latest trends and new enhancements in 3g wireless communications rao yallapragada senior director,...

Latest Trends and New Enhancements in 3G Wireless Communications

Rao YallapragadaSenior Director, Qualcomm Inc.April 12, 2004

Latest Trends and New EnhancementsApril 2004

2

Presentation Outline

• 3G Reported Subscribers

• 3G CDMA Evolution

• Voice and Data Capacity Evolution of 3G Technologies

• New Enhancements in 3G Technologies

– CDMA2000 1x

– CDMA2000 1xEV-DO

– WCDMA

• Summary

3G Wireless Subscriber Growth


4

3G CDMA Reported* Subscribers3G CDMA Reported* Subscribers(As of March 30, 2004)(As of March 30, 2004)

05

10152025303540455055606570758085

Mar Apr May June July Aug Sep Oct Nov Dec Jan Feb Mar

Su

bscri

bers

(M

)

88.2 million

6.46 million

4.31 million

Source: www.3Gtoday.com


5

Worldwide CDMA Subscriber Evolution Forecast

0

100

200

300

400

500

600

700

800

2000 2001 2002 2003 2004 2005 2006 2007 2008

2G CDMA 3G CDMA 3G WCDMA

Future(Millions)

Source: Strategy Analytics, April 2003 and www.3gtoday as of December 2003, CDG September 2003

3G CDMA is Well Established & GrowingNow in Use in Two Flavors: CDMA2000® and WCDMA

Over 98M Subscribers, 75 Operators, 37 Countries, 430 Handsets, 43 Vendors

September >174M subs

http://www.3gtoday/


6

Operators Expanding Data Services With CDMA2000 1xEV-DO 5 Commercial Operators

Over 5M EV-DO subscribers as of January 2004

Over $1 billion EV-DO national rollout over next 2 years

655065005500 6800

Coming Soon

Pelephone

(PT Mobile-8)

(Telecsa Ecuador)

2.4 MbpsgpsOneARM 7

2.4 MbpsgpsOneARM 9

2.4 MbpsHigher resolution

video/graphicsCamera to 4 megapixel

3.1MbpsCamera to 4 megapixel

Launched November 2003


7

Latest Trends and Driving Factors

• High Intensity Multi-Media Capabilities– More efficiency in multi-media content

delivery

• Enhancements to support Quality of Service

• Efficient and flexible Packet based Video Telephony

• Support for VoIP and Low-latency applications, e.g., Gaming applications

• Instant Multi Media (IMM)

• Broadcast and Multicast services

• High Speed Data on both Up and Down Links

65005500

“Push to See”

Samsung SCH V310

3G CDMA Evolution


9200620052004200320022001200019991995 200620052004200320022001200019991995

In -Band Migration and

Designed for In-Band Migration and New Spectrum

3G CDMA

2G CDMA

3G CDMA Evolution

1.25 MHzVoice & Data

2.5G CDMA

Rel. 4

HSDPA

Additional voice capacity doubling

- Terminal antenna diversity

Rel. 5

CDMA2000 1X

14.4 kbps dataSoft HandoffSynchronous Timing

64 kbps packet data

− Channel Concatenation

Double voice capacity− Fast Fwd Power Control− Coherent Uplink 153.6 kbps packet data− Turbo Codes

307 kbps packet data

Simultaneous voice and data

Dedicated & OptimizedFor Packet Data2.4 Mbps Peak Rates All IP Architecture

Improvementsto data services.

More flexible data packet scheduling.

64/384 kbps cs/packet dataSoft handoffAsynchronous timing

Improvements to data services

More flexible datapacket scheduling

cdmaOne

QoS, Broadcast, Personal Media, IMM ,2x

1xEV-DV

Forward Link: Peak Rate: 3.1 mbps

Reverse Link: Peak Rate:1.8 mbps

Fwd & Rev. Capacity Gains

Forward Link: Peak Rate 3.1 mbps

Reverse Link: Peak Rate 1.8 mbps

EUL

Rel. 6

EnhancedUp-Link

IS - 95A IS-95B

1.25 MHzOptimized for Data

IS-2000 Rel. 0 Rel. A Rel. B Rel. C Rel. D

Designed for New Spectrum

5 MHzVoice & Data

3GPP Rel. 99

CDMA2000 1xEV-DO

UMTS(WCDMA)

IS-856, Rel. 0 Enhancements Rel. A


10

Voice Capacity Evolution of 3G Technologies


11

Data Capacity Evolution of 3G Technologies

New Enhancements in 3G Wireless Technologies


13

CDMA2000 Standards Status

IS-95A/B

1xRelease 0

1x/3xRelease A

1x/3x Release B

1xEV-DO Revision 0

1xRevision C(1xEV-DV FL)

Arrow denotes evolution of standard, maintaining backward compatibility

cdma2000 family

Done

Done Done Done Done

1xRevision D(1xEV-DV RL)

Done

1xEV-DO Revision A

Publish Date: March 2004

Publish Date: March 2004


14

CDMA2000 1X Enhancements

• Capacity Enhancements via Mobile Receive Diversity and SMV Vocoders

• Release C Enhancements

– Introduces 1xEV-DV and a new data mode for the forward link

– New Forward Packet Data Channel (F-PDCH)

• High data rate, rapidly time-shared among users

• Dynamic modulation and coding based on channel condition

• Forward Link Data Rates up to 3.1 Mbps


15

CDMA2000 Release D Enhancements

• Simultaneous wireless voice and bi-directional high speed data on a single RF carrier

• Reverse Link Enhancements

– Hybrid ARQ

• Re-transmit & combine, similar to 1xEV-DV FL

• Synchronous re-transmissions

– MAC-layer control of data transmissions

– Higher peak data rates: ~ 1.8 Mbit/s

– Fast scheduling with shorter variable duration frames

– Base station supervised rate control

– Adaptive Modulation and Coding (AMC)

• Fast Call Setup

• Backward compatible with IS-95 and CDMA2000 Releases 0, A, B & C

• Expected Date of Commercial Deployments: Y2005


16

Throughput gains with proposed enhancements

Average Thput [kbps]

0.00

50.00

100.00

150.00

200.00

250.00

300.00

350.00

400.00

450.00

500.00

20ms - 1Transmission 10ms - 2Transmissions 10ms - 3Transmissinons 5ms - 4Transmissions

(~1x Revision C)1x Revision D

candidates

Full Buffer RL Throughput

RL

Th

rou

gh

pu

t(k

bit

/s p

er s

ecto

r)

1xEV-DV: Overview


18

Introduction to 1xEV-DV

• CDMA2000 1x FL currently has 3 modes of transmitting data:

– Fundicated Channel (F-FCH / F-DCCH)• Low rate data, circuit-switched like• One to each MS

– Supplemental Channel (F-SCH)• Higher rate data, packet data or circuit-switched• Typically time-shared among users, ~160 ms at a time

– Broadcast Control Channel (F-BCCH)• Small payloads, low rate, large latencies• SMS-like data

• Introduces a new Packet Data Channel (F-PDCH) :– Called as FL Radio Configuration 10

– High rate, rapidly time-shared among users

– Uses adaptive modulation and coding schemes

E


19

CDMA2000 Compatibility

• CDMA2000 Revision C is fully backward compatible:– IS-95A or newer mobile stations can operate in a Revision C cell– 1xEV-DV capable mobiles can do data on older systems

Mobile Station supporting Revision C

Base Base Station Station

supporting supporting Revision CRevision C

F-PDCH

Base Base Station Station

supporting supporting Revision 0Revision 0

F-SCH



F-PDCH

E


20

1xEV-DV: Key Concepts

• Maximizes the use of Forward Link resources – Forward Transmit power and – Code channel Resources

• Allocates left-over power to the packet data channel (PDCH)

• Data to different users are TDM’d on F-PDCH

• Uses advanced communication techniques:– Channel-sensitive scheduling – Multi-user diversity– Adaptive modulation and coding– Incremental redundancy


21

1xEV-DV Dynamic Resource Allocation

1xEV-DV BTS

Transmit Power

Time

Maximum

Fundamental Channels

Overhead Channels

Packet Data Channel

– Pool unused power and code channels into F-PDCH

– Transmission must adapt to dynamics in resources

1x BTS Transmit

Power

Time

Maximum

Supplemental Channel(s)

Fundamental Channels

Overhead Channels

Walsh Space

Time

Leftovers pooled into PDCHDedicated & Common CHs


22

F-PDCH Time-Sharing

BTS Transmit

Power

Time

Maximum

For User 1

Fundamental and

Supplemental Channels

Overhead Channels

For User 2

E


23

4 Key Principles of 1xEV-DV

1) Rapid Adaptive modulation and coding for each transmission

2) Transmit for short durations of time

Adapt parameters based on:a. Available BTS resourcesb. Amount of data to transmitc. Channel condition

Allows the full use of available resources

Transmission durations of 1.25 ms to 5 ms:Minimizes variations during transmission period due to:

a. Available resourcesb. Channel conditions

E


24

4 Key Principles of 1xEV-DV

3) Transmit to only 1 (or 2) users at a time

Wait, and transmit to a user when the user’s channel is at its bestAvoids wasting power trying to get a packet through the channel when it has faded away

Also called as Adaptive Asynchronous Incremental Redundancy techniqueGet ACK or NAK back fast from the MSCombine transmissions and re-transmissions for better decodingAllows to be very aggressive and transmit at highest data rate possible

4) Provide a method for fast and efficient re-transmission

E

1xEV-DO: New Enhancements Revision A


27

What’s Next for CDMA2000 1xEV-DO?Multimedia Services, Increase Data Rates and System Capacity, and Lower Costs

Personal MediaMultiple channels

of video/audio

Instant Multi-mediaAudio and video together

Quality of Service (QOS)Different levels of

priority

Location-based services (LBS)

High resolution locations

2x MulticarrierTwo 1xEV-DO carriers

simultaneously, doubling data rates

Equalizer Increase sector capacity 20-60%

Receive Diversity4X capacity in 1.25 MHz


28

1xEV-DO Release A Enhancements

• Capacity Improvement relative to existing 1xEV-DO systems

– Higher Data Rates on both Forward and Reverse Links

– Better utilization of PL throughput with improved RL MAC algorithms

• QOS Support with improved Latency Characteristics– Low, Bounded Latency for CBR applications (VoIP, Gaming etc.)

– Low, Transient Latency for sporadic, interactive traffic (Telnet etc.)

• Similar link budget as the current system

• Backward compatibility and Interoperability with legacy DO systems


29

Physical and MAC Layer Features

• Reverse Link

– Physical Layer Hybrid ARQ: “CDMA with Hybrid ARQ”

– Flexible Packet Length

– Higher Peak Rate (153.6 kbps 1.8 Mbps)

– Finer Rate Quantization

– Enhanced MAC Algorithms

– Improved Latency Performance and Better QoS Support

• Forward Link

– Improved Packing Efficiency

– Higher Peak Rate (2.4 Mbps 3.1 Mbps)

– Improved QoS Support


31

Physical Layer ARQ Timeline

ACK PCNAK P

CACK PCNAK P

C NAK PCACK P

CNAK PCNAK P

C

Pkt 0 Pkt 1 Pkt 2 Pkt 3 Pkt 1' Pkt 1''Pkt 4 Pkt 3'

Interlace Period12 slots

(RL Subframe)4 slots

4 slots 1 slot FL ARQ Channel

RL Sub-Packets

(Three) Packet Intelaces

3 slots

Power Control Slots


32

Key Factors to Better Performance

• Capacity Improvement

– Higher Data Rates and Finer Quantization

• Data rates ranging from 4.8 kbps to 1.8 Mbps

• Smoother rate transitions and interference variation

– Improved code rates and higher order modulation for large packets

• QPSK modulation introduced

• Data channel spreading uses either or both of 2-ary and 4-ary Walsh code channel

• Code rate 1/5 for all 16-slot packets

– Hybrid ARQ with IR

• Enables packet to early terminate in the presence of channel variation and imperfect power control


33

Key Factors to Better Performance

• Latency Improvement

– Ability to start a new packet at 4-slot boundaries

– Terminals have the ability to boost transmit power to force packet termination after the first, second or third sub packets

• The power boost procedure is regulated by RL MAC

• Flexibility in the choice of Payload Size Vs. Data Rate combinations

– Bigger/Longer Packets provide more coding gain, time diversity, and are more capacity-efficient

– Smaller/Shorter Packets provide better packing efficiency (for low rate traffic) and are more delay-efficient


34

Throughput & Latency Results

CDMA RL without ARQ and 600 Hz PC) 8-slot ARQ [ 2 subpackets ] with 200Hz PC

Chan. Num Sect Cap AvgROT Latency Chan. Num Sect Cap AvgROT 4-sl ET LatencyModel AT kbps dB ms Model AT kbps dB % ms

A 16 404 5.3 40.0 3 km/h A 12 459 5.7 84.4 13.1B 16 351 5.4 40.0 10 km.h B 12 414 5.6 71.9 15.6C 16 350 5.3 40.0 30 km/h C 12 415 5.6 74.4 15.1D 16 396 5.2 40.0 120 km/h D 12 465 5.2 71.6 15.7E 16 505 5.2 40.0 Rician E 12 589 5.2 49.3 20.1A 8 403 4.5 40.0 3 km/h A 8 460 5.1 83.6 13.3B 8 361 4.7 40.0 10 km.h B 8 415 5.1 72.3 15.5C 8 358 4.6 40.0 30 km/h C 8 412 5.0 73.7 15.3D 8 394 4.5 40.0 120 km/h D 8 448 4.9 68.0 16.4E 8 487 4.6 40.0 Rician E 8 550 4.8 47.5 20.5

16-slot ARQ [ 4 subpackets ] with 200Hz PC

Chan. NumAT Sect Cap AvgROT 4-sl ET 8-sl ET 12-sl ET LatencyModel 200Hz kbps dB % % % ms

3 km/h A 16 613 5.7 12.3 62.6 90.9 36.8 10 km.h B 16 590 6.1 10.7 53.4 89.7 39.3 30 km/h C 16 571 6.2 16.6 63.7 91.7 35.6 120 km/h D 16 593 5.5 11.2 59.4 90.7 37.8 Rician E 16 707 5.5 0.6 32.1 85.8 46.3 3 km/h A 8 615 4.8 7.6 61.5 90.3 38.1 10 km.h B 8 595 4.8 8.0 51.9 88.5 40.3 30 km/h C 8 577 4.8 11.1 59.8 91.0 37.6 120 km/h D 8 587 4.7 6.2 55.6 90.5 39.5 Rician E 8 689 4.8 0.2 30.6 85.8 46.7


35

Performance Evaluation

• Preliminary simulation results show

– Near 50% improvement in capacity over Rev. 0 with similar latency performance

• 10 AT/sector ~ Capacity = 600 kbps

– Over 60% improvement in latency reduction over Rev. 0 with similar capacity performance

• Tradeoff between capacity and latency tradeoff

– Use bigger and longer packets for higher capacity

– Use smaller and shorter packets to achieve lower latency

New Enhancements in WCDMA Technologies


37

31

6

9

2003 Est. 2004 Est.ROW Europe

3G WCDMA is Here Today

QUALCOMM WCDMA Handset EstimateAs of January 21, 2004

2M subs in Japan Jan 2004, FOMA coverage area from 98% to 99% by the end of

FY03

4M

15M

Source: DoCoMo Q3’03 Earnings


38

WCDMA Enhancements

• Release 4 Enhancements

– All-IP Core Network

– Efficient IP support

– Expected Date of Commercial Deployments: Y2004


– High Speed Packet Data Channel (HSPDA)

• Peak Data Rates: 14.4 Mbps

• Average Sector Throughput: 2.2 to 4.2 Mbps in 5 MHz spectrum

• Modulation Schemes: QPSK & 16-QAM

• Expected Date of Commercial Deployments: Y2005


– Enhanced Uplink (EUL)

WCDMA HSDPA: Overview Release 5


40

HSDPA Features

• Overlay on top of regular R’99 W-CDMA Channels

• New Forward Link Data Channel similar to EV-DV

• Hybrid ARQ– Incremental Redundancy – Soft Combining– Modulation Rearrangement– Fast Re-transmissions

• Adaptive Modulation and Coding– Channel sensitive scheduling

• Based on Channel Quality Information feedback

– Adaptive/Asynchronous re-transmissions– Higher order modulation (QPSK & 16QAM)


41

Features (cont.)

• CDM to be able to schedule multiple users in parallel

• Mobility achieved through higher layer signaling

• Associated Dedicated Channel– Maximum spreading factor SF256– Used to transmit higher layer signaling

• Multiple UE capabilities– Modulation (support for 16QAM)– Number of codes– Inter-TTI time (Nb of HARQ processes)


42

Deployment Aspects

• Higher data-rates through the back-bone– 10Mbps peak rate

– 2Mbps average rate

• More complex Node-B– Protocol termination

– Scheduling/Rate selection

• UE Capabilities– Support of different UE classes

– Varying performance / complexity / costs

– 12 different classes• From 900kbps-14.4Mbps peak rate

• Support for 16QAM

• Support for 5/10/15 SF16 Codes


43

HSDPA Performance

• Theoretical limit– 14.4Mbps (3840kcps*15/16*4)

– Essentially impossible to obtain in the field

• Practical limit– 10Mbps (3840kcps*15/16*4*3/4)

– A single active UE in the network

– Highest capabilities

– Very close to the BTS

• Average data-rate based on simulations– 2.5Mbps for full capability UEs

– 2Mbps for limited capability UEs (5/15 codes, no 16QAM)

WCDMA EUL: Overview Release 6


45

WCDMA Enhancements


– Enhanced Uplink (EUL)

• Increased average cell throughput

• Peak Data Rates: 4 Mbps

• Uses adaptive Modulation Schemes

• Uses QPSK Modulation

• Hybrid-ARQ Protocols

• EUL will be strictly scheduled

– Multimedia Broadcast Multicast Systems (MBMS)

– MIMO Techniques and Beam forming Enhancements

– Expected Data of Completion of Standards: Dec 2004

– Expected Date of Commercial Deployments: Y2006


46

EUL Design Goals

• Increase average cell throughput– Peak throughput is not a major driving factor

• Node-B scheduling– Reduced turn-around time

• Improved link efficiency– Boosted phase reference– Retransmissions with IR


47

EUL Baseline Design Proposal

• Node-B Scheduled system• TTI = 2 ms or 10 ms

– UE allowed to use only one TTI– Typical mapping based on UE SHO status

• Modulation– QPSK

• SF = 4– Maximum number of OVSF codes = 3

• HARQ– Synchronous operation

• Retransmissions– 4 redundancy versions– Incremental redundancy (IR)

• Peak Rate– 4.096 Mbps with 2 ms TTI– 819.2 kbps with 10 ms TTI


49

Summary• 3G wireless services are rapidly spreading the global market place with

CDMA as the preferred technology solution

• The following are the key 3G Technologies that have emerged to be the key commercial players:

– CDMA2000 1X

– CDMA2000 1xEV-DO

– WCDMA

• The main focus of 3G so far has been to provide high capacity voice and higher downlink data throughput

– 26 Erlangs in 1.25 MHz voice capacity with CDMA2000 1x

– 1.15 Mbps in 1.25 MHz downlink average sector throughput with 1xEV-DO

– 51 Erlangs in 5 MHz voice capacity with WCDMA

• A host of new enhancements are underway for all flavors of 3G CDMA technologies

– More Capable Uplink

– Provision for higher data rates for both Up and Down links

– All IP, QoS and Support for Multimedia applications

– 3.1 Mbps in 1.25 MHz carrier Downlink Peak Data Rates with 1xEV-DO

– 4.1 Mbps in 5 MHz carrier Uplink Peak Data Rates with WCDMA/HSDPA

– 52 Erlangs Voice Capacity in 1.25 MHz carrier with CDMA2000

Thank You


51

1xEV-DV: Data and Voice Performance Issues

• Optimal data solution is possible when packet data is sent on a dedicated RF channel where data throughput can be maximized by using the following techniques:

– Transmit full power and use all code channels whenever data is to be transmitted

– Apply multi-user diversity with channel-sensitive scheduling– Use Adaptive modulation and coding– Use Incremental redundancy (H-ARQ)

• BS transmit power and number of code channels in use vary rapidly because of fast forward power control and soft handoffs of voice users

• Requires reserving margin in both power and code channels for voice traffic

• Power may not be available for an optimal data solution– Not able to transmit at high data rates even if channel condition is good

• Results in loss in data throughput without gaining in voice capacity A net loss in efficiency


52

RL Packet Parameters (1)

Payload Size (bits)

Modu-lation

Effective Data Rate (kbps) Code Rate [ Repetition ]

After 4 slots

After 8 slots

After 12

slots

After 16

slots

After 4 slots

After 8 slots

After 12

slots

After 16

slots

[1] 128 BPSKD0

19.2 9.6 6.4 4.8 1/5 [ 3.2 ]

1/5 [ 6.4 ]

1/5 [ 9.6]

1/5 [ 12.8]

[2] 256 BPSKD0

38.4 19.2 12.8 9.6 1/5 [ 1.6 ]

1/5 [ 3.2 ]

1/5 [ 4.8 ]

1/5 [ 6.4]

[3] 512 BPSKD0

76.8 38.4 25.6 19.2 1/4 [ 1 ]

1/5 [1.6]

1/5 [2.4]

1/5 [3.2]

[4] 768 BPSKD0

115.2 57.6 38.4 28.8 3/8 [ 1 ]

1/5 [1.07]

1/5 [ 1.6]

1/5 [ 2.13]

[5] 1024 BPSKD0

153.6 76.8 51.2 38.4 1/2 [ 1]

1/4 [ 1 ]

1/5 [ 1.2]

1/5 [1.6]


53

RL Packet Parameters (2)

Payload (bits)

Modu-lation

Effective Data Rate in kbps Code Rate [ Repetition ]

After 4 slots

After 8

slots

After 12

slots

After 16

slots

After 4 slots

After 8

slots

After 12

slots

After 16

slots

[6] 1536 QPSKD0

230.4 115.2 76.8 57.6 3/8 [ 1 ]

1/5 [1.07]

1/5 [ 1.6]

1/5 [ 2.13]

[7] 2048 QPSK D0

307.2 153.6 102.4 76.8 1/2 [ 1 ]

1/4 [ 1 ]

1/5 [ 1.2]

1/5 [1.6]

[8] 3072 QPSKD1

460.8 230.4 153.6 115.2 3/8 [ 1 ]

1/5 [1.07]

1/5 [1.6]

1/5 [2.13]

[9] 4096 QPSK D1

614.4 307.2 204.8 153.6 1/2 [ 1 ]

1/4 [ 1 ]

1/5 [ 1.2]

1/5 [1.6]

[10] 6144

QPSKD0 & D1

921.6 460.4 307.2 230.4 1/2 [ 1 ]

1/4 [ 1 ]

1/5 [ 1.2]

1/5 [1.6]

[11] 8192

QPSKD0 & D1

1228.8 614.4 409.6 307.2 2/3[ 1 ]

1/3[ 1 ]

2/9[ 1 ]

1/5[1.2][12] 12288 QPSK 1843.2 921.6 614.4 409.6 ½ ¼ 1/5 1/5


54

Reverse Link Channel Structure

PilotChannel

(All 0's)

Primary PilotBPSK(I) (16 chips)

DRC Channel[ 4-bit Rate,3-bit Sector ]

(7-Bits)

BiorthogonalEncoder (Q) (64 Symbols)

W016

Pri Pilot Gain

(32 chips)W28

32

DRC Gain

(1024 chips)

(L1 slots)W8

16 Repeat( 2 L1 ) (2048 L1 chips)

DSC Channel[Cell Selection]

(3-Bits)

BiorthogonalEncoder (Q) (4 Symbols)

DSC Gain

(128 chips)

L2slots)

W1232 Repeat

( 8 * L2 )

(1024 L2chips)

ACK Channel

(1-Bit)

BPSK(I)

ACK Gain

(32 chips)

(1 slot)

W1232 Repeat

( 32 ) (1024 chips)

TDM1 : 1

Data-0Channel

(CodeSymbols)

BPSK (Q)or

QPSK

Data Gain 0

W24

(4 chips)

W12

(2 chips)

Data-1Channel

(CodeSymbols)

QPSK

COMPLEX

SIGNAL

SUMMER

RRI

(7-Bits)

BiorthogonalEncoder (I) (64 Symbols)

(4 slots)

(8192 chips)

4-bit Payload Size,3-bit SubPkt ID

(MSB of SubPktID = 0)

(1024 chips)

Repeat( 8 )

W416

RRI Gain

DataGain1DataGain0 = 0 or DataGain1 = 0 orDataGain1 = sqrt(2) * DataGain0

Aux Pilot Gain

Auxiliary Pilot

DelayL2 slots

latest trends and new enhancements in 3g wireless communications rao yallapragada senior director,...

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