HSDPA RRM & parameters
HSDPA RRM & parameters: Module Objectives At the end of the module you will be able to: •
Explain the physical layer basics of HSDPA technology
•
List the key changes brought by HSDPA and their impact on the network and on the protocol model
•
Explain HSDPA RRM and the related parameters in detail, including packet scheduling, resource allocation, mobility and channel type selection
HSDPA RRM & parameters: Module Objectives At the end of the module you will be able to: •
Explain the physical layer basics of HSDPA technology
•
List the key changes brought by HSDPA and their impact on the network and on the protocol model
•
Explain HSDPA RRM and the related parameters in detail, including packet scheduling, resource allocation, mobility and channel type selection
HSDPA RRM: Contents • • • • • • • • • • • • • •
HSDPA Principles HSDPA Protocols & Physical Channels RU50 Capabilities & Baseband Configuration Configuration HSDPA Link Adaptation HSDPA H-ARQ HSDPA Packet Scheduling Basics of HSDPA Power Allocation Basics of HSDPA Code Allocation Basics of HSDPA Mobility HSDPA Channel Type Selection & Switching Associated UL DCH HSDPA Improvements Other Features Appendix
HSDPA Principles
HSDPAenabled WCEL; 0 = disabled; 1 = enabled
High Speed Downlink Packet Access (HSDPA) based on: • Node B decisions • Multi-code operation • Fast Link Adaptation • Adaptive Modulation & Coding AMC
• Fast Packet Scheduling • Fast H-ARQ • Fast 2 ms TTI* • Downwards Compatibility with R99 • (shared or dedicated carrier) Motivation: - enhanced spectrum efficiency
3GPP Rel. 5; TS 25.308: “HSDPA Overall Description”
- higher peak rates >> 2 Mbps - higher cell throughput - reduced delay for ACK transmission
* TTI = 1 Subframe = 3 Slots = 2 ms H-ARQ: Hybrid Automatic Repeat Request
Principles of DC HSDPA •
Dual-Cell HSDPA of 3GPP Rel8 uses two adjacent WCDMA carriers (same bandwidth) to transmit data for a single UE
•
Can be used with MIMO 2x2 and/or 64QAM
•
DC HSDPA UEs are assigned HS-PDSCHs in the primary serving cell & Secondary Serving High Speed Cell (SSHSC)
•
UL (CQI, ACK/NACK) for DC HSDPA UEs via primary serving cell (no UL in SSHSC)
•
Besides HS-DSCH the primary serving cell is carrying – –
The full set of control & comm on control channels UL transport channels E-DCH HS-DPDCH + optional DC HS-DPCCH (HSUPA UEs)
• SSHSC is left clean from control signaling (max. HS-DSCH capacity) – Among common channels only CPICH is used in SSHSC – E-AGCH, E-RGCH, E-HICH in SSHSC existent but not used by DC HSDPA
Primary serving cell DCellHSDPAEnabled WCEL; 0 = disabled; 1 = enabled
f1
f2 SSHSC
Adaptive Modulation & Coding (1/2) HSDPA uses • QPSK • 16QAM • 64QAM*
16QAM
dynamically based on quality of the radio link
QPSK 2-Bit Keying
4-Bit Keying
0100
1100
0101
1101
Q
1000
0000
Q (0,1)
(1,1)
1001
0001
I
I (0,0)
(1,0)
* defined in 3GPP Rel. 7 / implemented with NSN RU20
0111
1111
1011
0011
0110
1110
1010
0010
Adaptive Modulation & Coding (2/2)
Turbo Coding 1/3 HSDPA Adaptive Coding • based on the R’99 1/3 Turbo Coding • Rate Matching: Puncturing or Repetition code rate: 1/6 – 4/4
Rate Matching Puncturing / Repetition
• dynamically based on quality of the radio link
Effective Code Rate: 1/4 - 3/4
Multi Code Operation (1/3) SF = 1
2
4
8 C8,0 = [11111111]
C4,0 = [1111] C8,1 = [1111-1-1-1-1]
SF = 16
...
256
512
C16,0 = [.........] C16,1 = [.........] C16,2 = [.........] C16,3 = [.........]
C2,0 = [11] C8,2 = [11-1-111-1-1] C4,1 = [11-1-1] C8,3 = [11-1-1-1-111] C1,0 = [1] C8,4 = [1-11-11-11-1] C4,2 = [1-11-1] C8,5 = [1-11-1-11-11] C2,1 = [1-1] C8,6 = [1-1-111-1-11] C4,3 = [1-1-11] C8,7 = [1-1-11-111-1]
C16,4 = [.........]
SF = 16
C16,5 = [.........]
240 ksymb/s
C16,6 = [.........] C16,7 = [.........] C16,8 = [.........] C16,9 = [.........] C16,10 = [........] C16,11 = [........] C16,12 = [........] C16,13 = [........] C16,14 = [........] C16,15 = [........]
Multi-Code operation:
1..15 codes 0.24 .. 3.6 Msymb/s
Multi Code Operation (2/3) Modulation
QPSK
16QAM
64QAM
Coding rate
5 codes
10 codes
15 codes
1/4
600 kbps
1.2 Mbps
1.8 Mbps
2/4
1.2 Mbps
2.4 Mbps
3.6 Mbps
3/4
1.8 Mbps
3.6 Mbps
5.4 Mbps
2/4
2.4 Mbps
4.8 Mbps
7.2 Mbps
3/4
3.6 Mbps
7.2 Mbps
10.8 Mbps
4/4
4.8 Mbps
9.6 Mbps
14.4 Mbps
3/4
5.4 Mbps
10.8 Mbps
16.2 Mbps
5/6
6.0 Mbps
12.0 Mbps
18.0 Mbps
4/4
7.2 Mbps
14.4 Mbps
21.6 Mbps
RU20 includes 3GPP Rel. 7 features: • 64QAM (RAN1643)
HSDPA64QAMAllowed WCEL; 0 (Disabled), 1 (Enabled)
64QAM 6 bits/symbol
Multi Code Operation (3/3): HSDPA UE capability classes RU20/30 include 3GPP Rel. 7/8 features: • 64QAM (cat 13, 14, 17, 18) • 2x2 MIMO (Dual-Stream MIMO) (cat 15, 1 6, 17, 18) MIMO w/- 64QAM (cat 19, 20) • DC-HSDPA (cat 21, 22) • DC –HSDPA w/- 64QAM (cat 23, 24)
RU40 include 3GPP Rel.9 features: • DC –HSDPA w/-MIMO w/o 64QAM (cat 25, 26) • DC –HSDPA & MIMO & 64QAM (cat 27, 28) HSDPA64QAMAllowed
Modulation
DualStream MIMO supported
Peak Rate
3 (6 ms)
QPSK/16QAM
No
1.2 Mbps
5
3
QPSK/16QAM
No
1.2 Mbps
3
5
2 (4 ms)
QPSK/16QAM
No
1.8 Mbps
4
5
2
QPSK/16QAM
No
1.8 Mbps
5
5
1 (2 ms)
QPSK/16QAM
No
3.6 Mbps
6
5
1
QPSK/16QAM
No
3.6 Mbps
7
10
1
QPSK/16QAM
No
7 Mbps
8
10
1
QPSK/16QAM
No
7 Mbps
9
15
1
QPSK/16QAM
No
10 Mbps
10
15
1
QPSK/16QAM
No
14 Mbps
11
5
2
QPSK only
No
1 Mbps
12
5
1
QPSK only
No
1.8 Mbps
13
15
1
QPSK/16QAM/ 64QAM
No
17.4 Mbps
14
15
1
QPSK/16QAM/ 64QAM
No
21.1 Mbps
15
15
1
QPSK/16QAM
Yes
23.4 Mbps
16
15
1
QPSK/16QAM
Yes
28 Mbps
17
15
1
QPSK/16QAM/ 64QAM or Dual-Stream MIMO
17.4 or 23.4 Mbps
18
15
1
QPSK/16QAM/ 64QAM or Dual-Stream MIMO
21.1 or 28 Mbps
max. No. of HS-DSCH Codes
min. * Inter-TTI interval
1
5
2
HS- DSCH
category
WCEL; 0 (Disabled), 1 (Enabled)
MIMOEnabled WCEL; 0 (Disabled), 1 (Enabled)
Further details on HS-DSCH categories & other parameters HSPA+ RRM * TTI: Transmission Time Interval
Network Modifications for HSDPA new Node B functionalities: • Acknowledged transmission: Fast H-ARQ UTRAN & UE: • modified PHY layer • modified MAC
faster retransmission / reduced delays ! less Iub retransmission traffic ! higher spectrum efficiency !
• Fast Packet Scheduling fast & efficient resource allocation !
• Fast Link Adaptation Adaptive Modulation & Coding ! compensation of fast fading (without fast PC) higher peak rates & spectrum efficiency !
Uu • modified transport and physical channels
Iub
RNC: functionalities shifted to Node B
r e t r R a n e s d m u i c e s s d i o n
• modified coding • modified modulation
Node B „more intelligence“ new functionalities
UE new UEs
HSDPA
Capability Classes
HSDPA RRM • • • • • • • • • • • • • •
HSDPA Principles HSDPA Protocols & Physical Channels RU50 Capabilities & Baseband Configuration HSDPA Link Adaptation HSDPA H-ARQ HSDPA Packet Scheduling Basics of HSDPA Power Allocation Basics of HSDPA Code Allocation Basics of HSDPA Mobility HSDPA Channel Type Selection and Switching Associated UL DCH HSDPA Improvements Other Features Appendix
HSDPA Protocol Model RLC
RLC DCH
MAC-d
R99 PHY
UE
HSDPA (R5) HSDPA (R7)
DPCH
Uu
RLC
PHY UE
DCH FP
DCH FP
TNL
TNL
Node B
Iub
HS-DSCH HS-PDSCH Uu
RNC
RLC
MAC-d flow
MAC-d MAC-hs MAC-ehs
PHY
MAC-d
MAC-d
MAC-hs MAC-ehs
HS-DSCH FP
HS-DSCH FP
PHY
TNL
TNL
Node B
Iub
(e)hs: (enhanced) high speed TNL : Transport Network Layer
RNC
Concepts of MAC Layer, MAC-hs & MAC-ehs MAC: Medium Access Control MAC • •
25.321
Mapping of logical channels onto transport channels Multiplexing of multiple logical channels onto a single transport channel, e.g. of 4 signalling radio bearers (SRB) onto single DCH
• • •
TS
Complete MAC multiplexing for user plane data currently not supported Multiplexing requires the addition of a MAC header
MAC entities on network side distributed between RNC and Node B
MAC-hs • •
•
•
supports HSDPA with 3GPP Rel. 5 Tasks of MAC-hs within the Node B • Flow control (see section packet scheduling) • Packet scheduling (see section packet scheduling) • H-ARQ (see section layer 1 re-transmission) • Transport format selection (see section link adaptation) Tasks of MAC-hs within the UE • HARQ (see section layer 1 re-transmission) • Disassembly of transport blocks • Re-ordering Header & payload • Payload: Concatenating of one or more MAC-d PDU into single MAC-hs PDU • Header: 21 bits assuming single MAC-d PDU size
MAC-ehs • •
supports enhanced HS-DSCH functions of 3GPP Rel. 7 - 9 must be configured to support features such as: 64QAM (RAN1643), MIMO (RAN 1642), flexible RLC (RAN1638), Dual-Cell HSDPA (RAN1906)
Physical Channel Overview
HS-PDSCH High-Speed Physical DL Shared Channel
HS-SCCH High Speed Shared Control Channel
HS-DPCCH High Speed Dedicated Physical Control Channel
Node B
associated DCH Dedicated Channel (Rel. 99)
MAC-hs
F-DPCH Fractional Dedicated Physical Channel (Rel. 6/7)
HS-PDSCH • HS-PDSCH: High-Speed Physical Downlink Shared Channel • • • • •
•
Transfer of actual HSDPA data 5 - 15 code channels QPSK or 16QAM modulation Divided into 2 ms TTIs Fixed SF16
HS-PDSCH code set parameter •
Specifies whether number of codes channels reserved for HSDPA is fixed* or dynamically adjustable
• •
Minimum 5 code channels / Maximum 15 codes channels Possible numbers of code channels enabled / disabled bit wise
HSPDSCHCodeSet HS-PDSCH code set; WCEL; (-) (-) (5 codes) Examples 00000 00000 100000 = always 5 codes reserved (default) 11010 10100 100000 = number of reserved codes adjustable (5, 8, 10, 12, 14 or 15 codes, recommended) 11-15 codes
6-10 codes
0-4 codes always disabled
HS-SCCH (1/2) • HS-SCCH: High-Speed Shared Control Channel •
L1 Control Data for UE; informs the UE how to decode the next HS -PDSCH frame e.g. UE Identity, Channelization Code Set, Modulation Scheme, TBS, H-ARQ process information Fixed SF128 transmitted 2 slots in advance to HS-PDSCHs NSN implementation with slow power control: shares DL power with the HS-PDSCH more than 1 HS-SCCH required when code multiplexing is used
• • • •
MaxNbrOfHSSCCHCodes
• Code multiplexing
Maximum number of HS-SCCH codes
WCEL; RU10 & earlier: 1..3; 1; 1; RU20: 1..4
SF16 HS-PDSCH 15
User 1
User 2
Subframe 2 ms
User 3
•
HSDPA service for several users simultaneously
•
For each user individual HS-SCCH required
•
available only, if > 5 codes can be reserved for HS-PDSCH
User 4
10
5
TBS: Transport Block Size
Time
HS-SCCH (2/2)
+15 x SF16 HS-PDSCH
SF16
SF32
32
SF64
64
64
64
S-CCPCH1 SF128
SF256
128
256
256
128
128
S-CCPCH2
HS-SCCH
256
256
256
256
256
CPICH AICH P-CCPCH PICH 128
128
Allocated CC
Blocked CC
FACH-s: for Service Area Broadcast (CTCH)
128
Available CC
128
256
128
256
256
256
128
128
HS-SCCH
HS-SCCH
256
256
256
256
HS-DPCCH • UL HS-DPCCH: High-Speed Dedicated Physical Control Channel • • •
MAC-hs Ack/Nack information (send when data received) Channel Quality Information (CQI reports send every 4ms, hardcoded period) Fixed SF 256
1 Slot = 2560 chip HARQ-ACK (10 bit)
2 Slots = 5120 chip CQI (20 bit) Channel Quality Indication
1 HS-DPCCH Subframe = 2ms
Subframe # 0
Subframe # i
TS 25.21: CQI values = 0 (N/A), 1 .. 30; steps: 1; 1 indicating lowest, 30 highest air interface quality
Subframe # N
HS-DPCCH & CQI
CQI
P-CPICH UE observes P-CPICH (Ec/Io) CQI*
TB Size
# codes Modulation
1
137
1
QPSK
0
2
173
1
QPSK
0
3
233
1
QPSK
0
4
317
1
QPSK
0
5
377
1
QPSK
0
6
461
1
QPSK
0
7
650
2
QPSK
0
8
792
2
QPSK
0
9
931
2
QPSK
0
10
1262
3
QPSK
0
11
1483
3
QPSK
0
12
1742
3
QPSK
0
13
2279
4
QPSK
0
14
2583
4
QPSK
0
15
3319
5
QPSK
0
CQI used for:
16
3565
5
16-QAM
0
• Link Adaptation decision • Packet Scheduling decision
17
4189
5
16-QAM
0
18
4664
5
16-QAM
0
19
5287
5
16-QAM
0
ACK/NACK used for:
20
5887
5
16-QAM
0
21
6554
5
16-QAM
0
22
7168
5
16-QAM
0
• H-ARQ process • Link Adaptation decision • HS-SCCH power adaptation * UE internal (proprietary) process TB Size [bit] CQI value 0: N/A (Out of range) = Reference Power Adjustment (Power Offset) [dB]
CQI Table (Example) TS 25.214: Annex Table 7b
Cat 8 UE
23
9719
7
16-QAM
0
24
11418
8
16-QAM
0
25
14411
10
16-QAM
0
26
14411
10
16-QAM
-1
27
14411
10
16-QAM
-2
28
14411
10
16-QAM
-3
29
14411
10
16-QAM
-4
CQI Tables TS 25.214: Annex Table 7d Cat 10 UE
TS 25.214: Annex Table 7f Cat 27 UE
TS 25.214 Annex Table 7g Cat 14 UE: CQI29: 14 Codes; 32257 bit CQI30: 15 Codes; 38582 bit
CQI
TB Size
# codes Modulation
CQI
TB Size
# codes Modulation
1
137
1
QPSK
0
1
136
1
QPSK
0
2
173
1
QPSK
0
2
176
1
QPSK
0
3
233
1
QPSK
0
3
232
1
QPSK
0
4
317
1
QPSK
0
4
320
1
QPSK
0
5
377
1
QPSK
0
5
376
1
QPSK
0
6
461
1
QPSK
0
6
464
1
QPSK
0
648
2
QPSK
0
7
650
2
QPSK
0
7
8
792
2
QPSK
0
8
792
2
QPSK
0
9
931
2
QPSK
0
9
928
2
QPSK
0
10
1262
3
QPSK
0
10
1264
3
QPSK
0
11
1483
3
QPSK
0
11
1488
3
QPSK
0
12
1742
3
QPSK
0
12
1744
3
QPSK
0
13
2279
4
QPSK
0
13
2288
4
QPSK
0
14
2583
4
QPSK
0
14
2592
4
QPSK
0
15
3319
5
QPSK
0
15
3328
5
QPSK
0
16
3565
5
16-QAM
0
16
3576
5
16-QAM
0
17
4189
5
16-QAM
0
17
4200
5
16-QAM
0
18
4664
5
16-QAM
0
18
4672
5
16-QAM
0
19
5287
5
16-QAM
0
19
5296
5
16-QAM
0
20
5887
5
16-QAM
0
20
5896
5
16-QAM
0
21
6554
5
16-QAM
0
21
6568
5
16-QAM
0
22
7168
5
16-QAM
0
22
7184
5
16-QAM
0
23
9719
7
16-QAM
0
23
9736
7
16-QAM
0
24
11418
8
16-QAM
0
24
11432
8
16-QAM
0
25
14411
10
16-QAM
0
25
14424
10
16-QAM
0
26
17237
12
16-QAM
0
26
15776
10
64-QAM
0
27
21754
15
16-QAM
0
27
21768
12
64-QAM
0
28
23370
15
16-QAM
0
28
26504
13
64-QAM
0
29
24222
15
16-QAM
0
29
32264
14
64-QAM
0
30
25558
15
16-QAM
0
30
32264
14
64-QAM
-2
Associated DCH (DL & UL) • DL DPCH: Associated Dedicated Physical Channel • L3 signalling messages • Speech - AMR • Power control commands for associated UL DPCH
• UL DPCH: (DPDCH & DPCCH) • L3 signalling messages • Transfer of UL data 16 / 64 / 128 / 384 kbps, e.g. TCP acknowledgements
• Speech - AMR DPDCH / DPCCH (time multiplexed) DPDCH: L3 signalling; AMR DPCCH: TPC for UL DPCH power control
DPDCH: L3 signalling, AMR; TCP ACKs; 16 / 64 / 128 / 348 kbps
DPCCH: TPC, Pilot, TFCI
Fractional DPCH: F-DPCH (DL) The Fractional DPCH (F-DPCH):
• introduced in 3GPP Rel. 6 (enhanced in Rel. 7; NSN RU20 implementation based on Rel. 7) • replaces the DL DPCCH • includes T r a n s m i t P o w e r C o n t r o l ( TP C ) b i t s but excludes TFCI & Pilot bits & SRB – TFCI bits - no longer required as there is no DPDCH – Pilot bits - no longer required as TPC bits are used for SIR measurements – SRB mapped to E-DCH & HS-DSCH
• increases efficiency by allowing up to 10 UE to share the same DL SF256 channelization code -
time multiplexed one after another
• RU20 feature RAN1201 ; – – – –
requires Rel. 7 or newer UE HSDPA & HSUPA must be enabled Feature is licensed using an RNC ON/OFF license License CPC exists and its state is ON
FDPCHEnabled WCEL; 0 (Disabled), 1 (Enabled)
1 time slot 2560 chips 256 chips Tx Off
TPC
Tx Off
Slot #i
HSDPA RRM • • • • • • • • • • • • • •
HSDPA Principles HSDPA Protocols & Physical Channels RU50 Capabilities & Baseband Configuration HSDPA Link Adaptation HSDPA H-ARQ HSDPA Packet Scheduling Basics of HSDPA Power Allocation Basics of HSDPA Code Allocation Basics of HSDPA Mobility HSDPA Channel Type Selection and Switching Associated UL DCH HSDPA Improvements Other Features Appendix
Summary Characteristic
RU10
RU20
RU30
RU40/RU50
HSDPA users per cell
≤ 64
≤ 72 (RAN1668)
≤ 72
≤ 128 (RAN2124)
Modulation
QPSK/16QAM
QPSK/16QAM & 64QAM (RAN1643)
QPSK/16QAM/64QAM
QPSK/16QAM/64QAM
MIMO
No
Yes (2x2) (RAN1642)
Yes
Yes
Dual-Cell HSDPA
No
Yes (RAN1906)
DC-HSDPA
DC-HSDPA DB DC HSDPA (RAN2179)
Data rate per UE
up to 14 Mbps
up to 42 Mbps
up to 42 Mbps 84 Mbps (RAN 1907)
up to 84 Mbps (RAN1907)
Traffic Classes
Interactive + Background + Streaming
+ CS Voice over HSPA (RAN1689)
all traffic classes
Packet Scheduler
Proportional Fair (PF) + QoS Aware HSPA Scheduling
PF + QoS aware sc heduling
PF + QoS aware scheduling
HSDPA Multi-RAB
multiple RAB HSDPA + AMR
multiple RAB HSDPA + AMR
multiple RAB HSDPA + AMR, +CS64 Conv.
Yes (up to 3)
Yes (up to 4)
Yes (up to 4)
Yes (up to 4)
16, 64, 128, 384 Kbps
16, 64, 128, 384 Kbps
16, 64, 128, 384 Kbps
16, 64, 128, 384 Kbps
Code Multiplexing (Scheduled users per TTI)
UL associated DCH
all traffic classes PF + QoS aware scheduling multiple RAB HSDPA + AMR, +CS64 Conv.
Feature Activation • Most enhanced features must be licensed individually and are activated by setting individual off / on parameter • Some features can be activated on cell level, ot hers on WBTS or even RNC level only HSDPAenabled
HSDPAMobility
WCEL; 0 = disabled; 1 = enabled
Serving HS-DSCH cell change & SHO on/off switch RNFC ; 0 = disabled; 1 = enabled
HSDPA48UsersEnabled RNFC; 0 = disabled; 1 = enabled
HspaMultiNrtRabSupport
HSDPA64UsersEnabled
HSPA multi RAB NRT support WCEL; 0 = disabled; 1 = enabled
WCEL; 0 = disabled; 1 = enabled
HSDPA14MbpsPerUser
HSDPADynamicResourceAllocation
WBTS; 0 = disabled; 1 = enabled
HSDPA Dynamic Resource Allocation RNFC; 0 = disabled; 1 = enabled
HSPAQoSEnabled
HSDPA16KBPSReturnChannel
WCEL; 0..4; 1; 0 = disabled 0 = QoS prioritization is not in use for HS t ransport 1 = QoS prioritization is used for HS NRT channels 2 = HSPA streaming is in use 3 = HSPA CS voice is in use 4 = HSPA streaming & CS voice are in use
RU20/ 30 RU40
HSPA72UsersPerCell WCEL; 0 = disabled; 1 = enabled if enabled, max. 72 HSDPA/HSUPA users can be supported per cell.
HSPA128UsersPerCell WCEL; 0 = disabled; 1 = enabled if enabled, max. 128 HSDPA/HSUPA users can be supported
HSDPA 16 Kbps UL DCH return channel on/off RNFC; 0 = disabled; 1 = enabled
FDPCHEnabled; CPCEnabled WCEL; 0 (Disabled), 1 (Enabled)
HSDPA64QAMAllo wed; MIMOEnabled; DCellHSDPAEnabled; MIMOWith64QAMUsage WCEL; 0 (Disabled), 1 (Enabled)
DCellAndMIMOUsage WCEL; 0=DC-HSDPA and MIMO disabled; 1=DC-HSDPA and MIMO w/o 64QAM enabled; 2=DC-HSDPA and MIMO with 64QAM enabled
Cell Group Definition • SCHs under the same Node B should not overlap with each other • define for each sector offset relative to BTS frame number with parameter Tcell • Cells with offsets within certain range form one cell group – – – –
Group 1 offset = 0-512 chips Group 2 offset = 768-1280 chips Group 3 offset = 1536-2048 chips Group 4 offset = 2304 chips
BTS reference
BTS reference SCH
0 chips
SCH 256 chips
BTS reference SCH
512 chips
Tcell Frame timing offset of a cell WCEL; 0..2304 chips; 256 chips; no default
HSPA 72 / 128 Users per Cell (1/3) • • • • •
HSPA 72 users/cell: RAN1686 (RU20); HSPA 128 users/cell: RAN2124 (RU40); optional RNC License Key required (On-Off) HSPA72UsersPerCell increases the number of simultaneous HSPA users to 72 / 128 per cell WCEL; 0 = not enabled; 1 = enabled both with dedicated & shared scheduler HSDPA, HSUPA, Dynamic Resource Allocation must be enabled, Continuous Packet Connectivity & F -DPCH are recommended for both RAN1686 & RAN2124, HSUPA DL Physical Channel Power Control recommended for RAN2124 HSPA128UsersPerCell • max. 15 codes allocated (HS-PDSCH code set = 11010 10100 10000) WCEL; 0 = not enabled; 1 = enabled • Code multiplexing (max. no. of HS-SCCH codes MaxNbrOfHSSCCHCodes = 4) • HSDPA 16 Kbps UL DCH should be enabled to avoid UL overload
72 /128 users
72 /128 users
Hardware requirements: • Flexi Node B must have Rel2 or Rel3 system module 72 /128 users
Other parameters may restrict max. number of HSPA users, e.g.: -WCEL: MaxNumberEDCHCell - WBTS: MaxNumberEDCHLCG - WCEL: MaxNumberHSDSCHMACdFlows - WCEL: MaxNumberHSDPAUsers - WCEL: MaxNumbHSDPAUsersS - WCEL: MaxNumbHSDSCHMACdFS
HSPA 72 / 128 Users Per Cell (2/3) DL Code allocation DL Code allocation in a cell depends on activated features and t raffic – if HSPA 72 Users Per Cell or HSPA 128 Users Per Cell is enabled, RNC allocates DL codes according to Maximum number of scheduled HSDPA user per TTI (Code Multiplexing)
MaxNbrOfHSSCCHCodes ; WCEL; 1..4; 1; 1 (4 is recommended in both cases)
– 1 E-RGCH & E-HICH codes is reserved in cell setup; max number of E -RGCH/E-HICH codes is 4 or not limited
reserved number of E-RGCH/E-HICH codes depend on number of HSUPA users, TTI (2ms or 10ms), whether the cell is serving or non-serving E-DCH cell to the UE, and scheduled or non-scheduled transmission
– if Paging 24 kbps feature is enabled, more DL codes are needed to separate FACH and PCH traff ic
; WCEL; on/ o ff & NbrOfSCCPCHs ; WCEL; 1..3; 1; 1 PCH24kbpsEnabled SF 16,0 SF 32 S-CCPCH SF 64
E-RGCH E-HICH
HS-SCCH
SF 128
SF 256 0
1
2
3
4
5
6
depending on FACH / PCH configuration
7
8
9
10
11
12
13
14
15
HSPA 72 / 128 Users Per Cell (3/3) Traffic analysis
MaxNbrOf HSSCCHCodes WCEL; RU10 & earlier: 1..3; 1; 1; RU20: 1..4
• No. of HS-SCCH channels increased to 4 to schedule & control increased number of HSPA users in a cell • DL code space limited dynamic DL control channel allocation mechanism introduced to maximize available codes for HS-PDSCHs HSUPA RRM (E-RGCH & E-HICH management / dynamic code allocation) • if code tree resources allocated like on previous slide, following traffic is supported: – – – –
15 codes @ SF16 for HSDPA single user per 2 ms TTI (no code multiplexing) MIMO enabled F-DPCH enabled
• m o s t l i k el y RNC will allocate another SF16 branch to increase control channel traffic r e d u c i n g H S DP A SF16 co des further
Code allocation in case of 4 HS-SCCH:
HSDPA RRM • • • • • • • • • • • • • •
HSDPA Principles HSDPA Protocols & Physical Channels RU50 Capabilities & Baseband Configuration HSDPA Link Adaptation HSDPA H-ARQ HSDPA Packet Scheduling Basics of HSDPA Power Allocation Basics of HSDPA Code Allocation Basics of HSDPA Mobility HSDPA Channel Type Selection and Switching Associated UL DCH HSDPA Improvements Other Features Appendix
CQI Reporting & Link Adaptation Remember:
P-CPICH
CQI used for:
UE observes P-CPICH (Ec/Io) CQImeasured*
• Link Adaptation decision • Packet Scheduling decision
ACK/NACK used for: • H-ARQ process • Link Adaptation decision • HS-SCCH power adaptation
Link adaptation algorithm
1) Generation of CQImeasured : – –
CQImeasured*
UE monitors EC /I0 UE reads PHS-PDSCH SIG (L3/RRC signalling)
2) UE reports CQImeasured every 4 ms (NSN solution) – can be increased with Mass Event Eandler 3) CQI Correction in Node B Node B corrects reported CQImeasured to CQIcompensated based on: actual HS-PDSCH power PHS-PDSCH TRUE Number of ACK & NACK
– –
4) Link Adaptation decision: Node B decides about TB size for next sub-frame: – – –
Modulation Coding rate Number of codes
* UE internal (proprietary) process
