11_RN3163BEN20GLA0_HSPA+_RRM_v12

HSDPA Channels and FeaturesModule Objectives
At the end of the module you will be able to:
List the mayor data rate boosters (64QAM, MIMO & DC-HSDPA) of HSDPA in 3GPP Rel. 7/8 (RU20) and explain their principles
Explain which 3GPP Rel. 7/8 (RU20) features (DL Flexible RLC, CPC, CS Voice over HSPA) improve the spectrum efficiency
Describe the prerequisites and main parameters needed for the described HSPA+ features
* © Nokia Siemens Networks RN3163BEN20GLA0
optional Feature (ASW); RNC License Key required (ON-OFF)
HSDPA peak rate up to 21.1 Mbps
UE categories 13,14,17 & 18 supported
optional feature for UE
RAN764 HSDPA 16QAM
RAN 826 HSUPA
HS- DSCH category
max. HS-DSCH Codes
min. * Inter-TTI interval
17.4 or 23.4 Mbps
21.1 or 28 Mbps
64QAM: Channel Quality Requirements
good channel conditions required to apply / take benefit of 64QAM CQI 26 !
64QAM requires 6 dB higher SNR than 16QAM
average CQI typically 20 in the commercial networks
21 Mbps
0 Mbps
10 Mbps
14 Mbps
Tm
T2
T1
Rn
R2
R1
M transmit antennas, N receive antennas from MxN MIMO system
huge data stream (input) distributed toward m spatial distributed antennas; m parallel bit streams (Input 1..m)
Spatial Multiplexing generate parallel “virtual data pipes”
using Multipath effects instead of mitigating them
Signal from jth Tx antenna
Sj
MIMO
Processor
inverted Matrix H-1 used for recalculation
of original input data streams 1..m
Signal at ith Rx antenna
Yi
Sj
Prerequisites:
HSPA Peak Rate upgrade for RNC196 & RNC450
Flexi Rel2, UltraSite with EUBB
MIMOEnabled
RU20 (3GPP Rel. 7) introduces 2x2 MIMO with 2-Tx/2-Rx
Double Transmit on BTS side (D-TxAA), 2 receive antennas on UE side
System can operate in dual stream (MIMO) or single (SISO, non-MIMO) mode
MIMO 2x2 enables 28 Mbps peak data rate in HSDPA
28 Mbps peak rate in combination with 16QAM
64QAM: no simultaneous support of 64QAM & MIMO (not yet)
Dual-Cell HSDPA: not possible to enable MIMO & DC-HSDPA in a cell in parallel
MIMO increases single user peak data rate, overall cell capacity &
average cell throughput
UE categories for MIMO support: Cat. 15, 16, 17 & 18
Data stream 1
UE: 2 Rx-
17.4 or 23.4 Mbps
21.1 or 28 Mbps
MIMO 2x2 / 28 Mbps
Enabling MIMO in a cell / Remarks
To enable MIMO in a cell, RNC checks several other functions :
NBAPCommMode
MIMO is not supported by NB/RSxxx series
HSDPA14MbpsPerUser: “HSDPA 14 Mbps per User” feature must be enabled (1)
FDPCHEnabled: “Fractional DPCH” must be enabled (1)
FRLCEnabled: “Flexible RLC” must be enabled (1)
DCellHSDPAEnabled: “Dual-Cell HSDPA” must not be configured with MIMO in parallel (0)
HSDPA, HSUPA & HSPA related features have to be enabled for MIMO usage:
HSDPAEnabled, HSUPAEnabled (1)
HSDPADynamicResourceAllocation: HSDPA Dynamic Resource Allocation (1)
HSDPAMobility: Serving Cell Change & SHO for a-DCH has to be enabled (1)
NSN RU20 release supports MIMO for NRT PS services only
no support for CS voice & RT PS Streaming
Signalling must be mapped to HSPA (“Full HSPA configuration”)
RB mapped to HS-DSCH in DL and E-DCH in UL
SRB mapped to HS-DSCH in DL and E-DCH in UL
DC-HSDPA: Principles (1/2)
prior to 3GPP Release 8, HSDPA channel bandwidths are limited to 5 MHz
Dual-Cell HSDPA: 3GPP Rel. 8 allows 2 adjacent channels to be combined
effective HSDPA channel bandwidth of 10 MHz (RU20 feature)
3GPP Rel. 8: Dual Cell HSDPA can be combined with 64QAM but not with MIMO
(Release 9 allows combination with both, 64QAM & MIMO)
42 Mbps HSDPA peak rate
5 MHz
5 MHz
Peak Connection Throughput = 28 Mbps
1 UE, using 2 × 5 MHz RF Channels
Peak Connection Throughput = 42 Mbps
F1
F2
DC-HSDPA: Principles (2/2)
DC-HSDPA provides greater flexibility to the HSDPA Scheduler, i.e. the scheduler can allocated resources in the frequency domain as well as in the code and time domains
F1
F2
F1
F2
F1
F2
UEx
UEx
UE1
UE1
UE1
5) Improved Cell Edge
DC-HSDPA & 64QAM enable 42 Mbps peak rates in HSDPA
UE categories for MIMO support: Cat. 21, 22, 23 & 24
HW: Flexi Rel2, UltraSite with EUBB
optional feature; requires long term
RNC license for specific number of cells
following features must be enabled:
HSDPA (HSDPAEnabled)
HSUPA (HSUPAEnabled)*
HSDPA Serving Cell Change (HSDPAMobility)
Fractional DPCH (FDPCHEnabled)
Shared Scheduler for Baseband Efficiency
HSPAQoSEnabled must be configured with the same value in both DC-HSDPA cells
MaxBitRateNRTMACDFlow (def. 65535 = not restricted) should be configured to allow the peak throughput
MIMO must not be enabled for all cells belonging to the Node B (MIMOEnabled)
* at least 1 of the RF carriers
HS- DSCH category
max. HS-DSCH Codes
FRLCEnabled
included in RU20 basic software package – no license needed
HW Prerequisites: Flexi Rel2, UltraSite with EUBB
Flexible RLC used, if:
UE supports Flexible RLC
AM RLC is used
Dynamic Resource Allocation enabled
Rel. 7 Flexible RLC
16 bit RLC Header 4.8% or 2.4% Overhead
MAC-hs
• • •
adapts RLC-PDU size to
no segmentation
DL Flexible RLC
Prior to Rel7 the RLC layer segmented high layer data units (IP packets) in RLC PDU sizes of 336 and 656
336 is 320 net bit plus 16 bit RLC OH
656 is 640 net bit plus 16 bit RLC OH
On MAC-d layer did not increase Overhead
Data was passed directly to MAC-hs layer (MAC-d)
Several MAC-d PDUs were concatenated to form a MAC-hs data block
BTS selects proper MAC-hs data block size based on
available user date in BTS buffer and
radio conditions for that UE
With DL Flexible RLC the RNC adapts the RLC-PDU size to the actual size of the higher layer data unit (IP)
maximum size of 1500 Byte is supported (IP packet length in Ethernet)
Background
less processing in RNC & UE
higher end user application throughput
lower latency for packet access
Significantly lower Overhead
Much less padding bits
Lower risk for RLC stalling because of too small transmission windows
Advantages
Overhead
CS Voice over HSPA
Introduction
Discontinuous UL DPCCH Transmission & Reception during UE UL traffic inactivity
(UL DPCCH gating + DRX at BTS)
CQI reporting reduction (switched from periodical to synchronized with DPCCH burst)
Stopping E-DPCCH detection at NodeB during DPCCH inactivity
Discontinuous DL Reception (DRX at UE)
Stop receiving HS-SCCH, E-AGCH & E-RGCH when not needed
Faster response times
Increased number of low activity packet users in CELL_DCH state
Motivation and Benefits:
Longer battery life
Prerequisites:
CQI Reporting reduction
Continuous Packet Connectivity - CPC
UL Gating (UL DTX): reduces UL control channel (DPCCH) overhead
no data to sent on E-DPDCH or HS-DPCCH UE switchs off UL DPCCH
DPCCH Gating is precondition for other 3 sub-features
DPDCH
DPCCH
E-DPDCH
DPCCH
E-DPDCH
DPCCH
Rel7 Voice 2ms
Network:
UE:
required Network Features:
SRB must be mapped to HSPA
supported RAB combinations:
Speech CS RAB
Speech CS RAB + PS streaming PS RAB
Speech CS RAB + 1...3 IA/BG PS RABs
Speech CS RAB + PS Streaming PS RAB + 1...3 IA/BG PS RABs
Load based AMR selection algorithm not used while CS Voice is mapped on HSPA
Requirements
AMR (12.2, 7.95, 5.9, 4.75), (5.9, 4.75) & (12.2)
AMR-WB (12.65, 8.85, 6.6)
0 = QoS prioritization is not in use for HS transport
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
* if HSPA streaming or CS voice is activated, then QoS prioritization for NRT HSPA connections is in use, too
QoSPriorityMapping
Priority must be lower than SRB (15)
Priority must be higher than Streaming 13)
CS Voice Over HSPA
Two different voice transmission scenarios are being considered with IP:
VoIP – UE connects with network as in standard Packed Data transmission and by using “web communicators” a connection can be established
(hard to establish appropriate charging schemes)
CS voice over IP – voice is being carried by HSPA transport channels transparent for the user
Efficiency
[REF. WCDMA for UMTS – HSPA Evolution and LTE, HH AT]
Benedikt Aschermann
Rel. 7 Flexible RLC
[REF. WCDMA for UMTS – HSPA Evolution and LTE, HH AT]
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11_RN3163BEN20GLA0_HSPA+_RRM_v12