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Telecom Israel

Technical Tutorial

November 7th, 2006

University

Understanding HSPA

Understand HSPA:High-Speed Packet Access For UMTS

Understand HSPA:High-Speed Packet Access For UMTS

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 3

University

Understanding HSPA

About QUALCOMM University

QUALCOMM University (“QU”) offers the advanced technologytraining solutions you need to stay on the cutting edge of wirelesstechnology.

Visit the QU website for more information about individual training

products, international training centers, and distance learningopportunities, along with a complete list of classes—all developed byQUALCOMM, the pioneers of CDMA.

QUALCOMM University: www.qualcommuniversity.com

QUALCOMM: www.qualcomm.com



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 4

University

Understanding HSPA

Where Can I Learn More?

•WCDMA HSDPA: Protocolsand Physical Layer (1 day)

•WCDMA HSUPA: Protocolsand Physical Layer (1 day)

Want to learn more?

QUALCOMM University offers additional in-depth technical training related to this course.

To learn more about this or related topics, signup for the following courses.

To check out the schedules for these coursesand enroll, go to:

www.qualcommuniversity.com

Telecom Israel

Technical Tutorial

November 7th, 2006

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Understanding HSPA

UMTS Courses from QUALCOMM University

For the latest information on all QUALCOMM University courses, visit www.qualcommuniversity.com.



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 7

University

Understanding HSPA

Tutorial Objectives

¾Provide telecommunication professionals with the basicunderstanding of HSPA, the high speed packet accesstechnologies (HSDPA, HSUPA), and related applications,network architecture, and deployments.

¾The talk will present:

¾ the market drivers for UMTS HSPA

¾ the basic enabling techniques and terminology associatedwith HSPA

¾ the basic operations of HSPA

¾ the HSPA implementation and performances

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 8

University

Understanding HSPA

HSPA Motivations

Market Drivers



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 9

University

Understanding HSPA

Increasing Wireless Internet TrafficDemands Higher Data Rates

3G Enables Wider Options of Services

EducationEducation

FinancialFinancial

InformationInformation

BusinessBusiness

Aud io o n demandVideo on demand

Games on demand

Network Games

Reservation services

Database access

E-mail/Fax/Web

Location B ased Services

Emergency Call Locating

Safety Credit verification

Stock tradingWireless b anking

Financial news

Interactive shopping

E-commerce

Remote learning

Remote library access

Remote language laboratory

Workgroups

Remote LAN access

Videoconferencing

…and many

others

Entertainment

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 10

University

Understanding HSPA

CDMA2000 1xCDMA2000 1x

More Capacity, High Speed Data

Capacity/Quality

Roaming

Mobility

AMPS

TDMA

GSMPDC

cdmaOneIS-95A

cdmaOneIS-95B

cdmaOneIS-95B

Medium Speed Data

Multi-ModeMulti-Mode

Global Roaming

1G 2G 3G (IMT-2000)2.5G

Multi-BandMulti-Band

Multi-NetworkMulti-Network

GPRSGPRS

CDMA2000 1xEVCDMA2000 1xEV

WCDMAWCDMA

Time

IMT-2000 aims to achieve Anywhere, Anytime Communications

Key Features:•Commonality

•Compatibility

•High quality

•Small terminals

•Worldwide roaming

•Multimedia

•Wide range of services

3G (IMT-2000)



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 12

University

Understanding HSPA

GPRSGPRS

EDGEEDGE

WCDMA (R99)WCDMA (R99)

HSDPA/HSUPA

(Rel5 / Rel6)

HSDPA/HSUPA

(Rel5 / Rel6)

Peak Data Rate

S p e c t r a l E f f i c i e n c y

Rich Voice

Video Telephony

MM streaming

MM sharing

Wireless

Broadband Access

Interactive Gaming

VoIP with AMR-WB

Text Messaging Speech GSMGSM

Push-to-Talk

Customized

Infotainment

MultimediaMessaging

Data ServicesEvolution

E v o l v e d 3 G

Voice & Limi ted Data

Medium Speed Data

Voice & High Speed Data

3G Enables Advanced Data Services

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 13

University

Understanding HSPA

HSPA for Higher Speed

•Data Rate

– Demand for higher peakdata rates

•Delay

– Lower latency

•Capacity

– Better capacity and throughput

– Better spectrum efficiency– Finer resource granularity

•Coverage

– Better coverage for higher datarate

What are the requirements for HSPA?



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 14

University

Understanding HSPA

UMTS Data Rate Evolution

Uplink Peak Data Rate

(Typical Deploym ent)

Downli nk Peak Data Rate

(Typical Deploym ent)

GSM 9.6 kbps 9.6 kbps

GPRS 20 kbps 40 kbps

EDGE 60 kbps 120 kbpsWCDMA Release 99 64 kbps 384 kbps

HSDPA - Rele ase 5 384 kbps 10 Mbps*

HSUPA - Rele ase 6 1.4 Mbps (early dep loym ent) 10 Mbps

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 15

University

Understanding HSPA

Applications Benefiting from HSPA

Voice-over-IP (VoIP)

- Low latency, Quality of Service (QoS) control, fine resourcegranularity and improved capacity

Video Telephony (in Packet Switched domain)- Low latency, Quality of Service (QoS) control, high data rates

and improved coverage and capacity

Gaming

- Low latency, fast resource allocation

Video Share / Picture Share- High Uplink data rates and improved coverageand capacity

File Uploading (large files)- High Uplink data rates and improved coverage

and capacity

Delay

Sensitive

– Error

Tolerant

Delay

Tolerant

– Error

Sensitive



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 18

University

Understanding HSPA

Part I:UnderstandingHSDPA

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 19

University

Understanding HSPA

Review - UMTS Network Architecture

Core Network

User Equipment

UTRAN

MobileEquipment

USIM

Node

BNode

B

NodeB

RNC

RNC

HLR/ AuC

NodeB

NodeB

NodeB

GMSC PSTN/ISDN

SGSN GGSN Internet

MSC/VLR

NodeB

NodeB

Uu

Iucs

Iups

Iub

Iub

Iur



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 20

University

Understanding HSPA

Review - UMTS Protocol Stack

Mobility Management

(MM)

Radio Resources Control (RRC)

Supplementary

Services (SS)

Short Message

Services (SMS)

Layer 2

Physical Layer (L1)

Non-

Access

Stratum

Access

Stratum

GPRS Mobili ty

Management (GMM)

Session Management (SM)

Radio Link Contro l (RLC)

Medium Access Control (MAC)

Connection Management (CM)

Call Control

(CC)

Short Message

Services (SMS)

Circuit Switched Packet Switched

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 21

University

Understanding HSPA

Review - Release 99 Channels



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 22

University

Understanding HSPA

Review – RRC Modes and States

UTRAN Connected Mode

CELL_FACH

CELL_PCHURA_PCH

Idle Mode

(Camping on a UTRAN cell)

Channels: PCH, No Uplink

Mobility: URA Update

Calls: PS (no data transfer)

DRX Mode

CELL_DCH


Mobility: Cell Update

Calls: PS (no data transfer)

DRX Mode

Channels: FACH, RACH

Mobility: Cell Update

Calls: PS

Dedicated logical channels, but

common transport and physical

channels

No DRX Mode

Channels: Downlink DCH, Uplink

DCH

Mobility: Handover

Calls: PS, CS


Mobility: Loc ation/Routing Area Update

Calls: None, PS call might be in “ contextpreserved” state

DRX Mode

Establish RRCConnection

Release RRCConnection Establish RRC

Connection

Release RRCConnection

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 23

University

Understanding HSPA

Release 99 Principles

How is Packet Data Managed in Release 99?

• DCH (Dedicated Channel)– Spreading codes assigned per user

– Closed loop power control

– Macro diversity

• FACH (Common Channel)– Common spreading code

– Header defines user

– No closed loop power control

• DSCH (Downlink Shared Channel)– not implemented for FDD

– Common spreading code shared by many users

– User assignment by Physical Layer signaling

– Closed loop power control with DPCH



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 24

University

Understanding HSPA

DCH/FACH Comparison Summary

Mode DCH FACH

Channel Type Dedicated Common

Power Control

Closed Inner Loop

at 1500 Hz -

Slower Outer

Loop

None or slow

(based o n

measurement

report)

Soft Handover Supported Not Supported

Setup Time High Low

Suitabi l i ty for Bursty Data Poor Good

Data Rate Medium Low

Radio Performance Good Poor

How do we do Packet Data in Release 99

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 37

University

Understanding HSPA

What will HSDPA Address?

Release 99 Downlink Limitations

•Limited Peak Data Rate– Maximum implemented Downlink of 384 kbps

•Capacity and Throughput– Modulation and coding

QPSK

Convolution coding (R=1/2, 1/3) or turbo coding (R=1/3)

– Link adaptation due to channel conditions Fast closed inner loop power control, but

Slower outer loop

•Minimum TTI of 10 ms

•Slow Rate and Type Switching



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 38

University

Understanding HSPA

HSDPA Goals

9 Higher Data Rate

9 Higher User / Cell Throughput

9 Lower Latency

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 39

University

Understanding HSPA

HSDPA Enabling Technologies

How will HSDPA address the limitations of Release 99?

• Extension of DSCH

• Multi-Code operation

• Adapt ive modulat ion and cod ing

– QPSK and 16-QAM

– Coding from R=1/3 to R=1

– Fast feedback of channel condition

• Improve transmission efficiency

– Fast retransmission and Physical Layer HARQ

• Fast resource management

– Node B scheduling

• Reduce transmiss ion latency

– 2 ms TTI



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 40

University

Understanding HSPA

Common Channel for Data

Common Channel for data transfer using

the HS-PDSCH

H S - P D S C H

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 41

University

Understanding HSPA

Multi-Code Operation

• Fixed Spreading Factor SF=16– (Typical Spreading Factor for 128 kbps in Release 99)

• 1-15 codes can be reserved for HS-PDSCH

• Can be TDM or CDM between users

Up to 15 codes

reserved for

HS-PDSCHtransmission

User #1 User #2 User #3 User #4

2 ms (3 slots)



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 42

University

Understanding HSPA

Adaptive Modulation and Coding

• Coding from R=1/3 to R=1

• HSPDA supports 16-QAM modulation– 4 bits per symbol versus 2 bits per symbol with QPSK

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 43

University

Understanding HSPA

Link Adaptation versus Power Control

•Release 99– Use fast power control with

fixed data rate (DCH)

•HSDPA– Adapt the modulation and

coding to the link quality

Rat e #1 Rat e #2 Rat e #3 Rat e #2 Rat e #1 Rat e #2Rate #2

Switchinglevels

Channel

quality (C/I)Fast Link adaptation:

time

Rate #3: e.g. 16-QAM, R=3/4

Rate #2: e.g. QPSK, R=3/4

Rate #1: e.g. QPSK, R=1/2



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 44

University

Understanding HSPA

Scheduling Comparison

RNC

Node B

RELEASE 99SchedulingRLC ARQResource Allocation

RELEASE 5 (HSDPA)RLC ARQResource Allocation

RELEASE 5 (HSDPA)Scheduling

Link AdaptationHARQResource Allocation

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 45

University

Understanding HSPA

HSDPA Scheduling and Retransmissions

•Scheduling

– Done at the Node B

– No interaction with the RNC

– Based on channel quality feedback from the UE

•Retransmissions

– HARQ (link level retransmissions)– Done at the Node B

– Based on UE feedback (ACK/NACK)

– Soft combining at the UE



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 46

University

Understanding HSPA

Hybrid Automatic Repeat Request (HARQ)

•Scheme combining ARQ and Forward ErrorCorrection

•FEC decoding based on all unsuccessfultransmissions

•Stop-and-Wait (SAW) protocol

• Two basic schemes:

– Chase Combining

same data block is sent at each retransmission

– Incremental Redundancy (IR)

Additional Redundant Information sent at each retransmission

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 47

University

Understanding HSPA

HARQ – Illustration

N A K

N A K

A C K

P a s s

F a i l



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 48

University

Understanding HSPA

Comparison Summary

Mode DCH FACH HSDPA

Channel Type Dedicated Comm on Comm on

Power Control

Closed Inner Loop

at 1500 Hz - Slow

Outer Loop

None

Fixed Power

wi th l ink

adaptation

Soft Handover Supported Not Supported Not Supported

Sui tabi l i ty for Bursty Data Poor Good Good

Data Rate / Traffic Volum n Medium Low High

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 49

University

Understanding HSPA

UMTS Network Architecture with HSDPA

Core Network

User Equipment

UTRAN

MobileEquipment

USIM

Node

BNode

B

NodeB

RNC

RNC

HLR/ AuC

NodeB

NodeB

NodeB

GMSC PSTN/ISDN

SGSN GGSN Internet

MSC/VLR

NodeB

NodeB

UuIub

Iub

Iups

IucsHardware andSoftware Changes

Software Changes

Iur



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 50

University

Understanding HSPA

HSDPA Protocol Stack

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 51

University

Understanding HSPA

HSDPA Channels

New HSDPA Channels

Transport Channel

• High Speed Downlink Shared Channel (HS-DSCH)– Downlink Transport Channel

Physical Channels

• High Speed Shared Control Channel (HS-SCCH)– Downlink Control Channel

• High Speed Physical Downlink Shared Channel(HS-PDSCH)– Downlink Data Channel

• High Speed Dedicated Physical Control Channel(HS-DPCCH)– Uplink Control Channel



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 52

University

Understanding HSPA

HSDPA Channels (continued)

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 53

University

Understanding HSPA

HSDPA Operation Overview

1. Each UE reports channelquality on HS-DPCCH.

2. The Node B determineswhich and when each UE isto be served.

3. The Node B informs the UEto be served via HS-SCCH.

4. Then deliver the data to theUE via HS-DSCH.

5. The UE sends feedback(ACK/NAK) back to Node Bon HS-DPCCH.

HSDPA Operation

3dTower.emf

Node B

H S - D P C

C H

H S - D S C H

H S - S

C C H

P - C P I C H

UE

HS-DPCCH

HS-DSCH

HS-SCCH

P-CPICH



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 54

University

Understanding HSPA

HSDPA Channel Operation Timeline

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 55

University

Understanding HSPA

HS-PDSCH

High Speed Physical Downlink Shared Channel (HS-PDSCH)• Carries UE data

• Up to 15 HS-PDSCH may be assigned simultaneously

– UE capability indicates maximum number of codes it supports

• Uses Spreading Factor =16



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 56

University

Understanding HSPA

HS-DPCCH

High Speed Dedicated Physical Control Channel(HS-PDCCH)

• 1st slot carries ACK or NAK for received HS-DSCH blocks

• 2nd and 3rd slots carry Channel Quality Indicator (CQI)– UE measures Downlink CPICH channel quality

– CQI indicates the highest data rate for error rate <10%

– Frequency of CQI reports configured by UTRAN

• DTX during ACK/NAK and CQI slots if nothing to send

• Uses Spreading Factor = 256

HS-DPCCHUplink Channel

CQI

2 ms3 slots

ACK/

NAK

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 57

University

Understanding HSPA

HS-SCCH

High Speed Shared Control Channel (HS-SCCH)

• 1st part carries modulation information

– OVSF code assignment

– Modulation scheme

• 2nd part carries transport block size, Hybrid ARQ parameters

• UE Identity encoded over each part

– UE decodes each part independently

• UE assigned up to 4 HS-SCCHs to monitor

• Uses Spreading Factor =128



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 58

University

Understanding HSPA

Data Rate Example

Question:

Assuming a transport block size of 320 bits, what HSDPAdata rate can be achieved by a single UE using thechannel allocation timing shown above?

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 59

University

Understanding HSPA

Data Rate Example (cont.)

Answer:

320 bits are transmitted every 10 ms, so the maximumdata rate is 32 kbps.



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 60

University

Understanding HSPA

Theoretical HSDPA Maximum Data Rate

How do we get from 32 kbps to 14.4 Mbps?

•Multi-code transmission

•Consecutive assignments using multiple HybridAutomatic Repeat Request (HARQ) processes

•Lower coding gain

•16-QAM

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 61

University

Understanding HSPA

Multi-code Transmission

Data Rate with 15-code Multi-code

32 kbps X 15 =480 kbps



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 62

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Understanding HSPA

Consecutive Assignments

Data Rate with Consecutive Assignments

480 kbps X 5 =2.4 Mbps

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 63

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Understanding HSPA



• Each HSDPA assignment is handled by a HARQ process– HARQ Processes run in Node B and UE

– Up to 8 HARQ processes per UE

– Number configured by Node B when HSDPA operations begin

• The UE HARQ process is responsible for:– Attempting to decode the data

– Deciding whether to send ACK or NAK

– Soft-combining of retransmitted data

• The Node B HARQ process is responsible for:– Selecting the correct bits to send according to the selected retransmission

scheme and UE capability



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 64

University

Understanding HSPA

Lower Coding Gain

R=1/3 Turbo Coding and QPSK Modulation

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 65

University

Understanding HSPA

Lower Coding Gain (continued)

Data Rate with Rate 1 Turbo Coding and QPSK Modulation

2.4 Mbps X 3 =7.2 Mbps



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 66

University

Understanding HSPA

16-QAM

Data Rate with 16-QAM

7.2 Mbps X 2 =14.4 Mbps

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 67

University

Understanding HSPA

Theoretical HSDPA Maximum Data Rate

Review: How do we get to 14.4 Mbps?

• Multi-code transmission– Node B must allocate all 15 OVSF codes of length

16 to one UE

• Consecutive assignments– Node B must allocate all time slots to one UE

– UE must decode all transmissions correctly on the first transmission

• Lower Coding Gain– Effective code rate =1

– Requires very good channel conditions to decode

• 16-QAM– Requires very good channel conditions



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 69

University

Understanding HSPA

Inter-TTI Interval

Inter-TTI Interval = 2

HS-SCCH

HS-PDSCH 1

.

.

.

.

.

.HS-PDSCH N

HS-DPCCH

CQI

.

.

.

.

.

.

.

.

.

.

.

.

ACK ACK ACK

2 ms

1 2 3 4 5 6 7 8

Telecom Israel

Technical Tutorial

November 7th, 2006

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Understanding HSPA

Retransmissions

HS-SCCH

HS-PDSCH 1.

.

.

.

.

.

HS-PDSCH 15

HS-DPCCH

10 ms minimum retransmit interval

.

.

.

.

.

.

.

.

.

NAK ACK ACK ACK ACK ACK

.

.

.

.

.

.

.

.

.

ACK

1 2 3 4 5 6 7 8 9 10

2 ms

.

.

.

.

.

.

.

.

.



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Technical Tutorial

November 7th, 2006

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Understanding HSPA

ACK/NAK Repetitions

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 72

University

Understanding HSPA

Node B Implementation Considerations

Node B Considerations

•OVSF Code Allocation

•Power Allocation

•CQI Report Processing

•Scheduler

•HSDPA Cell Re-pointing Procedure

•Compressed Mode



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 73

University

Understanding HSPA

OVSF Allocation

S C C P C

H

H S - S C C

H

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 74

University

Understanding HSPA

Node B Transmit Power Allocation

T o t a l a v a i l a b l e c e l l p o w e r

T o t a l a v a i l a b l e c e l l p o w e

r



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 75

University

Understanding HSPA

CQI Report Processing

• UE measures CPICH strength

– Measurement reference period is 3 slots, ending 1 slot before CQI issent

• UE reports index into CQI Table

– Highest data rate for which UE can guarantee error rate <10%

• Node B may filter CQI reports

– Varying CQI means UE is in a fast changing environment

– Steady CQI means UE is in a stable environment

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 76

University

Understanding HSPA

Node B Scheduler

User #1 User #2User #3 User #4

HS -DSCH TTI

(3 slots = 2 ms)

User #1 User #2 User #2 Us er #3 User #1 User #4 User #4 User #2 User #1

User #1 User #2User #3 User #4

15 codes

reserved for

HS-PDSCH

transmission

Pure Time Division Mult iplexing

Combined Code and Time Division Multiplexing



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 77

University

Understanding HSPA

HSDPA Cell Re-pointing Procedure

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 79

University

Understanding HSPA

HSUPA Performance

Maximum Theoretical Data Rate:

• 14.4 Mbps

– 15 codes

– 16QAM

– Consecutive assignments (Inter-TTI spacing of 1)

– Coding Rate of 1

Practical Peak Data Rate:

• 10.0 Mbps

– Full capability UE

– Good RF conditions (High Cell Geometry)

– Single UE

• Dedicated HSDPA carrier



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 80

University

Understanding HSPA

Part II:UnderstandingHSUPA

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 81

University

Understanding HSPA

Release 99 Uplink Packet Data

How is Uplink Packet Data handled in Release 99?

• DCH (Dedicated Channel)

– Variable spreading factor

– Closed loop power control

– Macro diversity (soft handover)

• RACH (Common Channel)

– Common spreading code– Fixed (negotiated) spreading factor

– No closed loop power control

– No soft handover



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 82

University

Understanding HSPA

Release 99 Uplink Limitations

• Large Scheduling Delays

– Slow scheduling from RNC

• Large Latency

– Transmission Time Interval (TTI) durations of 10/20/40/80 ms

– RNC based retransmissions in case of errors

• Limited Uplink Data Rate

– Deployed peak data rate is 384 kbps

•Limited Uplink Cell Capacity

– Typically about 800 kbps

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 83

University

Understanding HSPA

High Speed Uplink Packet Access (HSUPA)

•Set of high speed channels is received at the Node B.

• Interference is shared by multiple users.

•Several users may be allowed to transmit at given data rateand power on a fast scheduling.



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 84

University

Understanding HSPA

Enhancements Provided by HSUPA

How wil l HSUPA address the limi tations of Release 99?

• Higher Peak Data Rate in Uplink

– Enable new services and improve user perception

• Improved Uplink Coverage for higher Data Rates

• Improved Uplink Cell Capacity

• Reduced Latency

• Fast Scheduling and Resource Control

– Increase resource utilization and efficiency

• Quality of Service (QoS) suppor t

– Improve QoS control and resource utilization

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 85

University

Understanding HSPA

How are Enhancements Achieved?

Improved CellCapacity

Higher PeakData Rates

ReducedLatency

Improved QoS

SupportFaster Resource

Control

Release 99 UL DCH HSUPA

Minimum TTIof 10 ms

Smaller TTIof 2 ms

Slow UL rateswitching

(RNC based)

Fast UL data ratecontrol in the Node B

Improved PhysicalLayer performance

through HARQ

Multiplexing of transportchannels at Physical Layer

Multiplexing of logicalchannels at MAC layer

Slow mechanism torequest resources

Fast mechanism torequest UL resources

Dedicated resource

allocation for latencysensitive applications

Dedicated resource

allocation that couldnot be used efficiently

New TransportChannel

New PhysicalChannels



Telecom Israel

Technical Tutorial

November 7th, 2006

Page 86

University

Understanding HSPA

HSUPA vs. HSDPA

HARQ with Fast Retransmission at Layer 1

Fast Node-B Scheduler

“ Many-to-One”

Rise-over-Thermal (RoT)

Fast Node-B Scheduler

“ One-to-Many”

Shared Node-B Power and Code

Fast Power Contro l

Soft Handover

Rate/Modulation Adaptation

Single Serving Cell

Dedicated Channel wi th

Enhanced Capabilities

New high-speed Shared

Channel

HSUPAHSDPA

Telecom Israel

Technical Tutorial

November 7th, 2006

Page 87

University

Understanding HSPA

Rise-over-Thermal Noise

Determination of

grant for the UE

(At NodeB)

NodeB

UL Interference Level

(RoT measure)

UE Data Rate

Interference from

other UEs

Grant Received

from NodeB

UE Transmit

Power

2

3

1

5

4

In order to decode received data correctly, aminimum SINR shall be guaranteed at theNode B receiver.

Rise-over-Thermal is a measure of the

Uplink load.

1. By increasing the number of transmitting UEsand their transmit power, the level of interference in the Uplink band increases.

2. This interference is perceived by theNode B receiver as noise, affecting the SINR.

3. The Node B controls the interference level byadjusting the UE grant assignments.

4. When the UE receives a new grant, it uses it incombination with available UE transmit powerand the amount of data in the buffer…

5. …to determine the data rate and thecorresponding transmit power.



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Understanding HSPA

Node B Scheduler for HSUPA

The HSUPA scheduler addresses the trade-off between:

Several users

that want to

transmit at

high data rate

all the time

3dTower.emf

Node B

Satisfying all

requested grants

while preventing

overloading and

maximizing

resource utilization

and

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Technical Tutorial

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Understanding HSPA

Rise-over-Thermal Loading

load

RoTOverload

margin

Target Load

Possible additional load with HSUPA

R99 UL

R6 UL

With the introduction of HSUPA, a lower Uplink margin for preventing overload situations can be used, thanks to the fastresource allocation and contro l mechanisms in the Node B.



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November 7th, 2006

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Understanding HSPA

HSUPA Channel Operation

1. The UE sends a Transmission

Request to the Node B for gettingresources.

2. The Node B responds to the UE witha Grant Assignment, allocatingUplink band to the UE.

3. The UE uses the grant to select theappropriate transport format for theData Transmiss ion to the Node B.

4. The Node B attempts to decode the

received data and send ACK/NAK tothe UE. In case of NAK, data may beretransmitted.

3dTower.emf

Node B

R E Q

G R A N T

D A T A

A C K / N A K

UE

HSUPA Operation

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Understanding HSPA

HSUPA Channel Operation (continued)

1. Transmission Request

The UE requests data

transmission by means of theScheduling Information (SI),which is determined according

the UE Power and Buffer Dataavailability.

The scheduling information issent in-band to the Node B.



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Understanding HSPA


2. Grant Assignment

The Node B determines the

UE Grant by monitoringUplink interference (RoT at

the receiver), and byconsidering the UEtransmission requests and

level of satisfaction.

The grant is signaled to the

UE by new grant channels.

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Understanding HSPA


3. Data Transmission

The UE uses the received

grant and, based on its powerand data availability, selects

the E-DCH Transport Format

and the correspondingTransmit Power .

Data are transmitted by the UEon together with the related

control information.



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Understanding HSPA


4. Data Acknowledgment The Node B attempts to

decode the received dataand indicates to the UE with

ACK/NAK if successful.

If no ACK is received by the

UE, the data may beretransmitted.

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Understanding HSPA

UMTS Network Architecture with HSUPA

Core Network

User

Equipment

UTRAN

Mobile

EquipmentUSIM

Node

BNode

B

Node

B

RNC

RNC

HLR/

AuC

Node

B

Node

B

Node

B

GMSCPSTN/ISDN

SGSN GGSN Internet

MSC/VLR

Node

B

Node

B

UuIub

Iub

Iups

IucsHardware andSoftware Changes

Software Changes

Iur



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Understanding HSPA

HSUPA Protocol Stack

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Understanding HSPA

HSUPA Uplink Channels

New HSUPA Uplink Channels:

•Enhanced Uplink Dedicated Channel (E-DCH)

– Uplink Transport Channel

•E-DCH Dedicated Physical Data Channel(E-DPDCH)

– Uplink Physical Channel

•E-DCH Dedicated Physical Control Channel(E-DPCCH)

– Uplink Control Channel



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Understanding HSPA

HSUPA Downlink Channels

New HSUPA Downlink Channels:•E-DCH Hybrid ARQ Indicator Channel (E-HICH)

– Downlink Physical Channel

•E-DCH Absolute Grant Channel (E-AGCH)


•E-DCH Relative Grant Channel (E-RGCH)


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Understanding HSPA

HSUPA Channel Mapping

Rel. 99

Rel. 5

Rel. 6



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Understanding HSPA

Uplink Channels

E-DPDCH

•Carries the payload.

•May include a schedulingrequest from UE to Node B.

E-DPCCH

•Carries control informationrequired to decode thepayload carried by E-DPDCH.

•Carries an indication fromUE to indicate to the Node B

whether the assignedresources are adequate.

SI

TTI

PAYLOADHD

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Understanding HSPA

Downlink Channels

E-AGCH

• The absolute grant carries maximumallowed E-DPDCH/DPCCH ratio.

• Carries information that controls HARQprocess.

E-RGCH

• The relative grant carries a simplecommand to increase (UP), Decrease(DOWN), or keep (HOLD) the current

grant.

E-HICH

• Gives feedback to the UE about previousdata transmission, carrying Acknowledge(ACK) or Not Acknowledge (NAK).

Up / Down / Hold

TTI

ACK/NAK

TTI



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Understanding HSPA

HSUPA Channel Timing

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Understanding HSPA

HSUPA Features (continued)

•Shorter TTI of 2 ms

– In HSUPA both 10 ms and 2 ms TTI are supported

– A shorter TTI allows reduction of the latency and increasingthe average and peak cell throughput

– A tighter resource control can be implemented, thus allowingfor additional capacity

•Higher Peak Data Rate

– For a 10-ms TTI UE, peak data rate is limited to 2 Mbps

– Higher peak data rates can be achieved with a 2-ms TTI UE

– 5.76 Mbps is the maximum peak data rate for HSUPA



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Understanding HSPA


•Hybrid-ARQ– N-channel Stop-and-Wait

(SAW) protocol, with4 processes for 10 ms TTIand 8 processes for 2 ms TTI

– Synchronousretransmission

– Separate HARQ feedbackis provided per Radio-Link

3dTower.emf

Node B

3dTower.emf

Node B

D A T A

D A T A

N A K

A C K

E-DCH cells partof the Activ e Set

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Understanding HSPA


Rate Request

• The UE requests grant for data transmission

Rate Control

• The UTRAN controls the grants for transmission on Uplink

– Scheduled transmissions granted by the Node B for high speed data

– Non-Scheduled transmissions granted by the RNC for delay-sensitiveapplications

Load Control

• The UTRAN monitors Rise-over-Thermal (RoT) noise at theNode B receiver.

– UTRAN prevents overloading by reducing scheduled grants to UEs



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Understanding HSPA


HSUPA Quali ty of Service (QoS)• QoS is linked to a logical channel.

• Up to 15 logical channels can be

mul tiplexed on a single MAC-e PDU.

– Each logical channel may have a differentQOS and a different priority level.

• Priority level is considered while

forming a MAC-e PDU.

• Parameters affecting HSUPA

performance are set as per the QoS

requirements.

Air interface

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Understanding HSPA

E-DCH Active Set and Mobility Support

3dTower.emf

Node B

3dTower.emf

Node B

3dTower.emf

Node B

Serving E-DCH RadioLink Set (RLS)

Serving

E-DCH cellNon-Serving

Radio Links (RL)

Example with an Act ive Set of 4 cell s

There are three different typ es of

Radio L inks in the UE Active Set:

• Serving E-DCH Cell – The cell fromwhich UE receives AGCH fromscheduler.

• Serving (E-DCH) RLS – Set of cellsthat contain at least the serving celland from which theUE can receive and combine theserving RGCH.

• Non-Serving RL – Cell that belongsto the E-DCH Active Set but does notbelong to the serving RLS and fromwhich the UE can receive a RGCH.



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Understanding HSPA

HSUPA Serving Cell Change

From the 3GPP Standards:

HSUPA Serving Cell is the same as HSDPA Serving Cell

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Understanding HSPA

Active Set Composition with HSUPA

E-DCHServing Cell

ServingRL

ServingRL

Serving RLS

…

Non-Serving RL

Non-Serving RL

…

E-DCH Active Set (max 4 cells) Other AS cel l

Other AS cel l

…

DPCH Active Set (max 6 cells)

Send AGCH

UE can combine RGCHcommands from these cells

Send non-serving RGCH Is in SHO

All cells belongingto the UE AS

All cells belongingto the UE AS that

handle E-DCH



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Understanding HSPA

Theoretical HSUPA Maximum Data Rate

How do we get 5.76 Mbps?

• Lower Coding Gain

– Effective code rate =1

– Requires very good channel conditions to decode

• Lower Spreading factor

– UE can use SF2

• Multi-code transmission

– UE can use up to 4 codes, 2 with SF4 plus 2 with SF2

– Require some power back-off at UE side

• Shorter TTI

– Requires higher processing capabilities at terminal and Node B

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Understanding HSPA

E-DPDCH with SF4 and Puncturing

Maximum payload for spreading factor o f 4, TTI of 2 ms and coding

rate of 1 is 1920 bits (for 960 kpbs).



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Understanding HSPA

Lower Spreading Factor SF2

Maximum payload for spreading factor of 4, TTI of 2 ms and coding

rate of 1 is 3840 bits (for 1920 kpbs).

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Understanding HSPA

Multi-code Transmission

Use of mult i-code transmission 2 x SF2 + 2 x SF4

(2 x 1920 kbps) +(2 x 960 kbps) =5760 kbps



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Understanding HSPA

HSUPA UE Capabilities

2000 kbps

2000 kbps

2000 kbps

1448 kbps

1448 kbps

711 kbps

Peak rate for TTI = 10 ms*

5742 kbps

--

2886 kbps

--

1448 kbps

--

Peak rate for TTI = 2 ms

Category 6

Category 5

Category 4

Category 3

Category 2

Category 1

E-DCHCategory

4

2

2

2

2

1

Max number of E-DPDCHchannels

SF2 + SF 4

SF2

SF 2

SF 4

SF 4

SF 4

MinimumSF

2 & 10 ms

10 ms

2 & 10 ms

10 ms

2 & 10 ms

10 ms

SupportedTTI

* Maximum Peak data rate for 10 ms E-DCH TTI operation is 2 Mbps in all configurations

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