Date post: | 03-Feb-2016 |
Category: |
Documents |
Upload: | lavezzi-detto |
View: | 15 times |
Download: | 4 times |
Slide titleIn CAPITALS
50 pt
Slide subtitle 32 pt
HSDPA Overview
Christofer LindheimerWRAN System Management
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-272
Outline
HSDPA Principles HSDPA Channels and Bearers
– Power Setting of new channels
Capacity Management HS-DSCH Mobility Flow Control & Transport Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-273
What is High Speed Downlink Packet Access (HSDPA)
STANDARDIZED Integral part of WCDMA (3GPP Release 5)
REDUCED DELAY Reduced round trip time
CAPACITY 2 – 3 times improved system throughput
SPEED Higher bit rates: up to 14 Mbps
Smooth Upgrade Short time to market with existing sites
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-274
Key Idea in HSDPA
Fast adaptation of transmission parameters to fast variations in radio conditions
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-275
Shared Channel Transmission
HSDPA data channel is called HS-DSCH A set of radio resources dynamically shared among multiple users
– In the time domain– In the code domain
Channelization codes allocatedfor HS-DSCH transmission
8 codes (example)SF=16
SF=8
SF=4
SF=2
SF=1
User #1 User #2 User #3 User #4
TTI
Shared channelization
codes
User #5 (CODE MUX!)
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-276
Short TTI (2 ms)
Reduced air-interface delay– Improved end-user performance– Required by TCP at high data rates
Increases benefit from other HS-DSCH features– Fast Link Adaptation– Fast hybrid ARQ with soft combining– Fast Channel-dependent Scheduling
10 ms20 ms40 ms
Earlier releases
2 msRel 5 (HS-DSCH)
2 ms
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-277
Higher Order Modulation
16 QAM to be used when radio quality is good– E.g., close to base stations
Enables higher rates
16QAM
2 bits/symbol 4 bits/symbol
QPSK
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-278
Fast Link Adaptation
Adjust transmission parameters to match instantaneous channel conditions
HS-DSCH: Rate control– Based on Quality reports from UE
(CQI= Channel Quality Indicator)– Adaptive coding rate– Adaptive modulation– Adapt on 2 ms TTI basis– Use “available power”
Compare– Release 99: Power control (constant
rate)
Good channelconditions
high data rate
Bad channelconditions
low data rate
rate adaptation
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-279
Dynamic Power Allocation
Dedicated channels (power controlled)
Common channels
Power usage with dedicated channelst
Unused power
Power
HS-DSCH with dynamic power allocationt
Dedicated channels (power controlled)
Common channels
HS-DSCH (rate controlled)
Total cell power
Power
Total cell power
3GPP Release 99 3GPP Release 5
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2710
Fast channel-dependent Scheduling
Scheduling = which UE to transmit to at a given time instant and at what rate
Basic idea: transmit at fading peaks– Tradeoff: fairness vs cell throughput
high data rate
low data rate
Time
#2#1 #2 #2#1 #1 #1
User 2
User 1
Scheduled user
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2711
Fast channel-dependent Scheduling Examples of scheduling algorithms
– Round Robin (RR) Cyclically assign the channel to users Channel quality variance unexplored
– Proportional Fair (PF) Assign the channel to the user with the best relative
channel quality Improved cell throughput
– Max C/I Ratio Assign the channel to the user with the best channel
quality High system throughput but not fair
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2712
P1,1
+
AC
K
Fast Hybrid ARQ with Soft Combining Rapid retransmissions of erroneous data
– Hybrid ARQ protocol terminated in RBS short RTT
– Soft combining in UE of multiple transmission attempts reduced error rates for RLC retransmissions
NA
CK
P1,2
P1,2
P2,1P1,1
P1,1 P2,1
NA
CK
P2,2
P2,2
AC
K
P3,1
AC
K
P2,1 P3,1
+
Transmitter
Receiver
RTT
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2713
HSDPA Basic Principles
Shared Channel TransmissionDynamically shared in time & code
domain
Higher-order Modulation16QAM in complement to QPSK for
higher peak bit rates
2 ms
Short TTI (2 ms)Reduced round trip delay
Fast Hybrid ARQ with Soft Combining
Reduced round trip delay
Fast Radio Channel Dependent Scheduling
Scheduling of users on 2 ms time basis
Fast Link AdaptationData rate adapted to radio
conditions on 2 ms time basis
t
P
Dynamic Power AllocationEfficient power &
spectrum utilisation
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2714
Node Impacts
RBS– HS-DSCH functionality
Scheduling, Link Adaptation, Hybrid ARQ…- …all implemented in RBS
RNC– Impact
Setup of HS-DSCH/HS-SCCH Setup of users on HS-DSCH Capacity Management, Cell change handling
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2715
Outline
HSDPA Principles HSDPA Channels and Bearers
– Power Setting of new channels
Capacity Management HS-DSCH Mobility Flow Control & Transport Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2716
HSDPA Channel Structure
RBS ARBS A
High-Speed Downlink Shared Channel – HS-DSCH-High-Speed Physical Downlink Shared Channel – HS-PDSCH : DL Data
HS-PDSCH
-High-Speed Shared Control Channel – HS-SCCH: Scheduling
HS-SCCH
Associated Dedicated Channel- A-DCH: Data in UL and control in DL
RBS BRBS BRBS B
A-DCH
-Multiplexed with High-Speed Dedicated Physical Control Channel: ACK/NACK + CQI
HS-DPCCH
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2717
HS-DSCH and A-DCH
Shared channel:– HS-DSCH
Per HS-DSCH user:– A-DCH DL
3.4 kbps SRB (control signalling) Also needed for power controlling the UL
– A-DCH UL 64 (or 384) kbps DCH 3.4 kbps SRB (control signalling) High-Speed Dedicated Physical Control Channel
(HS-DPCCH)
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2718
HS-DPCCH and HS-SCCH power
HS-DPCCH (UL)– ACK, NACK, CQI
Power offsets in relation to DPCCH Repetition of ACK, NACK, CQI based on performance
HS-SCCH (DL)– Fixed Power (relative to CPICH)
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2719
UE capabilities
HS-DSCH category
Maximum number of HS-DSCH
codes received
Minimum inter-TTI interval
Maximum number of bits of an HS-DSCH
transport block received within
an HS- DSCH TTI
Total number of
soft channel bits
Modulation
Category 1 5 3 7298 19200 QPSK/16QAM Category 2 5 3 7298 28800 QPSK/16QAM Category 3 5 2 7298 28800 QPSK/16QAM Category 4 5 2 7298 38400 QPSK/16QAM Category 5 5 1 7298 57600 QPSK/16QAM Category 6 5 1 7298 67200 QPSK/16QAM Category 7 10 1 14411 115200 QPSK/16QAM Category 8 10 1 14411 134400 QPSK/16QAM Category 9 15 1 20251 172800 QPSK/16QAM Category 10 15 1 27952 172800 QPSK/16QAM Category 11 5 2 3630 14400 QPSK Category 12 5 1 3630 28800 QPSK
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2720
HSDPA Services and RABs first HSDPA release
New RABs– PS Interactive
64/HS – PS Interactive
384/HS 16QAM is optional 1–5 HS-PDSCH
codes (configurable) All HS capable UEs
use HSDPA regardless of CN requested bit-rate
Theoretical max: BLER operating level 10 % will decrease values accordingly
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2721
Outline
HSDPA Principles HSDPA Channels and Bearers
– Power Setting of new channels
Capacity Management HS-DSCH Mobility Flow Control & Transport Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2722
Admission control
Load non
-gua
ran
tee
d /
non
-han
dove
r
non
-gua
ran
tee
d /
hand
ove
r
gua
rant
eed
/ no
n-ha
ndov
er
gua
rant
eed
/ ha
ndov
er
Admission Granted
Admission Rejected
Admission thresholds varies depending on:
– Request class Guaranteed
- Conversational- Streaming
Non-guaranteed- Interactive- Background
– Request type Handover Non-handover
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2723
Admission control
Power non
-gua
ran
tee
d /
non
-han
dove
r
non
-gua
ran
tee
d /
hand
ove
r
gua
rant
eed
/ no
n-ha
ndov
er
gua
rant
eed
/ ha
ndov
er
A-D
CH
/
non-
hand
over
A-D
CH
/
hand
over
Admission Granted
Admission RejectedCongestion threshold
Handover thresholdGuaranteed threshold
Non-guaranteed threshold
High load situations should still allow for access to remaining
power
MAX number of HS-DSCH users criterion
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2724
Congestion control
Cell(s)
CongestionControl
AdmissionControl
“DL Congestion”Block ALL new requests
Start congestion resolve actions in the cellPeriodically:•Downswitch non-guaranteed users to Cell_FACH•Downswitch HS-users to idle state•Drop guaranteed usersMost resource-consuming users are targeted first
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2725
Outline
HSDPA Principles HSDPA Channels and Bearers
– Power Setting of new channels
Capacity Management HS-DSCH Mobility Flow Control & Transport Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2726
RNC RNCIur
Iub Iub
Iu Iu
Associated Dedicated ChannelsHS-PDSCHHS-SCCH
HS-DPCCH
•Serving HS-DSCH Cell Selection (Intra and Inter-Frequency)
•No Soft/Softer HO for HS-DSCH
•Serving HS-DSCH Cell Change (Intra-RNC)
Iub
Overview of HSDPA Mobility
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2727
Serving HS-DSCH Cell Change, -Mobility
The following events will trigger a serving HS-DSCH cell change
– A change of best cell within AS (event 1d)– SHO removal (event1b) – SHO replacement (event 1c)
RNC RNCIur
Iub Iub
Iu Iu
Associated Dedicated ChannelsHS-DSCHHS-SCCH
HS-DPCCH
Iub
No support for HS-DSCH over Iur
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2728
Outline
HSDPA Principles HSDPA Channels and Bearers
– Power Setting of new channels
Capacity Management HS-DSCH Mobility Flow Control & Transport Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2729
Purpose of Iub flow control
Pre-buffer data in RBS to allow fast scheduling
Avoid buffer overflow or empty buffers in RBS
Keep an appropriate amount of data buffered in RBS– Conflicting requirements
Keep the RBS priority queues short in order to avoid excessive RLC RTT
Keep enough data in queue to ensure throughput when scheduled
Ensure that the flow is within Iub Transport Network limits
SDU buffer
RNC
RBS
UE
RBS buffer
HARQ buffer
TN
(Scheduler)
RLC buffer
Iub flow control
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2730
HSDPA enablers in the Transport
Iub solution optimized for efficient bandwidth utilization– With AAL2 Switching and UBR for HSDPA
New Best Effort AAL2 QoS class for handling HS traffic– Class C
AAL2 QoS separation between different traffic classes– A, B, C
User traffic Flow control for HSDPA
IMA for trunking gains– For >1.5Mbps HS bandwidth to a single user
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2731
Iub Configuration with AAL2 Switching, UBR, IMA
T1
T1
3 MbpsClass B:
DCH best effort
Class C: HSDPA best effort
Class A:Strict QoS
Voice, Video, CS64, Common Channels
R99 PS Data
AAL2/CBR
B
A
AAL2/UBRC
ET-MC1 / MC41
HSDPA Peak rate of up to 2.2Mb/s
Slide titleIn CAPITALS
50 pt
Slide subtitle 32 pt
Questions and Answers
Top right corner for field-mark, customer or partner logotypes. See Best practice for example.
Slide title 40 pt
Slide subtitle 24 pt
Text 24 pt
Bullets level 2-520 pt
Commercial in confidence HSDPA Overview 2005-09-2733