intro to telecom and cdma2000 principle

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Introduction to Telecommunication and CDMA2000 Principle

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Intro to Telecom and CDMA2000 Principle

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Page 1: Intro to Telecom and CDMA2000 Principle

Introduction to Telecommunication and CDMA2000 Principle

Introduction to Telecommunication and CDMA2000 Principle

Page 2: Intro to Telecom and CDMA2000 Principle

ObjectivesObjectives

After this presentation, you will be familiar with:

the development of mobile communication system the structure of CDMA2000 network the number planning in CDMA2000 network the techniques used by CDMA system including:

source coding, channel coding, interleaving, scrambling,

spreading and modulation etc.power control, soft handoff, RAKE receiverF-PCH,F-PICH,F-SYNCH,F-FCH,F-SCH,R-ACH,R-PICH Long code, short code and Walsh code

Page 3: Intro to Telecom and CDMA2000 Principle

Course OrganizationCourse Organization

Chapter 1: Introduction

Chapter 2: CDMA Techniques & Technologies

Chapter 3: CDMA Air Interface

Chapter 4: CDMA Core Networks

Chapter 5: CDMA Number Planning

Page 4: Intro to Telecom and CDMA2000 Principle

1st Generation 1980s (analog)

2nd Generation 1990s (digital)

3rd Generation current (digital)

3G provides: Complete integrated service solutions High bandwidth Unified air interface Best spectral efficiency and ……………… a step towards PCS

AMPS

Analog to DigitalTACS

NMT

OTHERS

GSM

CDMA IS95

TDMA IS-136

PDC

UMTS WCDMA

CDMA 2000

TD-SCDMA

Development of Mobile Communications Development of Mobile Communications Introduction

Voice to Broadband

Page 5: Intro to Telecom and CDMA2000 Principle

Transmission TechniquesTransmission Techniques

Traffic channels: different users are assigned unique code and transmitted over the same frequency band, for example, WCDMA and CDMA2000

Traffic channels: different frequency bands are allocated to different users,for example, AMPS and TACS

Traffic channels: different time slots are allocated to different users, for example, DAMPS and GSM

FrequencyTime

Power

FrequencyTime

Power

FrequencyTime

Power

FDMA

TDMA

CDMA

User

User

User

User User

User

Introduction

Page 6: Intro to Telecom and CDMA2000 Principle

TDMATDMA

Frequency

Time

Power

use

r

use

r

use

r

use

r

use

r

Introduction

Page 7: Intro to Telecom and CDMA2000 Principle

3G Objectives3G Objectives

3G is developed to achieve:

Universal frequency band for standard and seamless

global coverage

High spectral efficiency

High quality of service with complete security and

reliability

Easy and smoothly transition from 2G to 3G, compatible

with 2G

Provide multimedia services, with the rates:

Vehicle environment: 144kbps

Walking environment: 384kbps

Indoor environment: 2Mbps

Introduction

Page 8: Intro to Telecom and CDMA2000 Principle

Standards for 3G

Standards for 3G

3G system

CDMA2000

3GPP2

FDD mode

WCDMA

3GPP

FDD mode

TD-SCDMA

CWTS

TDD mode

Introduction

Page 9: Intro to Telecom and CDMA2000 Principle

A Comparison b/w 3G standards A Comparison b/w 3G standards

WCDMA CDMA2000 TD-SCDMA

Receiver type RAKE RAKE RAKE

Close loop power control Supported Supported Supported

Handoff Soft/hard handoff

Demodulation mode Coherent

Chip rate (Mcps) 3.84 N*1.2288 1.28

Transmission diversity mode

TSTD, STTDFBTD

OTD, STS No

Synchronizationmode

Asynchronous Synchronous Asynchronous

Core network GSM MAP ANSI-41 GSM MAP

CoherentCoherent

Soft/hard handoff Soft/hard handoff

Introduction

Page 10: Intro to Telecom and CDMA2000 Principle

IS95A 9.6kbps

IS95B 115.2kbps

CDMA2000

307.2kbps

Heavier voice service capacity ;

CDMA2000 3X

CDMA2000 1X EV

1X EV-DO

1X EV-DV

1995 1998

20002003

Development of CDMADevelopment of CDMA

Higher spectrum efficiency and network capacity

Higher packet data rate and more diversified services

Smooth transit to 3G

Introduction

Page 11: Intro to Telecom and CDMA2000 Principle

Frequency Allocation In CDMA2000Frequency Allocation In CDMA2000

Band Class 0 and Spreading Rate 1

Transmit Frequency Band (MHz)

Block

Designator

CDMA Channel

Validity

CDMA

Channel

Number

Mobile Station Base Station

A(10MHz) Valid 1-311 825.030-834.330 870.030-879.330

B(10MHz) Valid 356-644 835.680-844.320 880.680-889.320

A’(1.5MHz) Valid 689-694 845.670-845.820 890.670-890.820

B’(2.5MHz) Valid 739-777 847.170-848.310 892.170-893.310

Introduction

The transmit frequence point for Base Station is computed by:

F=870+N*0.03

N: CDMA Channel Number

Page 12: Intro to Telecom and CDMA2000 Principle

Frequency Allocation In CDMA2000Frequency Allocation In CDMA2000

Band Class 1 and Spreading Rate 1

Introduction

Transmit Frequency Band (MHz)

Block

Designator

CDMA

Channel

Validity

CDMA

Channel

Number

Mobile Station Base Station

A(15MHz) Valid 25-275 1851.250-1863.750 1931.250-1943.750

D(5MHz) Valid 325-375 1866.250-1868.750 1946.250-1948.750

B(15MHz) Valid 425-675 1871.250-1883.750 1951.250-1963.750

E(5MHz) Valid 725-775 1886.250-1888.750 1966.250-1968.750

F(5MHz) Valid 825-875 1891.250-1893.750 1971.250-1973.750

C(15MHz) Valid 925-1175 1896.250-1908.750 1976.250-1988.750

The transmit frequence point for Base Station is computed by:

F=1930+N*0.05

N: CDMA Channel Number

Page 13: Intro to Telecom and CDMA2000 Principle

CDMA2000 1X Network StructureCDMA2000 1X Network Structure

MS: Mobile Station BTS: Base Transceiver StationBSC: Base Station Controller MSC: Mobile Switching CenterHLR :Home Location Register VLR: Visitor Location RegisterPCF: Packet data Control Function PDSN: Packet Data Service Node HA: Home Agent FA: Foreign Agent SCP: Service Control Point Radius: Remote Authentication Dial-in User Service

Abis

A1(Signaling)

A2(Traffic)

A11(Signaling)

A10(Traffic)

A3(Signaling &

Traffic)

A7(Singaling)

Introduction

Page 14: Intro to Telecom and CDMA2000 Principle

Course ContentsCourse Contents

Chapter 1 Introduction

Chapter 2 CDMA Techniques & Technologies

Chapter 3 CDMA Air Interface

Chapter 4 CDMA Core Networks

Chapter 5 CDMA Number Planning

Page 15: Intro to Telecom and CDMA2000 Principle

CorrelationCorrelation

(a)

(b)

Correlation 100% so the functions are parallel

Correlation 0% so the functions are orthogonal

CDMA Techniques & Technologies

+1

-1

+1

-1

+1

-1

+1

Page 16: Intro to Telecom and CDMA2000 Principle

Orthogonal FunctionOrthogonal Function

Orthogonal functions have zero correlation. Two binary

sequences are orthogonal if their “XOR” output contains equal

number of 1’s and 0’s

0000

0101

0101

EXAMPLE:

CDMA Techniques & Technologies

1010

0101

1111

Page 17: Intro to Telecom and CDMA2000 Principle

Information spreading over orthogonal codesInformation spreading over orthogonal codes

CDMA Techniques & Technologies

1 0 0 1 1

0110 0110 0110 0110 0110

1001 0110 0110 1001 1001

User Input

Orthogonal Sequence

Tx Data

+1

-1

+1

-1

Page 18: Intro to Telecom and CDMA2000 Principle

Information recoveryInformation recoveryCDMA Techniques & Technologies

1 0 0 1 1+1

-1

Rx Data 1001 0110 0110 1001 10010110 0110 0110 0110 01101111 0000 0000 1111 1111

Correct Function

? ? ? ? ?

Rx Data 1001 0110 0110 1001 10010101 0101 0101 0101 01011100 0011 0011 1100 1100

Incorrect Function

Page 19: Intro to Telecom and CDMA2000 Principle

Spreading and De-spreadingSpreading and De-spreading

information pulse interference White noise

The improvement of time-domain information rate means that the bandwidth of spectrum-domain

information is spread.

S(f) is the energy density.

f

S( f)

The spectrum before spreading

information

f0

The spectrum before despreading

informationInterference/noise

S( f)

f0 f f0

The spectrum after despreading

information

Interference/noise

S( f)

f

The spectrum after spreading

information

f0

S( f)

f

CDMA Techniques & Technologies

Page 20: Intro to Telecom and CDMA2000 Principle

Signal flowSignal flow

InterleavingSource coding

Convolution &Interleaving

Scrambling Spreading Modulation

RF transmission

Source decoding

deinterleavingDecovolution &Deinterleaving

Unscrambling De-spreading Demodulation RF receiving

CDMA Techniques & Technologies

Page 21: Intro to Telecom and CDMA2000 Principle

Common Technical Terms

Common Technical Terms

Bit, Symbol, Chip:

A bit is the input data which contain information

A symbol is the output of the convolution, encoder, and the block

interleaving

A chip is the output of spreading

Processing Gain:

Processing gain is the ratio of chip rate to the bit rate.

The processing gain in IS-95 system is 128, about 21dB.

Forward direction: Information path from base station to

mobile station

Reverse direction: Information path from mobile station to

base station

CDMA Techniques & Technologies

Page 22: Intro to Telecom and CDMA2000 Principle

In a typical duplex call, the duty ratio is less than 35%. To achieve

better capacity and low power consumption, base station reduces

its transmission power.

Source CodingSource Coding

Vocoder:

8K QCELP

13K QCELP

EVRC

Characteristics

Support voice activity

CDMA Techniques & Technologies

Page 23: Intro to Telecom and CDMA2000 Principle

Channel CodingChannel Coding

Convolution code or TURBO code is used in channel encoding

Constraint length=shift register number+1.

Encoding efficiency= (total input bits / total output symbols)

convolution encoder

Input (bits)

Output (symbols)

CDMA Techniques & Technologies

Page 24: Intro to Telecom and CDMA2000 Principle

Turbo Code Turbo Code

Turbo code is used during the transmission of large data packet.

Characteristics of the Turbo code:

The input information is encoded twice and the two output codes can

exchange information with each other during decoding.

The symbol is protected not only by the neighborhood check bits, but

also by the separate Check Bits.

The performance of a Turbo code is superior to that of a convolution

code.

CDMA Techniques & Technologies

Page 25: Intro to Telecom and CDMA2000 Principle

InterleavingInterleaving

The direction of the data stream

1 2 873 64 5

1 2 873 64 5

1 2 873 64 5

1 2 873 64 5

1 2 873 64 5

1 2 873 64 5

1 2 873 64 51 2 873 64 51 2 873 64 5

1 2 873 64 5

1 1 111 11 1

2 2222

7 7 777 77 7

6 6 666 66 6

3 3 333 33 3

4 4 444 44 4

1 2 873 64 51 2 873 64 55 5 555 55 5

8 8 888 88 8interleaving

CDMA Techniques & Technologies

2 2 2

Page 26: Intro to Telecom and CDMA2000 Principle

Out

0 0 1

1 1 0

Scrambling (M) sequenceScrambling (M) sequence

Two points are important here: Maximum number of shift register (N)

Mask

The period of out put sequence is 2N-1 bits

Only sequence offset is change when the mask is changed

PN stands for Pseudorandom Noise sequence

CDMA Techniques & Technologies

Page 27: Intro to Telecom and CDMA2000 Principle

Long Code

Long Code

The long code is a PN sequence with period of 242-1chips

The functions of a long code:

Scramble the forward CDMA channel

Control the insertion of power control bit

Spread (identify) the information on the reverse CDMA channel to

identify the mobile stations

CDMA Techniques & Technologies

Page 28: Intro to Telecom and CDMA2000 Principle

PNa

PNc

PNb

Short CodeShort Code

CDMA Techniques & Technologies

Short code is a PN sequence with period of 215 chips Sequence with different time offset is used to distinguish

different sectors

Minimum PN sequence offset used is 64 chips, that is, 512 PN

offsets are available to identify the CDMA sectors (215/64=512).

Page 29: Intro to Telecom and CDMA2000 Principle

Walsh CodeWalsh Code

W2n=Wn Wn

Wn Wn

W1=0

W2= 0 0

0 1

W4 =

0 00 1

0 00 1

0 00 1

Walsh code

64-order Walsh function is used as a spreading function and each Walsh code is orthogonal to other.

Walsh Code is one kind of orthogonal code.

A Walsh can be presented by Wim where ith (row) is the posi

tion and m is the order. For example, W24 means 0101 code i

n W4 matrix

CDMA Techniques & Technologies

1 11 0

Page 30: Intro to Telecom and CDMA2000 Principle

In forward direction, each symbol is spread with Walsh code

Walsh code is used to distinguish the user in forward link

For IS95A/B, in the reverse, every 6 symbols correspond to one

Walsh code. For example, if the symbol input is 110011,the

output after spreading is W5164 (110011=51).

For CDMA2000, in the reverse, Walsh function is used to define

the type of channel (RC 3-9)

Walsh CodeWalsh CodeCDMA Techniques & Technologies

Page 31: Intro to Telecom and CDMA2000 Principle

Variable Walsh codesVariable Walsh codes

64

48

16

32

12

9600 19200 38400 76800 153600 307200 614400

Data rate -bps-

W01 =0

W02 =00

W12 =01

W04 =0000

W24 =0011

W14 =0101

W34 =0110

W08 =00000000

W48 =00001111

W28 =00110011

W68 =00111100

W18 =01010101

W58 =01011010

W38 =01100110

W78 =01101001

( W016 ,W8

16)

( W416 ,W12

16 )

( W216 ,W14

16 )

( W616 ,W14

16 )

( W116 ,W9

16 )

( W516 ,W13

16 )

( W316 ,W11

16 )

( W716 ,W15

16 )

The different Walsh codes corresponding to different data rates

CDMA Techniques & Technologies

Page 32: Intro to Telecom and CDMA2000 Principle

Modulation-QPSKModulation-QPSK

I

Q

I channel PN sequence1.2288Mcps

Q channel PN sequence

1.2288Mcps

Baseband filter

Baseband filter

Cos(2pfct)

Sin(2pfct)

I(t)

Q(t)

s(t)A

1.2288Mcps: the PN chip rate of the system.

After being spread, all the forward channels in the same carrier are

modulated by means of QPSK(OQPSK in the reverse), converted

into simulation signals and transmitted after clustering.

CDMA Techniques & Technologies

Page 33: Intro to Telecom and CDMA2000 Principle

Power Control

Handoff

Diversity and RAKE

CDMA Techniques & Technologies

Page 34: Intro to Telecom and CDMA2000 Principle

Power ControlPower Control

Reverse power control Open loop power control

Closed loop power control

Inner loop power control: 800 Hz

Outer loop power control

Forward power control Message transmission mode:

threshold transmission

periodic transmission

Closed loop power control

.

CDMA Techniques & Technologies

Page 35: Intro to Telecom and CDMA2000 Principle

Reverse Open Loop Power ControlReverse Open Loop Power Control

• The transmission power required by the mobile station is determined by

the following factors:

Distance from the base station

Load of the cell

Circumstance of the code channels

• The transmission power of the mobile station is relative to its received

power.

BTSMobile

Reverse Open LoopPower Control

BTS

BTS

Transmitting Power

CDMA Techniques & Technologies

Page 36: Intro to Telecom and CDMA2000 Principle

Reverse Closed Loop Power ControlReverse Closed Loop Power Control

BTS

Power Control Bit

Eb/Nt Value FER Value

Inner Loop Power Control

Outer Loop Power Control

Change in Eb/Nt Value

CDMA Techniques & Technologies

BSC

BTS

Page 37: Intro to Telecom and CDMA2000 Principle

Forward Power ControlForward Power Control

MS measures the frame quality and informs the base station

to the result i.e. whether it is in the threshold or periodical

mode. Base station determines whether to change the

forward transmitting power or not.

In IS-95 system, the forward power control is slow but in

CDMA2000 system it is fast.

CDMA Techniques & Technologies

Message Transmission Mode

Page 38: Intro to Telecom and CDMA2000 Principle

Forward Closed Loop Power ControlForward Closed Loop Power Control

Compared with IS-95 system, CDMA2000 the forward

quick power control is fast.

Power Control Bit

Eb/Nt Value

CDMA Techniques & Technologies

BTS

Page 39: Intro to Telecom and CDMA2000 Principle

HandoffHandoff

Soft handoffIt is a process of establishing a link with a target sector before breaking the link with the serving sector

Softer handoffLike the soft handoff, but the handoff is occurred between multi-sectors in the same base station

Hard handoffHard handoff occurs when the two sectors are not synchronized or are not on the same frequency. Interruption in voice or data communication occurs but this interruption does not effect the user communication

CDMA Techniques & Technologies

Page 40: Intro to Telecom and CDMA2000 Principle

Soft/Softer HandoffSoft/Softer Handoff

• Multi-path combination in the BSC during soft handoff

• Multi-path combination in the BTS during softer handoffs

Combine all the power from each

sector

Power received from a single sector

CDMA Techniques & Technologies

Page 41: Intro to Telecom and CDMA2000 Principle

Pilot SetPilot Set

ActiveSet

CandidateSet

NeighborSet

Remaining Set

The pilot set, corresponding to the base station being connected

The pilot set, not in the active set but potential to be demodulated

The pilot set, not included in the active set or the candidate set but being possible to be added in the candidate set

Other pilot sets

the set of the pilots having same frequency but different PN sequence offset

CDMA Techniques & Technologies

Page 42: Intro to Telecom and CDMA2000 Principle

T_ADD,T_DROP,T_TDROPT_ADD,T_DROP,T_TDROP

Time

Ec/Io

Sector A Sector

B

Guard Time(T-TDROP)

Add Threshold (T_ADD)

DropThreshold (T_DROP)

Soft Handoff Region

T_ADD, T_DROP and T_TDROP affect the percentage of MS in handoff.

T_ADD & T_DROP is the standards used to add or drop a pilot.

T_DROP is a timer.

CDMA Techniques & Technologies

Page 43: Intro to Telecom and CDMA2000 Principle

Comparison ThresholdComparison Threshold

Pilot P1

Pilot P2

Pilot P0

t0

T_COMP×0.5dB

t1 t2

T_ADD

Pilot strength

P0-Strengh of Pilot P0 in Candidate Set.

P1,P2-Stength of Pilot P1,P2 in Active Set.

t0-Pilot strength Measurement Message Sent, P0>T_ADD

t1-Pilot strength Measurement Message Sent, P0>P1+T_COMP*0.5dB

t2 -Pilot strength Measurement Message Sent, P0>P2+T_COMP*0.5dB

CDMA Techniques & Technologies

Page 44: Intro to Telecom and CDMA2000 Principle

Transition Between Pilot SetsTransition Between Pilot Sets

T_ADD

T_DROP

Pilot 1

Pilot strength

Pilot 2

T_TDROP

T_TDROP

NeighborSet

CandidateSet

ActiveSet

CandidateSet

NeighborSet

TIME1 2 3 4 5 6 7 8

CDMA Techniques & Technologies

Page 45: Intro to Telecom and CDMA2000 Principle

Transmit DiversityTransmit Diversity

Time diversity Block interleaving, error-correction

Frequency diversity The CDMA signal energy is distributed on the whole 1.23MHZ

bandwidth.

Space diversity The introduction of twin receive antennas .

The RAKE receivers of the mobile station and the base station

can combine the signals of different time delay.

During a handoff, the mobile station contacts multiple base

stations and searches for the strongest frame

CDMA Techniques & Technologies

Page 46: Intro to Telecom and CDMA2000 Principle

Transmission DiversityTransmission Diversity

The forward transmission diversity types in

CDMA2000 1X are

TD (Transmit Diversity) OTD (Orthogonal Transmit Diversity)

– The data stream is divided into two parts, which will be spread by

the orthogonal code sequence, and transmitted by two antennas.

STS (Space Time Spreading)

– All the forward code channels are transmitted by the multi-

antennas.

– Spread with the quasi-orthogonal code

Non-TD

CDMA Techniques & Technologies

Page 47: Intro to Telecom and CDMA2000 Principle

Transmission DiversityTransmission Diversity

The Transmission Diversity Technology enhances the receive performance of MS.

Transmission diversity

processing

Data stream 1

Data stream 2

Data stream Restoring data stream

Path 1

Path 2

Antenna 2

Antenna 1

CDMA Techniques & Technologies

Page 48: Intro to Telecom and CDMA2000 Principle

The Principle of RAKE ReceiverThe Principle of RAKE Receiver

RAKE antennas help to overcome on the multi-path fading and enhance

the receive performance of the system

Receive set

Correlator 1

Correlator 2

Correlator 3

Searcher correlator Calculate the time delay and signal strength

Combiner The combined signal

tt

s(t) s(t)

CDMA Techniques & Technologies

Page 49: Intro to Telecom and CDMA2000 Principle

Course ContentsCourse Contents

Chapter 1 Introduction

Chapter 2 CDMA Techniques & Technologies

Chapter 3 CDMA Air interface

Chapter 4 CDMA Core Network

Chapter 5 CDMA Number Planning

Page 50: Intro to Telecom and CDMA2000 Principle

Physical Channel in IS-95APhysical Channel in IS-95A

Forward channel Forward Pilot Channel Forward Sync Channel Forward Paging Channel Forward Traffic Channel (including power control sub-

channel)

Reverse channel Access Channel Reverse Traffic Channel

CDMA Air Interface

Page 51: Intro to Telecom and CDMA2000 Principle

Pilot channel(all-zeros)

W064

Pilot ChannelPilot Channel

A pilot channel:

Assist mobile station to be connected with CDMA network

Handles multi-path searching

Provide the phase reference for coherent demodulation and help the mobile

station estimate the transmission power

The mobile station measures and compares the pilot channel powers from

the base stations during the handoff

Forward pilot channel is spread over W0 and modulated with short code directly

BTS transmits the pilot channel continuously

CDMA Air Interface

Page 52: Intro to Telecom and CDMA2000 Principle

To

QP

SK

cod

er

2.4kbps 4.8kbps 4.8kbps

Code symbol

Repetitive code

symbol

1.2kbps

Convolution encoderr=1/2,K=9

symbol repetition

Block interleaving

Sync Ch bits

W3264

Sync ChannelSync Channel

The sync channel is used by the mobile station to synchronize with the network. W32 is used to spread Sync Channel.

The synchronization message includes: Pilot PN sequence offset: PILOT_PN

System time: SYS_TIME

Long code state: LC_STATE

Paging channel rate: P_RAT

Here note that, sync channel rate is 1200bps

CDMA Air Interface

Page 53: Intro to Telecom and CDMA2000 Principle

To

QP

SK

cod

er

Paging channel bits

19.2/9.6Kbps 19.2kbps

19.2kbpsCode

symbol

9.6/4.8 kbps

Convolution encoder

r=1/2,K=9

Symbol repetition

Block interleaving

Paging channel address mask

Long code PN

generator

decimator

1.2288Mcps

19.2kbps

Repetitive code

symbol

Paging ChannelPaging Channel

The paging channel transmits: System parameters message

Access parameters

Neighbors list

CDMA channels list message

The paging channel accomplishes: Paging to MS

Assign traffic channel to MS

The frame length of a paging channel is 20ms

W1 ~ W7 are spared for the Paging Channels spreading

CDMA Air Interface

W164

Page 54: Intro to Telecom and CDMA2000 Principle

Forward Traffic ChannelForward Traffic Channel

I Ch PN sequence (1.2288 Mcps)

PN 1.2288 Mcps

Repetitive symbol

19.2kbps

8.6kbps9.6kbps

4.8kbps2.4kbps1.2kbps

Add frame quality indicator bits(12,10,8,6)

Add 8 encoded tail

bits

Convolution encoder

r=1/2,K=9

Symbol repetition

Forward traffic channal

(172/80/40 or

16bits/frame)

Block interleaver

19.2kbps

MUX

Long code generator

Power control bits

Q Ch PN sequence (1.2288 Mcps)

Baseband filter

I(t)

Q(t)decimator

+∑QPSK Modulation

4.0kbps2.0kbps0.8kbps

19.2ksybps9.6ksybps4.8ksybps2.4ksybps

Sin(2pfct)

Cos(2pfct)

is used to transmit data and signaling information.

Walsh code

CDMA Air Interface

decimator

+

+Baseband

filter

+

+

Page 55: Intro to Telecom and CDMA2000 Principle

Reverse Access ChannelReverse Access Channel

4.8 kbps (307.2kbps)

PN chips1.2288 McpsOrthogonal spreading

Repetitive symbol

8.8 kbps

Code symbol

14.4 kbps4.4 kbps 4.8 kbpsAdd 8 encoder tail

bits

Convolutionencoder

r=1/3,K=9

Symbol repetitionAccess

channel (80

bits/frame)

Block interleaving

28.8 kbps

Data burst randomizer

Long code PN

generator

Frame rate

Long code mask

Repetitive symbol

used by MS to initiate communication or respond to Paging Channel

Walsh code

CDMA Air Interface

I Ch PN sequence (1.2288 Mcps)

Baseband filter

I(t)

Q(t)

∑QPSK Modulation

Sin(2pfct)

Cos(2pfct)

+

+Baseband

filter

+

+

Q Ch PN sequence (1.2288 Mcps)

1/2 PN chips Delayed time=406.9ns

Page 56: Intro to Telecom and CDMA2000 Principle

Reverse Traffic ChannelReverse Traffic Channel

used to transmit data and signaling information

CDMA Air Interface

8.6kbps9.6kbps

4.8kbps2.4kbps1.2kbps

Add frame quality indicator bits(12,10,8,6)

Add 8 encoded tail

bits

convolution encoder

r=1/3,K=9

Symbol repetition

Reverse traffic channel

(172/80/40 or

16 bits/frame)

Block interleaver

4.0kbps2.0kbps0.8kbps

28.8Ksybps14.4Ksybps7.2Ksybps3.6Ksybps

4.8 kbps (307.2kbps)

PN chips1.2288 Mcps

Orthogonal spreading

Data burst randomizer

Long code PN

generator

Frame rate

Long code mask

Walsh code

I Ch PN sequence (1.2288 Mcps)

Baseband filter

I(t)

Q(t)

∑QPSK Modulation

Sin(2pfct)

Cos(2pfct)

+

+Baseband

filter

+

+

Q Ch PN sequence (1.2288 Mcps)

1/2 PN chips Delayed time=406.9ns

Page 57: Intro to Telecom and CDMA2000 Principle

Initialization of the MSInitialization of the MS

Synchronous Channel message contains the LC_STATE,

SYS_TIME, P_RAT, and synchronizes with the system.

CDMA Air Interface

BTS

Pilot channel

Synchronous channel

Paging channel

Access channel

Page 58: Intro to Telecom and CDMA2000 Principle

CDMA2000 Forward ChannelCDMA2000 Forward Channel

Forward CDMA2000 channel

F-CACH F-CPCCH F-PICH F-CCCH

F-DCCH F-FCHF-PC F-SCCH F-SCH

F-PICH F-TDPICH F-APICH F-ATDPICH

F-SYNCH F-TCH F-BCH F-PCH F-QPCH

subchannel (RC1~2) (RC3~9)

Note: Only the channels with black color are being implemented in Huawei equipment. The function of F-PICH, F-SYNCH, F-FCH, F-PC, F-SCCH, F-PCH are the same as those of IS95. We will only discuss F-SCH, F-QPCH F-DCCH in the following slides.

CDMA Air Interface

Page 59: Intro to Telecom and CDMA2000 Principle

Forward channelForward channel

These channels are newly defined in CDMA2000 system.

CDMA physical channels are classified in common channels and dedicated channels:

Common physical channels: Forward Pilot Channel(F-PICH)

Forward Synchronous Channel(F-SYNC)

Forward Paging Channel(F-PCH)

Forward Broadcast Control Channel(F-BCCH)

Forward Quick Paging Channel(F-QPCH)

Forward Common Power Control Channel(F-CPCCH)

Forward Common Assignment Channel(F-CACH)

Forward Common Control Channel(F-CCCH)

These channels are compatible with IS-95 system

Dedicated physical channel:

Forward Dedicated Control Channel(F-DCCH)

Forward Fundamental Channel(F-FCH)

Forward Supplemental Channel(F-SCH)

These channels are used to establish the connection between a base station and a

specific mobile station.

The CDMA2000 system adopts multiple data rates and the different combinations of

channels can achieve a performance superior to that in IS-95 system.

CDMA Air Interface

Page 60: Intro to Telecom and CDMA2000 Principle

F-QPCHF-QPCH

It transmits OOK-modulated signal which can be demodulated by

MS simply and rapidly.

The channel adopts 80ms as a QPCH timeslot. Each timeslot is

divided into paging indicators, configuration change indicators

and broadcast indicators, all of which are utilized to inform the

MS whether to receive paging message, broadcast message or

system parameters in the next F-PCH.

Rapid and simple demodulation. MS no need to monitor F-PCH

for long time, so the standby time is prolonged.

CDMA Air Interface

Page 61: Intro to Telecom and CDMA2000 Principle

F-SCHF-SCH

F-SCH is typically used for high speed data

applications, while F-FCH is used for common

voice and low speed data application.

When a data call is established, firstly, F-FCH will

be allocated to the user. If the speed of data for

user exceeds 9.6kbps, F-SCH will be allocated.

CDMA Air Interface

Page 62: Intro to Telecom and CDMA2000 Principle

F-DCCHF-DCCH

It is used for the transmission of specific user

signaling information during a call.

Each forward traffic channel may contain one F-DCCH.

Support 5ms frame.

Support discontinuous transmission.

CDMA Air Interface

Page 63: Intro to Telecom and CDMA2000 Principle

Forward Radio Configuration (RC)Forward Radio Configuration (RC)

Radio Configuration(RC):

A set of Forward Traffic channel and Reverse Traffic Channel transmission

formats that are characterized by physical parameters such as data rates,

modulation characteristics, and spreading rate.

Spreading Rate: Equivalent to chips rate, e.g., 1.2288Mcps.

Radio Configuration

Spreading Rate

Max Data Rate* (kbps)

Effective FEC Code Rate

OTD Allowed

FEC Encoding Modulation

1** 1 9.6 1/2 No Conv. BPSK 2** 1 14.4 3/4 No Conv BPSK

3 1 153.6 1/4 Yes Conv and Turbo QPSK4 1 307.2 1/2 Yes Conv and Turbo QPSK5 1 230.4 3/8 Yes Conv and Turbo QPSK6 3 307.2 1/6 Yes Conv and Turbo QPSK7 3 614.4 1/3 Yes Conv and Turbo QPSK8 3 460.8 1/4 or 1/3 Yes Conv and Turbo QPSK9 3 1036.8 1/2or 1/3 Yes Conv and Turbo QPSK

** Same as IS95

CDMA Air Interface

Page 64: Intro to Telecom and CDMA2000 Principle

Reverse ChannelReverse Channel

Reverse CDMA2000 channel

R-ACHR-TCH

operation(RC1~2)

R-EACH operation

R-CCCH operation

R-SCCH

R-FCH

R-TCH operation (RC3~6)

R-EACH

R-PICH

R-CCCH

R-PICH

R-DCCH

R-PICH

0~7 0~1

R-SCH

R-FCH

0~2

0~1

subchannel

R-PC

Only the channels in dark color are used in Huawei equipment. The function of R-ACH,R-FCH,R-SCCH are the same as those in IS95. We will only discuss R-PICH,R-SCH in the following slides.

CDMA Air Interface

Page 65: Intro to Telecom and CDMA2000 Principle

Types of Reverse ChannelTypes of Reverse Channel

Reverse channel includes reverse common channel

and reverse dedicated channel. Reverse common channel:

Reverse Access Channel(R-ACH)

Reverse Enhanced Access Channel(R-EACH)

Reverse Common Control Channel(R-CCCH)

Reverse Dedicated Channel

Reverse Pilot Channel(R-PICH)

Reverse Dedicated Control Channel(R-DCCH)

Reverse Fundamental Channel(R-FCH)

Reverse Supplemental Channel(R-SCH)

Reverse Supplemental Code Channel (R-SCCH)

CDMA Air Interface

Page 66: Intro to Telecom and CDMA2000 Principle

MUX A

Pilot( all '0's)

Power Control Bit

N is the Spreading Rate number

Pilot PowerControl

Power Control Group= 1536 NPN Chips

384 NPN Chips

Reverse Pilot Channel

R-PICHR-PICH

The Function of Reverse Pilot Channel

Initialization

Tracing

Reverse Coherent Demodulation

Power Control Measurement

Base station enhances the received

performance and increases the capacity

by means of coherent demodulation of

the Reverse Pilot Channel.

CDMA Air Interface

Page 67: Intro to Telecom and CDMA2000 Principle

Reverse ChannelsReverse Channels

Fundamental Channel:

Fundamental Channel is used for the transmission of user

information to the base station during a call, and can be used to

transmit defaulted voice services as an independent Traffic

Channel.

Dedicated Control Channel The Dedicated Control Channel is used for the transmission of

user and signaling information to a base station during a call.

Supplemental Channel/Supplemental Code Channel These channels are used for the transmission of user information,

mainly data services, to the MS. The Reverse Traffic Channel

contains up to two supplemental channels and up to seven

supplemental code channels.

CDMA Air Interface

Page 68: Intro to Telecom and CDMA2000 Principle

Reverse Radio Configuration (RC)Reverse Radio Configuration (RC)

RC: Radio Configuration RC1~RC2:IS-95A/B

RC3~RC4:CDMA2000 1X

RC5~RC6: CDMA2000 3x

RadioConfiguration

SpreadingRate

Max Data Rate*(kbps)

Effective FECCode Rate

OTDAllowed

FEC Encoding Modulation

1** 1 9.6 1/3 No Conv 64-ary ortho 2** 1 14.4 1/2 No Conv 64-ary ortho

3 1 153.6 1/4 Yes Conv or Turbo BPSK(307.2) (1/2)

4 1 230.4 3.8 Yes Conv or Turbo BPSK5 3 153.6 1/4 Yes Conv or Turbo BPSK

(614.4) (1/3)6 3 460.8 1/4 Yes Conv or Turbo BPSK

(1036.8) (1/2)

** Same as IS95

CDMA Air Interface

Page 69: Intro to Telecom and CDMA2000 Principle

RC 1

RC 2

RC 3

RC 4

RC 5

RC 1

RC 2

RC 3

RC 4

RC 5

RC 3

RC 4

RC 4

RC 3

F-FCH RCs

R-DCCH/SCH RCsF-DCCH/SCH RCs

R-FCH RCs

RC Combination RegulationRC Combination Regulation

RC1 and RC2 corresponds

respectively to rate set 1 and rate set

2 in IS- 95A/B system.

CDMA2000 Forward RC: RC1~RC5

Reverse RC: RC1~RC4

Rules: Forward RC1, Reverse RC1

Forward RC2, Reverse RC2

Forward RC3 or RC4,Reverse RC3

Forward RC5, Reverse RC4

CDMA Air Interface

Page 70: Intro to Telecom and CDMA2000 Principle

Course ContentsCourse Contents

Chapter 1 Introduction

Chapter 2 CDMA Techniques & Technologies

Chapter 3 CDMA Air Interface

Chapter 4 CDMA Core Network

Chapter 5 CDMA Number Planning

Page 71: Intro to Telecom and CDMA2000 Principle

A typical CDMA Network A typical CDMA Network

MS BS MSC

HLRAC

EIR

VLR

PSTN

ISDN

MC

Um A

BC

D

E

H

Ai

Di

MSC

F

VLR

MCSMESME

GN

MMM

Q

SCPSCP SSP

Ai

T1T8

IP HLR IP ISDNDi

T2T3T5

T9

CDMA Core Network

Page 72: Intro to Telecom and CDMA2000 Principle

CDMA Interfaces

CDMA Interfaces

MSC: Mobile-service Switching Center BSC: Base Station ControllerMC: Short Message Center HLR: Home Location RegisterBTS: Base Transceiver Station VM: Voice MailboxVLR: Visitor Location Register OMC: Operation & Maintenance Center AC: Authentication Center SCP: Service Control Point

MSC: Mobile-service Switching Center BSC: Base Station ControllerMC: Short Message Center HLR: Home Location RegisterBTS: Base Transceiver Station VM: Voice MailboxVLR: Visitor Location Register OMC: Operation & Maintenance Center AC: Authentication Center SCP: Service Control Point

Other MSCs

MC/VM

MSC/SSP/VLR

OMC

HLR/AC

SDH

GMSC/SSP

SCP

STP

IOS4.0

SS7

IS-41

IS-41

IS-41

IS-41

Mobile Customer Service Center

SS7

TCP/IP

SS7IS-41

BTS

BTS

BSC

MS

IS95----CDMA2000

INTERNET

Other PLMNs

PSTN/ISDN

CDMA Core Network

Page 73: Intro to Telecom and CDMA2000 Principle

Network Interface Network Interface

MSC/VLR GMSC

HLR/AuC

PDSN

PSTN

GPRS IP骨干网

SS7

SCPBSS

HA

A1/A2

BSSAP

SCCP

MTP

Physical layer

IP backbon

e network

A10/A11

A11 signaling

UDP

IP

Link layer

Physical layer

A10 service

GRE

IP

Link layer

Physical layer

CN

CDMA Core Network

Page 74: Intro to Telecom and CDMA2000 Principle

CDMA ServicesCDMA Services

Businesses, enterprises•Mobile virtual private network•Mobile high-speed network access•Advertising services•Free phone

Family•Familiarity number•Life & amusement

Schools, groups•Universal account number•Sectorized and time-shared charge•Broadcast news

Individuals•Individualized services•Privacy

CDMA Core Network

Page 75: Intro to Telecom and CDMA2000 Principle

CDMA Feature Services---Example 1CDMA Feature Services---Example 1

Where is my mobile phone? It is lucky to

have Ruyi lock!

Ruyi lock

Features: a mobile phone user can dial the

access code and input the PIN code to

lock/unlock his mobile phone by using any

fixed telephone instead of registering and

paying at a business hall.

Why can’t I make a call the moment I picked it up?

CDMA Core Network

Page 76: Intro to Telecom and CDMA2000 Principle

CDMA Feature Services---Example 2CDMA Feature Services---Example 2

FOLLOW ME

Features: a user can activate call forwarding

of his/her MS from any phone to ensure that

any incoming call of a mobile phone user will

not be lost.

You can register for a forwarding service on

your own

I forgot to bring my mobile phone, but I will have an important customer to meet this afternoon. What should I do?

CDMA Core Network

Page 77: Intro to Telecom and CDMA2000 Principle

CDMA Feature Services---Example 3CDMA Feature Services---Example 3

Does that guy still bother you recently?

He can no longer reach me!

Why? Ask me to input a password?

Friendshipcom

Features: After a called user subscribes for t

his service, the system requires password to

caller. A call is accomplished only if the pass

word is correct. Otherwise, the call will be reje

cted or transferred.

CDMA Core Network

Page 78: Intro to Telecom and CDMA2000 Principle

CDMA Feature Services---Example 4CDMA Feature Services---Example 4

Intra-group user

LOOK FOR service

Feature 1: When a user makes a call to an intra-group user, the

terminals of all intra-group users ring in-turn or simultaneously

until there is a reply.

CDMA Core Network

Page 79: Intro to Telecom and CDMA2000 Principle

CDMA2000---Data Services

0

32

64

9.6

128

144

384

2,000 Video StreamingVideo Streaming

VoiceVoice

Text Text MessagingMessaging

Still ImagingStill Imaging

Audio StreamingAudio Streaming

Electronic newspaper

High-quality videoconference

Telephone (Voice)

Voice Mail

E-MailFax

Electronic book

Sports, news and weather report on

demand

Singing room

Low-quality videoconference

JPEG Still Photos

Mobile Radio

Video Surveillance,Video Mail, Travel

Image

Data

Weather, transportation, news, sports and securities

Mobile TV

E-commerce

RemoteMedical Service

Da

ta r

ate

in

Kb

ps

Da

ta r

ate

in

Kb

ps

CDMA Core Network

Page 80: Intro to Telecom and CDMA2000 Principle

3GPP2 uses the following 3 standards for MS location:

Locating Services Locating Services

GPS-aided measurement

Accuracy: suburbs---10m.

City zone---30~70m.

Indoor --unable to locate

Response time: 3~10s

Measurement of base station pilot phase

Accuracy: 50~200m

Response time: 3~6s

Locating of a cell ID

Accuracy: depends on the size of a cell

Response time: within 3s

CDMA Core Network

Page 81: Intro to Telecom and CDMA2000 Principle

110! Bandit!

The system transfers the alarm to the nearest alarm

processing center based on the location.

An emergency button can be set on a user’s mobile phone to

so that an alarm can be reported without any conversation or

delay.

Locating ServicesLocating ServicesCDMA Core Network

Page 82: Intro to Telecom and CDMA2000 Principle

PSTNCDMA/

INTERNET

Users who subscribe for toll services

Original toll route

Toll route after subscriptionMSC/GMSC

HLR

Operators who subscribe for toll services

Help mobile operators to absorb large quantities of toll

services

Users subscribe to select toll operators to ensure quality

of service.

Enable users to save toll call charge (premium strategy)

Make an IP toll call without dialing a preamble

Equal Access of Toll CallsEqual Access of Toll Calls

CDMA Core Network

Page 83: Intro to Telecom and CDMA2000 Principle

Course ContentsCourse Contents

Chapter 1 Introduction

Chapter 2 CDMA Techniques & Technologies

Chapter 3 CDMA Air Interface

Chapter 4 CDMA Core Network

Chapter 5 CDMA Number Planning

Page 84: Intro to Telecom and CDMA2000 Principle

Definition of Coverage Areas

Definition of Coverage Areas

Location area

MSC area

PLMN area

Service area

Sectorarea

CDMA Number Planning

Cell area

Page 85: Intro to Telecom and CDMA2000 Principle

Parameters InvolvedParameters Involved

In a CDMA system, the following parameters are

defined to identify a user and his location:

MIN/IMSI

MDN

ESN

TLDN

SID/NID

LAI

GCI

SIN

SSN

CDMA Number Planning

Page 86: Intro to Telecom and CDMA2000 Principle

MIN/IMSIMIN/IMSI

Mobile subscriber identity/international mobile subscriber identity

For example, 0907550001/460030907550001

Not more than 15 digits

3 digits 2 digits

IMSI

MCC MNC MSIN

NMSI

CDMA Number Planning

Page 87: Intro to Telecom and CDMA2000 Principle

MDNMDN

CC + MAC + H 0H 1H 2H 3 + ABCD

International mobile subscriber DN

National valid mobile subscriber number

Mobile directory number

For example, 8613307550001

CDMA Number Planning

Page 88: Intro to Telecom and CDMA2000 Principle

ESNESN

A unique Electronic Serial Number (ESN) is used to identify single

MS. An ESN includes 32 bits and has the following structure:

31......24 23......18 17......0 bit

Manufacturer’s number retained equipment SN

For example, FD 03 78 0A (the 10th Motorola 378 mobile phone)

The equipment serial number is allocated by a manufacturer.

CDMA Number Planning

Page 89: Intro to Telecom and CDMA2000 Principle

TLDNTLDN

+CC MAC H0H 1H2 ABC+ ++44

Temporary local directory number

For example, 8613344755001

CDMA Number Planning

Page 90: Intro to Telecom and CDMA2000 Principle

SID/NIDSID/NID

MSCID (Exchange Identity)

= System Identity (SID) + Exchange number (SWIN)

is used to represent a certain set of equipment in an NSS network. For example,

Unicom CDMA Shenzhen MSC is labeled as 3755+01

CDMA Number Planning

Page 91: Intro to Telecom and CDMA2000 Principle

Location Area Identity (LAI)Location Area Identity (LAI)

PAGING message is broadcast within a local area, the size of

which depends on traffic, paging bearer capability, signaling flow ,

etc.

Format: MCC+MNC+LAC MCC: Mobile Country Code, 3 digits. For example, China is 460.

MNC: Mobile Network Code, 2 digits. For example, the MNC of

Unicom is 03.

LAC: Location Area Code, a 2-byte-long hexadecimal BCD code.

0000 cannot be used with FFFE.

For example, 460030100

CDMA Number Planning

Page 92: Intro to Telecom and CDMA2000 Principle

Global Cell Identity (GCI)Global Cell Identity (GCI)

The unique ID of a cell in PLMN

Format: LAI+CI

CI: Cell Identity, a 2-byte-long hexadecimal BCD code,

pre defined by the engineering department. The first 3

digits and the last digit represent the base station

number and the sector number respectively. For an

omni-directional site, the last digit of CI is 0.

For example, 4600301001230 shows base station number

123 contains an omni-directional site

CDMA Number Planning

Page 93: Intro to Telecom and CDMA2000 Principle

Sender Identification Number (SIN)Sender Identification Number (SIN)

MSC number

The MSC number stipulated by Unicom is 460 + 03 + 09 +

H0H1H2H3 + 1000.

HLR number

The HLR number stipulated by Unicom is 460 + 03 + 09 +

H0H1H2H3 + 0000.

SMC number

The SMC number stipulated by Unicom is 460 + 03 + 09 +

H0H1H2H3 + 2000.

SCP number

The SCP number stipulated by Unicom is 460 + 03 + 09 +

H0H1H2H3 + 3000.

CDMA Number Planning

Page 94: Intro to Telecom and CDMA2000 Principle

Sub-System Number (SSNSub-System Number (SSN

SSN of MSC: 8

SSN of VLR: 7

SSN of HLR: 6

SSN of AC: 10

SSN of SMC: EE

SSN of SCP: EF

SSN of A interface: FE/FC

SSN of SCCP management: 1

CDMA Number Planning

Page 95: Intro to Telecom and CDMA2000 Principle

Voice Channel RoutingVoice Channel Routing

TMSC1

TMSC2

MSC

TMSC1

MSC

TSI international office

CDMA Number Planning

Page 96: Intro to Telecom and CDMA2000 Principle

Signaling RouteSignaling Route

Level 1

Level 2

Level 3

HSTP&LSTP

SP

CDMA Number Planning

Page 97: Intro to Telecom and CDMA2000 Principle

Example of Signaling NetworkExample of Signaling Network

Route from an LSTP to the LSTP not located in this macro cell

HLR in Chongqin to MSC in Fujian (two LSTPs

respectively at the transmit end and receive end)

H1 in Chengdu

H1 in Shanghai

H2 in Chongqin

H2 in Shanghai

L1 in Chongqin

L2 in Chongqin

L1 in Fuzhou

L2 in Fuzhou

HLR in Chongqin

MSC in Fuzhou

CDMA Number Planning

Page 98: Intro to Telecom and CDMA2000 Principle

Interconnection of CDMA with PSTNInterconnection of CDMA with PSTN

Mobile telephone network

Tm

DC2

DC1

LS

MSC

MS

BTS

BSC

TMSC2

Primary ring of a local network

PSTN

Tollnetwork

Localnetwork

TMSC1

Meshinterconnection

Mesh interconnection

TMSC1

MSC

BTS

BSC

TMSC2

Primary ring of a local network

Tm

DC2

HSTP

LSTP

SP

LSTP

HSTP HSTP

LSTP LSTP

SP SP

SP

DC1

LS

MS

PSTN

CDMA Number Planning

Page 99: Intro to Telecom and CDMA2000 Principle

ReviewReview

Chips rate: 1.2288Mcps

IS-95A/B is a subset, RC1/RC2

Apply the coherent demodulation to the reverse pilot

channel

Forward transmit diversity: OTD and STS

Forward quick power control at 800HZ rate

Improve the standby time by introducing the quick paging

channel.

Variable frames: 5ms, 20ms, 40ms and 80ms

Introduce TURBO code into channel encoding

The maximum rate of a physical layer is up to 307.2K

CDMA Technology

Page 100: Intro to Telecom and CDMA2000 Principle

Development of CDMA Standards in ChinaDevelopment of CDMA Standards in China

CDMA standards currently adopted in China are mainly

based on the USA standards with few alterations. For

example, in USA the emphasis is put on the dual service

support i.e. CDMA and AMPS compatibility, while in China

there is no such requirement. Therefore, the settings of

frequency and basic channels, IMSI and others parameters

need to be modified. Likewise, there is also the need to

modify network interface IS-41 series of standards.

Page 101: Intro to Telecom and CDMA2000 Principle

Case study: China Unicom Network Case study: China Unicom Network

In China Unicom CDMA project, phase 1, a narrow-band CDMA

network, named IS-95B (enhanced IS-95) is being constructed.

With total capacity is 15,000,000, subscribers handling, covering

over 200 cities.

Currently, both nationwide and international roaming tests have

conducted successfully with the CDMA networks of HongKong,

South Korea and Japan via the TSI international gateway bureau.

Besides, a CDMA intelligent network will be constructed to

provide intelligent value-added services like Pre-Paid Charging

(PPC) and Virtual Private Network (VPN) etc.

The whole CDMA20001X network was launched in air in the

second half of 2002.

Page 102: Intro to Telecom and CDMA2000 Principle

Why CDMA2000? Why CDMA2000?

Increase the system capacity Forward quick power control

Forward transmit diversity: OTD,STS

Coherent modulation applied on the pilot channel.(about

3dB)

The introduction to Turbo code

The stronger ability to resist interference

The improved error-correcting encoding

(applying Turbo code in medium/high rate

data transmission)

Page 103: Intro to Telecom and CDMA2000 Principle

Why CDMA2000?Why CDMA2000?

Support high rate SCH, with the maximum rate

of a single channel being up to 307.2kbps.

Improve the standby time Use the quick paging channel

Forward compatibility Radio-frequency part

Baseband part, such as RC

Page 104: Intro to Telecom and CDMA2000 Principle

SummarySummary

Brief Development History of Mobile Communication

Analog--digital--code division Objectives of 3G and comparison of 3 systems

Technical features of CDMA Key technologies: power control, soft handoff,RAKE receiver

and cell breath Other technologies: source coding, channel coding,

interleaving, scrambling, spreading and modulation Channel structure: pilot, synchronization, paging, access and

service

Technical features of CDMA2000 1X Walsh and Turbo codes

Page 105: Intro to Telecom and CDMA2000 Principle

QuestionsQuestions

What power control modes are there in CDMA2000

system and how are they implemented?

Describe the soft handoff process?

Describe the process and functions of cell breath?

Describe the implementation process of service

channels (forward and reverse)?

Describe the technical features of CDMA2000?

Describe the initialization process of a mobile

phone?

What are the functions of a long code, short code

and Walsh code in CDMA system?

Page 106: Intro to Telecom and CDMA2000 Principle