Internal Use Only ▲ Customer Service Department of CDMA Division EVDO Basic Principle EVDO...

Internal Use Only ▲

Customer Service Department of CDMA Division

EVDO Basic Principle

EVDO Overview

The Key Technologies of EVDO

The Commercial Application of EVDO

EVDO Network Structure

EVDO Channel



• What is the EVDO ?• the advantages of the EVDO ;• the difference of the 1x and EVDO;



Abbreviations Abbreviations

• 1xEV － EVolution of cdma2000 1X• 1xEV-DO － Data Only or Data Optimized• HDR － High Data Rate• HRPD － High Rate Packet Data• AN － Access Network • AT － Access Terminal • 3GPP2 C.S0024: cdma2000 High Rate Packet Data Air

Interface Standards



EV-DO EvolutionEV-DO Evolution

• Natural evolution of CDMA2000 1xNatural evolution of CDMA2000 1x• Enjoy surfing In 3G service ahead of timeEnjoy surfing In 3G service ahead of time

IS-95B CDMA2000CDMA20001xEV-DO1xEV-DO

IS-95AIS-95ACDMA2000CDMA20001xEV-DV1xEV-DV

CDMA2000-1xCDMA2000-1xRelease 0Release 0Release ARelease A



1xEV-DO basic features1xEV-DO basic features

• Allocate one 1.25MHz bandwidth, data only ；• Forward link rate: from 38.4kbps to 2.4Mbps ， R

everse link rate: from 9.6kbps to 153.6kbps ；• Same RF characteristic with 1x/IS-95 ；• Adopting a series revolutionary technique in air int

erface to accelerate data traffic 。



EV-DO Exciting Feature(1)EV-DO Exciting Feature(1)

Feature Item CDMA 2000 1X(1.25M) EV-DO(1.25M)

Service Voice and data Data only

Transfer rate IS95<14.4kbps

1x<153.6kbps/307.2kbps

FL<2.4Mbps/3.1Mbps

RL<153.6kbps/1.8Mbps

Division multiplex CDM for both Forward: TDM+CDM,

reverse: CDM

Handoffs Hard Handoff and Soft Handoff Both in FL ， RL

VHO in FL

Soft Handoff in RL

Power Control and

Rate Control

Fast Power Control Both

In FL ， RL

No Rate Control

Rate Control ＋ Power Control in RL

Rate Control in FL



Old handset can be used in new network, and new handset can be used in old network. Handset availability!

Backward and Forward CompatibilityBackward and Forward Compatibility



Leverage Current Investment: Sharing the same RF with 95/1X

Insert new EVDO channel cards and software upgradeFlexible Network Configuration:

Can be used as a stand-alone network or together with

an CDMA2000-1X network

EV-DO Exciting Feature(2)EV-DO Exciting Feature(2)



More Advanced Features of Rev. AMore Advanced Features of Rev. AImproved Forward Link

– Larger Payloads Drive Data Rates To 3.1Mbps– Improved MAC Supports Over 100 Users Per

Sector– Packet Division Multiplexing Improves

Performance In Good Channel Conditions

Improved Reverse Link– Up 1.8 Mbps Data Rate– Throughput and Latency Gains With Hybrid ARQ– Improved Packing Efficiency

Enhanced Quality of Service (QoS)– Inter-User – Priority by User– Intra-User – Priority by Application– Error Reduction in BTS– Admission Control– Adaptive Scheduler for delay sensitive Applications– Quick Connect with Adaptive Quick Start

Broadcast/ Multicast (BCMCS)– Multimedia content to multiple users

Improved support for real-time packet applications, including

VoIP, Gaming, Video Streaming

Can leverage advanced all-IP architectures, IMS support !

Enhanced capabilities to enable service flexibility and new

revenue generating features



• the commercial application of EVDO



1xEV-DO commercialization by CDMA operators



• the CDMA Development Process of ZTE



In November 2001, launched large-scale research and development in cdma2000 1xEV-DO products. In February 2002, launched research and development in cdma2000 base station system based on all-IP technology. In June 2002, ZTE, for the first time, exhibited complete cdma2000 1x EV-DO equipment on Hong Kong 3G annual fair.In October 2003, commissioned a field trial cdma2000 1x EV-DO.In June 2004, had the capability to supply cdma2000 1x EV-DO products in batch.In July 2004, commissioned a field trial cdma2000 1x Release A.In November 2004, put cdma2000 1x Release A and cdma2000 1x EV-DO products into commercial operation.In 2004, launched research and development in cdma2000 1x EV-DV products.



ZTE CDMA Wireless Solution

ZXC10-BSCB/PCF

ZXCBTS-M+ZXICS-C

Compact city zone

ZXC10-BTSB I2

ZXCBTS-M800

ZXC10-CBTS

ZXCBTS-RMBTS

ESU

RU_8

RU_2

ESU

RURU_1

ZXCBTS-M

ZXCBTS-R

ZXRPT-CSuburb or village

ZXC10-BTSB I1



South America

Brazil

Argentina

Nicaragua

……

South Africa

Kenya

Zambia

Angola

…...

North Africa

Algeria

Benin

Nigeria

……

Europe

Bulgaria

Norway

Turkey

……

CIS

Russia

Tajikistan

Uzbekistan

……

Asia Pacific

China

Indonesia

Mongolia

Vietnam

South Asia

Afghanistan

India

Pakistan

Nepal

……

CDMA 1X

CDMA 1X ＋ EV-DO

CDMA 1X ＋ GoTa

CDMA 1X ＋ EV-DO ＋ GoTa

EV-DO

Zte cdma2000 gobale application

Middle East

Egypt

Kuwait

Saudi Arabia

……



1.ZTE CDMA products have been successfully deployed in approximately 60 countries serving for approximately 100 operators, with a global capacity of 30 million lines for commercial use. Accordingly ZTE has become China’s largest telecommunication equipment exporter, and one of the leading CDMA equipment vendors in the world.

2.By December 2005, ZTE has captured 21.56% market share in China Unicom’s CDMA business, ranking third only next to Motorola (23.35%) and Lucent(22.14%).3.ZTE’s GoTa products have found widespread applications in over 20 countries such as Russia, Norway, Malaysia, etc. ZTE’s GoTa has become China-made digital trunking system with the widest applications home and abroad.

ZTE has built over 40 CDMA2000 1xEV-DO systems for commercial or trial use in more than 30 countries and regions such as Philippine, Vietnam, Pakistan, Mongolia, etc.

Zte cdma2000 gobale application



• EVDO Network Structure



AT

HLR

PDSN

AAA

BTS BSC PCF

MSC

A10/A11

HA

ANAAA

Access Network ( 1x and DO )

EVDO NETWORK STRUCTURE

AT： access terminal AN： access network， including BSC and BTS AN AAA： AAA server for access network



Simple Network StructureSimple Network Structure (End to End IP)(End to End IP)



Difference with 1x Reference NetworkDifference with 1x Reference Network

1xEV-DO is data only, so no interface to MSC/HLRThe Packet Data Domain

equipment （ PDSN 、 AAA 、 HA ） is same as 1X Independent Access network AAA server Two A interfaces added:- A12 for access system authentication- A13 for AT roaming home AN and Foreign AN interaction



1xEV-DO Channel Overview1xEV-DO Channel Overview



Forward Link Overview Forward Link Overview The transmission rate is the rate requested by AT on the reverse link. Dedicated to a single AT at any given instant of time.

Pilot is embedded in the traffic stream (as opposed to a continuous transmitted pilot in IS-95).

Paging and Sync Channels are combined into a single Control Channel whose messages are time multiplexed on the “single user” forward link.

Forward link transmission is organized as 26.66…ms frames. Each frame consists of sixteen 1.66…ms slots. Each slot contains 2048 chips. Each slot is divided into two half slots with 1024 chips each.

No soft handoff TDMed, full power and variable rate (38.4 kbps ~ 2457.6 kbps) Adaptive coding and modulation (R = ¼, 3/8, and ½; QPSK, 8PSK and 16Q

AM) Interleaving, puncturing, repetition and symbol demultiplexing

Quadrature Spreading, baseband Filtering and up-converting



Forward Channel StructureForward Channel Structure The 1xEV-DO forward channel structure

is of a time multiplexed of the following channels

– Pilot channel used by AT for all the following

Initial acquisition Phase & timing recovery Coherent demodulation and maximal ratio

combining – Medium access Control (MAC) consists

of three sub-channels: Reverse activity channel (RA) carries

reverse activity bit (RAB) stream Reverse power control (RPC), DRC Lock channel –user packets Traffic channel carries – Control channel carries messages



Forward Pilot ChannelForward Pilot Channel A Pilot channel is transmitted at all times by the sector on each a

ctive forward channel. The Pilot channel is an unmodulated BPSK signal assigned Wal

sh cover 0. The Pilot channel is sent as 96 chip bursts, each of which is loca

ted at the center of each half slot. The Pilot channel is transmitted at the full sector power.



Forward MAC ChannelForward MAC Channel

MAC channel is a CDM of Reverse Activity (RA) channel and Reverse Power Control (RPC) channels/DRC.

MAC channel is composed of up to 64 orthogonal Walsh channels and distinguish its uses (control & traffic preamble etc.) .

The RPC Channel and the DRC Lock Channel shall be time-division multiplexed.



Forward MAC ChannelForward MAC Channel RA channel belongs to a kind of broadcast channel , it is use

d to carry RAB information , controlling the reverse link’s payload dynamic . When AN finds the reverse payload too large , AN will transmit RA to AT and request AT adjust AT’s data rate;

RPC channel is used to carry reverse power control information ;

DRC Lock Channel carrys the information whether AN have received AT’s message, when AN cann’t demodulate AT’s message which is sent through DRC,AN will show AT send message anew;



MAC Channel and Preamble MAC Channel and Preamble Use Versus MACIndexUse Versus MACIndex



Forward Control ChannelForward Control Channel

The Control Channel Cycle period is 256 slots and synchronous with 1xEV-DO system time.

The AN transmits a Control Channel at a rate of 38.4 or 76.8kbps.

It is the combination of paging channel and sync channeling;



Time Division Multiplexed in FLTime Division Multiplexed in FL

In 1xEV-DO,the whole forward link is used as a shared “Fat Pipe”, TDMed by all users.

Specific time for which subscriber depending on the policy of forward transmission algorithm ： Round Robin, maximize data throughput of sector.

AT 3

AT 4

AT 2

AT 1

BS 1

BS 2

USER　 LEVEL



Reverse Link OverviewReverse Link Overview Reverse link parameters

- Reverse channel frames are 26.66ms; - Packet size is fixed at 26.66…ms; - Each slot contains 2048 PN chips; Output power characteristics are similar to CDMA2000 1X

- Access channel operation is similar to CDMA2000 1X - Closed & open loop power controls the mean output power of pilot and MAC

channels - The power levels for data are adjusted based on selected data rate Traffic channel

- In-phase component is a CDM of pilot/RRI and ACK channels - Quad-phase component is a CDM of DRC and data channels - Independent gains on DRC and ACK channel relative to pilot

DRC gain range (-9dB to +6dB)ACK gain range (-3dB to +6dB)

Access channel is composed of pilot channel and data channel - In-phase component consists of the pilot channel - Quad-phase component consists of the data channel



Reverse Channel StructureReverse Channel Structure

Each Traffic is direct sequence spread by a distinct user PN code sequence.The Access channels are identified by a distinct Access channel PN sequence per sector.Code Multiple： Pilot＝W016， DRC=W816， ACK=W48， Data=W24



Reverse Access ChannelReverse Access Channel

The Access Channel is used by the access terminal to initiate communication with the access network or to respond to an access terminal directed message.

The Access Channel consists of a Pilot Channel and a Data Channel.

The access terminal shall transmit information on the Access Channel at a fixed data rate of 9.6 kbps.



Reverse Traffic Channel OverviewReverse Traffic Channel Overview

Data channel: （ Pilot ）＋ RRI ＋ DRC ＋ ACK ＋ Data The Reverse Traffic Channel is used by the access termin

al to transmit user-specific traffic or signaling information to the access network. The Reverse Traffic Channel consists of a Pilot Channel, an RRI Channel, a DRC Channel, an ACK Channel, and a Data Channel.

The access terminal shall support transmission of information on the Data Channel of the Reverse Traffic Channel at data rates of 9.6, 19.2, 38.4, 76.8, and 153.6 kbps. The data rate used on the Data Channel is specified by the Reverse Traffic Channel MAC Protocol.



Reverse Traffic Pilot / RRI ChannelReverse Traffic Pilot / RRI Channel Pilot channel – Unmoduated symbols with binary value . – Giving an assistance coherent demodulation achieves better receiv

er performance (reduces the required Eb/No) . RRI channel – Reports data rate of the current reverse link data packet. • Represented by 3-bit RRI symbol, sent once per data packet • One-to-one mapped to reverse data rates – Each RRI symbol maps into a 7-bit codeword. – Time multiplexed with pilot symbols on every slot.



Reverse Traffic ACK ChannelReverse Traffic ACK Channel The ACK channel transmits a ‘0’ bit if a data packet has been received

successfully, and a ‘1’ if not in order to indicate whether a data packet on the forward traffic channel has been received successfully.

The ACK channel is generated by taking a single ACK bit, repeating this bit 128 times;

The ACK channel bit is transmitted at 9.6kbps in response to every FTC preamble that the AT detects is directed to it;

By using ACK channel in RL, AN can early terminate multi-slot packet transmission， and increased the actual throughput, it is HARQ;



Reverse Traffic DRC ChannelReverse Traffic DRC Channel

AT sends the request of the desired data rate and best serving sector on the forward channel to AN over the DRC channel.

Desired serving sector in the Active Set is indicated by one of eight 8-ary Walsh functions.

Data rate is block encoded to yield 8-bit bi-orthogonal codewords. AT estimates C/I received forward channel and determines the su

pportable data rate and the requested sector for transmission in the active set.

Only the sector requested will transmit packets to the AT, after receiving 2 consecutive DRCs from AT.

The sector sends a data packet with a preamble to the AT at the rate requested by the DRC in the preceding slot.

Once the sector starts sending packets to an AT, it must continue to do so until the packet Tx is complete or an Ack bit is received.



Reverse traffic data can be transmitted from 9.6kbps to 153.6kbps.

All data transmitted on the reverse traffic channel shall be turbo encoded, block interleaved, sequence repeated, and orthogonally spread by Walsh function W24(++--).

Reverse Traffic Data ChannelReverse Traffic Data Channel



Reverse Link Power ControlReverse Link Power Control Reverse Link is power controlled similar to IS-95 /

CDMA2000 1X. AT transmitted power which is determined by both

open-loop and close loop power control. Based on measurements of reverse link signal quality,

sector continually sends up/down power control bits to the AT .

Using closed loop power control achieved , AT adjusts its Pilot/MAC output power with 0.5 dB or 1.0dB step sizes, based on power control bit received on forward link from AN.

Open loop estimate based on received forward link power.



• The key Technologies



Time Division Multiplexed in FLTime Division Multiplexed in FL

• In 1xEV-DO ， the whole forward link is used as a shared “Fat Pipe”, TDMed by all users.

AT 3

AT 4

AT 2

AT 1

BS 1

BS 2



Adaptive modulation and codingAdaptive modulation and coding

• 1xEV-DO can automatically adjust its FL data rate, modulation scheme, coding rate according to the feedback of FL channel SINR provided by AT.

• AT use DRC sub channel to inform AN



Fast Cell Site SelectionFast Cell Site Selection

At any instance there is only one serving sector that is transmitting data to a given AT ；

The serving sector is decided by AT and changes as the Forward channel’s SINR changed.

AT use DRC sub channel to infrom AN who is the serving sector

AP1AP1

AP4AP4

AP2AP2

AP3AP3

AP1AP1 AP2AP2

TimeTime

Serving APServing AP

t1t1

Serving AP changeServing AP change

Server before t1

Server before t1

Server after t1

Server after t1

current sector forward data rate

Pilot/MAC on FWD link Pilot/DRC/ACK/Traffic on REV Link

(AP’s in AT’s active set)

After handoff AP2 forward data rate



Serving Sector Selection illustrationServing Sector Selection illustration

Serving Sector Selection

-15

-14

-13-12

-11

-10

-9-8

-7

-6

-5

-4-3

-2

-1

01

2

3

0 2 4 6 8 10 12 14

time, sec

SIN

R, d

B

Sector 0

Sector 1

Serving Sector Index



Hybrid ARQHybrid ARQ

• By using ACK channel in RL, AN can early terminate multi-slot packet transmission ， and increased the actual throughput.



Reverse link rate controlReverse link rate control

• In 1x EV-DO specifications, AT’s reverse rate can be freely adjusted by AT from 9.6kbit/s to 153.6kbits. In order to avoid all the AT become unavailable, the workload of reverse links must be constrained to prevent too many users in the same sector from transferring data to AN at a high rate.

NotBusy

9.6kbps

19.2kbps

153.6kbps

P1

38.4kbps

76.8kbps

P2 P3 P4

Busy9.6

kbps19.2kbps

153.6kbps

q1

38.4kbps

76.8kbps

q2 q3 q4



Reverse link Power controlReverse link Power control

• Power control is essential to the system maximization. The forward power control is not required in 1x EV-DO because of its constant power. Therefore, power control is mainly adopted by reverse channels.

• Reverse Power control includes

Opened-loop power control 、 Closed-loop power control 、



Virtual soft handoff in forward linkVirtual soft handoff in forward link

• In The forward Virtual Handoff, there’s only one sector sends data to the terminals at a particular time in the AT active set. According to the quality of each received pilot, AT can use the DRC_Cover to specify the sectors which are expected to transfer data. In AN, all the sectors within the active set are listening to the reverse channels of the AT. AN decides which sector is the Serving Sector of the AT according to the DRC channel received.

• There’s no signaling messages exchange between AN and AT in the forward Virtual Handoff as it is very quick. It only takes up one sector’s forward air resource at anytime. The usability of forward channels are improved significantly.



Dual Mode Operation with 1x/DODual Mode Operation with 1x/DO

• As 1xEV-DO supports only data traffic, a total voice and data solution needs integrating cdma2000 1x and 1xEV-DO ；

• Packet data traffic can be handoff from 1x to DO, and dual mode terminal can monitor both system’s control channel, so even active in DO system it will not lose any voice terminated calls in 1x system.



Thank You !

Internal Use Only ▲ Customer Service Department of CDMA Division EVDO Basic Principle EVDO...

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