet count is increased. Each statistics must be collected per QCI to judge the effect of applying QoS in the backhaul network. The statistics collection interval is two seconds.


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SNN must be 1 in RTRV-GTP-INF to get a valid range of statistics value. S-GW can also provide GTP sequence number (optional) in GTP-u Header. Activation Procedure This feature runs automatically, and it cannot be disabled. Deactivation Procedure This feature runs automatically, and it cannot be disabled.



Type Name

Type Description

GTP_SN_QCI

GtpSnQciPeakLoss

The cumulated number of downlink GTP packets which have been regarded to be lost until the statistics collection time for each QCI.

GtpSnQciOos

The cumulated number of out of sequence downlink packets for each QCI until the statistics collection time. That is, the cumulated number of packets in which the order of the GTP sequence numbers is reversed for each QCI.

GtpSnQciDeltaLoss

The cumulated number of downlink GTP packets which are lost for each QCI.


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Chapter 10 System Test and Analysis Family Display Name

GTP_SN_ENB

Type Name

Type Description A negative value denotes that the packets which were lost in the previous collection cycle, is an out-ofsequence inflow packet for the current collection cycle.

GtpSnQciDLCnt

The cumulated number of the downlink GTP packets received until the time of counting the statistic for each QCI.

GtpSnEnbPeakLoss

The cumulated number of downlink GTP packets which have been regarded to be lost until the statistics collection time.

GtpSnEnbOos

The cumulated number of Out of Sequence downlink packets (i.e. the accumulated count of packets which order of the GTP Sequence Number is reversed)

GtpSnEnbDLCnt

The cumulated number of the downlink GTP packets received until the time of counting the statistic.

GtpSnEnbLossRate

The calculated ratio of the downlink GTP packets lost against the total packets until the time of collecting the statistics loss packet = GtpSnEnbPeakLoss total packet = GtpSnEnbDLCnt + (GtpSnEnbPeakLoss - GtpSnEnbOos).

GtpSnEnbOosRate

Total GTP Packet OOS rate per eNB

GtpSnEnbDeltaLoss

The cumulated number of downlink GTP lost packets. A negative value denotes that the packets which were lost in the previous collection cycle, is an out-ofsequence inflow packet for the current collection cycle.

GtpSnEnbDeltaLossRate

A negative value denotes that the packets which were lost in the previous collection cycle, is an out-ofsequence inflow packet for the current collection cycle.

REFERENCE [1] 3GPP TS36.300 Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2


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LTE-OM9013, Interference and Interferer Detection (TDD) INTRODUCTION TDD systems have duplex communication links where uplink is separated from downlink in time domain, in the same frequency. TD-LTE defines Guard period between downlink to uplink switching to provide protection against downlink signal becoming uplink interference. Also the guard period determines the cell range as maximum round trip delay should be less than the guard period. If there are eNBs located beyond guard period propagation distance from an eNB, the high power downlink signal from farther eNBs may cause interference on uplink channel and is known as Time of Flight (ToF) interference. ToF interference causes rise in uplink RSSI which in turn degrades receiver sensitivity. This results in reduced uplink and downlink throughput and MAPL (Maximum Allowed Path Loss) for link budget/cell coverage. Time of Flight (ToF) between eNB‟s can cause uplink interference if (1) a cochannel station has radio line-of-sight to the victim, (2) the antennas of both sites are not down tilted sufficiently to limit the radiation towards the horizon and (3) the stations are separated by more than a distance corresponding to the Gap period. 3GPP defines TDD special subframe patterns with large gap periods and such configurations can be chosen to mitigate the ToF interference. Choosing special subframe patterns with large gap period negatively impacts the cell throughput, hence operator may conservatively choose gap period to maximize cell throughput and in such cases ToF interference is expected. FDD eNBs does not have ToF interference problems as the downlink and uplink frequencies are different and they do not cause interference to each other. In a dense TD-LTE deployment, the possibility of Time of Flight (ToF) interference is high and operator requires a mechanism to identify whether a cell is suffering from ToF interference or not. A cell which is suffering from ToF interference is referred as „ToF Victim Cell‟ and the eNB/s causing the interference are referred as „ToF Aggressor Cells‟. This feature provides the capability to identify ToF victim cells.

BENEFIT Enables Time-of-Flight (ToF) interference (potential problem unique to TDD network) to be measured, detected and Operator can estimate the location of aggressor eNBs (distance range from the victim cell site).

DEPENDENCY Related Radio Technology eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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E-UTRAN (LTE) TD-LTE only (c.f. FDD-LTE does not have Special Subframe.)

Others If WiMAX/TD-LTE coexistence scheme (i.e., 1) TD-LTE frame starting point is skewed with time offset; 2) UpPTS interval and the last OFDM symbol of the second normal UL subframe in UD Config.1 are punctured) is applied, RSSI for UpPTS is not collected. RSSI OMs are supported only for UpPTS OFDM symbols and not for normal uplink subframe OFDM symbols. Hence the ToF interference on UL subframes cannot be measured using this feature. It is recommended not to configure a special subframe pattern with very low gap period which may cause interference on normal UL subframe OFDM symbols. Operator needs to configure threshold RSSI power above which the RSSI measurement is considered as ToF interference. Improper configuration of threshold RSSI power might cause false alarms or alarm being not generated. This feature provides information about the aggressor eNBs distance range from the victim eNB, and does not point out the exact aggressor eNB. Exact location of aggressor eNB can be calculated offline by using the distance range and RF planning data.

LIMITATION None


FEATURE DESCRIPTION When a cell is experiencing ToF interference, the downlink transmission of aggressor cells (DwPTS) travels more than the distance corresponding to the Gap Period and causes interference on UpPTS OFDM symbols of the victim cell. In some cases, the DwPTS can even cause interference on OFDM symbols of the uplink subframe (UL) after the UpPTS symbols. The following figure represents the UL RSSI captured in the field when ToF interference is experienced. It can be observed that ToF interference contributes to increasing the UL RSSI of UpPTS and the first OFDM symbol of normal UL subframe (the length of one OFDM symbol is equal to about 71.43us).


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Below figure shows an example of ToF interference in TDD config1, special subframe config7. In this example, DwPTS signals from aggressor eNB travels more than the distance corresponding to the Gap Period and causes interference on first UpPTS symbol of the victim eNB but not on second UpPTS symbol.


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eNB implements the RSSI OMs for UpPTS symbols 1 and 2 (13th &14th OFDM symbols of Special Subframe). In SSF#7, there are two UpPTS symbol, hence both UpPTS RSSI OMs are valid. In this example, the UpPTS symbol#1 RSSI OM will indicate high power due to ToF interference (above the ToF RSSI threshold) and the second UpPTS symbol RSSI OM will be below the threshold. LSM-R supports Threshold Crossing Alarms (TCA) using „PI-Monitoring‟ feature. Operator can configure thresholds corresponding to minor, major and critical alarms for any OMs. Depending on which threshold is crossed, eNB generates corresponding (minor/major/critical) alarm. Operator can configure minor, major, critical threshold values for the UpPTS RSSI OMs. When a cell experiences ToF interference, the RSSI of the UpPTS symbols will rise and when it is above the operator configured threshold, a ToF victim alarm will be generated. LSM-R allows the operator to flexibly choose a set of eNBs or all eNBs for configuring ToF Victim alarm. Also, separate thresholds can be configured for each of the RSSI OMs. 3GPP standard allows sounding reference signal (SRS) and random access preamble (PRACH) to be configured on UpPTS symbols. The RSSI OM generated by eNB will include all power components ie, ToF interference as well as other uplink power components which may include SRS power from the cell‟s UE or Uplink SRS interference from neighboring cells or PRACH power if PRACH is configured on UpPTS. So the ToF RSSI threshold for alarm trigger should be configured by considering all these power components which may be received in UpPTS symbols. Configuration of lower ToF RSSI threshold may cause false ToF victim alarms.

Aggressor eNB Distance estimation By trending the UpPTS RSSI OMs, the location of aggressor eNB(s) can be estimated. Consider the same example as above, in this case, the RSSI OM corresponding to first UpPTS symbol shows high RSSI indicating ToF interference and the RSSI OM corresponding to second UpPTS symbol does not show any interference. With this information, the distance of aggressor eNB can be calculated as below:



Distance corresponding to propagation of Gap Period = 2 * 2192.Ts - 624.Ts = 22.8 miles

Distance corresponding to propagation of Gap Period and One UpPTS symbol = 3 * 2192.Ts - 624.Ts = 36.1 miles. Since there is no interference on Second UpPTS symbols, the aggressor eNB(s) will be located between 22.8 miles and 36.1 miles from the victim eNB. The distance range calculation takes into account of the timing alignment offset (NTAoffset = 624.Ts) for TDD systems.


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UpPTS Punctruing Samsung supports puncturing one or both of the UpPTS symbols. If UpPTS symbols are not used for SRS and PRACH, then UpPTS symbols are said to be punctured and the interference on the punctured UpPTS symbols does not impact the cell performance. But, RSSI OM measurements are performed irrespective of whether the UpPTS symbols are punctured or not. When puncturing is turned off, then both UpPTS symbols are available for SRS transmission. Depending on whether the UpPTS symbols are punctured or not, the ToF interference distance varies. Cell performance will not have impact as long as the ToF interference is within the TOF time shown in below figures.


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The table shows the ToF distance of aggressor eNBs which may cause ToF interference on a victim eNB. SS Config

DwPTS

GP

0

6592.Ts

21936.Ts

1

19760.Ts

2

21952.Ts

3

UpPTS

UpPTS Not Punctured

UpPTS Punctured

TOF in Meter

TOF in Mile

TOF in Meter

TOF in Mile

2192.Ts

207981

129.2

229372.5

142.5

8768.Ts

2192.Ts

79476.2

49.4

100867.7

62.7

6576.Ts

2192.Ts

58084.8

36.1

79476.3

49.4

24144.Ts

4384.Ts

2192.Ts

36693.3

22.8

58084.8

36.1

4

26336.Ts

2192.Ts

2192.Ts

15301.9

9.5

36693.3

22.8

5

6592.Ts

19744.Ts

4384.Ts

186589.6

115.9

229372.5

142.5

6

19760.Ts

6576.Ts

4384.Ts

58084.8

36.1

100867.7

62.7

7

21952.Ts

4384.Ts

4384.Ts

36693.3

22.8

79476.3

49.4

8

24144.Ts

2192.Ts

4384.Ts

15301.9

9.5

58084.8

36.1

In summary, the feature operation consists of three major parts: 1) introduction of new OM for measuring per-OFDM symbol RSSI at UpPTS; 2) TCA alarm to monitor the existence of ToF interference at LSMR; 3) disabling (or puncturing) the first UpPTS OFDM symbol to avoid the ToF interference and consequently, dynamically changing SRS operation not to use the disabled UpPTS OFDM symbol.


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How to Activate This feature is basically enabled. The statistical data are collected during the eNodeB operaion and transmitted to the LSM.


Counters and KPIs For detailed information about all available counters, refer to Samsung LTE system counter description manual.

REFERENCE None


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LTE-OM9100, Key Performance Indexes INTRODUCTION Key performance indicators (KPIs) are used to monitor the quality of service provided to the end user. They are calculated using counters collected by eNodeB. Some KPIs are defined in TS32.450 while others are proprietary to Samsung. This feature provides a brief introduction to KPIs. For more detailed information, refer to Samsung LTE system counter description manual.

BENEFIT The operator can monitor the following characteristics of the service provided to the end user:

Accessibility Retainability Integrity Availability Mobility

DEPENDENCY AND LIMITATION Dependency eNodeB

REQUIREMENT RJIL-FRD-010, Reliance New Features

FEATURE DESCRIPTION ACCESSIBILITY ACCESSIBILITY Definition: These KPIs show probability for an end-user to be provided with an E-RAB at request. Probability success rate for E-RAB establishment is calculated by multiplying the probability success rates for different parts of ERAB establishment. Probability success rate of each part of E-RAB establishment is calculated as successful attempts divided by total number of attempts. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Formula Name

Description

ErabAccessibilityInit = (SumRrcConnEstabSucc/SumRrcConnEstabAtt) * (SumS1sigS1ConnEstabSucc/SumS1sigS1ConnEstabAtt) * (SumErabEstabInitSuccNbr/SumErabEstabInitAttNbr) * 100 %.

Initial E-RAB establishment success rate

ErabAccessibilityAdd = (SumErabEstabAddSuccNbr/SumErabEstabAddAttNbr) * 100 %.

Added E-RAB establishment success rate

E-RAB Connection Failure Rate = 0 if SumRrcConnEstabAtt = 0 OR SumS1sigS1ConnEstabAtt = 0 OR SumErabEstabInitAttNbr = 0. Otherwise, ERAB Connection Failure Rate = 100 (SumRrcConnEstabSucc/SumRrcConnEstabAtt) * (SumS1sigS1ConnEstabSucc/SumS1sigS1ConnEstabAtt) * (SumErabEstabInitSuccNbr/SumErabEstabInitAttNbr) * 100 %

Probability that an enduser is not provided with an E-RAB at the initial request

RACH_SUCCESS_RATE Definition: These KPIs measure RACH success rate.

Formula Name

Description

NonHoRachSuccessRate = ((RachSumConnEstabSucc + RachSumConnReEstabSucc)/(RachSumRandomlySelectedPreamblesLow + RachSumRandomlySelectedPreamblesHigh)) * 100 %

Non-Handover RACH success Rate

HoRachSuccessRate = ((RachSumIntraEnbInSucc + RachSumInterX2InSucc + RachSumInterS1InSucc)/RachSumDedicatedPreambles) * 100 %

Handover RACH Success Rate

CONN_DROP_RATE Definition: This KPI measures the ratio of number of abnormally terminated ERABs to number of successfully established E-RABs.

Formula Name

Description

ConnDropRate = CdrRelActive/(CdrSumEstabInitSuccNbr + CdrEstabAddSuccNbr)*100 %

Probability that an enduser abnormally looses an E-RAB

SUCCESS_RATE Definition: This KPI measures RRC success rate, ERAB success rate, and call drop rate based on the RRC, ERAB, CALL_DROP, and HO statistics collected.

Formula Name

Description

RrcEstabSuccessRatio = (SumRrcEstabSuccess/SumRrcEstabAttempt) * 100 %.

The average success rate of RRC_ESTAB.

ErabEstabSuccessRatio = (SumErabEstabSuccess/ SumErabEstabAttempt) * 100 %.

The average success rate of ERAB_ESTAB.

CallDropRatio = (SumCallDrop_EccbDspAuditRlcMacCallRelease + SumCallDrop_EccbRcvResetRequestFromEcmb + SumCallDrop_EccbRcvCellReleaseIndFromEcmb + SumCallDrop_EccbRadioLinkFailure +

The average call drop rate.


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Chapter 10 System Test and Analysis Name SumCallDrop_EccbDspAuditMacCallRelease + SumCallDrop_EccbArqMaxRetransmission + SumCallDrop_EccbDspAuditRlcCallRelease + SumCallDrop_EccbTmoutRrcConnectionReconfig + SumCallDrop_EccbTmoutRrcConnectionReestablish + SumCallDrop_EccbS1SctpOutOfService/SumEstabInitSuccNbr + SumInterX2InSucc + SumInterS1InSucc + SumRatInSuccUTRAN) * 100 %.

Description

CONN_TIME Definition: This KPI measures the connection setup time from RRC CONNECTION REQUEST message to INITIAL CONTEXT SETUP RESPONSE message.

Formula Name

Description

ConnSetupTime = (ConnTimeConnEstabTimeTot + ConnTimeEstabTimeTot + ConnTimeS1SigTimeTot)/(ConnTimeConnEstabTimeCnt + ConnTimeEstabTimeCnt + ConnTimeS1SigTimeCnt)

Elapsed time from transmitting RRC Connection Request to receiving Initial Context Setup Response

RETAINABILITY RETAINABILITY Definition: This KPI shows how often an end-user abnormally loses an E-RAB during the time the E-RAB is used.

Formula Name

Description

ErabRetainability = (SumRelActive/RetainSessionTimeUE) * 100.

Number of E-RABs with data in a buffer that was abnormally released, normalized with number of data session time units.

RETAINABILITY_QCI Definition: This KPI shows how often an end-user abnormally loses an E-RAB (per QCI) during the time the E-RAB is used.

Formula Name

Description

ErabRetainability = (RetainRelActive/RetainSessionTimeQci) * 100 %.

The number by dividing the E-RAB Release count by ERAB holding time.

INTEGRITY INTEGRITY Definition: These KPIs show how E-UTRAN impacts the service quality provided to an end-user.

Formula eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Chapter 10 System Test and Analysis Name

Description

EutranIpThroughput = IntegrityEutranIpThroughputTot/IntegrityEutranIpTh roughputCnt

E-UTRAN IP throughput per QCI

EutranIpLatency = IntegrityEutranIpLatencyTot/IntegrityEutranIpLatenc yCnt

E-UTRAN IP latency per QCI

CELL_THRU Definition: These KPIs measure DL/UL cell throughput and DL/UL UE throughput.

Formula Name

Description

CellThruDLAvg = CellThruDLTot/CellThruDLCnt

Average Downlink sector Throughput Counter

CellThruULAvg = CellThruULTot/CellThruULCnt

Average Uplink sector Throughput Counter

UEThruDLAvg = UEThruDLTot/UEThruDLCnt

Average Downlink UE Throughput Counter

UEThruULAvg = UEThruULTot/UEThruULCnt

Average Uplink UE Throughput Counter

CellThruDLPeak

Peak Downlink sector Throughput Counter

CellThruDLTime

Number of seconds for Downlink Throughput within a Recording Period Counter

CellThruULPeak

Number of seconds for Uplink Throughput within a Recording Period Counter

CellThruULTime

Peak Uplink sector Throughput Counter

UEThruDLPeak

Peak Downlink UE Throughput Counter

UEThruULPeak

Peak Uplink UE Throughput Counter

WEIGHTED_CQI Definition: This KPI measures average channel quality indicator (CQI) reported by UEs.

Formula Name

Description

WeightedDLReceivedCQI = SumWeightedDLReceivedCQI/SumDLReceivedCQ I

Average of channel quality indicator reported by UEs

AVAILABILITY AVAILABILITY Definition: This KPI measures the availability of E-UTRAN cell.

Formula Name

Description

EutranCellAvailability = ((CellAvailPmPeriodTimeReadCellUnavailableTime)/CellAvailPmPeriodTime ) * 100 %.

Percentage of time the cell is considered available


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CELL_CAPACITY Definition: This KPI measures the average simultaneous RRC-connected UE load per cell.

Formula Name

Description

ConnNoUEAvg = (ConnNoRrcAvg/ConnMaxCallCount) * 100 %.

The average RRC Connection Capacity rate (%) per unit time.

ConnNoUEMax

The maximum RRC Connection Capacity rate (%) per unit time.

UsageNbrRbAvg = (UsageNbrErab/UsageMaxDrbCount) * 100 %.

The average E-RAB Capacity rate (%) per unit time.

UsageNbrRbMax

The maximum E-RAB Capacity rate (%) per unit time.

ConnNoRrcAvg

The average RRC Connection per unit time.

ConnMaxCallCount

The average available call count in the cell.

UsageNbrErab

The average number of E-RAB per unit time.

UsageMaxDrbCount

The maximum available number of E-RAB in the cell.

ENB_CAPACITY Definition: This KPI measures the average simultaneous RRC-connected UE load per eNB.

Formula Name

Description

EnbConnNoUEAvg = (EnbConnNoRrcAvg/EnbMaxCallCount) * 100 %.

The average RRC Connection Capacity rate (%) per unit time.

EnbConnNoRrcAvg

The average RRC Connection per unit time.

EnbMaxCallCount

The average available call count in eNB.

MOBILITY MOBILITY Definition: These KPIs measure E-UTRAN handover success rates.

Formula Name

Description

EutranMobilityHOIntra = (sumHOIntra_Succ/sumHOIntra_Att) * 100 %.

Intra-eNB handover success rate

EutranMobilityHOX2Out = (sumHOX2Out_Succ/sumHOX2Out_Att) * 100 %.

Outgoing X2 handover success rate

EutranMobilityHOX2In = (sumHOX2In_Succ/sumHOX2In_Att) * 100 %.

Incoming X2 handover success rate

EutranMobilityHOS1Out = (sumHOS1Out_Succ/sumHOS1Out_Att) * 100 %.

Outgoing S1 handover success rate

EutranMobilityHOS1In = (sumHOS1In_Succ/sumHOS1In_Att) * 100 %.

Incoming S1 handover success rate

EutranMobilityHOInterRatHrpd = (sumHOInterRatHrpd_Succ/sumHOInterRatHrpd_A

Inter-RAT optimized HRPD handover success rate


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Chapter 10 System Test and Analysis Name tt) * 100 %.

Description

EutranMobilityHOInterRatUtranOut = (sumHOInterRatUtranOut_Succ/sumHOInterRatUtr anOut_Att) * 100 %.

Outgoing inter-RAT handover success rate

EutranMobilityHOInterRatUtranIn = (sumHOInterRatUtranIn_Succ/sumHOInterRatUtra nIn_Att) * 100 %.

Incoming inter-RAT handover success rate

EutranMobilityHOInter = ((sumHOS1Out_Succ + sumHOX2Out_Succ)/(sumHOS1Out_Att + sumHOX2Out_Att)) * 100 %.

Outgoing handover success rate to an eNB of the same frequency

VOLTE_HO_SUCCESS_RATE Definition: These KPIs measure VoLTE handover success rate.

Formula Name

Description

VoLTE_IntraHoSuccessRate = (SumVoLTE_IntraEnbSucc/SumVoLTE_IntraEnbAt t) * 100 %

VoLTE HO Intra Success rate

VoLTE_X2HoSuccessRate = (SumVoLTE_InterX2OutSucc/SumVoLTE_InterX2 OutAtt) * 100 %

VoLTE HO X2 Success rate

VoLTE_S1HoSuccessRate = (SumVoLTE_InterS1OutSucc/SumVoLTE_InterS1 OutAtt) * 100 %

VoLTE HO S1 Success rate

LBHO_KPI Definition: These KPIs measure load-balancing handover success rate.

Formula Name

Description

InterEnbHoSuccRatio = (SumInterEnbMlbHoSucc/SumInterEnbMlbHoAtt) * 100 %

Inter-eNB load balancing handover success rate

IntraEnbIntraCarrierGroupHoSuccRatio = (SumIntraEnbIntraCarrierGroupMlbHoSucc/SumIntr aEnbIntraCarrierGroupMlbHoAtt) * 100 %

Intra-eNB load balancing handover success rate to a separate carrier within the same eNodeB of the same frequency due to load balancing

IntraEnbInterCarrierGroupHoSucRatio = (SumIntraEnbInterCarrierGroupMlbHoSucc/SumIntr aEnbInterCarrierGroupMlbHoAtt) * 100 %

Intra-eNB load balancing handover success rate to a separate carrier within the same eNodeB of the different carrier group due to load balancing

SendbackHOSuccRatio = (SumSendbackHOSucc/SumSendbackHOAtt) * 100 %

Handover success ratio by sendback in SeNB

SYSTEM OPERATION How to Activate This feature runs automatically. eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Counters and KPIs For detailed information, refer to system counter description.

REFERENCE [1] LTE eNB System Counter Description_SLR5.0.0. [2] 3GPP TS 32.450: Key performance indicators: Definitions. [3] 3GPP TS 32.425: Performance measurements. [4] 3GPP TS 32.404: Performance measurements: Definitions and templates.


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LTE-OM9101, L1 and L2 Counters INTRODUCTION Layer 1 (L1) and Layer 2 (L2) counters provide data for statistical analysis at PHY/MAC layers. This data is used to monitor E-UTRAN performance. Some of these counters are defined in TS32.425 while others are specific to Samsung. This feature provides a brief introduction to counters. Only the counters which are visible to operators and are collected at PHY/MAC layers are included in this feature. For detailed information about all available counters, refer to Samsung LTE system counter description manual.

BENEFIT The operator can get data to perform statistical analysis related to the following:

Air MAC performance PRB utilization Radio resource utilization Random access performance Hybrid ARQ performance Adaptive modulation and coding performance Carrier aggregation performance eICIC performance E-RAB session time Received signal power statistics Transmitted signal power statistics


LIMITATION None



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FEATURE DESCRIPTION AIR MAC/RLC PERFORMANCE AIR_MAC_BYTES Name

Description

AirMacByteUl

The sum of the size of the MAC PDU successfully received via PUSCH during the statistics period.

AirMacTtiUl

The sum of sections that have the MAC PDU successfully received via PUSCH during the statistics period.

AirMacUlThru


AirMacUlEfctivThru

Average size of the MAC PDU of the section successfully received via PUSCH during the statistics period.

AirMacByteDl

The sum of the size of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

AirMacTtiDl

The sum of sections that have the MAC PDU successfully transmitted via PDSCH during the statistics period.

AirMacDlThru

Average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

AirMacDlEfctivThru

Average size of the MAC PDU of the section successfully transmitted via PDSCH during the statistics period.

AirMacUlThruMin


AirMacUlThruMax


AirMacDlThruMin

Minimum of the average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

AirMacDlThruMax

Maximum of the average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

ULIpThruVol

The cumulated number that indicates the sum of the sizes of MAC SDUs that were successfully received through the PUSCH during the sample intervals of all UEs in the collection interval.

ULIpThruTime

The cumulated number of TTIs during the sample intervals of all UEs in the collection interval.

ULIpThruAvg

The calculated number that indicates the average per second size which is derived from that the MAC SDUs that were successfully received through the PUSCH during the sample intervals of all UEs is divided by TTIs during the sample intervals in the collection interval.

AIR_MAC_BYTES_PLMN Name

Description

PLMNAirMacULByte

The sum of the size of the MAC PDU successfully received via PUSCH during the statistics period.

PLMNAirMacULTti


PLMNAirMacULThruAvg


PLMNAirMacULEfctivThruA

Average size of the MAC PDU of the section successfully received via PUSCH


922

Chapter 10 System Test and Analysis Name vg

Description during the statistics period.

PLMNAirMacDLByte

The sum of the size of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

PLMNAirMacDLTti

The sum of sections that have the MAC PDU successfully transmitted via PDSCH during the statistics period.

PLMNAirMacDLThruAvg

Average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period.

PLMNAirMacDLEfctivThruA vg


PLMNAirMacULThruMin


PLMNAirMacULThruMax


PLMNAirMacDLThruMin

Minimum of the average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

PLMNAirMacDLThruMax

Maximum of the average size per second of the DCCT/DTCH MAC PDU that received HARQ ACK among the MAC PDU transmitted via PDSCH during the statistics period

AIR_MAC_BYTES_PCELL Name

Description

AirMacULByte


AirMacULByteCnt


AirMacULTti

The sum of sections that have the MAC PDU successfully received via PUSCH during the statistics period

AirMacULThruAvg

Average size per second of the MAC PDU successfully received via PUSCH



AirMacDLByte


AirMacDLByteCnt


AirMacDLTti


AirMacDLThruAvg




AirMacULByteCurr


AirMacDLByteCurr


AirMacULThruMin


AirMacULThruMax


AirMacDLThruMin



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Description

AirMacDLThruMax


AIR_MAC_BYTES_SCELL Name

Description

AirMacULByte


AirMacULByteCnt


AirMacULTti


AirMacULThruAvg




AirMacDLByte


AirMacDLByteCnt


AirMacDLTti


AirMacDLThruAvg




AirMacULByteCurr


AirMacDLByteCurr


AirMacULThruMin


AirMacULThruMax


AirMacDLThruMin


AirMacDLThruMax


IP_LATENCY (Collected per cell per QCI) Name

Description

IpLateDL

IP Latency in the downlink collected at bearer level

IpLateDLTot

Time difference between reception time of IP packet and the time when the eNodeB transmits the first block to UE

IpLateDLCnt

Number of samples (defined in 3GPP TS 32.450)

PRB UTILIZATION PRB_QCI eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

PrbDl

The PRB usage used as the downlink DTCH traffic

PrbUl

The PRB usage used as the uplink DTCH traffic

PRB_TOTAL Name

Description

TotPrbDLAvg

The resource used for the PDSCH/PDCCH transmission among the total downlink resource

TotGbrPrbDLAvg

Ratio of the resource used to transmit the GBR traffic against the total downlink resources.

TotNGbrPrbDLAvg

Ratio of the resource used to transmit the non-GBR traffic against the total downlink resources.

TotPrbULAvg

The resource used for the PUSCH transmission among the total uplink resource

TotGbrPrbULAvg

Ratio of the resource used to transmit the GBR traffic against the total uplink resources.

TotNGbrPrbULAvg

Ratio of the resource used to transmit the non-GBR traffic against the total uplink resources.

TotPucchPrbULAvg

The resource used for the PUCCH transmission among the total uplink resource

TotPucchPuschPrbULAvg

The resource used for the PUCCH/PUSCH transmission among the total uplink resource

TotNgbrSCellPrbDLAvg

Ratio of the resource used to transmit the non-GBR traffic of SCell against the total downlink resources.

TotPrbDLMin

The minimum value of TotPrbDLAvg

TotPrbDLMax

The maximum value of TotPrbDLAvg

TotPrbULMin

The minimum value of TotPrbULAvg

TotPrbULMax

The maximum value of TotPrbULAvg

PRB_TOTAL_PLMN Name

Description

TotPrbDl_PLMN

Ratio of resource used for PDSCH/PDCCH transmission against the total PLMN downlink resource available.

TotPrbDlMin_PLMN

Minimum value of PLMNTotPrbDLAvg

TotPrbDlMax_PLMN

Maximum value of PLMNTotPrbDLAvg

TotPrbUl_PLMN

Ratio of resource used for PUSCH reception against the total PLMN uplink resource available.

TotPrbUlMin_PLMN

Minimum value of PLMNTotPrbULAvg

TotPrbUlMax_PLMN

Maximum value of PLMNTotPrbULAvg

PRB_SMART Name

Description

TotPrbCsRatio

The ratio of PRB to which coordinated scheduling is applied

TotPrbJtRatio

The ratio of PRB to which joint transmission is applied


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Description

TotPrbDLAllocRatio

The total ratio of allocated PRB

TotPrbCs

Total count of PRB to which coordinated scheduling is applied

TotPrbJt

Total count of PRB to which joint transmission is applied

TotPrbDLAvail

Total count of available PRB

TotPrbDLAlloc

Total count of allocated PRB

TotPrbNormRatio

The ratio of PRB to which normal (excluding CS/JT) scheduling is applied based on the total available PRB

TotPrbCsAllocRatio

The ratio of PRB to which coordinated scheduling is applied based on the allocated PRB

TotPrbJtAllocRatio

The ratio of PRB to which Joint transmission is applied based on the allocated PRB

TotPrbNormAllocRatio

The ratio of PRB to which normal (excluding CS/JT) scheduling is applied based on the allocated PRB

TotPrbNorm

Total count of PRB to which normal (excluding CS/JT) scheduling is applied

PRB_FULL_UTILIZATION Name

Description

DLPrbFullUtilRatio

The percentage of time during which all avaialble PRBs for the downlink have been assigned

ULPrbFullUtilRatio

The percentage of time during which all avaialble PRBs for the uplink have been assigned

RADIO RESOURCE UTILIZATION RRU_MEAS Name

Description

RruCceUsageDistDL1

Aggregation Level 1 of PDCCH DL grant

RruCceUsageDistDL2


RruCceUsageDistDL4


RruCceUsageDistDL8


RruCceUsageDistUL1

Aggregation Level 1 of PDCCH UL grant

RruCceUsageDistUL2


RruCceUsageDistUL4


RruCceUsageDistUL8


RruCceAllocationFailDLAvg

Average CCE allocation failure rate of PDCCH DL grant

RruCceAllocationFailULAvg

Average CCE allocation failure rate of PDCCH UL grant

RruPrbDLPcchAvg

Average usage rate of PCCH PRB

RruPrbULSrbAvg

Average PRB usage rate of Uplink SRB

RruPrbDLSrbAvg

Average PRB usage rate of Downlink SRB

RRU_MEAS_NEW Name

Description


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Description

RruCceUsageDistDL1

Aggregation level1 of PDCCH DL grant

RruCceUsageDistDL2


RruCceUsageDistDL4


RruCceUsageDistDL8


RruCceUsageDistUL1

Aggregation level1 of PDCCH UL grant

RruCceUsageDistUL2


RruCceUsageDistUL4


RruCceUsageDistUL8


RruCceAllocationFailDLAvg

The CCE allocation fail ratio of PDCCH DL grant

RruCceAllocationFailULAvg

The CCE allocation fail ratio of PDCCH UL grant

RruPrbDLPcchAvg

PCCH PRB Usage

RruPrbDLSrbAvg

Downlink SRB (CCCH/DCCH) PRB Usage

RruPrbULSrbAvg

Uplink SRB (CCCH/DCCH) PRB Usage

PDCCH Name

Description

Cfi1

The number of used CFI1

Cfi2


Cfi3


PDCCHCceUsedAgg1

The number of used aggregation level 1 for allocating PDCCH CCE

PDCCHCceUsedAgg2


PDCCHCceUsedAgg4


PDCCHCceUsedAgg8


PDCCHCcePerUser

The average number of allocated CCE per UE

ACTIVE_UE Name

Description

UEActiveDl

The number of UEs satisfying one or more of the following conditions in a continuous 20 ms interval (sampling occasion) is summed every 80 ms for each QCI. If there is a DRB which received a buffer occupancy Request from the RLC If there is a DRB which received an HARQ retransmission Request When a collection interval ends, the average is calculated by dividing the summed number of UEs by the number of sampling occasions that occurred.

UEActiveDlTot

Sum of UEActiveDLAvg collected

UEActiveUl

The number of UEs satisfying one or more of the following conditions in a continuous 20 ms interval is summed every 80 ms for each QCI. If there is a DRB where the uplink data requested to be allocated using the Buffer Status Report message is waiting If there is a DRB which received an HARQ retransmission request When a collection interval ends, the average is calculated by dividing the summed number of UEs by the number of sampling occasions that occurred.

UEActiveUlTot

Sum of UEActiveULAvg collected


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Description

SumActiveUEDL

This counter is the cumulated number per every TTI of DL DRB for each QCI which receives a buffer occupancy request from the RLC or which has received a HARQ retransmission request during the sampling period.

SumActiveUEUL

This counter is the cumulated number per every TTI of UL DRB for each QCI where the uplink data requested to be allocated using the Buffer Status Report message is waiting or which received an HARQ retransmission request.

POWER_HEADROOM Name

Description

PhrIndex0

The cumulated count that PhrIndex0 is received

PhrIndex1


⁞

⁞

PhrIndex62


PhrIndex63


RANDOM ACCESS PERFORMANCE RA Name

Description

HighSpeedMonitoring

The number of UEs which are monitored for moving speed

NoofHighSpeed

The number of high speed UEs which are monitored

DedicatedPreambles

The number of detected dedicated preambles.

DedicatedPreambleAssignF ail

The number of failures to get dedicated preamble allocation after requesting the dedicated preamble from the RRC to the MAC

Randomlyselectedpreamble sLow

The number of the preambles belonging to Group A among the detected contention based preambles

Randomlyselectedpreamble sHigh

The number of the preambles belonging to Group B among the detected contention based preambles

RACHUsageAvg

Average number of detected preambles

HandoverDedicatedPreambl es

The cumulated number of dedicated preambles due to HO order among the periodically collected RACH preambles.

RandomAccessResponses

The cumulated number of RandomAccessResponse (RAR) messages transmitted. For this counter, the statistics are collected periodically.

UE_LIMIT_TA_INITIAL_ATTACH Name

Description

RARFailByTaLimitation

The number of not-transmitted RAR’s due to TA Threshold in the UE Initial Attach. If taBasedUeLimitFlag is set as 1 and if the TA value assumed by BTS after receiving preamble is larger than taThresholdForAttach, RAR is not transmitted for the preamble.


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Timing alignment statistics families (TA, TA_RRE, TA_NORMAL_RELEASE, TA_ABNORMAL_RELEASE, TA_HO) Timing Advance (TA) is a MAC Control Element (CE) that is used to control uplink signal transmission timing. Timing advance is a negative offset, at the UE, between the start of a received downlink subframe and a transmitted uplink subframe. Timing Advance offset compensates the propagation delay between eNB and UE. Below figure illustrates how propagation delay is compensated with TA command. UE adjusts the uplink transmission by „2 * δ‟ so that eNB receives the uplink data on the exact uplink subframe boundary. eNB can either send an absolute timing advance value or a relative timing adjustment value. Absolute TA value is 11-bit in size and is sent only during random access procedure (in random access response message). Relative timing adjustment is 6-bit in size and can be sent any time when UE is connected, using Timing Advance MAC control element. In case of random access response, the 11-bit timing advance command, NTA * 16. In other cases, a 6-bit timing advance command indicates adjustment of the current NTAvalue, NTA,old to the new NTA value, NTA,new where NTA, new = NTA,old + (A -31)16. Here, adjustment of NTA value by a positive or a negative amount indicates advancing or delaying the uplink transmission.

Categorizing the TA distribution according to specific events provides information about the distribution of distance from cell site where the events are occurring. This statistical information can be used for network optimization and planning. Samsung eNB provides a TA Distribution OM Family with 5 TA Distribution OM Groups:

Call Attempt TA Re-establishment TA Normal Call Release TA Abnormal Call Release TA Handover TA eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Though the OM group name indicates timing advance (TA), the distribution counters are provided in terms of distance from cell site in meters. Each of these OM groups provides PDF of UE distance with smaller granularity near cell center and with progressively reduced granularity towards cell edge. Call Attempt TA, Re-establishment TA and Handover TA are calculated based on the absolute timing advance value (11-bit) sent to UE as part of random access procedure. This TA value is converted to distance in meters to provide the respective TA OM groups. Abnormal Call Release TA and Normal Call Release TA OM groups are calculated based on the final TA value. eNB sends multiple relative timing adjustment values (6-bit) to UE until the call is released normally or abnormally. eNB calculates the final TA value of a UE by accumulating these relative TA values onto the last absolute TA value sent to UE. This final TA value is then converted to distance in meters to provide the respective TA OM groups. Call Attempt TA (TA family) Call Attempt TA is pegged when eNB receives Msg3 successfully as part of RRC connection establishment procedure. This TA OM Group pegs the timing advance sent to UE in RAR MAC PDU in those cases where MSG3 is RRC Connection Request message. The TA value sent to UE in this case is 11-bit absolute timing advance value. Call attempt TA OM group is pegged irrespective of accessibility success or failure after MSg3 reception at eNB. Call Attempt TA OM group is not pegged in the following cases that involve RACH procedure: Initial RACH procedure fails (for example, MSG3 time-out). UE performs RRC Connection Re-establishment to serving cell when a call is ongoing, the Call Attempt TA OM does not get affected as it is already pegged when MSG3 is received. UE performs RACH procedure after maximum re-transmission of Scheduling Request (dsr-TransMax). In this case, Call Attempt TA is not affected as the MSG3 received is not RRC Connection Request message (MSG3 in this scenario will be CRNTI control element along with/without BSR). UE performs RACH procedure due to the reception of PDCCH order from eNB. In this case also, call attempt TA is not affected, as the MSG3 received is not RRC Connection Request message (MSG3 in this case will be CRNTI MAC Control element). Name

Description

TimeAdvanceSection0

Distance (meter): 0~200, 16TS: from 0 to 2.

TimeAdvanceSection1


⁞

⁞

TimeAdvanceSection30

Distance (meter): 60001~, 16TS: from 768 onwards.

Re-establishment TA (TA_RRE family) Connection Re-establishment TA is pegged when eNB receives Msg3 successfully as part of RRC connection Re-establishment procedure. This TA OM group pegs the timing advance sent to UE in RAR MAC PDU in those cases where MSG3 is RRC Connection Re-establishment Request message. The TA value sent to UE in this case is 11-bit absolute timing advance value. Connection Re-establishment TA OM group is pegged when eNB receives RRC Connection Re-establishment eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Request message, irrespective of whether the re-establishment attempt was rejected (RRC Connection Re-establishment Reject) or accepted (RRC Connection Re-establishment). During handover procedure, target eNB may receive RRC Connection Re-establishment Request as MSG3 (UE performs re-establishment procedure in case of HO failure). In this case, Connection Re-establishment TA is pegged at the target eNB. Name

Description

RRE_TimeAdvanceSection0




⁞

⁞



Normal Call Release TA (TA_NORMAL_RELEASE family) Normal Call Release TA is pegged when a call is released normally, i.e., with any cause that is not related to accessibility failures and call drops. The cases include normal releases such as user inactivity-triggered release, MME-triggered releases, call release due to CSFB, call release due to inter-RAT re-direction, call releate in source eNB after successful handover etc. Normal call release TA is pegged after accumulating all relative TA values sent to UE after the last absolute TA value transmission. This accumulated TA value is converted to distance from cell site and is used to update the OM counter. This calculated distance will indicate the distance at which the call is released. Name

Description

NormalRelease_TimeAdvanceSection0




⁞

⁞



Abnormal Call Release TA (TA_ABNORMAL_RELEASE family) Abnormal Call Release TA is pegged when call is released with one of the cause that is not pegged under Normal Call Release TA, ie. all abnormal call release cases. The cases include call drops, accessibility failures, and other abnormal cases. This OM group provides information about the cell site distance where abnormal call releases are happening. Higher abnormal call releases at a specific cell site distance might call for network optimizations, drive tests etc. Abnormal Call Release TA is pegged after accumulating all relative TA values sent to UE after the last absolute TA value transmission. This accumulated TA value is converted to distance from cell site and is used to update the OM counter. Below is the list of cause values for which Abnormal Call Release TA is pegged:

Call Drop cases: CallDrop_„*‟ counters in CALL_DROP (24) counter family where „*‟ denotes a drop cause.

Failure Causes in RRC Connection Establishment OM group: ConnEstabFail_„*‟ counters in RRC_ESTAB counter family where „*‟ denotes a failure cause.

Failure Causes in E-RAB Setup OM group: ErabInitFailNbr_„*‟ counters in ERAB_ESTAB counter family where „*‟ denotes a failure cause.


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Failure Causes in UE-associated logical S1 Connection Establishment OM group: S1ConnEstabFail_„*‟ counters in S1SIG counter family where „*‟ denotes a failure cause. For more information about CALL_DROP, RRC_ESTAB, ERAB_ESTAB, and S1SIG counter families, please refer to LTE system counter description manual. Name

Description

AbnormalRelease_TimeAdvanceSection0




⁞

⁞



Handover TA (TA_HO family) Handover TA is pegged when MSG3 is received successfully as part of handover procedure in target cell. In handover scenarios, the MSG3 received at target eNB can either be RRC Connection Reconfiguration Complete message or RRC Connection Re-establishment message. In both of these cases, handover is considered as success if UE gets connected to the target cell successfully. But Handover TA is pegged only when eNB receives RRC Connection Reconfiguration Complete message as the MSG3. In case, RRC Connection Reestablishment Request is received as MSG3 during handover, the TA value is pegged as Connection Re-establishment TA and not Handover TA. Random access procedure in case of handover can either be contention based or contention free and in both cases, the TA will be pegged in Handover TA OM group, if the MSG3 received is RRC Connection Reconfiguration Complete message. Name

Description

HOTimeAdvanceSection0

The cumulated count of the case that TA of RACH success UE in handover is between 0 and 2.


The cumulated count of the case that TA of RACH success UE in handover is between 3 and 5.

⁞

⁞


The cumulated count of the case that TA of RACH success UE in handover is greater than 768.

Carrier Aggregation In case of carrier aggregation, as uplink CA is not supported, timing advance value for the PCell is pegged for all of the TA OM groups discussed above.

HYBRID ARQ PERFORMANCE TRANSMISSION Name

Description


PDSCH BLER for the initial HARQ transmission.


PDSCH BLER for the first HARQ retransmission.


PDSCH BLER for the second HARQ retransmission.


PDSCH BLER for the third HARQ retransmission.


Number of initial PDSCH HARQ transmissions


932


Description


Number of first PDSCH HARQ retransmissions


Number of second PDSCH HARQ retransmissions


Number of third PDSCH HARQ retransmissions

DlTransmission_Nacked_Retrans3

Number of third PDSCH HARQ retransmission failures

UlResidualBLER_Retrans0

PUSCH BLER for the initial HARQ retransmission.


PUSCH BLER for the first HARQ retransmission.

⁞

⁞


PUSCH BLER for the twenty sixth HARQ retransmission.


PUSCH BLER for the twenty seventh HARQ retransmission.

UlTransmission_Retrans0

Number of initial PUSCH HARQ transmissions


Number of first PUSCH HARQ retransmissions


Number of second PUSCH HARQ retransmissions

⁞

⁞


Number of twenty sixth PUSCH HARQ retransmissions


Number of twenty seventh PUSCH HARQ retransmissions

UlTransmission_Nacked_Retrans27

Number of twenty seventh PUSCH HARQ retransmissions

DlResidualBLER_RetransAvg

Average of distribution for DLResidualBLERRetrans.

UlResidualBLER_RetransAvg

Average of distribution for ULResidualBLERRetrans.

DlResidualBLER_RetransNak

PDSCH BLER for HARQ NACK.

UlResidualBLER_RetransNak

PUSCH BLER for HARQ NACK.

DlResidualBLER_RetransMin

Minimum value of DLResidualBlerRetrans

DlResidualBLER_RetransMax

Maximum value of DLResidualBlerRetrans

UlResidualBLER_RetransMin

Minimum value of ULResidualBlerRetrans

UlResidualBLER_RetransMax

Maximum value of ULResidualBlerRetrans

MIMO Name

Description

PdschBLERperLayer

PDSCH BLER for each layer

PuschBLERperLayer

PUSCH BLER for each layer

MIMO_NEW Name

Description

PdschTransmissionPerLayer

Transmission count per layer for PDSCH

PdschErrorPerLayer

PDSCH error count for each layer

PuschTransmissionPerLayer

Transmission count per layer for PUSCH

PuschErrorPerLayer

PUSCH error count for each layer

MCS Name

Description

PdschBLERperMCS0

PDSCH BLER transmitted to MCS 0


933


Description

PdschBLERperMCS1


⁞

⁞

PdschBLERperMCS30


PdschBLERperMCS31


PuschBLERperMCS0

PUSCH BLER received from MCS 0

PuschBLERperMCS1


⁞

⁞

PuschBLERperMCS30


PuschBLERperMCS31


UlReceivedMCS0

The number of times PUSCH of MCS 0 is received

UlReceivedMCS1


⁞

⁞

UlReceivedMCS30


UlReceivedMCS31


DlSchedulerMCS0

The number of PRBs assigned to PDSCH MCS 0

DlSchedulerMCS1


⁞

⁞

DlSchedulerMCS30


DlSchedulerMCS31


UlSchedulerMCS0

The number of PRBs assigned to PUSCH MCS 0

UlSchedulerMCS1


⁞

⁞

UlSchedulerMCS30


UlSchedulerMCS31


DL_ACK_NACK_DTX_RATIO Name

Description

DlreceivedAckNackDtxRatio

ACK, NACK, DTX ratio

ADAPTIVE MODULATION AND CODING PERFORMANCE DL_MCS Name

Description

DlTransmittedMCS0

The number of times that MCS 0 PDSCH is transmitted per layer/ codeword

DlTransmittedMCS1

The number of times that MCS 1 PDSCH is transmitted per layer/ codeword

⁞

⁞

DlTransmittedMCS30

The number of times that MCS 30 PDSCH is transmitted per layer/codeword

DlTransmittedMCS31

The number of times that MCS 31 PDSCH is transmitted per layer/codeword


934


DL_LAYER Name

Description

DlTransmittedLayer

Transmission counts per layer for PDSCH

DL_CQI Name

Description

DLReceivedCQI0

The number of times that CQI 0 is received per layer/codeword

DLReceivedCQI1


DLReceivedCQI2


DLReceivedCQI3


DLReceivedCQI4


DLReceivedCQI5


DLReceivedCQI6


DLReceivedCQI7


DLReceivedCQI8


DLReceivedCQI9


DLReceivedCQI10


DLReceivedCQI11


DLReceivedCQI12


DLReceivedCQI13


DLReceivedCQI14


DLReceivedCQI15


DLReceivedCQIMin

Minimum value of DLReceivedCQI

DLReceivedCQIMax

Maximum value of DLReceivedCQI

DLReceivedCQIAvg

Average value of DLReceivedCQI

DL_CQI_NEW Name

Description

DlReceivedCQIAvg

Average value of DL received CQI

DlReceivedCQI0


DlReceivedCQI1


⁞

⁞

DlReceivedCQI14


DlReceivedCQI15


DlReceivedCQIMin

Minimum value of DLReceivedCQI

DlReceivedCQIMax

Maximum value of DLReceivedCQI

CQIErase

Number of times layer/codeword CQI is erased

DL_CQI_NEW_PCELL Name

Description

DLReceivedCQI0

Number of receiving CQI 0 for a wideband CQI per


935


Description layer/codeword transmitted from CA UE whose the cell is PCell

DLReceivedCQI1


⁞

⁞

DLReceivedCQI14


DLReceivedCQI15


DLReceivedCQIMin

The minimum value of DlReceivedCQI received from CA UE whose cell is PCell

DLReceivedCQIMax

The maximum value of DlReceivedCQI received from CA UE whose cell is PCell

DLReceivedCQIAvg

The average value of DlReceivedCQI received from CA UE whose cell is PCell

CQIErase

Number of times that CQI erase per layer/codeword is received from CA UE whose cell is PCell

DL_CQI_NEW_SCELL Name

Description

DLReceivedCQI0


DLReceivedCQI1


⁞

⁞

DLReceivedCQI14


DLReceivedCQI15


DLReceivedCQIMin

The minimum value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

DLReceivedCQIMax

The maximum value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

DLReceivedCQIAvg

The average value of DlReceivedCQI transmitted from CA UE whose the cell is SCell

CQIErase

Number of times that CQI erase per layer/codeword is received from CA UE whose cell is SCell

DL_SUBBAND_CQI Name

Description

DLReceivedSubband0CQI0

The number of times that CQI 0 of subband0 is received



⁞

⁞





DLReceivedSubband0CQIMin

The minimum value of DLReceivedCQI in the subband0


936


Description

DLReceivedSubband0CQIMax

The maximum value of DLReceivedCQI in the subband0

DLReceivedSubband0CQIAvg

The average value of DLReceivedCQI in the subband0

Subband0CQIErase

The number of times that CQI erase of subband0 is received





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Subband1CQIErase


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Subband11CQIErase






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Subband12CQIErase


DL_PMI Name

Description

DlReceivedPMI0

The number of times that PMI 0 is received

DlReceivedPMI1


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DlReceivedPMI14


DlReceivedPMI15


DL_RI eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

DlReceivedRIAvg

Average value of DL received RI

DlReceivedRI0

Reserved

DlReceivedRI1

The number of times that RI 1 is received

DlReceivedRI2


DlReceivedRI3


DlReceivedRI4


CARRIER AGGREGATION PERFORMANCE CA_ACT_DEACT Name

Description

SCellActivation

Count of activations (SCell)

SCellDeactivation_TO

Count of SCell deactivation occurrences by reason: When deactivation timer expires (SCell)

SCellDeactivation_Mismatch

Count of SCell deactivation occurrence by reason: When CA status of eNB and that of the UE are different (SCell)

CRNTIcollision

The number of Scell Activation fail due to C-RNTI collision (The C-RNTI of UE, who requests Scell activation to SCell, is already used in SCell)

SCellActUEAvg

The average number of Scell activated Ues

CA_ACT_INFO Name

Description

SCellActUEAvg

The average number of Scell activated Ues

SCellActivatedTime

The total time of Scell activated time

EICIC PERFORMANCE EICIC_ABS Name

Description

AvgABSNum

Average ABS number

ABSBin0

The ratio of not using ABS pattern

ABSBin5

The using ratio of ABS pattern used 5/40 as ABS ratio

ABSBin6


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ABSBin22


ABSBin23


E-RAB SESSION TIME ERAB_SESSION_UE Name

Description


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Description

SessionTimeUEAvg

Average in-session time per UE

SessionTimeUETot

Sum of SessionTimeUEAvg collected

ERAB_SESSION_QCI Name

Description

SessionTimeQciAvg

Average in-session time per QCI

SessionTimeQciTot

Sum of SessionTime SessionTimeQciAvg collected

RECEIVED SIGNAL POWER STATISTICS POWER Name

Description

InterferencePower

Average interference over thermal noise for each PRB

ThermalNoisePower

Average Thermal Noise

RssiOverPath

Average RSSI for each antenna

RssiPath0

Average RSSI of Antenna #0

RssiPath1

Collected RssiPath0Avg count

RNTP Name

Description

RntpOwnCell_PRB0

RNTP of downlink PRB #0.

RntpOwnCell_PRB1


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RntpOwnCell_PRB98


RntpOwnCell_PRB99


RU_RSSI Name

Description

RuRssiAvg

The average values of RSSI

RuRssiMax

The maximum values of RSSI

RuRssiCurr

The most recently collected RSSI values

RuRssiTot

The total sum of the RSSI values

RuRssiCnt

Number of times that the RSSI values were collected

IIU_RSSI Name

Description

IiuRssiAvg

The average values of RSSI

IiuRssiMax

The maximum values of RSSI


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Description

IiuRssiCurr

The most recently collected RSSI values

IiuRssiTot

The total sum of the RSSI values

IiuRssiCnt

Number of times that the RSSI values were collected

RRH_RSSI Name

Description

RrhRssiAvg

The average values of RSSI for each RRH path

RrhRssiMax

The maximum values of RSSI for each RRH path

RrhRssiCurr

The most recently collected RSSI values for each RRH path

RrhRssiTot

The total sum of the RSSI linear values for each RRH path

RrhRssiCnt

Number of times that the RSSI values were collected for each RRH path

RrhRssidBmAvg

The average values of RSSI dBm for each RRH path

RrhRssidBmTot

The total sum of the RSSI dBm values for each RRH path

RrhRssidBmCnt

Number of times that the RSSI dBm values were collected for each RRH path

RSSI_PATH Name

Description

RssiPathAvg

The average value of RSSI for each path

RssiPathMax

The maximum value of RSSI for each path

RssiPathCurr

The most recently collected RSSI values for each path

RssiPathTot

Sum of RSSI values for each path

RssiPathCnt

RSSI values collection count for each path

IOT Name

Description

IotAvg

IoT Average

IotMin

IoT Min

IotMax

IoT Max

IOT_9LEVEL - Collected per cell per level (9 possible levels) Name

Description

PRB0

IoT Level Count for PRB0

PRB1


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PRB98


PRB99


UL_SINR_DISTRIBUTION eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

940


Description

SinrDistULWbPreComp_Bin0

Uplink SINR Bin0 (-10~-8 dB) count before Outer-loop compensation


Uplink SINR Bin1 (-8~-6 dB) count before Outer-loop compensation

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Uplink SINR Bin18 (26~28) count before Outer-loop compensation


Uplink SINR Bin19 (28~30) count before Outer-loop compensation

SinrDistULWbPostComp_Bin0

Uplink SINR Bin0 (-10~-8 dB) count after Outer-loop compensation


Uplink SINR Bin1 (-8~-6 dB) count after Outer-loop compensation

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Uplink SINR Bin18 (26~28 dB) count after Outer-loop compensation


Uplink SINR Bin19 (28~30 dB) count after Outer-loop compensation

PUCCH_SINR_DISTRIBUTION Name

Description

PUCCHSinrDistBin0

The cumulated number of PUCCH SINR Bin0 (-10~-8 dB).

PUCCHSinrDistBin1

The cumulated number of PUCCH SINR Bin1 (-8~-6 dB).

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PUCCHSinrDistBin19

The cumulated number of PUCCH SINR Bin19 (28~30 dB).

PUSCH_TX_POWER Name

Description

PhrRxCount

This counter is cumulated by 1 when PHR is received.

TxPowerSum

This counter is cumulated by the PUSCH Tx Power when PHR is received.

PowerLimitCount

This counter is cumulated by 1 if (PHR index-23) is less than 0 when PHR is received.

AveragePuschTxPower

Average PUSCH transmission power

PowerShortageRatio

Percentage of received PHRs with PHR index-23 < 0.

PUCCH_INTERFERENCE_POWER Name

Description

PucchInterferencePowerAvg

The average value of interference power per PRB in the PUCCH region.

TRANSMITTED SIGNAL POWER STATISTICS RRH_TX_POWER eNB (LTE) Feature Description for PKG 6.0.0 v1.0 © Samsung Proprietary and Confidential

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Description

RrhTxPowerAvg

The average value of RRH TX Power

RrhTxPowerMax

The Maximum value of RRH TX Power

RrhTxPowerCurr

The most recently collected RRH TX Power

RrhTxPowerTot

The total sum of the RRH TX Power values

RrhTxPowerCnt

Number of times that the RSSI values were collected for each RRH TX Power

UE_TX_POWER Name

Description

PuschRbCountAvg

Number of average uplink RBs except PUCCH RB

PuschRbCountTot

Number of accumulated uplink RBs except PUCCH RB

PuschRbCountCnt

Count of PuschRbCountAvg called

UETxPowerPrbAvg

Average UE TX Power on RB

UETxPowerPrbTot

Accumulated UE TX Power on RB

UETxPowerPrbCnt

Count of UETxPowerPrbAvg called

AllocCount

Number of RBs allocated for PUSCH

RRH_UE Name

Description

RrhUE

The number of UEs per RRH Count when UE operates PRACH process. Count when RRH recieves MSG3 In the same RRH, when UE operates PRACH process, duplicate count may occur. During measurement period, when UE does not operate PRACH process, the corresponding UE is not counted for this counter. (Specificailly, when a UE moves between main cell and copy cell and, it does not operate PRACH process, the corresponding UE is not counted for this counter)

RF Name

Description

RuGain

RU Gain

RuGainCnt

a number of collection of RuGain

TxRfPower

Tx RF Power

TxRfPowerCnt

a number of collection of TxRfPower

OverpowerAlarmThr

Overpower alarm threshold

OverpowerAlarmThrCnt

a number of collection of OverpowerAlarmThr

LowpowerAlarmThr

Lowpower alarm threshold

LowpowerAlarmThrCnt

a number of collection of LowpowerAlarmThr

RfTemp

RF Temperature

RfTempCnt

a number of collection of RfTemp


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TX_DIGITAL_IQ Name

Description

TxDigitalIq

Tx Digital I/Q

TxDigitalIqCnt

a number of collection of TxDigitalIq

SMART_SON_TX_POWER Name

Description

SmartSon_TxPowerAvg

The Average value of Tx Power

SmartSon_TxPowerMax

The Maximum value of Tx Power

SmartSon_TxPowerMin

The Minimum value of Tx Power

SmartSon_TxPowerTot

The total sum of Tx Power

SmartSon_TxPowerCnt

Number of times that the TxPower values were collected

SYSTEM OPERATION How to Activate This feature is basically enabled. The statistical data are collected during the eNodeB operaion and transmitted to the LSM.

Key Parameters There are no related parameters

Counters and KPIs For detailed information about all available counters, refer to Samsung LTE system counter description manual.

REFERENCE [1] LTE eNB System Counter Description_SLR4.5.0. [2] 3GPP TS 32.450: Key performance indicators: Definitions. [3] 3GPP TS 32.425: Performance measurements. [4] 3GPP TS 32.404: Performance measurements: Definitions and templates.


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eNB (LTE) Feature Description for PKG 6.0.0 Document Version 1.0 © 2016 Samsung Electronics Co., Ltd. All rights reserved.

ENB (LTE) Feature Description for PKG 6.0.0_v1.0

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