W(Level1) UMTS Radio Interface Physical Layer 20040728 a 1[1].0

7/27/2019 W(Level1) UMTS Radio Interface Physical Layer 20040728 a 1[1].0

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Wireless Curriculum Development Section

ISSUEUMTS Radio Interface Physical Layer

1.0


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Confidential Information of Huawei.

No Spreading without Permission. Security Level: Internal

Course Contents

Chapter 1 Physical Layer Overview

Chapter 2 Physical Channels and Channel Mapping

Chapter 3 Physical Layer Processing Procedure

Chapter 4 Physical Layer Procedure


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UTRAN Protocol Structure

RNS

RNC

RNS

RNC

Core Network

Node B Node B Node B Node B

Iu Iu

Iur

Iub IubIub Iub


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Air Interface Protocol Structure

Radio Resource Control (RRC)

Medium Access Control

Transport channels

Physical layerControl/Measurements

Layer 3

Logical channelsLayer 2

Layer 1


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Data Processing at Physical Layer

Data from MAC

LayerTB

Channel coding

and multiplexing

Spreading and

modulation


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Physical Channel

A physical channel is defined by a specific carrier frequency,

code (scrambling code, spreading code) and relative phase.

In CDMA 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


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Spreading Technology

Spreading consists of 2 steps Channelization operationwhich transforms data symbols into

chips. Thus increasing the bandwidth of the signal,.The number of

chips per data symbol is called the Spreading FactorSF.Theoperation is done by multiplying with OVSF code.

Scrambling operation is applied to the spreading signal .

Data

bit

OVSF

code

Scrambling

code

Chips

after

spreading


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Channelization Code

OVSF code is used as channelizaiton code

The channelization codes are uniquely described as

Cch,SF,k, where SF is the spreading factor of the code

and kis the code number, 0 k SF-1.

SF = 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)


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Scrambling codeGOLD sequence. Scrambling code period : 10ms ,or 38400 chips.

The code used for scrambling of the uplink DPCCH/DPDCH may

be of either long or short type, There are 224 long and 224 short

uplink scrambling codes. Uplink scrambling codes are assigned

by higher layers.

For downlink physical channels, a total of 218-1 = 262,143

scrambling codes can be generated. scrambling codes k = 0, 1,, 8191 are used.

Scrambling Code


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Scrambling

codes for

downlink

physical

channels

Set 0

Set 1

Set 511

Primaryscrambling code 0

Secondaryscrambling code 1

Secondaryscrambling code

15

Primaryscrambling code

51116

Secondaryscrambling code

51116158192

scrambling

codes

512 sets

A primary scrambling code and 15 secondary scrambling codes are included in a set.

Primary Scrambling Code


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Group 0

Groupe1

Group 63

512 primary

scrambling codes

64 primary scrambling

code groupsEach group consists of 8

primary scrambling codes

Primary Scrambling Code Group

Primary

scramblingcodes for

downlink

physical

channels





8*63


63*87


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Course Contents






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2.1 Physical Channel Structure

and Funct ion

2.2 Channel Mapping


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Downlink Physical Channel

Downlink Common Physical Channel

Common Control Physical Channel (CCPCH)

Synchronization Packet Channel (SCH)

Physical Downlink Shared Channel (PDSCH)

Paging Indicator Channel (PICH)

Acquisition Indicator Channel (AICH)Common Pilot Channel (CPICH)

Downlink Dedicated Physical Channel

(Downlink DPCH)

Downlink

Physical

Channel


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Uplink Physical Channel

Uplink Common Physical Channel

Physical Random Access Channel (PRACH)

Physical Common Packet Channel (PCPCH)

Uplink Dedicated Physical Channel

Uplink Dedicated Physical Data

Channel (Uplink DPDCH)

Uplink Dedicated Physical Control

Channel (Uplink DPCCH)Uplink

Physical

Channel


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Synchronization Channel (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.

PSC is transmitted repeatedly

in each time slot.

SSC specifies the scrambling

code groups of the cell.

SSC is chosen from a set of

16 different codes of length

256, there are altogether 64

primary scrambling code

groups.

PrimarySCH

SecondarySCH

256 chips

2560 chips

One 10 ms SCH radio frame

acs,

acp

acs,

acp

acs,

acp

Slot #0 Slot #1 Slot #14


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Common Pilot Channel(CPICH)

Common Pilot CHannel (CPICH)

Carries pre-defined sequence.

Fixed rate 30KBPS SF=256 The CPICH uses the same channel and scrambling code but

different sequences in the case transmit diversity is used on

downlink channel

slot #1

Frame#i+1Frame#i

slot #14

A A A A A A A A A A A A A A A A A A A A A A A A

-A -A A A -A -A A A -A A -A -A A A -A -A A A -A -A A A -A -AAntenna 2

Antenna 1

slot #0

Frame Boundary


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Primary CPICH

Uses the same channel code--Cch, 256,0 Scrambled by the primary scrambling code

Only one CPICH per cell

Broadcast over the entire cell

The P-CPICH is a phase reference for SCH, Primary CCPCH,

AICH, PICH. By default, it is also a phase reference for

downlink DPCH.

Secondary CPICH

An arbitrary channel code of SF=256 is used for S-CPICH

S-CPICH is scrambled by either the primary or a secondary

scrambling code

There may be zero, one , or several secondary CPICH.

S-CPICH may be transmitted over part of the cell

S-CPICH may be a phase reference for S-CCPCH and downlink

DPCH.

Common Pilot Channel (CPICH)


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Fixed rate30kbpsSF=256 Carry BCH transport channel

The PCCPCH is not transmitted during the first 256 chips

of each time slot.

Only data part

STTD transmit diversity may be used

Data18 bits

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

Tslot = 2560 chips , 20 bits

1 radio frame: Tf = 10 ms

(Tx OFF)

256 chips

Primary Common Control Physical Channel

(P-CCPCH)


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Paging Indicator Channel (PICH)

One radio frame (10 ms)

b1b0

288 bits for paging indication 12 bits (undefined)

b287 b288 b299


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Paging Indicator Channel

PICH is a fixed-rate(SF=256) physical channel used to carry

the Paging Indicators (PI).

PICH is always associated with an S-CCPCH to which a PCH

transport channel is mapped.

Frame structure of PICHone frame of length 10ms consistsof 300 bits of which 288 bits are used to carry paging

indicators and the remaining 12 bits are not defined.

N paging indicators {PI0, , PIN-1} in each PICH frame,

N=18, 36, 72, or 144.

If a paging indicator in a certain frame is set to 1, it indicates

that UEs associated with this paging indicator should read

the corresponding frame of the associated S-CCPCH.


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Physical Random Access Channel (PRACH)

The random-access transmission data consists

of two parts:

One or several preambleseach preamble is of length4096chips and consists of 256 repetitions of a signature

whose length is 16 chips16 available signatures totally 10 or 20ms message part

Which signature is available and the length of message partare determined by higher layer


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PRACH Access Timeslot Structure

#0 #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 Transmission

Random Access Transmission

Random Access TransmissionAccess slot #8


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PRACH Transmission Structure

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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Pilot

Npilot bits

Data

Ndata bits


Tslot = 2560 chips, 10*2k

bits (k=0..3)

Message part radio frame TRACH = 10 ms

Data

ControlTFCI

NTFCI bits

PRACH Message Structure


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Acquisition Indicator Channel (AICH)

Frame structure of AICHtwo frames, 20 ms consists of arepeated sequence of 15 consecutive AS, each of length 20symbols(5120 chips). Each time slot consists of two partsanAcquisition-Indicator(AI) and a part of duration 1024chips with no

transmission.

Acquisition-Indicator AI have 16 kinds of Signature.

CPICH is the phase reference of AICH.

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


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Uplink Dedicated Physical Channel

DPDCH and DPCCH are I/Q code multiplexed within each

radio frame

DPDCH carries data generated at Layer 2 and higher layer

DPCCH carries control information generated at Layer 1

Each frame is 10ms and consists of 15 time slots, each

time slot consists of 2560 chips

The spreading factor of DPDCH is from 4 to 256

The spreading factor of DPDCH and DPCCH can be

different in the same Layer 1 connection

Each DPCCH time slot consists of Pilot, TFCIFBITPC


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Frame Structure of Uplink DPDCH/DPCCH

PilotNpilot bits

TPC

NTPC bits

DataNdata bits


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

1 radio frame: Tf = 10 ms

DPDCH

DPCCHFBI

NFBI bitsTFCI

NTFCI bits


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Functions of Uplink DPDCH/DPCCH

DCHData

DPDCH

DPCCH

Provide control data

for DPDCH, such as

demodulation, powercontrol, etc

Data bearerat physical layer


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Downlink Dedicated Physical Channel

DCH consists of dedicated data and control information.

Control information includesPilotTPCTFCI(optional). The spreading factor of DCH can be from 512 to 4,and can be

changed during connection

DPDCH and DPCCH is time multiplexed. Multi-code transmission within one CCTrCH uses the same

spreading factor. In this case, the DPCH control information

is transmitted only on the first downlink DPCH.

Different CCTrCH can use different spreading factors in the

case there are several CCTrCHs for one UE. In this case

information of only one DPCCH needs to be transmitted.


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Frame Structure of Downlink DPCH

One radio frame, Tf = 10 ms


Tslot = 2560 chips, 10*2

k

bits (k=0..7)

Data2

Ndata2 bits

DPDCH

TFCI

NTFCI bits

Pilot

Npilot bitsData1

Ndata1 bits

DPDCH DPCCH DPCCH

TPC

NTPC bits


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Functions of Downlink DPDCH/DPCCH

DCH

dataDPDCH

DPCCH

Provide control data

for DPDCH ,such as

demodulation, power

control,etc.

Data bearerat physical layer

DCH

data


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2.1 Physical Channel Structure

and Function

2.2 Channel Mapp ing


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Classification of Transport Channel

Broadcast Channel (BCH)

Forward Access Channel (FACH)

Paging Channel (PCH)

ReverseRandomAccess Channel (RACH)

Common Packet Channel (CPCH)Downlink Shared Channel (DSCH)

Dedicated Channel (DCH)

DCH may be UL or DL

Common

transport channel

Dedicated

transport channel


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{XOR}

TransportChannels

(L1 CharacteristicsDependent)

PCH BCH FACH RACH DCH

S-CCPCHP-CCPCHPhysical

ChannelsPRACH DPDCH

LogicalChannels

(DataDependent)

PCCH

DCCH

DTCH

DecicatedLogicalChannel

CipherOn

BCCH CCCH CTCH

HigherLayer data

Paging SystemInfo

Signalling CellBroadcastService

Signallingand

User data

DTCHDTCH

Channel Mapping


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Course Contents






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3.1 Coding and m ult ip lexing techno logy

3.2 Spreading technology

3.3 Modulation technology


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Transport channel multiplexing structure for downlink

102040 or 80ms

data

data

data

TrCH-i

dataCRC dataCRC dataCRC

dataCRCdataCRC dataCRCd a t aCBL CBL CBL

0816 or 24bits

Size Z

512Ktail Conventional code

5120KtailTurbo code

CedBL CedBL CedBLCoded data Conventional code orTurbo code

Rate matched data

Rate matched data DTXor

or

Data before 1st interleavingData after 1st interleaved

TrCH-1 TrCH-2 TrCH-ICCTrCHTrCH-1 TrCH-2 TrCH-I DTXCCTrCH

Ph-1 Ph-2 Ph-P

10ms

10msPh-1 Ph-2 Ph-P

TPC TFCI pilot

Spreading

Scrambling

TrCH-i+1

data1 data2 TPC TFCI pilotdata1 data2 TPC TFCI pilotdata1 data2

Radioframe

The number frames1

24 or 8Radioframe

Radioframe

Spreading

Scrambling

Spreading

Scrambling


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Error detection is provided on transport blocks through a

Cyclic Redundancy Check (CRC)

CRC size is informed by higher layer signal

08121624(optional) If no TB are input, no CRC bits should be attached. If TB

are input with TB SIZE=0,CRC bits shall be added, i.e. all

parity bits equal to zero.

CRC of TB


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TB Concatenation and Code Block Segmentation

All transport blocks in a TTI are serially concatenated .

The maximum size of the code blocks depends onwhether convolutional coding or turbo coding is used for

the TrCH .

Convolutional code: if TBS SIZE>504,segmented to multiple

code block of the same size.

Turbo code:if TBS SIZE>5114, segmented to multiple codeblock of the same size.

No coding:no segmentation

If codes cannot be segmented evenly, fill in 0 bits at the

beginning of the first code block.

If the code block length of Turbo code


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Channel coding

The following channel coding schemes can be applied to

TrCHs:

Convolutional coding, coding rates 1/3 and 1/2 are defined

Turbo coding, The coding rate of Turbo coder is 1/3

No coding

Usage of coding

BCHPCH and RACH1/2 Convolutional coding CPCH DCH DSCH and FACH1/2or1/3 Convolutional

coding ,1/3Turbo coding, no coding


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Rate Matching

Rate matching means that bits on a transport channel arerepeated or punctured.

The number of bits on a transport channel can vary

between different transmission time intervals. In the

downlink the transmission is interrupted if the number of

bits is lower than maximum. When the number of bits

between different transmission time intervals in uplink is

changed, bits are repeated or punctured to ensure that the

total bit rate after TrCH multiplexing is identical to the total

channel bit rate of the allocated dedicated physical

channels.


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Interleaving

Functionreduce the influence of fast fading. Two kinds of interleaving 1st interleaving and 2nd

interleaving

The length of 1st interleaving is TTI of TrCH, 1st interleaving

is a inter-frame interleaving

The length of 2nd interleaving is a physical frame , 2nd

interleaving is a intra-frame interleaving.


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Radio Frame Segmentation

When the transmission time interval is longer than 10 ms,

the input bit sequence is segmented and mapped onto

consecutive Fi radio frames.

Following radio frame size equalisation in the UL the input

bit sequence length is guaranteed to be an integer multipleof Fi.

Following rate matching in the DL the input bit sequence

length is guaranteed to be an integer multiple of Fi.


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Confidential Information of Huawei.No Spreading without Permission. Security Level: Internal

Multiplexing of TrCH

Every 10 ms, one radio frame from each TrCH is delivered to

the TrCH multiplexing. These radio frames are serially

multiplexed into a coded composite transport channel

(CCTrCH)

The format of CCTrCH is indicated by TFCI

TrCH can have different TTI before multiplexing

2 types of CCTrCH:Common and dedicated

Common CCTrCH should be multiplexed by common TrCH;

Dedicated CCTrCH should be multiplexed by dedicated TrCH

There is only one CCTrCH in uplink and one or several

CCTrCH in downlink for one user

Insertion of discontinuous transmission (DTX)


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Insertion of discontinuous transmission (DTX)

indication bits

In the downlink, DTX is used to fill up the radio frame with

bits.

DTX indication bits only indicate when the transmission

should be turned off, they are not transmitted.

1st insertion of DTX indication bits This step of inserting DTX indication bits is used only if the

positions of the TrCHs in the radio frame are fixed

2nd insertion of DTX indication bits

The DTX indication bits inserted in this step shall be placed at

the end of the radio frame.


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Physical Channel Segmentation and Mapping

When multiple physical channels are used, one CCTrCH radio

frame can be divided into multiple physical frames multicodetransmission

Each physical channel of multicode transmission must have

the same SF

DPCCH and DPDCH of uplink physical channel is code

multiplexed.

DPCCH and DPDCH of downlink physical channel is time

multiplexed

Uplink physical channel must be fully filled except when

cpmpressed mode is used

In downlink, the PhCHs do not need to be completely filled with

bits that are transmitted over the air. Values correspond to DTX

indicators, which are mapped to the DPCCH/DPDCH fields but

are not transmitted over the air.


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Physical Channel Forming Before Spreading

Each TrCH can carry different service data, several TrCHs

can be multiplexed into a CCTrCH, so WCDMA support

several service share a physical connection.

CCTrCH mapping to data part of physical channel.

TFCI,TPC and pilot bits generated at physical layer mappingto control part of physical channel ,and then spreading and

scrambling, transmitting at air interface at last.


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Example of Coding and Multiplexing

The number of TrChs 3

Transport block size 81, 103, and 60 bits

CRC 12 bits (attached only to TrCh#1)

Coding CC, coding rate = 1/3 for TrCh#1, 2 coding rate =1/2 for TrCh#3

TTI 20 ms

Transport block size 148 bits

Transport block set size 148 bits

CRC 16 bits

Coding CC, coding rate = 1/3

TTI 40 ms

Parameters for

12.2kb/s AMR speech

Parameters for

3.4kb/s control channel


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TrCh#1Transport block

CRC attachment

CRC

Tail bit attachment

Convolutionalcoding R=1/3, 1/2

Rate matching

81

81

303

Tail

893

303+NRM11st interleaving

12

Radio framese mentation

#1a

To TrCh Multiplexing

303 +NRM1

RF1 = (303 +NRM1)/2

RF2 = (333+ NRM2)/2

RF3 = (136+ NRM3)/2

#1b

TrCh#2

103

103

333

Tail

8103

333 +NRM2

#2a

TrCh#3

60

60

136

Tail

860

136 +NRM3

#3a136 +NRM3

#3b333 +NRM2

#2bRF1 RF1 RF2 RF2 RF3 RF3


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Example of Coding and Multiplexing(3.4kbps)

Transport block

CRC attachment

CRC

Convolutional

coding R=1/3

Rate matching

148

148

516*B

Tail

8*B

(516+NRM)*B

1st interleaving

16 bits

Radio framesegmentation

#1

[ (129+NRM)*B+NDI]/

4

To TrCh Multiplexing

(516+NRM)*B+NDI

#2 #4

Tail bit attachment

164*B

#3

TrBk concatination B TrBks (B =0,1)

164*B

(516+NRM)*B+NDI

Insertion of DTXindication*

[ (129+NRM)*B+NDI]/

4

[ (129+NRM)*B+NDI]/

4

[ (129+NRM)*B+NDI]/

4

* Insertion of DTX indication is used only if the position of the TrCHs in the radio frame is fixed.


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12.2 kbps data 3.4 kbps data

TrCH

multiplexing

30 ksps DPCH

2nd

interleaving

Physical channel

mapping

#1#1a #1c

1 2 15

CFN=4Nslot

Pilot symbol TPC

1 2 15

CFN=4N+1slot

1 2 15

CFN=4N+2slot

1 2 15

CFN=4N+3slot

#1b #2#2a #2c#2b #3#1a #1c#1b #4#2a #2c#2b

#1a #2a #1b #2b #1c #2c #1a #2a #1b #2b #1c #2c #1 #2 #3 #4

510 510 510 510

12.2 kbps data


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3.1 Coding and multiplexing technology

3.2 Spreading techno logy

3.3 Modulation technology


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Uplink DPCCH/DPDCH Spreading

I

cd,1 d

Slong,n or Sshort,n

I+jQ

DPDCH1

Q

cd,3 d

DPDCH3

cd,5 d

DPDCH5

cd,2 d

DPDCH2

cd,4 d

DPDCH4

cd,6 d

DPDCH6

cc c

DPCCH

The DPCCH is always spread by code cc = Cch,256,0

When only 1 DPDCH exists,(Cd,1 = Cch,SF,k)k=SF/4

The code used for scrambling of the uplink DPCCH/DPDCH may

be of either long or short type


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PRACH Spreading

Message part is shown in the following figurethevalue of gain factors is the same with DPDCH/DPCCH

ccc

cd d

Sr-msg,n

I+jQ

PRACH message

control part

PRACH message

data partI


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Downlink Spreading

I

Data ofphysicalchannelexceptSCH

S

P

Cch,SF,m

Sdl,n

Q

I+jQ S

Downlink physical channel except SCH is first serial-to-parallel

converted , spread by the spreading code, and then scrambledby a complex-valued scrambling code.

The beginning chip of the scrambling code is aligned with the

frame boundary of P-CCPCH.

Each channel have different gain factor

D li k S di


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Downlink Spreading

Different physical

annel come from point S

G1

G2

GP

GS

S-SCH

P-SCH

Ch t 3 Ph i l L P i P d


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3.1 Coding and multiplexing technology

3.2 Spreading technology

3.3 Modulat ion techno logy

U li k M d l ti


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Uplink Modulation

S

Im{S}

Re{S}

cos(t)

Complex-

valued

sequence

after

spreading

-sin(t)

Split

real &

imag

parts

Pulse

shaping

Pulse

shaping

The chip rate is 3.84Mbps

In the uplink, the complex-valued chip sequence generated

by the spreading process is QPSK modulated


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Downlink Modulation

The chip rate is 3.84Mbps

In the downlink, the complex-valued chip sequence

generated by the spreading process is QPSK modulated

S

Im{S}

Re{S}

cos(t)

Complex-

valued

sequence

after

spreading

-sin(t)

Split

real &

imag

parts

Pulse

shaping

Pulseshaping

C C t t


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Course Contents






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Synchronization ProcedureCell Search

Slot synchronization

Frame synchronization andcode-group identification

Scrambling-code

identification

UE uses PSC to acquire slot

synchronization to a cell

UE uses SSC to find frame

synchronization and identifythe code group of the cell

found in the first step

UE determines the primary scrambling

code through correlation over the

CPICH with all codes within the

identified group, and then detects the

P-CCPCH and reads BCH information

Synchronization Procedure Channel Timing


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Relationship

AICH accessslots

SecondarySCH

PrimarySCH

S-CCPCH,k

10 ms

PICH

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

P-CCPCH, (SFN modulo 2) = 0 P-CCPCH, (SFN modulo 2) = 1

Any CPICH

k:th S-CCPCH

PICH for k:th S-CCPCH

n:th DPCHDPCH,n

Any PDSCH

Synchronization ProcedureCommon Channel


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Synchronization

Common Channel Synchronization

The following physical channels have the same frame timing SCH(Primary and secondary)

CPICH(Primary and secondary)

P-CCPCH

PDSCH

P-CCPCHs radio frame timing is acquired by cell searchThe P-CCPCH on which the cell SFN is transmitted is used as timing

reference for all the physical channels

Synchronization ProcedureDedicated

Ch l S h i ti


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Channel Synchronization

Synchronization time relations of DPCH Different downlink DPCHs timing could be different, the offset

between the frame timing of DPCH and P-CCPCH should be

integer multiple of 256 chips, i.e, tDPCH,n=Tn*256 chipsTn={0,1,...149}

On UE side the transmitting time of uplink DPCCH/DPDCH is

T0(1024chips) after the 1st downlink detected path All UL DPCCH/DPDCHs from one UE have the same framing

timing.


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Random Access ProcedureRACH

Physical random access procedure

1 Derive the available uplink access slots, in the next full accessslot set, for the set of available RACH sub-channels within the given

ASC. Randomly select one access slot among the ones previously

determined. If there is no access slot available in the selected set,

randomly select one uplink access slot corresponding to the set of

available RACH sub-channels within the given ASC from the next

access slot set. The random function shall be such that each of the

allowed selections is chosen with equal probability 2Randomly select a signature from the set of available signatures

within the given ASC. 3 Set the Preamble Retransmission Counter to Preamble_

Retrans_ Max


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4 Set the parameter Commanded Preamble Power toPreamble_Initial_Power

5 Transmit a preamble using the selected uplink access slot,signature, and preamble transmission power.

6If no positive or negative acquisition indicator (AI +1 nor 1)corresponding to the selected signature is detected in the downlink

access slot corresponding to the selected uplink access slot:

aSelect the next available access slot in the set of availableRACH sub-channels within the given ASC

bselect a signature cIncrease the Commanded Preamble Power dDecrease the Preamble Retransmission Counter by one. If the

Preamble Retransmission Counter > 0 then repeat from step 6.

Otherwise exit the physical random access procedure.


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7 If a negative acquisition indicator corresponding to theselected signature is detected in the downlink access slot

corresponding to the selected uplink access slot, exit the

physical random access procedure Signature

8 If a positive acquisition indicator corresponding to theselected signature is detected , Transmit the random access

message three or four uplink access slots after the uplink

access slot of the last transmitted preamble

9exit the physical random access procedure


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Transmit diversity Mode

Application of Tx diversity modes on downlink physical channel

Physical channel type Open loopmode

Open loopmode

Closedloop

TSTD STTD Mode

P-CCPCH - applied -

SCH applied - -

S-CCPCH - applied -

DPCH - applied applied

PICH - applied -

PDSCH - applied applied

AICH - applied -

CSICH - applied -

T it Di it 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

b0 b1 b2 b3

-b2 b3 b0 -b1

Antenna 1

Antenna 2

Channel bits

STTD encoded channel bitsfor antenna 1 and antenna 2.

T it Di it TSTD


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Transmit Diversity-TSTD

Time switching transmit diversity (TSTD) is used only on

SCH channel.

Antenna 1

Antenna 2

acs,

acp

acs,

acp

acs,

acp

Slot #0 Slot #1 Slot #14

acs,

acp

Slot #2

(Tx OFF)(Tx OFF)

(Tx OFF)(Tx OFF)

(Tx OFF)(Tx OFF)

(Tx OFF)(Tx OFF)

T it Di it Cl d L M d


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Transmit DiversityClosed Loop Mode Closed loop mode transmit diversity

Used in DPCH and PDSCH Channel coding, interleaving and spreading are done as in non-

diversity mode. The spread complex valued signal is fed to

both TX antenna branches, and weighted with antenna specific

weight factors w1

and w2.

The weight factors are determined by the UE, and signalled tothe UTRAN access point (=cell transceiver) using the D-bits of

the FBI field of uplink DPCCH.

The calculation of weight factor is the key point of closed loop

Tx diversity.there are two modes with different calculation

methods of weight factor 1mode 1 uses phase adjustmentthe dedicated pilot symbols of

two antennas are different(orthogonal)

2mode 2 uses phase/amplitude adjustment the dedicated pilotsymbols of two antennas are the same.


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W(Level1) UMTS Radio Interface Physical Layer 20040728 a 1[1].0

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