CDMA for Trainee's from HUWAEI

Internal

ORA010002 CDMA2000 1x Principle ISSUE 5.0

HUAWEI TECHNOLOGIES CO., LTD.

www.huawei.com

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Upon completion of this course, you will be able to: > Describe > List

the development of mobile system

the structure of CDMA2000 1X network

> State

the principle of CDMA2000 1X

> State

the key technology of CDMA2000 1X

> Describe

the air interface of CDMA2000 1X

> Describe

the numbers in CDMA2000 1X


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Page 1

Upon completion of this course, you will be able to: > Describe > List

the development of mobile system

the structure of CDMA2000 1X network

> State

the principle of CDMA2000 1X

> State

the key technology of CDMA2000 1X

> Describe

the air interface of CDMA2000 1X

> Describe

the numbers in CDMA2000 1X


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Page 1

C hapter Introduct uctio ion n Chapter Cha pter 1 Introd uction C hapter P rincip cip le of Sprea preadin din g Chapter Cha pter 2 Prin Princi ple preading Chapter 3 Techn T echnol olog ogy y of o f CDMA20 CDM A2000 00 Techno echno logy lo gy CDMA2 CD MA200 000 0 Chapter 4 Physi cal Laye L ayerr of o f CD CDMA2 MA200 000 0 Layer C hapter g Chapter Cha pter 5 Number Number Numb er Plannin Planning Planni ng


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Page 2

C hapter ntrodu ntr odu ction cti on Chapter Cha pter 1 IIntrod Introduct uctio ion n 1.1 Deve 1.1 D evelop lopment ment obi le Comm Communi unication Developm De velopment ent of M Mobi Mobile uni cations cation s 1.2 Develop 1.2 D evelopment ment CDMA MA System Deve evelo lopm pment ent of CD 1.3 CDMA 2000 Network Structure


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Page 3

Transmission Techniques Traffic channels: different users are assigned uniq ue code and transmitt ed over th e same frequency band, for example, WCDMA and CDMA2000

CDMA Power

T i m e

c y e n u q F r e

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

Power

T i m e

y n c u e q F r e

FDMA

Power

T i m e


y n c e u q F r e

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Traffic channels: different frequency b ands are alloc ated to different users,for example, AMPS and TACS

Page 4

Development of Mobile Communications 1st Generation 1980s (analog)

2nd Generation 1990s (digital)

3rd Generation current (digital)

GSM

UMTS WCDMA

AMPS TACS

An alo g to Dig it al

NMT

CDMA IS95

Voic e to Br oadban d

TDMA IS-136

TDSCDMA

Others PDC

z

3G provides: >

Complete integrated service solutions

>

High bandwidth

>

Unified air interface

>

Best spectral efficiency.


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CDMA 2000

Page 5

Difference of 3G Standards CDMA2000 3GPP2 FDD mode

3GPP =Third Generation Partn ership Project CWTS = China Wireless Telecomm Standard FDD = Frequency Divisi on Dupl ex TD-SCDMA = Time Divi sio n Sync hrono us CDMA

WCDMA 3GPP

TD-SCDMA

3G system

CWTS

FDD mode


TDD mode

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Page 6

Chapter 1 Introdu ction Introduction 1.1 Development of Mobi le Communications Mobile Communi cations 1.2 Development of CDMA System 1.3 CDMA 2000 Network Structure


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Development of CDMA System CDMA2000 3x

IS95A 9.6kbps

1995

IS95B 115.2kbps

1998

CDMA2000 1x 307.2kbps Heavier voic e service capacity

CDMA2000 1x EV

Î

Longer period of standby time

1x EV-DO

Î

1x EV-DV

2000

2003

z

Higher spectrum efficiency and network capacity

z

Higher packet data rate and more diversified services

z

Smooth transit to 3G

Project Evolution process of CDMA2000 EV: phase 1: 1XEV-DO ( Data Only / Data Optimized ) Providing the support for packet data services alone instead of real-time voice services. phase 2: 1XEV-DV ( Data and Voice ) Providing non-real time packet data services and real-time voice services


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Page 8

- 153.6 kbps

Chapter 1 Introdu ction Introduction 1.1 Development of Mobi le Communications Mobile Communi cations 1.2 Development of CDMA System 1.3 CDMA 2000 Network Structure


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CDMA 2000 Network Structure


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Questions z

How many standards are there in 3G?

z

How to understand the three techniques of multi-access?

z

How many network elements are there in CDMA2000 1X network?


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Chapter 1 Introduction Chapter 2 Princip le of Spreadin g Princi ple Spreading Chapter 3 Technology Techno logy of CDMA2000 Chapter 4 Physi cal Layer of CDMA2000 Chapter 5 Number Plannin g Planning


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Chapter 2 Principle Prin ciple of Spreading Spreadin g 2.1 Basic Conception 2.2 Communi cation Model Communication


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Page 13

Frequency Allocation in CDMA2000 (Extra Slide) z

Band Class 0 (800 MHz) Transmit Frequency Band (MHz) Block Designator

CDMA Channel

CDMA

Validity

Channel

Mobile Station

Base Statio n

Number

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

The transmit frequency poi nt for Base Station is computed by: F = 870+N*0.03

;

N = CDMA Channel Number

CDMA: 1.25 M/30k = 41 channels

N= 283, 242, 201, 160, 119, 78, 37

GSM: 1.25M/200k = 6 channels x 8 TS = 48 channels HUAWEI TECHNOLOGIES CO., LTD.

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Page 14

Frequency Allocation in CDMA2000 (Extra Slide) z

Band Class 5 (1800 MHz) Transmit Frequency Band (MHz) CDMA

CDMA

Channel

Channel

Validity

Number

A(15MHz)

Valid

D(5MHz)

Block

Mobile Station

Base Statio n

25-275

1851.250-1863.750

1931.250-1943.750

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

Designator

The transmit frequency p oint for Base Station is computed by: F = 1930 + N*0.05

;


N = CDMA Channel Number All rights reserved

Page 15

Direct Spread (DS) Receiving

Transmission Wideband sign al Slow Information Sent

Slow inf ormation Recovered

Fast s preading sequence

Fast s preading sequence

z

Direct –Sequence Spread spectrum system mixes the input data with a fast sequence and transmits a wideband signal.

z

The spreading sequence is independently regenerated at the receiver and mixed with the incoming wideband signal to recover the original information. In CDMA 1X,Chip rate = 1.228 Mcp s and BW = 1.25 MHz


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Page 16

Direct Spread (DS) Information s ignal bit

Spread sequence

Spread sign al

Spread sequence

Recover sign al

Spread & De-spread HUAWEI TECHNOLOGIES CO., LTD.

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Page 17

Spectrum-domain Analysis Power spectrum o f information signal(narrow band) P( )

Spread

Power spectrum o f spread signal(broad band) P( )

P( ) Add

P( )

P( )

De-spread

P( )

integral/filtering

Recover si gnal’s power spectrum (narro w band)

Mixed sig nal’s pow er spectrum(broad band and narrow band)


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Mixed sign al’s power spectrum(broad band and broad band) Page 18

Correlation => measure of similarity of any two arbitrary signals

Correlation 100% so the functions are parallel

(a) 0 XOR 0 = 0 0 XOR 1 = 1 1 XOR 0 = 1 1 XOR 1 = 0

Correlation 0% so the functions are orthogonal

(b) HUAWEI TECHNOLOGIES CO., LTD.

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Page 19

Orthogonal Function Sequence 1#

Sequence 2#

1# 2 #

Output of integral circuit Orthogonal function s have zero correlation. Two binary sequences are orthogonal if their “XOR” output contains equal number of 1’s and 0’s. Actually CDMA system need orthogonal sequences to overcome the self-interferences in the system because all the users share the same frequency simultaneously. HUAWEI TECHNOLOGIES CO., LTD.

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Page 20

Multiple Access Information bit 1#

Sequence 1# Spread Signal 1#

Information bit 2#

Sequence 2#

Spread Signal 2#

Mixed Signal 1+2

Code Division Multiple Address Principle HUAWEI TECHNOLOGIES CO., LTD.

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Page 21

Multiple Access Mixed Signal

Spread Sequence 1#

De-spread Signal

Output o f Judgement circuit

1st receiver resume process HUAWEI TECHNOLOGIES CO., LTD.

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Page 22

Multiple Access Mixed Signal

Spread Sequence 2#

De-spr De -sprea ead d Signal

Output of Judgement circuit

2nd receiver resume process HUAWEI TECHNOLOGIES CO., LTD.

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Page 23

Multiple Access with Orthogonal Sequence z

User# 1’s information: 10111001 Spread Signal for User#1: 00111100

z

User# 2’s information: 11001010 Spread Signal for User#2: 01101001

Given the rate of spread signal is 8 times of information rate. Show that User#1’s information can be recovered if it’s spread with its spread signal after multiple access


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Page 24

C hapter Princip preadin ding Chapter Cha pter 2 Prin rin ciple cip le of Sprea din g 2.1 Basic Conception 2.1 Conc eption 2.2 Comm 2.2 Communi uni cation M odell unication Model Mode


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Page 25

Communication Model 1 0 0 1 0 1 1 0 0 1 1 1 0 0 0 1 1 0 0 1

1 0 1 1

1 0 1

Channel Coding

Source coding

Spread

Scrambling

Mo d u l at i o n

RF t r an s i t

Reverse Forward Bit

Sy m b o l

Ch i p

1 1 0 1

Source Decoding

0 1 1

Channel Decoding


De-Sp r ead

Unscrambling

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Dem o d u l at i o n

Page 26

RF r ec ei v e

Source Coding

z

There are 3 types of source coding in CDMA 2000 system: > 8K

QCELP

> 13K

- - >8k sample values with 8-bit quantization coding => a wired system has the rate of 64k.

QCELP

8K = 9.6, 4.8, 2.4, 1.2 kbp s

> EVRC z

13K = 14.4, 7.2, 3.6, 1.8 kb ps

Characteristic: > Support

EVRC= 9.6, 2.4, 1.2 kbp s

voice activity

QCELP: Qualcomm Code Excited Linear Predictive coder EVRC: Enhanced Variable Rate Code HUAWEI TECHNOLOGIES CO., LTD.

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Page 27

Channel Coding Channel Coding: Convolution z

Convolution code or TURBO code is used in channel encoding

z

Encoding efficiency= (total input bits  total output symbols) 00110001 Bi t

00001011

Register

M U X

Symbol 0000110100101011

00100111


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Page 28

Channel Coding Channel Coding: Interleaving Transmission direction Input:

1 2 3 4 5 6 7 8

yyyyyyyyyyyyy

1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8

Write by row

Read by column

Interleaver

Transmission direction Output:

8 8 8 8 8 8 8 8

yyyyyyyyyyyyy


3 3 3 3 3 3 3 3 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1

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Page 29

Channel Coding 1

0

1

1

1

1

1

0

1 1 1 0

Without ch annel codi ng, receiver can’t corr ect any errors

1

0

1

1

1 1 1 0 10 1 1 0 11 1

1 1 1 0 0 0 1 1 1 11 1 1 Source

0

1

1

0

1

1

1011

1 1 1 0 1 1 0 0 1 11 1

1

111 000 111 111

1

1

0

1

1101

After conv olu tio n, recei ver can cor rect error s.

1 0 1 1

But r ecovery capability is restricted by encoding complexity.

1 0 1 1 1 1 1 0 0 0 1 1 1 11 1 1 1 0 1

1011 0100 1011 1 1 0 1

11 11 0 0 11

10 11 1011 1 0 11

01 01 1 0 01

101 010 101 101

1 0 1 1

Through t he interleaving , the cons ecutive error codes can be cor rected HUAWEI TECHNOLOGIES CO., LTD.

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Page 30

Scrambling and Spreading Scrambling = the processing of making signals randomization. M-sequence performs this function. Spreading = the processing that can widen the spectrum. Walsh Code performs this function.

z

z

M Sequence for scrambling > Long

Code

> Short

Code

Walsh Code for spreading


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Page 31

Scrambling and Spreading M Sequence

0 1

0 1

1 0

Out

z

Two points are important here: >

Maximum number of shift register (N)

>

Mask

z

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

z

Only sequence offset is change when the mask is changed

z

PN stands for Pseudorandom Noise sequence


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Page 32

Scrambling and Spreading Long Code Long code is used for scrambling on the Forward channel and spreading on the Reverse channel.

z

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

z

The functions of a long code: > Scramble

the forward CDMA channel

> Control

the insertion of power control bit

> Spread

the information on the reverse CDMA channel to identify

the mobile stations


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Page 33

Scrambling and Spreading Short Code z

Short code is a PN sequence with period of 215 chips >

Sequence with different time offset is used to distinguish different sectors

PNc PNb

PNa

z

Minimum PN sequence offset used is 64 chips, that is, 512 PN offsets are available to identify the CDMA sectors (215/64=512).


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Page 34

Scrambling and Spreading Walsh Code Walsh Code is one kind o f orth ogonal code.

Walsh code W2n=

W n Wn W n Wn

Note: W0 = Pilot Ch.

W1-W7 = Paging Ch

W1=0 W2=

0

0

0

1

0 0 W4 = 0 0

0 1 0 1

0 0 0 1 1 1 1 0

W32 = Synch Ch z

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

z

A Walsh can be presented by Wim where ith (row) is the position and m is the order. For example, W24 means 0101 code in W4 matrix

z

Walsh code is used to spread the forward traffic channel


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Page 35

MS: Which BTS should I listen?

BTS A

P N 4

BTS B 8 0 1 N P

5 2 P N

BTS C

A PN sequence (short code) with period of 215 bits , is used with 64bits off set. That is 512 total PN available to id entif y the 512 sectors/BTSs.


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Page 36

MS-B: Which is my signal? 0000000…. A 0101010…

B

0000111…

C MS-C

MS-H 0

0101010…

MS-G

MS-B MS-A MS-F MS-D MS-E

Each MS has un iqu e Walsh c ode. Normally CDMA2000 uses 64 arr ay Walsh codes


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Page 37

BTS: Who is my Mr. D?

MS-C

MS-H MS-B

MS-G MS-A MS-F MS-D MS-E

A PN seq uen ce (lo ng cod e) wi th per io d of 242-1 bits which is used to Spread the info rmation on t he reverse CDMA channel and identif y th e MS. A un ique ESN is used as mask to achieve uniq ue starting poin t


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Page 38

Modulation

Q P S K

H P S K / O Q P S K


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Page 39

Questions z

How to understand spreading and multi access?

z

What is the main function of each step in communication model ?

z

How to understand the three types of codes in CDMA2000 1X ?

z

Why do we say CDMA system is self interference system ?


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Page 41

Technology Of CDMA2000

z

Power control

z

Rake Receiver

z

Soft handoff


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Page 42

Power Control Far/near problem exists in wireless system

no power control

after power contro l


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Page 43

Power Control CDMA is a self -interference system

no power control

after power cont rol


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Page 44

Power Control Classification Of Power Control z

z

According to the directions, power control can be divided into: > Reverse

power control

> Forward

power control

According to the types, power control can be divided into: > Reverse

power control

--> used for making the link while originating a call and reacting to path-loss fluctuation.

− Reverse open loop power control

− Reverse closed loop power control > Forward

power control

- -> aims at reducing the interference on fwd link

− Measurement report power control IS95A: fwd pwr ctrl is based on MR. − EIB power control

IS95B: system can support EIB pwr ctrl

− Fast power control

CDMA2000: the highest priority is fast pwr ctrl

Note:

EIB = Erasure Indicator Bit


FER= Frame Error Rate All rights reserved

Page 45

Power Control Reverse Open Loop Power Control

BTS

Reverse Open Lo op Power Control

Mobile

BTS

BTS

Transmitting Power

z

z

The mobile transmission power 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.


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Page 46

Power Control Reverse Closed Loop Power Control Both fwd and rev link traffic channel frames are 20 ms in duration (16 segments or 16TS).

Power Control Bi t PCB has a response time of 1.25ms on T-CH

Every frame = 16TS

FER Value

Eb /Nt Value

BSC BTS Change in Eb /Nt Value

(to keep MS close to Eb/Nt setpoint)

Inner Loop Power Control

(to adjust target Eb/Nt at BTS

Outer Loop Power Control Note that since the rate of PCB transmission is 800bps, a PCB is sent once every 1/800 second or 1.25 ms. HUAWEI TECHNOLOGIES CO., LTD.

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Page 47

Power Control Fast Forward Power Control Power Control Bit

Eb/Nt

Eb/Nt Comparator

FER

FER Measurement

MS

BTS HUAWEI TECHNOLOGIES CO., LTD.

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Page 48

RAKE Receiver


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Page 49

RAKE Receiver

Recover sign al from s ingle path and adjust it’s time delay

90

Combiner

Correlator 1

90

0 Correlator 2 output Receive set

RAKE receiver c an miti gates

0

Correlator 3

mult i-path fading and enhance the receive performance of the system. Searcher cor relator


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Calcul ate the time d elay and signal strength

Page 50

Soft Handoff Pilot Sets Searcher correlator

All pilot that can be detected by searcher correlator is classify to four pilot set.

Active Set

An active pilot is a pilot whose paging or traffic channels are actually being monitored or used.

Candidate Set

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

Neighbor Set

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

Remaining Set HUAWEI TECHNOLOGIES CO., LTD.

Other pilot

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Page 51

Soft Handoff Soft Handoff And Softer Handoff z

Soft/softer handoff means MS can keep traffic channel with two or more sectors. > Soft

handoff—involves traffic channel from more than one BTS and Multipath combination in the BSC.

> Softer

handoff—involves traffic channel from two or more sectors of one BTS and Multi-path combination in the BTS.


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Page 52

Soft Handoff Important Parameters of Soft handoff Sector A

Sector B

Ec /Io

Add Threshold (T_ADD) Guard Time(T-TDROP)

DropThreshold (T_DROP)

Soft Handoff Region Time 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. HUAWEI TECHNOLOGIES CO., LTD.

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Page 53

Soft Handoff Dynamic Soft Handoff Pilot strength

P2

P1

T_ADD

T_DRO P

T_TDROP

1

Neighbor Set

2

3

Candidate Set

4

T_TDROP

5

6

7

TIME

8

Ac ti ve Set Ac ti ve Set

Candidate Set

Neighbor Set

1. P2>T_ADD 2. P2> [(SOFT_SLOPE/8) * 10 * log10(PS1) + ADD_INTERCEPT/2]. 4. P1< [(SOFT_SLOPE/8) * 10 * log 10(PS2) +DROP_INTERCEPT/2] 7. P1
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Page 54

Questions z

Why CDMA system need power control ?

z

What is the function of the RAKE receiver ?

z

What is the difference between hard handoff and soft handoff ?

z

Why can CDMA system support soft handoff ?


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Page 56

Physical Layer Of IS95

Comparing with IS-95A, there is another channel named SCCH which supports data traffic whose maximum rate is 115.2kbps

SCCH = Supplemental Code Channel HUAWEI TECHNOLOGIES CO., LTD.

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Page 57

Physical Layer Of IS95 Forward Link: Pilot Channel W064 Pilot channel (all-zeros)

Not only does Pilot sequence help in initial acquisition when MS powers up, but also ensures rapid detection of handoff candidates. z

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

z

BTS transmits the pilot channel continuously

z

The Pilot channel carries no data


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Page 58

Physical Layer Of IS95 Forward Link: Sync Channel Code symbol

Sync Ch bits

Convolution encoder

1.2kbps

z

r=1/2,K=9

2.4kbps

symbol repetition

Repetitive code symbol

4.8kbps

W3264

Block interleaving

4.8kbps

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: long code at the time specified in system time − Paging channel rate: P_RAT: 4.8 or 9.6 kbps z

Here note that, sync channel rate is 1200bps


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Page 59

T o Q P S K c o d e r

Synch Channel

Sync Sync channel channel Frame Frame

1bit 1bit

31bits 31bits

SOM SOM

Data Data

Note: Note: SOM SOM == 11 for for first first body body of of Sync Sync Ch. Ch. Message Message SOM SOM == 00 for for all all other other bodi bodies es in in Sych Sych Ch. Ch. message message

96bits 96bits Sync Sync Channel Channel Super-frame Super-frame

Sync Sync Frame#1 Frame#1

Sync Sync Frame#2 Frame#2 80ms 80ms

SOM SOM = = Start Start Of Of Message Message HUAWEI TECHNOLOGIES CO., LTD.

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Page 60

Sync Sync Frame#3 Frame#3

Physical Layer Of IS95 Forward Link: Paging Channel Paging Convolution channel b its

encoder r=1/2,K=9

9.6/4.8 kb ps

Code symbol

Symbol repetition

19.2/9.6Kbps

Block interleaving

19.2kbps

T o Q P S K c o d e r

19.2kbps

19.2kbps

W164 z

The paging channel transmits:

decimator

− System parameters message: PN offset index

1.2288Mcps

− Access parameters: Open Loop power control

Long code PN generator

− Neighbors list: e.g., the neighbors’ pilot PN seq offset index, channel list message

− CDMA channels list message: list of CDMA carriers z

The frame length of a paging channel is 20ms

z

W1 ~ W7 are spared for the Paging Channels spreading


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Paging channel address mask

Page 61

Physical Layer Of IS95 Forward Link: Traffic Channel (FCH And SCCH) Forward traffic channel (172/80/40 or 8.6kbps 16bits/frame) 4.0kbps 2.0kbps 0.8kbps

Ad d frame quality indicator bits(12,10,8,6)

Convolution Ad d 8 Symbol encoder encoded tail repetition 9.6kbps r=1/2,K=9 19.2ksybps bits 4.8kbps 9.6ksybps 2.4kbps 4.8ksybps 1.2kbps 2.4ksybps

19.2kbps

I Ch PN sequence (1.2288 Mcps ) 800 Hz Power control bit s

+

Cos(2pf c t)

Baseband filter

+ I(t)

19.2kbps Block interleaver Repetitive symbol Long code generator

MUX

+ /64

decimator PN 1.2288 Mcps


/24

QPSK Modulation

Walsh code

decimator

+

Baseband filter

Q Ch PN sequenc e (1.2288 Mcps) All rights reserved

Page 62

+ Sin(2pf c t)

Q(t)

used by MS to init iate comm unic ation or respo nd to Paging Channel

Physical Layer Of IS95 Reverse Link: Access Channel 4.4 kbps Ac cess channel (88 bits/frame)

Ad d 8 encoder tail bits

Repetitive symbol

4.8 kbps Convolution 14.4 kbps Symbol encoder repetition Code r=1/3,K=9 symbol

28.8 kbps

Block interleaving

Acces s Chan nel frame => 88 b it s/frame, 20ms Repetitive symbol

I Ch PN sequenc e (1.2288 Mcp s)

28.8 kbps

Frame rate

Orthogonal spreading 4.8 kbp s (307.2kbp s)

PN chip s 1.2288 Mcps Data bur st randomizer

+

Cos(2pf c t)

I(t)

Baseband filter

+

1/2 PN chips Delayed time=406.9ns QPSK Modulation

Walsh co de Long code mask


+

Baseband filter

+

Q(t)

Sin(2pf c t)


Q Ch PN sequ ence (1.2288 Mcps) Page 63 All rights reserved

Physical Layer Of IS95 Reverse Link: Traffic Channel (FCH And SCCH) Reverse tr affic channel 8.6kbps 4.0kbps 2.0kbps 0.8kbps

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

convolution Symbol Ad d 8 encoder repetition encoded tail 9.6kbps r=1/3,K=9 28.8Ksybps bits 4.8kbps 14.4Ksybps 2.4kbps 7.2Ksybps 1.2kbps 3.6Ksybps

I Ch PN sequence (1.2288 Mcps ) Frame rate Orthogonal spreading 4.8 kbps (307.2kbp s) Block interleaver

Data bur st randomizer

PN chip s 1.2288 Mcps

+

Baseband filter

Cos(2pf c t)

I(t)

+

1/2 PN chips Delayed time=406.9ns QPSK Modulation

Walsh co de Long c ode mask


+

Baseband filter

+

Q(t)

Q Ch PN sequenc e (1.2288 Mcp s) Sin(2pf c t) HUAWEI TECHNOLOGIES CO., LTD.

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Page 64

Physical Layer Of CDMA2000

Definition of IS2000’s Channel:


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Page 65

Physical Layer Of CDMA2000

Symbol repetition

Forward Channel: F-QPCH 1.28S

F-PCH ... 2047 0

1

3

4

5

6

7

8

9

10

11

12

13

14

15

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.

In a quick paging channel slot, the mobile always monitors two paging indicators. The two paging indicators either fall in the first 20-ms portion and in the third 20-ms portion, or fall in the second 20-ms portion and in the fourth 20-ms portion.

F-QPCH

A1

B1

A2

B2

1

2

3

4

20ms

20ms


20ms

20ms

1 20ms

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F-PCH 80ms

2

3

4

20ms

20ms

20ms

Page 66

Physical Layer Of CDMA2000 Forward Channel: F-CCCH

FCCCH : transmit specific messages intended for specific mobiles. FBCCH: transmit broadcast system message

20ms frame (9.6kbps) for all mobiles. 172 information bits

12 CRC bits

8 encoders tails bits

16 CRC bits


20ms frame (38.4kbps) 744 information bits There are two additional physical signaling

channels:

FCCCH

10ms frame (38.4kbps)

and

FBCCH to improve the signaling efficiency of the link.

360 information bits

16 CRC bits 8 encoders tails bits

5ms frame (38.4kbps) With QPCH together, F-CCCH shared by many mobiles carries mobile-specific messages . HUAWEI TECHNOLOGIES CO., LTD.

172 information bits 16 CRC bits 8 encoders tails bits All rights reserved

Page 67

Physical Layer Of CDMA2000 Forward Channel: F- DCCH

F-DCCH carries user data that is typically low-rate, such as SMS.

20ms frames (9.6kbps) 12 CRC bits

172 information bits

z


5ms frames (9.6kbps)

F-DCCH is a dedicated signaling channel.

z

F-DCCH can carry user data that is typically low-rate.

24 information bits


All rights reserved

16 CRC bits 8 encoder tails bits Page 68

Physical Layer Of CDMA2000 Forward Channel: F-SCH The dif ferent Walsh cod es corr esponding to di fferent data rates

• 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 W08 =00000000 W04 =0000

64

W48 =00001111

W02 =00

W28 =00110011

W24 =0011

W01 =0

32

W68 =00111100 W18 =01010101

W14 =0101 W58 =01011010

16

( W416 ,W1216) ( W216 ,W1416) ( W616 ,W1416 ) ( W116,W916 ) ( W516 ,W1316 )

W38 =01100110

8 4 2

9600 19200 38400

( W016 ,W816)

76800 153600 307200 614400

Data rate -bps HUAWEI TECHNOLOGIES CO., LTD.

( W316 ,W1116)

W12 =01

1

All rights reserved

W34 =0110

Page 69

W78 =01101001

( W716,W1516 )

Physical Layer Of CDMA2000 Reverse Channel: R- PICH Pilot( all '0's)

Reverse Pilot Channel

MUX

A

Power Contr ol Bi t z

The Function of Reverse Pilot Channel > Initialization > Tracing > Reverse > Power

z

Pilot

Coherent Demodulation

Control Measurement

Base station enhances the received performance and increases the capacity by means of coherent demodulation of the Reverse Pilot Channel.


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Power Control

384 NPN Chips Power Control Group = 1536 NPN Chi ps

N is t he Spr eadin g Rate number

Page 70

Physical Layer Of CDMA2000 Reverse Channel: R- EACH z

The Function of R-EACH > initiate

EACH = Enhance Access Channel which is similar to R-ACH in IS-95 but shorter in duration. EACH needs to transmit a preamble before transmitting the actual R-EACH transmission.

communication with the base station and to respond to

a Paging Channel message > transmit

its access request T preamble

Reverse Pilot Channel

Preamble (All 0s)


R-EACH Data

R-EACH Frame Data

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Page 71

Physical Layer Of CDMA2000 Reverse Channel: R-SCH

R-SCH only carry data, not signaling, that is, RC (Radio Configuration)

R-FCH

R-SCH Bursting data is coming

z

To support data traffic, the R-SCH has two unique characteristics: > only

carry user traffic data and does not carry any signaling traffic

> Should

be set up and torn down rather quickly


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Page 72

RC Combination Regulation Forward Radio Configuration Radio Spreading Max Data Rate* Effective FEC OTD Configuration Rate (kbps) Code Rate Al low ed FEC Encodi ngModul ation 1** 2** 3 4 5 6 7 8 9

1 1 1 1 1 3 3 3 3

9.6 14.4 153.6 307.2 230.4 307.2 614.4 460.8 1036.8

Spreading Rate

Max Data Rate* (kbps)

Effective FEC Code Rate

OTD Al l ow ed

FEC Encoding

Modulation

1** 2** 3

1 1 1

Conv Conv Conv or Turbo

64-ary ortho 64-ary ortho BPSK

1 3

Yes Yes

Conv or Turbo Conv or Turbo

BPSK BPSK

6

3

1/3 1/2 1/4 (1/2) 3.8 1/4 (1/3) 1/4 (1/2)

No No Yes

4 5

9.6 14.4 153.6 (307.2) 230.4 153.6 (614.4) 460.8 (1036.8)

Yes

Conv or Turbo

BPSK

Radio Configuration

1/2 3/4 1/4 1/2 3/8 1/6 1/3 1/4 or 1/3 1/2or 1/3

No No Yes Yes Yes Yes Yes Yes Yes

Conv. Conv Conv and Turbo Conv and Turbo Conv and Turbo Conv and Turbo Conv and Turbo Conv and Turbo Conv and Turbo

Reverse Radio Configuration HUAWEI TECHNOLOGIES CO., LTD.

All rights reserved

Page 73

BPSK BPSK QPSK QPSK QPSK QPSK QPSK QPSK QPSK

RC Combination Regulation z

z

RC1 and RC2 corresponds respectively to rate set 1 and rate set 2 in IS- 95A/B system. CDMA2000 Forward RC: RC1~RC5

R-FCH RCs

RC 1

RC 1

RC 2

RC 2

RC 3 RC 3

Reverse RC: RC1~RC4 z

F-FCH RCs

RC 4 RC 5

RC 4

F-DCCH/SCHRCs

R-DCCH/SCHRCs

Rules: > Forward

RC1, Reverse RC1

> Forward

RC2, Reverse RC2

RC 3

> Forward

RC3 or RC4,Reverse RC3

RC 4

> Forward

RC5, Reverse RC4

RC 5


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RC 3

RC 4

Page 74

Questions z

How many types channels are there in I595 system ? And what are the functions of these channels ?

z

What is the function of F-SCH and R-SCH in CDMA 2000 ?

z

The capacity of CDMA2000 is more than that of IS95, could you give reasons?

z

How do you understand radio configuration ?


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Page 75



All rights reserved

Page 76

Definition of Coverage Areas Service area PLMN area MSC area Location area Cell area Sector area


All rights reserved

Page 77

MIN/IMSI (identity/international mobile subscriber identity ) 15 dig its 3 digits

2 digits

MCC

MNC

MSIN NMSI

IMSI

Mobile subs criber identity/international m obile subs criber identity For example, 0907550001/460030907550001


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Page 78

ESN (Electronic Serial Number ) A unique Electronic Serial Number (ESN) is used to identify single MS. An ESN includes 32 bits and has the following structure:

31

……

Manufacturer’s number

24 23

……

18 17

Retained

……

Equipment SN

For example, FD 03 78 0A (the 10th Motorola 378 mobile phone) The equipment serial number is allocated by a manufacturer.


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Page 79

0

MDN (Mobile directory number) subscr iber number CC

+

MAC

+

H H H H 0

1

2

3

+

ABCD

International mobi le subscr iber DN National valid mo bile subsc riber number

Mobile directory number For exampl e, 8613307550001


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Page 80

TLDN (Temporary local directory number)

CC

+

MAC

+

44

+

H 0H 1H 2

+

Temporary local directory number For exampl e, 8613344755001


All rights reserved

Page 81

ABC

Location Area Identity (LAI) z

PAGING message is broadcast within a local area, the size of which depends on traffic, paging bearer capability, signaling flow , etc.

z

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. z

For example, 460030100


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Page 82

Global Cell Identity (GCI) z

The unique ID of a cell in PLMN

z

Format: LAI+CI

z

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.

z

For example, 4600301001230 shows base station number 123 contains an omni-directional site


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Page 83

SID/NID SID=M NID= t NID= u

SID=L

NID= v

SID=K SID=N

z

In the CDMA2000 1X network, the service area consists of systems and networks that are identified respectively by the system identification (SID) and network identification (NID).

z

The system judges whether the MS is roaming according to the SID and NID.


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Page 84

Number Analyzing

According to MDN, get the IMSI that can be used to query VLR Location

Transfer TLDN to MSC1

Number Analysis 1331688XXXX Find HLR

BSC

HLR

MSC1/VLR With TLDN, connect to MSC2

BTS

13316882234


With IMSI, send paging information to B

MSC2/VLR

According to IMSI, allocate TLDN that will be sent back to HLR

Here is a call for you

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Page 85

BSC

BTS

Questions

z

Please describe the number analyzing in CDMA2000 1X system when a call is happening .


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Page 86

Summary

Summary

z

The difference of three types of multi-access

z

The function of each process in communication mode

z

Three key techniques

z

The physical layer of IS95 and CDMA2000

z

The number analysis during a call


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Page 87

CDMA for Trainee's from HUWAEI

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