WCDMA Principle-20110930-B-V1.0.ppt

5/21/2018 WCDMA Principle-20110930-B-V1.0.ppt

1/98

HUAWEI TECHNOLOGIES CO., LTD. All rights reserved

www.huawei.com

Internal

WCDMA Principle


2/98


Objectives

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

Describe the development of 3G

Outline the advantage of CDMA principle

Characterize code sequence

Outline the fundamentals of RAN

Describe feature of wireless propagation


3/98


Contents

3G Overview

CDMA Principle

WCDMA Network Architecture and protocol structure

WCDMA Wireless Fundamental

Physical Layer Overview Physical Channels

Physical Layer Procedure


4/98


Different Service, Different Technology

AMPS

TACS

NMT

Others

1G 1980sAnalog

GSM

CDMA

IS-95

TDMAIS-136

PDC

2G 1990sDigital

Technologies

drive

3GIMT-2000

UMTS

WCDMA

cdma2000

Demands

drive

TD-

SCDMA

3G provides compositive services for both operators and subscribers


5/98


3G Evolution

Proposal of 3G

IMT-2000: the general name of third generation mobile

communication system

The third generation mobile communication was first

proposed in 1985and was renamed as IMT-2000 in theyear of 1996

Commercialization: around the year of 2000

Work band : around 2000MHz

The highest service rate :up to 2000Kbps


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3G Spectrum Allocation


7/98HUAWEI TECHNOLOGIES CO., LTD. All rights reserved

Bands WCDMA Used

Main bands1920 ~ 1980MHz / 2110 ~ 2170MHz

Supplementary bands: different country maybe different

1850 ~ 1910 MHz / 1930 MHz ~ 1990 MHz (USA)

1710 ~ 1785MHz / 1805 ~ 1880MHz (Japan)

890 ~ 915MHz / 935 ~ 960MHz (Australia)

. . .

Frequency channel numbercentral frequency5, for main band:

UL frequency channel number 96129888

DL frequency channel number : 1056210838



3G Application Service

Time Delay

ErrorRatio

background

conversational

streaming

interactive



The Core technology of 3G: CDMA

CDMA

WCDMA

CN: based on MAP and GPRS

RTT: WCDMA

TD-SCDMACN: based on MAP and GPRS

RTT: TD-SCDMA

cdma2000CN: based on ANSI 41 and MIP

RTT: cdma2000



Contents

3G Overview

CDMA Principle



Physical Layer Overview Physical Channels




Multiple Access and Duplex Technology

Multiple Access Technology

Frequency division multiple access (FDMA)

Time division multiple access (TDMA)

Code division multiple access (CDMA)



Multiple Access Technology

Power

FDMA

Power

TDMA

Power

CDMA


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Multiple Access and Duplex Technology

Duplex Technology

Frequency division duplex (FDD)

Time division duplex (TDD)


14/98


Duplex Technology

Time

Frequency

Power

TDD

USER 2

USER 1

DL

UL

DL

DL

UL

FDD

Time

Frequency

Power

UL DL

USER 2

USER 1


15/98


Contents

3G Overview

CDMA Principle



Physical Layer Overview

Physical Channels



16/98


WCDMA Network Architecture

RNS

RNC

RNS

RNC

Core Network

Node B Node B Node B Node B

Iu-CS Iu-PS

Iur

Iub IubIub Iub

CN

UTRAN

UEUu

CS PS

Iu-CSIu-PS

CSPS


17/98


WCDMA Network Version Evolution

3GPP Rel993GPP Rel4

3GPP Rel5

2000 2001 2002

GSM/GPRS CN

WCDMA RTT

IMS

HSDPA 3GPP Rel6

MBMS

HSUPA

2005

CS domain change toNGN

WCDMA RTT


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WCDMA Network Version Evolution

Features of R6

MBMS is introduced

HSUPA is introduced to achieve the service rate up to 5.76Mbps

Features of R7

HSPA+ is introduced, which adopts higher order modulation and MIMO

Max DL rate: 28Mbps, Max UL rate:11Mbps

Features of R8

WCDMA LTE (Long term evolution) is introduced

OFDMA is adopted instead of CDMA

Max DL rate: 50Mbps, Max UL rate: 100Mbps (with 20MHz bandwidth)


19/98


Uu Interface protocol structure

L3

con

trol

c

ontrol

c

ontrol

con

trol

C-plane signaling U-plane information

PHY

L2/MAC

L1

RLC

DCNtGC

L2/RLC

MAC

RLCRLC

RLC

Duplication avoidance

UuS boundary

L2/BMC

control

PDCPPDCP L2/PDCP

DCNtGC

RRC

RLCRLC

RLC

RLC

BMC


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General Protocol Mode for UTRAN Terrestrial

Interface

The structure is based on the principle that the layers and planes arelogically independent of each other.

Application

Protocol

Data

Stream(s)

ALCAP(s)

Transport

Network

Layer

Physical Layer

Signaling

Bearer(s)

Control Plane User Plane

Transport Network

User Plane

Transport Network

Control Plane

Radio

Network

Layer

Signaling

Bearer(s)

Data

Bearer(s)

Transport Network

User Plane


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Iu-CS Interface

ALCAP

Control Plane

Transport Network

Control Plane

User planeRadioNetwork

Layer

Transport Network

User PlaneTransport

Network

LayerA B

RANAP

AAL2 PATH

ATM

Physical Layer

SAAL NNI

SCCP

MTP3-B

Iu UP

SAAL NNI

MTP3-B

Transport Network

User Plane


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Iu-PS Interface

Control Plane User planeRadio

Network

Layer

Transport Network

User PlaneTransportNetwork

Layer

Transport Network

User Plane

C

RANAP

ATM

SAAL NNI

SCCP

MTP3-B

Iu UP

AAL Type 5

IP

UDP

GTP-U

Physical Layer


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Iub Interface

ALCAP

Control Plane

Transport Network

Control Plane

User planeRadio

Network

Layer

Transport Network

User Plane

Transport

Network

Layer

Transport Network

User Plane

NBAP

AAL2 PATH

ATM

Physical Layer

SAAL UNI

Iub FP

SAAL UNI

NCP CCP


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Iur Interface

ALCAP

Control Plane

Transport Network

Control Plane

User planeRadioNetwork

Layer

Transport

Network

LayerA B

RANAP

AAL2 PATH

ATM

Physical Layer

SAAL NNI

SCCP

MTP3-B

Iur Data

Stream

SAAL NNI

MTP3-B

Transport Network

User PlaneTransport Network

User Plane


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Contents

3G Overview CDMA Principle




Physical Channels



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Processing Procedure of WCDMA System

Source

Coding

Channel Coding& Interleaving

Spreading Modulation

Source

DecodingChannel Decoding

& DeinterleavingDespreading Demodulation

Transmission

Reception

chipmodulated

signalbit symbol

Service

Signal

Radio

Channel

Service

Signal

Receiver


27/98


WCDMA Source Coding

AMR (Adaptive Multi-Rate) SpeechA integrated speech codec with 8 source

rates

The AMR bit rates can be controlled by the

RAN depending on the system load and

quality of the speech connections

Video Phone Service

H.324is used for VP Service in CS domain

Includes: video codec, speech codec, data

protocols, multiplexing and etc.

CODEC Bit Rate (kbps)

AMR_12.20 12.2 (GSM EFR)

AMR_10.20 10.2

AMR_7.95 7.95

AMR_7.40 7.4 (TDMA EFR)

AMR_6.70 6.7 (PDC EFR)

AMR_5.90 5.9

AMR_5.15 5.15

AMR_4.75 4.75


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Transmitter

Source

Coding



Source



Transmission

Reception

chipmodulated

signalbit symbol

Service

Signal

Radio

Channel

Service

Signal

Receiver


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WCDMA Block Coding - CRC

Block coding is used to detect if there are any uncorrectederrors left after error correction.

The cyclic redundancy check (CRC) is a common method of

block coding.

Adding the CRC bits is done before the channel encoding and

they are checked after the channel decoding.


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WCDMA Channel Coding

Effect

Enhance the correlation among symbols so as to recover the signal when

interference occurs

Provides better error correction at receiver, but brings increment of the delay

Types No Coding

Convolutional Coding (1/2, 1/3)

Turbo Coding (1/3)

Code Block

of N Bits

No Coding

1/2 ConvolutionalCoding

1/3 Convolutional

Coding

1/3 Turbo Coding

Uncoded N bits

Coded 2N+16 bits

Coded 3N+24 bits

Coded 3N+12 bits


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WCDMA Interleaving

Effect Interleaving is used to reduce the probability of consecutive bits error

Longer interleaving periods have better data protection with more delay

1110

1..... ... .

.. ... ... ... .

.. .000

0100

0 0 1 0 0 0 0 . . . 1 0 1 1 1

1110

1..... ... .

.. ... ... ... .

.. .000

00100 0 0 1 0 1 0 0 1 0 1 1

Inter-columnpermutation

Output bits

Input bits

Interleaving periods:

20, 40, or 80 ms


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Source

Coding



Source



Transmission

Reception

chipmodulated

signalbit symbol

Service

Signal

Radio

Channel

Service

Signal

Receiver


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Correlation

Correlation measures similarity between any two arbitrary signals. Identical and Orthogonal signals:

Correlation = 0

Orthogonal signals

-1 1 -1 1

-1 1 -1 1

1 1 1 1

+1

-1

+1

-1

+1

-1

+1

-1

Correlation = 1Identical signals

-1 1 -1 1

1 1 1 1

-1 1 -1 1

C1

C2+1

+1

C1

C2


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Orthogonal Code Usage - Coding

UE1: 1 1

UE2: 1 1

C1 : 1 1 1 1 1 1 1 1

C2 : 1 1 1 1 1 1 1 1

UE1c1 1 1 1 1 1 1 1 1

UE2c2 1 1 1 1 1 1 1 1

UE1c1

UE2c2

2 0 2 0 2 0 2 0


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Orthogonal Code Usage - Decoding

UE1C1 UE2C2: 2 0 2 0 2 0 2 0

UE1 Dispreading by c1: 1 1 1 1 1 1 1 1

Dispreading resul t : 2 0 2 0 2 0 2 0

Integral judgm ent: 4 (means

1) 4 (means

1)

UE2 Dispreading by c2: 1 1 1 1 1 1 1 1

Dispreading result: 2 0 2 0 2 0 2 0

Integral judgment: 4 (means

1) 4 (means

1)


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Spectrum Analysis of Spreading & Dispreading

Spreading code

Spreading code

Signal

Combination

Narrowband signal

f

P(f)

Broadband signal

P(f)

f

Noise & Other Signal

P(f)

f

Noise+Broadband signal

P(f)

f

Recovered signal

P(f)

f


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Spectrum Analysis of Spreading & Dispreading

Max allowed interference

Eb/NoRequiremen

t

Power

Max interference caused

by UE and others

Processing Gain

Ebit

Interference from

other UE Echip

Eb / No = Ec / No PG


38/98


Process Gain

Process Gain

Process gain differs for each service.

If the service bit rate is greater, the process gain is smaller,

UE needs more power for this service, then the coverage of

this service will be smaller, vice versa.

)ratebit

ratechiplog(10GainocessPr


39/98


Spreading Technology

Spreading consists of 2 steps: Channelization operation, which transforms data symbols into

chips

Scrambling operation is applied to the spreading signal

scramblingchannelization

Data

symbol

Chips after

spreading


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WCDMA Channelization Code

OVSF Code (Orthogonal Variable Spreading Factor) is used aschannelization code

SF = 8SF = 1 SF = 2 SF = 4

Cch,1,0 = (1)

Cch,2,0 = (1,1)

Cch,2,1 = (1, -1)

Cch,4,0 = (1,1,1,1)

Cch,4,1 = (1,1,-1,-1)

Cch,4,2 = (1,-1,1,-1)

Cch,4,3 = (1,-1,-1,1)

Cch,8,0 = (1,1,1,1,1,1,1,1)

Cch,8,1 = (1,1,1,1,-1,-1,-1,-1)

Cch,8,2 = (1,1,-1,-1,1,1,-1,-1)

Cch,8,3 = (1,1,-1,-1,-1,-1,1,1)

Cch,8,4 = (1,-1,1,-1,1,-1,1,-1)

Cch,8,5 = (1,-1,1,-1,-1,1,-1,1)

Cch,8,6 = (1,-1,-1,1,1,-1,-1,1)

Cch,8,7 = (1,-1,-1,1,-1,1,1,-1)


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WCDMA Channelization Code

SF = chip rate / symbol rateHigh data rates low SF code

Low data rates high SF code

Radio bearer SF Radio bearer SF

Speech 12.2 UL 64 Speech 12.2 DL 128

Data 64 kbps UL 16 Data 64 kbps DL 32





42/98


Purpose of Channelization Code

Channelization code is used to distinguish different physicalchannels of one transmitter

For downlink, channelization code ( OVSF code ) is used to

separate different physical channels of one cell

For uplink, channelization code ( OVSF code ) is used to

separate different physical channels of one UE


43/98


Purpose of Scrambling Code

Scrambling code is used to distinguish different transmittersFor downlink, scrambling code is used to separate different

cells in one carrier

For uplink, scrambling code is used to separate different

UEs in one carrier


44/98


Scrambling Code

Scrambling code: GOLD sequence. There are 224long uplink scrambling codes which are used for

scrambling of the uplink signals. Uplink scrambling codes are assigned

by RNC.

For downlink, 512 primary scrambling codes are used.


45/98


Primary Scrambling Code Group

Primary

scrambling

codes for

downlink

physical

channels

Group 0

Primary

scrambling code 0

Primaryscrambling code

8*63

Primaryscrambling code

8*63 +7512 primary

scrambling

codes

Group 1

Group 63

Primaryscrambling code 1

Primaryscrambling code 8

64 primary

scrambling code

groups

Each group consists of 8

primary scrambling codes


46/98


Code Multiplexing

Downlink Transmission on a Cell Level

Scrambling code

Channelization code 1



User 1 signal

User 2 signal

User 3 signal

NodeB


47/98


Code Multiplexing

Uplink Transmission on a Cell Level

NodeB

Scrambling code 3

User 3 signal

Channelization code

Scrambling code 2

User 2 signal

Channelization code

Scrambling code 1

User 1 signal

Channelization code


48/98



Source

Coding



Source



Transmission

Reception

chip modulatedsignalbit symbol

Service

Signal

Radio

Channel

Service

Signal

Receiver


49/98


Modulation Overview

1 00 1

time

Basic steady radio

wave:

carrier = A.cos(2pFt+)

Amplitude Shift

Keying:

A.cos(2p

Ft+

)

Frequency Shift

Keying:

A.cos(2p

Ft+

)

Phase Shift Keying:

A.cos(2p

Ft+

)

Data to be transmitted:Digital Input


50/98


Modulation Overview

Digital Modulation - BPSK

1

t

1 10

1

t-1

NRZ coding

fo

BPSK

Modulated

BPSKsignal

Carrier

Informationsignal

=0 =p =0

1 102 3 4 9875 6

1 102 3 4 9875 6

Digital Input

High Frequency

Carrier

BPSK Waveform


51/98


Modulation Overview

Digital Modulation - QPSK

-1 -1

1 102 3 4 9875 6

1 102 3 4 9875 6

NRZ Input

I di-Bit Stream

Q di-Bit Stream

I

Component

Q

Component

QPSK Waveform

1

1

-1

1

-1

1

1

-1

-1

-1

1 1 -1 1 -1 1 1 -1


52/98


Modulation Overview

NRZcoding

90o

NRZcoding

QPSK

Q(t)

I(t)

fo

A

A Acos(ot)

Acos(ot + p/2)

1 1p

/4

1 -1 7p

/4

-1 1 3p

/4

-1 -1 5p

/4

)cos(2: f oAQPSK


53/98


Demodulation

QPSK Constellation Diagram

1 102 3 4 9875 6

QPSK Waveform

1,1

-1,-1

-1,1

1,-1

1 -11 -1 1 -1-11-1 1

-1,1

NRZ Output


54/98


WCDMA Modulation

Different modulation methods corresponding to differenttransmitting abilities in air interface

HSDPA: QPSK or 16QAMR99/R4: QPSK


55/98



Source

Coding

ChannelCoding


Source

Decoding

Channel

DecodingDespreading Demodulation

Transmission

Reception

chip modulatedsignalbit symbol

Service

Signal

Radio

Channel

Service

Signal

Transmitter

Receiver


56/98


Wireless Propagation

Received

Signal

TransmittedSignal

Transmission Loss:

Path Loss + Multi-path Fading

Time

Amplitude


57/98


Propagation of Radio Signal

Signal at Transmitter

Signal at Receiver

-40

-35

-30

-25

-20

-15

-10

-5

dB

0

0dBm

-20-15

-10

-5

5

10

15

20

Fading


58/98


Fading Categories

Fading Categories

Slow Fading

Fast Fading


59/98


Diversity Technique

Diversity technique is used to obtain uncorrelated signals forcombining

Reduce the effects of fading

Fast fading caused by multi-path

Slow fading caused by shadowing

Improve the reliability of communication

Increase the coverage and capacity


60/98


Diversity

Time diversityChannel coding, Block interleaving

Frequency diversity

The user signal is distributed on the whole bandwidth

frequency spectrum

Space diversity

Polarization diversity


61/98


Principle of RAKE Receiver

Receive set

Correlator 1

Correlator 2

Correlator 3

Searcher correlator Calculate the

time delay and

signal strength

CombinerThe

combined

signal

tt

s(t) s(t)

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

performance of the system


62/98


Contents

3G Overview

CDMA Principle




Physical Channels



63/98


UTRAN Network Structure

RNS

RNC

RNS

RNC

Core Network

NodeB NodeB NodeB NodeB

Iu-CS Iu-PS

Iur

Iub IubIub Iub

CN

UTRAN

UEUu

CS PS

Iu-CSIu-PS

CSPS


64/98


RAB, RB and RL

RAB

RB

RLNodeB

RNCCNUE

UTRAN


65/98


Contents

3G Overview

CDMA Principle




Physical Channels



66/98


WCDMA Radio Interface Channel Definition

Logical Channel = information container

Defined by is transferred

Transport Channel = characteristics of transmission

Described by and with data is

transmitted over the radio interface

Physical Channel = specification of the information global content

providing the real transmission resource, maybe a frequency , a

specific set of codes and phase


67/98


Logical Channel

Control channel

Traffic channel

Dedicated traffic channel (DTCH)

Common traffic channel (CTCH)

Broadcast control channel (BCCH)

Paging control channel (PCCH)

Dedicate control channel (DCCH)

Common control channel (CCCH)


68/98


Transport Channel

Dedicated Channel (DCH)

Broadcast channel (BCH)

Forward access channel

(FACH)

Paging channel (PCH)

Random access channel (RACH)

High-speed downlink shared channel

(HS-DSCH)

Common transport

channel

Dedicated transport

channel


69/98


Physical Channel

A physical channel is defined by a specific carrier frequency, code

(scrambling code, spreading code) and relative phase.

In UMTS system, the different code (scrambling code or spreading

code) can distinguish the channels.

Most channels consist of radio frames and time slots, and each radio

frame consists of 15 time slots.

Two types of physical channel: UL and DL

Physical Channel

Frequency, Code, Phase


70/98


Downlink Physical Channel

Downlink Dedicated Physical Channel (DL DPCH)

Downlink Common Physical Channel

Primary Common Control Physical Channel (P-CCPCH)

Secondary Common Control Physical Channel (S-CCPCH)

Synchronization Channel (SCH)

Paging Indicator Channel (PICH)

Acquisition Indicator Channel (AICH)

Common Pilot Channel (CPICH)

High-Speed Physical Downlink Shared Channel (HS-PDSCH)

High-Speed Shared Control Channel (HS-SCCH)


71/98


Uplink Physical Channel

Uplink Dedicated Physical Channel

Uplink Dedicated Physical Data Channel (Uplink DPDCH)

Uplink Dedicated Physical Control Channel (Uplink DPCCH)

High-Speed Dedicated Physical Channel (HS-DPCCH)

Uplink Common Physical Channel

Physical Random Access Channel (PRACH)

Function of Physical Channel


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Function of Physical Channel

NodeB UE

P-CCPCH-Primary Common Control Physical Channel

P-CPICH--Primary Common Pilot Channel

SCH--Synchronisation Channel

Cell Search Channels

DPDCH--Dedicated Physical Data Channel

DPCCH--Dedicated Physical Control Channel

Dedicated Channels

Paging Channels

PICH--Paging Indicator Channel

SCCPCH--Secondary Common Control Physical Channel

PRACH--Physical Random Access Channel

AICH--Acquisition Indicator Channel

Random Access Channels

HS-DPCCH--High Speed Dedicated Physical Control Channel

HS-SCCH--High Speed Share Control Channel

HS-PDSCH--High Speed Physical Downlink Share Channel

High Speed Downl ink Share Channels


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Synchronization Channels (P-SCH & S-SCH)

Used for cell search

Two sub channels: P-SCH and S-SCH

SCH is transmitted at the first 256 chips of

every time slot

Primary synchronization code is transmitted

repeatedly in each time slot

Secondary synchronization code specifies the

scrambling code groups of the cell

Primary

SCH

Secondary

SCH

Slot #0 Slot #1 Slot #14

acsi,0

pac pac pac

acsi,1 acs

i,14

256 chips

2560 chips

One 10 ms SCH radio frame


74/98


Secondary Synchronization Channel (S-SCH)

slot numberScramblingCode Group #0 #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14

Group 0 1 1 2 8 9 10 15 8 10 16 2 7 15 7 16

Group 1 1 1 5 16 7 3 14 16 3 10 5 12 14 12 10

Group 2 1 2 1 15 5 5 12 16 6 11 2 16 11 15 12

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

Group 4 1 2 16 6 6 11 15 5 12 1 15 12 16 11 2

Group 61 9 10 13 10 11 15 15 9 16 12 14 13 16 14 11

Group 62 9 11 12 15 12 9 13 13 11 14 10 16 15 14 16

Group 63 9 12 10 15 13 14 9 14 15 11 11 13 12 16 10

..acp

Slot # ?

P-SCH acp

Slot #?

16 6S-SCH

acp

Slot #?

11Group 2

Slot 7, 8, 9256 chips


75/98


Primary Common Pilot Channel (PCPICH)

Primary PCPICH

Carrying pre-defined sequence

Fixed channel code: Cch, 256, 0, Fixed rate 30Kbps

Scrambled by the primary scrambling code

Broadcast over the entire cellA phase reference for SCH, Primary CCPCH, AICH, PICH and

downlink DPCH, Only one PCPICH per cell

Pre-defined symbol sequence

Slot #0 Slot #1 Slot # i Slot #14

Tslot= 2560 chips , 20 bits

1 radio frame: Tr= 10 ms

Primary Common Control Physical Channel


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Primary Common Control Physical Channel

(PCCPCH)

Carrying BCH transport channel

Fixed rate, fixed OVSF code (30kbpsCch, 256, 1)

The PCCPCH is not transmitted during the first 256 chips of each time

slot

PCCPCH Data

18 bits

Slot #0

1 radio frame: Tf

= 10 ms

Slot #1 Slot #i

256 chips

Slot #14

Tslot

= 2560 chips,20 bits

SCH


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Paging Indicator Channel (PICH)

Carrying Paging Indicators (PI)

Fixed rate (30kbps), SF = 256

N paging indicators {PI0, , PIN-1} in each PICH frame, N=18, 36, 72,

or 144

One radio frame (10 ms)

b1b0

288 bits for paging indication 12 bits (undefined)

b287 b288 b299

Secondary Common Control Physical Channel


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Secondary Common Control Physical Channel

(SCCPCH)

Carrying FACH and PCH, SF = 256 - 4

Pilot: used for demodulation

TFCI: Transport Format Control Indication, used for describe data

format

Data

N bits

Slot #0 Slot #1 Slot #i Slot #14

1 radio frame: T f = 10 ms

T slot = 2560 chips,

Data

Pilot

N bitsPilotN bitsTFCI

TFCI

20*2 k bits (k=0..6)


79/98


Physical Random Access Channel (PRACH)

Carrying uplink signaling and data, consist of two parts:

One or several preambles: 16 kinds of available preambles

10 or 20ms message part

Message partPreamble

4096 chips10 ms (one radio frame)

Preamble Preamble

Message partPreamble

4096 chips 20 ms (two radio frames)

Preamble Preamble


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PRACH Message Structure

Pilot

N bits

Slot # 0 Slot # 1 Slot # i Slot # 14

Message part radio frame T = 10

ms

Tslot = 2560 chips, 10*2

Pilot

TFCI

N bitsTFCI

Data

Ndata

bitsData

Control

kbits (k=0..3)


81/98


PRACH Access Timeslot Structure

#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14

5120 chips

radio frame: 10 ms radio frame: 10 ms

Access slot #0

Random Access Transmission

Access slot #1

Access slot #7

Access slot #14



Random Access TransmissionAccess slot #8


82/98


Acquisition Indicator Channel (AICH)

Carrying the Acquisition Indicators (AI), SF = 256

There are 16 kinds of Signature to generate AI

AS #14 AS #0 AS #1 AS #i AS #14 AS #0

a1 a2a0 a31 a32a30 a33 a38 a39

AI part Unused part

20 ms



83/98



(DPDCH&DPCCH)

Uplink DPDCH and DPCCH are I/Q code division multiplexed

(CDM) within each radio frame

DPDCH carries data generated at Layer 2 and higher layer, the

OVSF code is Cch,SF,SF/4, where SF is from 256 to 4

DPCCH carries control information generated at Layer 1, the

OVSF code is Cch,256,0



84/98



(DPDCH&DPCCH)

Frame Structure of Uplink DPDCH/DPCCH

Pilot

Npilotbits

TPC

NTPCbits

DataNdatabits


Tslot= 2560 chips, 10*2k bits (k=0..6)

1 radio frame: Tf = 10 ms

DPDCH

DPCCH

FBI

NFBIbits

TFCI

NTFCIbits

Downlink Dedicated Physical Channel


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(DPDCH+DPCCH)

Downlink DPDCH and DPCCH is time division multiplexing

(TDM).

DPDCH carries data generated at Layer 2 and higher layer

DPCCH carries control information generated at Layer 1

SF of downlink DPCH is from 512 to 4



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(DPDCH+DPCCH)

Frame Structure of Downlink DPCH (DPDCH+DPCCH)

One radio frame, Tf= 10 ms


Tslot= 2560 chips, 20*2kbits (k=-1..6)

Data2

Ndata2bits

DPDCH

TFCI

NTFCIbits

Pilot

Npilotbits

Data1

Ndata1 bits

DPDCH DPCCH DPCCH

TPC

NTPCbits

High-Speed Physical Downlink Shared Channel


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High Speed Physical Downlink Shared Channel

(HS-PDSCH)

Bearing service data and layer 2 overhead bits mapped from the

transport channel

SF=16, can be configured several channels to increase data service

Slot #0 Slot#1 Slot #2

Tslot= 2560 chips, M*10*2kbits (k=4)

DataNdata1bits

1 subframe: Tf= 2 ms

High-Speed Shared Control Channel


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g p

(HS-SCCH)

Carries physical layer signalling to a single UE ,such as modulation scheme

(1 bit) ,channelization code set (7 bit), transport block size (6bit),HARQprocess number (3bit), redundancy version (3bit), new data indicator (1bit),

UE identity (16bit)

HS-SCCH is a fixed rate (60 kbps, SF=128) downlink physical channel

used to carry downlink signalling related to HS-DSCH transmission

Slot #0 Slot#1 Slot #2

Tslot= 2560 chips, 40 bits

DataNdata1bits

1 subframe: Tf= 2 ms

High-Speed Dedicated Physical Control Channel


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g p y

(HS-DPCCH )

Carrying information to acknowledge downlink transport blocks and

feedback information to the system for scheduling and link adaptation

of transport block

CQI and ACK/NACK

Physical Channel, Uplink, SF=256

Subframe #0 Subframe #i Subframe #n

One HS-DPCCH subframe ( 2ms )

ACK/NACK

1 radio frame: Tf= 10 ms

CQI

Tslot= 2560 chips 2

Tslot= 5120 chips

M i B t Ch l


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Mapping Between Channels

Logical channels Transport channels Physical channels

BCCH BCH P-CCPCH

FACH S-CCPCH

PCCH PCH S-CCPCH

CCCH RACH PRACH

FACH S-CCPCH

CTCH FACH S-CCPCH

DCCH, DTCH DCH DPDCH

HS-DSCH HS-PDSCH

RACH, FACH PRACH, S-CCPCH

C t t


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Contents

3G Overview

CDMA Principle




Physical Channels


Synchronization Procedure Cell Search


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Synchronization Procedure - Cell Search

Frame synchronization &

Code Group Identification

Scrambling Code

Identification

UE uses SSC to find framesynchronization and identify the code

group of the cell found in the first step

UE determines the primary scrambling

code through correlation over thePCPICH with all codes within the

identified group, and then detects the P-

CCPCH and reads BCH information

Slot

Synchronization

UE uses PSC to acquire slot

synchronization to a cell

Random Access ProcedureSTART


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Choose a RACH sub channel from

available ones

Get available signatures

Set Preamble Retrans Max

Set Preamble_Initial_Power

Send a preamble

Check the corresponding AI

Increase message part power by

p-m based on preamble power

Set physical status to be RACH

message transmittedSet physical status to be Nack

on AICH received

Choose a access slot again

Counter> 0 & Preamble power

< maximum allowed power

Choose a signature andincrease preamble transmit power

Set physical status to be Nack

on AICH received

Get negative AI

No AI

Report the physical status to MAC

END

Get positive AI

The counter of preamble retransmit

Subtract 1, Commanded preamble power

increased by Power Ramp Step

N

Y

Send the corresponding message part

Transmit Diversity Mode


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Transmit Diversity Mode

Application of Tx diversity modes on downlink physical channel

Physical channel type Open loop mode Closed loop mode

TSTD STTD Mode 1 Mode 2

P-CCPCH applied

SCH applied

S-CCPCH applied

DPCH applied applied applied

PICH applied

HS-PDSCH applied applied

HS-SCCH applied

AICH applied

Transmit Diversity STTD


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Transmit Diversity - STTD

Space time block coding based transmit antenna diversity

(STTD)

4 consecutive bits b0, b1, b2, b3 using STTD coding

b0 b1 b2 b3 Antenna 1

Antenna 2Channel bits

STTD encoded channel bits

for antenna 1 and antenna 2.

b0 b1 b2 b3

-b2 b3 b0 -b1

Transmit Diversity TSTD


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Transmit Diversity - TSTD

Time switching transmit diversity (TSTD) is used only on SCH

channel

Antenna 1

Antenna 2

i,0

i,1

acsi,14

Slot #0 Slot #1 Slot #14

i,2

acp

Slot #2

(Tx

OFF)(Tx

OFF)

(Tx

OFF)

(TxOFF)

(Tx

OFF)

(Tx

OFF)

(Tx

OFF)

acp acp

acsacs

acp

acs(Tx

OFF)

Closed Loop Mode


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Closed Loop Mode

Used in DPCH and HS-PDSCH


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Thank You

www.huawei.com

WCDMA Principle-20110930-B-V1.0.ppt

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Transcript of WCDMA Principle-20110930-B-V1.0.ppt