Cloud BB Overview(SRAN10.1_02)

SingleRAN

Cloud BB Overview Feature Parameter Description Issue

02

Date

2015-08-31

HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2015. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty of any kind, express or implied.

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Website:

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Email:

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Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

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SingleRAN Cloud BB Overview Feature Parameter Description

Contents

Contents 1 About This Document.................................................................................................................. 1 1.1 Scope.............................................................................................................................................................................. 1 1.2 Intended Audience.......................................................................................................................................................... 1 1.3 Change History............................................................................................................................................................... 1 1.4 Differences Between eNodeB Types.............................................................................................................................. 2

2 Overview......................................................................................................................................... 3 3 Cloud BB Interconnection............................................................................................................6 3.1 USU3900-based Multi-BBU Interconnection................................................................................................................ 7 3.2 USU3910-based Multi-BBU Interconnection................................................................................................................ 7 3.3 Coordination over Relaxed Backhaul.............................................................................................................................9

4 Service Features Supported by Cloud BB...............................................................................10 4.1 LTE FDD Features........................................................................................................................................................10 4.1.1 LOFD-070223 UL CoMP based on Coordinated BBU.............................................................................................10 4.1.2 LAOFD-070202 Carrier Aggregation for 2CC based on Coordinated BBU............................................................ 11 4.1.3 LOFD-070208 Coordinated Scheduling based Power Control (Cloud BB)..............................................................11 4.1.4 LAOFD-080201 Inter-eNodeB CA based on Relaxed backhaul.............................................................................. 12 4.1.5 LOFD-081219 UL CoMP Based on Relaxed Backhaul............................................................................................13 4.1.6 LOFD-081208 Inter-eNodeB SFN Based on Coordinated BBU.............................................................................. 13 4.1.7 LOFD-081209 Inter-eNodeB Adaptive SFN/SDMA Based on Coordinated BBU.................................................. 14 4.1.8 LOFD-081220 Inter-BBU Clock Sharing................................................................................................................. 15 4.2 LTE TDD Features........................................................................................................................................................15 4.2.1 TDLOFD-001080 Inter-BBU SFN............................................................................................................................15 4.2.2 TDLOFD-001082 Inter-BBU Adaptive SFN/SDMA............................................................................................... 15 4.2.3 TDLOFD-080203 Coordinated Scheduling based Power Control (Cloud BB)........................................................ 16 4.2.4 TDLOFD-081207 UL CoMP based on Coordinated BBU....................................................................................... 17 4.2.5 TDLAOFD-081411 Inter-eNodeB DL CoMP based on Relaxed backhaul.............................................................. 17 4.2.6 TDLOFD-081213 Inter-BBU Clock Sharing............................................................................................................ 17

5 Parameters..................................................................................................................................... 19 6 Counters........................................................................................................................................ 20 7 Glossary......................................................................................................................................... 21 Issue 02 (2015-08-31)


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Contents

8 Reference Documents................................................................................................................. 22

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1 About This Document

1

About This Document

1.1 Scope This document describes Cloud BB networking, including Cloud BB networking modes and service features supported by Cloud BB. Cloud BB networking involves the following network elements (NEs): l

eNodeB: 3900 series eNodeBs

l

Universal switching unit (USU): USU3910 and USU3900

l

Operations support system (OSS): U2000

1.2 Intended Audience This document is intended for personnel who: l

Need to understand the features described herein

l

Work with Huawei products

1.3 Change History This section provides information about the changes in different document versions. There are two types of changes: l

Feature change Changes in features and parameters of a specified version as well as the affected entities

l

Editorial change Changes in wording or addition of information and any related parameters affected by editorial changes. Editorial change does not specify the affected entities.

SRAN10.1 02 (2015-08-31) This issue includes the following changes. Issue 02 (2015-08-31)


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1 About This Document

Change Type

Change Description

Parameter Change

Affected Entity

Feature change

Added new service features supported by Cloud BB. For details, see 4 Service Features Supported by Cloud BB.

None

Macro and LampSite eNodeBs

Editorial change

Revised descriptions in this document.

None

Macro and LampSite eNodeBs

SRAN10.1 01 (2015-03-23) This is the first commercial release for SRAN10.1. This issue does not include any changes.

SRAN10.1 Draft A (2015-01-15) This document is created for SRAN10.1.

1.4 Differences Between eNodeB Types The features described in this document apply only to macro eNodeBs.

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2 Overview

2

Overview

Cloud BB enables cell coordination between different eNodeBs, and therefore expands the cell coordination scope from intra-eNodeB coordination to inter-eNodeB coordination. The purpose of Cloud BB is to improve network performance and user experience. There are three Cloud BB networking modes: l

Centralized Cloud BB (Ideal Backhaul) (centralized Cloud BB for short)

l

Distributed Cloud BB (Ideal Backhaul) (distributed Cloud BB for short) NOTE

Currently, LTE TDD does not support distributed Cloud BB.

l

Coordination over relaxed backhaul

For details, see Table 2-1.

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2 Overview

Table 2-1 Mapping for Cloud BB networking Cloud BB Interconnection Mode

Cloud BB Networking Mode

Service Feature

USU3900-based multi-BBU interconnection

Centralized mode

l LTE TDD – TDLOFD-001080 Inter-BBU SFN – TDLOFD-001082 Inter-BBU Adaptive SFN/SDMA – TDLOFD-080203 Coordinated Scheduling based Power Control (Cloud BB) – TDLOFD-081207 UL CoMP based on Coordinated BBU l LTE FDD – LOFD-070223 UL CoMP based on Coordinated BBU – LAOFD-070202 Carrier Aggregation for 2CC based on Coordinated BBU – LOFD-070208 Coordinated Scheduling based Power Control (Cloud BB)


l Centralized mode l Distributed mode

l LTE FDD: – LOFD-070223 UL CoMP based on Coordinated BBU – LAOFD-070202 Carrier Aggregation for 2CC based on Coordinated BBU – LOFD-070208 Coordinated Scheduling based Power Control (Cloud BB) – LOFD-081208 Inter-eNodeB SFN Based on Coordinated BBU – LOFD-081209 Inter-eNodeB Adaptive SFN/SDMA Based on Coordinated BBU l LTE TDD: – TDLOFD-001080 Inter-BBU SFN – TDLOFD-001082 Inter-BBU Adaptive SFN/SDMA – TDLOFD-081207 UL CoMP based on Coordinated BBU – TDLOFD-080203 Coordinated Scheduling based Power Control (Cloud BB)

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2 Overview

Cloud BB Interconnection Mode

Cloud BB Networking Mode

Service Feature



l LAOFD-080201 Inter-eNodeB CA based on Relaxed backhaul l LOFD-081219 UL CoMP Based on Relaxed Backhaul

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3

3 Cloud BB Interconnection

Cloud BB Interconnection

Cloud BB interconnection modes: l


l


l


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3.1 USU3900-based Multi-BBU Interconnection In centralized Cloud BB networking mode, the BBUs and USU are directly connected and the cable length is less than 100 m, and the USUs are also directly connected and the cable length is less than 90 m. Figure 3-1 illustrates the centralized Cloud BB networking mode. The ODI link is essential for cell coordination between eNodeBs. ODI link setup uses the self-setup procedure. Figure 3-1 Centralized Cloud BB

For details, see USU3900-based Multi-BBU Interconnection Feature Parameter Description.

3.2 USU3910-based Multi-BBU Interconnection USU3910-based multi-BBU interconnection includes centralized Cloud BB and distributed Cloud BB modes. l

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In centralized Cloud BB networking mode, the BBUs and USU are directly connected and the cable length is less than 100 m, and the USUs are also directly connected and the cable length is less than 90 m. Figure 3-2 illustrates the centralized Cloud BB networking mode.


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Figure 3-2 Centralized Cloud BB

l

In distributed Cloud BB networking mode, the BBUs and USU are directly connected through fiber optic cables and the maximum cable length is 10 km. The maximum cable length between two BBUs that transmit signals through first- and second-level USUs for service coordination is 20 km. The maximum cable length between two directly connected USUs is 10 km. Figure 3-3 illustrates the distributed Cloud BB networking mode. Figure 3-3 Distributed Cloud BB

For details, see USU3910-based Multi-BBU Interconnection Feature Parameter Description. Issue 02 (2015-08-31)


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The eX2 link is essential for cell coordination between eNodeBs. The eX2 link self-setup procedure is used. For details, see eX2 Self-Management Feature Parameter Description.

3.3 Coordination over Relaxed Backhaul In coordination over relaxed backhaul networking mode, the eX2 interface for cell coordination between eNodeBs share the transport network with the S1 and X2 interfaces, as shown in Figure 3-4. The end-to-end transmission delay must be less than 4 ms. Figure 3-4 Coordination over relaxed backhaul

The eX2 link is essential for cell coordination between eNodeBs. The eX2 link self-setup procedure is used. For details, see eX2 Self-Management Feature Parameter Description for LTE FDD.

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4

4 Service Features Supported by Cloud BB

Service Features Supported by Cloud BB

4.1 LTE FDD Features 4.1.1 LOFD-070223 UL CoMP based on Coordinated BBU l

With the multi-point joint reception solution, UL CoMP uses the antennas of two neighboring cells to jointly receive UE signals and combines these received signals. In this way, UL CoMP provides signal combining gains and interference mitigation gains.

l

UL CoMP based on Coordinated BBU uses the antennas of inter-BBU cells to jointly receive signals of a certain UE, as shown in Figure 4-1. Figure 4-1 UL CoMP based on coordinated BBU

The serving cell and coordinating cells are on different BBUs and information exchanges between these BBUs through USUs. For details, see UL CoMP Feature Parameter Description for LTE FDD.

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4.1.2 LAOFD-070202 Carrier Aggregation for 2CC based on Coordinated BBU l

Carrier aggregation (CA) enables aggregation of multiple contiguous or non-contiguous carriers to provide a wider bandwidth to increase the peak rate of a single UE.

l

Carrier Aggregation for 2CC based on Coordinated BBU enables aggregation of carriers on different eNodeBs, as shown in Figure 4-2. Figure 4-2 Inter-eNodeB CA based on coordinated BBU

For details, see Carrier Aggregation Feature Parameter Description for LTE FDD.

4.1.3 LOFD-070208 Coordinated Scheduling based Power Control (Cloud BB) Coordinated Scheduling based Power Control (Cloud BB) coordinates TTI-specific transmit power configurations in individual cells. It reduces inter-cell interference based on collaboration between scheduling and power control, as shown in Figure 4-3.

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Figure 4-3 Coordinated scheduling based power control

For details, see CSPC Feature Parameter Description for LTE FDD.

4.1.4 LAOFD-080201 Inter-eNodeB CA based on Relaxed backhaul l

CA enables aggregation of multiple contiguous or non-contiguous carriers to provide a wider bandwidth to increase the peak rate of a single UE.

l

During inter-eNodeB CA based on relaxed backhaul, cells exchange signaling messages and data through eX2 interfaces between the main control boards of eNodeBs. The main control boards can be LMPT or UMPT, as shown in Figure 4-4. Figure 4-4 Inter-eNodeB CA based on relaxed backhaul

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On live networks with relaxed backhaul requirements, inter-eNodeB CA can be deployed without requiring network reconfiguration. For details, see Carrier Aggregation Feature Parameter Description for LTE FDD.

4.1.5 LOFD-081219 UL CoMP Based on Relaxed Backhaul l


l

UL CoMP based on relaxed backhaul uses the antennas of inter-BBU cells to jointly receive signals of a certain UE as is shown in Figure 4-5. Figure 4-5 UL CoMP based on relaxed backhaul

The serving cell and coordinating cells are located on different BBUs and these BBUs exchange information through coordination over relaxed backhaul. For details, see UL CoMP Feature Parameter Description for LTE FDD.

4.1.6 LOFD-081208 Inter-eNodeB SFN Based on Coordinated BBU l

Single frequency network (SFN) allows two to seven RRUs to serve an SFN cell, changing the original cell edges into the SFN cell center. SFN mitigates the interference of control channels and traffic channels in intra-frequency networking scenarios in densely populated urban areas.

l

Inter-eNodeB SFN Based on Coordinated BBU enables the physical cells of different BBUs to be combined into one SFN cell. This feature minimizes the changes in physical connections between RRUs and BBUs when SFN networks are reconstructed, reducing onsite network operation and maintenance, as shown in Figure 4-6.

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Figure 4-6 Inter-eNodeB SFN Based on Coordinated BBU

For details, see SFN Feature Parameter Description for LTE FDD.

4.1.7 LOFD-081209 Inter-eNodeB Adaptive SFN/SDMA Based on Coordinated BBU l

Adaptive SFN/SDMA allows the RRUs serving an SFN cell to determine resource scheduling schemes based on UE attributes. It helps increase the spectral efficiency while maintaining system capacity.

l

Inter-BBU adaptive SFN/SDMA enables the physical cells of different BBUs to be combined into one SFN cell. This feature minimizes the changes in physical connections between RRUs and BBUs when SFN networks are reconstructed, reducing onsite network operation and maintenance, as shown in Figure 4-7. Figure 4-7 Inter-eNodeB Adaptive SFN/SDMA Based on Coordinated BBU

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4.1.8 LOFD-081220 Inter-BBU Clock Sharing In USU3900- or USU3910-based multi-BBU interconnection scenarios, if one of interconnected NEs has obtained the external clock source (such as GPS clock), other interconnected NEs can share this clock source through the BBU, USU3910, or USU3900. For details about inter-BBU clock sharing, see USU3910-based Multi-BBU Interconnection Feature Parameter Description and USU3900-based Multi-BBU Interconnection Feature Parameter Description.

4.2 LTE TDD Features 4.2.1 TDLOFD-001080 Inter-BBU SFN l

Single frequency network (SFN) allows two to seven RRUs to serve an SFN cell, changing the original cell edges into the SFN cell center. SFN mitigates the interference of control channels and traffic channels in intra-frequency networking scenarios in densely populated urban areas.

l

Inter-BBU SFN enables the RRUs connected to the baseband processing units in different BBUs to serve an SFN cell. This feature minimizes the changes in physical connections between RRUs and BBUs when SFN networks are reconstructed, reducing onsite network operation and maintenance, as shown in Figure 4-8. Figure 4-8 Inter-BBU SFN

For details, see SFN Feature Parameter Description for LTE TDD.

4.2.2 TDLOFD-001082 Inter-BBU Adaptive SFN/SDMA l

Adaptive SFN/SDMA allows the RRUs serving an SFN cell to determine resource scheduling schemes based on UE attributes. It helps increase the spectral efficiency while maintaining system capacity.

l

Inter-BBU adaptive SFN/SDMA enables the RRUs connected to the baseband processing units in different BBUs to serve an SFN cell. This feature minimizes the

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changes in physical connections between RRUs and BBUs when SFN networks are reconstructed, reducing onsite network operation and maintenance, as shown in Figure 4-9. Figure 4-9 Inter-BBU adaptive SFN/SDMA

For details, see SFN Feature Parameter Description for LTE TDD.

4.2.3 TDLOFD-080203 Coordinated Scheduling based Power Control (Cloud BB) Coordinated Scheduling based Power Control (Cloud BB) coordinates TTI-specific transmit power configurations in individual cells. It reduces inter-cell interference based on collaboration between scheduling and power control, as shown in Figure 4-10. Figure 4-10 Coordinated scheduling based power control

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For details, see CSPC Feature Parameter Description for LTE TDD.

4.2.4 TDLOFD-081207 UL CoMP based on Coordinated BBU l


l

UL CoMP based on Coordinated BBU uses the antennas of inter-BBU cells to jointly receive signals of a certain UE, as shown in Figure 4-11. Figure 4-11 UL CoMP based on coordinated BBU

The serving cell and coordinating cells are on different BBUs and information exchanges between these BBUs through USUs. For details, see UL CoMP Feature Parameter Description for LTE TDD.

4.2.5 TDLAOFD-081411 Inter-eNodeB DL CoMP based on Relaxed backhaul l

DL CoMP is a coordinated multi-point downlink transmission technology, which enables eNodeBs to use antennas in neighboring cells to process and transmit PDSCH data of a specific UE. This technology increases wanted signal power and mitigates inter-cell interference.

l

In inter-eNodeB DL CoMP based on relaxed backhaul, BBUs are interconnected using the existing IP RAN or PTN. Coordination data is transmitted between eNodeBs over the eX2 interface. The eX2 interface shares the transport network with the X2 interface. For details, see DL CoMP Feature Parameter Description for LTE TDD.

4.2.6 TDLOFD-081213 Inter-BBU Clock Sharing In USU3900- or USU3910-based multi-BBU interconnection scenarios, if one of interconnected NEs has obtained the external clock source (such as GPS clock), other interconnected NEs can share this clock source through the BBU, USU3910, or USU3900. Issue 02 (2015-08-31)


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For details about inter-BBU clock sharing, see USU3910-based Multi-BBU Interconnection Feature Parameter Description and USU3900-based Multi-BBU Interconnection Feature Parameter Description.

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5 Parameters

5

Parameters

There are no specific parameters associated with this feature.

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6 Counters

6

Counters

There are no specific counters associated with this feature.

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7 Glossary

7

Glossary

For the acronyms, abbreviations, terms, and definitions, see Glossary.

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8 Reference Documents

8

Reference Documents

1.

USU3910-based Multi-BBU Interconnection Feature Parameter Description for SingleRAN

2.

USU3900-based Multi-BBU Interconnection Feature Parameter Description for SingleRAN

3.

UL CoMP Feature Parameter Description for LTE FDD

4.

Carrier Aggregation Feature Parameter Description for LTE FDD

5.

CSPC Feature Parameter Description for LTE FDD

6.

eX2 Self-Management Feature Parameter Description for LTE FDD

7.

SFN Feature Parameter Description for LTE TDD

8.

CSPC Feature Parameter Description for LTE TDD

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Cloud BB Overview(SRAN10.1_02)

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