wcdma channel structure and function

8/11/2019 WCDMA Channel Structure and Function

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WR_BT03_E1_0Channel Structure and function

Purpose

Master WCDMA channel structure

Master physical layer procedure


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CONTENTS

1 Chanel structure............................................................................................................................................1

1.1 Channels of UTRAN...........................................................................................................................1

1.1.1 Loical channels.......................................................................................................................!

1.1.! Transport channels...................................................................................................................."

1.1." Physical channels......................................................................................................................#

1.1.$ Channel Mappin...................................................................................................................!1

1.! Physical layer porcedure....................................................................................................................!!

1.!.1 Cell search procedure.............................................................................................................!!

1.!.! Rando% Access Procedure.....................................................................................................!"


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1 Chanel structure

knowledgeent

%appin of loical channels onto transport channels

%appin of transport channels and physical channels

physical layer procedure

1!1 Channels of "TR#N

Channels of UTRAN are di&ided into

loical channels

transport channels

physical channels

'n air interface protocol %odele of UTRAN( MAC layer acco%plish the %appin ofloical channels onto transport channels( P)* layer acco%plish the %appin of

transport channels onto physical channels. +i 1.1 ,1sho-s the position of loical

channels and transport channels


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Duplication A&oidance

C Nt DC

C Nt DC

RLCRLC

RLCRLC

RLCRLC

RLCRLC

/MC

PDCPPDCP

C,plane sinallin U,plane infor%ationUu0 oundary

control

control

control

control

L"

Radio

/earers

L!2PDCP

L!2/MC

L!2RLC

Loical

Channels

L!2MAC

TransportChannels

L1

controlRRC

MAC

P)*

+i1.1,1 loical channels and transport channels

1!1!1 $ogical channels

MAC layer i%ple%ent the %appin et-een loical channel and transport channel and

pro&ide data transport ser&ice for loical. Loical channels are di&ided into control

channel and traffic channel. +i illustrates the structure of loical channels3

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Chapter 1 Chanel structure

+i1.1,! Loical channel structure

Control channels only used to transport control plane infor%ation. 'ncludin

/CC)(PCC)(CCC)(DCC)(0)CC).

Traffic channels only used to transport user plane infor%ation. 'nculudin

DTC)(CTC).

1!1!% Trans&ort channels

Transport channels are ser&ices offered y Layer 1 to the hiher layersA transport

channel is defined y ho- and -ith -hat characteristics data is transferred o&er the air

interface. A eneral classification of transport channels is into t-o roups3

, Dedicated channel3 used y dedicated user.

, Co%%on channel3 used y all users -ithin one cell.

0ho- as+i 1.1 ,"

3


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WR4/T5"46145 Channel 0tructure and function

/C)

PC)

+AC)

D0C)

RAC)

CPC)

DC)

DC)

+i1.1," transport channels

There e7ists only one type of dedicated transport channel( the Dedicated Channel

8DC)9. The Dedicated Channel 8DC)9 is a do-nlin: or uplin: transport channel. The

DC) is trans%itted o&er the entire cell or o&er only a part of the cell usin e.. ea%,

for%in antennas.

There are si7 types of co%%on transport channels3 /C)( +AC)( PC)( RAC)( CPC)

and D0C).

/roadcast Channel ,/C)

The /roadcast Channel 8/C)9 is a do-nlin: transport channel that is used to

roadcast syste%, and cell,specific infor%ation. The /C) is al-ays trans%itted

o&er the entire cell and has a sinle transport for%at.

+or-ard Access Channel ,+AC)

The +or-ard Access Channel 8+AC)9 is a do-nlin: transport channel. The +AC) is

trans%itted o&er the entire cell. 't is used to trans%it control i%for%ation after

/asestation ha&e recei&ed the rando% access re;uire%ent sent y U6. +AC) is also

can e used to send pa:et data.

There is one or se&eral +AC) -ithin one cell.


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trans%itted o&er the entire cell. The trans%ission of the PC) is associated -ith the

trans%ission of physical,layer enerated Pain 'ndicators( to support efficient sleep,

%ode procedures.

Rando% Access Channel , RAC)

The Rando% Access Channel 8RAC)9 is an uplin: transport channel. The RAC) is

al-ays recei&ed fro% the entire cell. 't is used to carry control infor%ation 8such as call

setup re;uest9 sent y U6.The RAC) is characteri=ed y a collision ris: and y ein

trans%itted usin open loop po-er control.

Co%%non Pac:et Channel , CPC)

The Co%%on Pac:et Channel 8CPC)9 is an uplin: transport channel. CPC) is

associated -ith a dedicated channel on the do-nlin: -hich pro&ides po-er control and

CPC) Control Co%%ands 8e.. 6%erency 0top9 for the uplin: CPC). The CPC) is

characterised y initial collision ris: and y ein trans%itted usin inner loop po-er

control.

Do-nlin: 0hared Channel , D0C)

The Do-nlin: 0hared Channel 8D0C)9 is a do-nlin: transport channel shared y

se&eral U6s The D0C) is associated -ith one or se&eral do-nlin: DC). The D0C) is

trans%itted o&er the entire cell or o&er only a part of the cell usin e.. ea%,for%in

antennas.

1!1!3 'h(sical channels

Physical channels are defined y a specific carrier fre;uency( scra%lin code(

channeli=ation code 8optional9( ti%e start > stop 8i&in a duration9 and( on the uplin:(

relati&e phase 85 or 2!9. There is ! types of physical channel. Uplin: physical and

do-nlin: physical.

1!1!3!1 "&link &h(sical channels

There are ! types of uplin: dedicated physical channels8Uplin: Dedicated Physical

Data Channel and Uplin: Dedicated Physical Control Channel9 and ! types of uplin:

co%%on physical channels8 Physical Rando% Access Channel and Physical Co%%on

Pac:et Channel9 illustrate as +i 1.1 ,$

5


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+i1.1,$ uplin: physical channels

Uplink dedicated physical channels

There are t-o types of uplin: dedicated physical channels( the uplin: Dedicated

Physical Data Channel 8uplin: DPDC)9 and the uplin: Dedicated Physical Control

Channel 8uplin: DPCC)9.The DPDC) and the DPCC) are '2? code %ultiple7ed

-ithin each radio fra%e

The uplin: DPDC) is used to carry the DC) transport channel. There %ay e =ero(

one( or se&eral uplin: DPDC)s on each radio lin:.

The uplin: DPCC) is used to carry control infor%ation enerated at Layer 1. The

Layer 1 control infor%ation consists of :no-n pilot its to support channel esti%ation

for coherent detection( trans%it po-er,control 8TPC9 co%%ands( feedac: infor%ation

8+/'9( and an optional transport,for%at co%ination indicator 8T+C'9. The transport,

for%at co%ination indicator infor%s the recei&er aout the instantaneous transport

for%at co%ination of the transport channels %apped to the si%ultaneously trans%itted

uplin: DPDC) radio fra%e. There is one and only one uplin: DPCC) on each radio

lin:.

+i 1.1 ,#sho-s the fra%e structure of the uplin: dedicated physical channels. 6ach

radio fra%e of lenth 15 %s is split into 1# slots( each of lenth T slot@ !#5 chips(

correspondin to one po-er,control period.

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+i1.1,# fra%e structure of uplin: dedicated physical channel

The para%eter : in fiure deter%ines the nu%er of its per uplin: DPDC) slot. 't is

related to the spreadin factor 0+ of the DPDC) as 0+ @ !#2! :. The DPDC)

spreadin factor %ay rane fro% !# do-n to $. The spreadin factor of the uplin:

DPCC) is al-ays e;ual to !#( i.e. there are 15 its per uplin: DPCC) slot.

The e7act nu%er of its of the uplin: DPDC) and the different uplin: DPCC) fields

8Npilot( NT+C'( N+/'( and NTPC9 is confiured y hiher layers and can also e reconfiured

y hiher layers.

The +/' its are used to support techni;ues re;uirin feedac: fro% the U6 to the

UTRAN Access Point( includin closed loop %ode trans%it di&ersity and site selection

di&ersity trans%ission 800DT9.

There are t-o types of uplin: dedicated physical channelsB those that include T+C'

8e.. for se&eral si%ultaneous ser&ices9 and those that do not include T+C' 8e.. for

fi7ed,rate ser&ices9. 't is the UTRAN that deter%ines if a T+C' should e trans%itted

and it is %andatory for all U6s to support the use of T+C' in the uplin:.

Npilot"$#and The shado-ed colu%n part of pilot it pattern is

defined as +0W and +0Ws can e used to confir% fra%e synchroni=ation. 8The &alue

of the pilot it pattern other than +0Ws shall e E1E.9

TPC is correspondin to po-er contrl co%%and.

Multi,code operation is possile for the uplin: dedicated physical channels. When

%ulti,code trans%ission is used( se&eral parallel DPDC) are trans%itted usin

different channeli=ation codes. )o-e&er( there is only one DPCC) per radio lin:.

!


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Uplink common physical channels

'h(sical Rando #ccess Channel )'R#C*+

The rando%,access trans%ission is ased on a 0lotted AL


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control parts are trans%itted in parallel.

A 15 %s %essae part consists of one %essae part radio fra%e( -hile a !5 %s %essaepart consists of t-o consecuti&e 15 %s %essae part radio fra%es. The %essae part

lenth is e;ual to the Trans%ission Ti%e 'nter&al of the RAC) Transport channel in

use. This TT' lenth is confiured y hiher layers.

The data part consists of 15H!:its( -here :@5(1(!(". This corresponds to a spreadin

factor of !#( 1!( $( and "! respecti&ely for the %essae data part.

The control part consists of :no-n pilot its to support channel esti%ation for

coherent detection and ! T+C' its. This corresponds to a spreadin factor of !# for

the %essae control part. The pilot it pattern is descried in tale . The total nu%er

of T+C' its in the rando%,access %essae is 1#H! @ "5. The T+C' of a radio fra%e

indicates the transport for%at of the RAC) transport channel %apped to the

si%ultaneously trans%itted %essae part radio fra%e. 'n case of a !5 %s PRAC)

%essae part( the T+C' is repeated in the second radio fra%e.

'h(sical Coon 'acket Channel'C'C*

The Physical Co%%on Pac:et Channel 8PCPC)9 is used to carry the CPC) CPC).

The CPC) trans%ission is ased on D0MA,CD approach -ith fast ac;uisition

indication. The U6 can start trans%ission at the einnin of a nu%er of -ell,defined

ti%e,inter&als( relati&e to the fra%e oundary of the recei&ed /C) of the current cell.

The PCPC) access trans%ission consists of one or se&eral Access Prea%les IA,PJ of

lenth $5F chips( one Collision Detection Prea%le 8CD,P9 of lenth $5F chips( a

DPCC) Po-er Control Prea%le 8PC,P9 -hich is either 5 slots or slots in lenth(

and a %essae of &ariale lenth N715 %s.

#


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Pilot

Npilotits

TPC

NTPCits

Data

Ndataits

0lot G5 0lot G1 0lot Gi 0lot G1$

Tslot@ !#5 chips( 15H!:its 8:@5..9

1 radio fra%e3 Tf@ 15 %s

Data

Control+/'

N+/'itsT+C'

NT+C'its

+i 1.1, fra%e structure of CPC)

CPC) access prea%le part

0i%ilar to RAC) prea%le part. The RAC) prea%le sinature se;uences are

used. The nu%er of se;uences used could e less than the ones used in the

RAC) prea%le. The scra%lin code could either e chosen to e a different

code se%ent of the old code used to for% the scra%lin code of the RAC)

prea%les or could e the sa%e scra%lin code in case the sinature set is

shared.

CPC) collision detection prea%le part

0i%ilar to RAC) prea%le part. The RAC) prea%le sinature se;uences are

used. The scra%lin code is chosen to e a different code se%ent of the old

code used to for% the scra%lin code for the RAC) and CPC) prea%les

CPC) po-er control prea%le part

$


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The po-er control prea%le se%ent is called the CPC) Po-er Control

Prea%le 8PC,P9 part. The Po-er Control Prea%le lenth is a hiher layer

para%eter( Lpc,prea%le( -hich shall ta:e the &alue 5 or slots. The T+C' field is

filled -ith E1E its.

CPC) %essae part

0i%ilar to uplin: dedicated channel( 6ach 15 %s fra%e is split into 1# slots( each

of lenth Tslot @ !#5 chips. 6ach slot consists of t-o parts( a data part that

carries hiher layer infor%ation and a control part that carries Layer 1 control

infor%ation. The data and control parts are trans%itted in parallel. The sf of

CPC) %essae part is !#

1!1!3!% ,ownlink &h(sical channel

Do-nlin: physical channels include Detedicated physical channel K one 0hared

Physical ChannelK fi&e Co%%non Control Channel

do-nlin: Detedicated physical channel ,DPC)

pri%ary and secondary Co%%non Pilot Channel , CP'C)

pri%ary and secondary Co%%on Control Physicl Channel , CCPC)

0ynchronous Channel , 0C)

Physical Do-nlin: 0hared Channel , D0C)

Ac;uisition 'ndication Channel , A'C)

Pain 'ndication Channel , P'C)

do-nlin: physical are illustrated as+i 1.1 ,


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+i1.1, %&

Downlink Dedicated Physical Channel

There is only one type of do-nlin: dedicated physical channel( the Do-nlin:

Dedicated Physical Channel 8do-nlin: DPC)9.

Within one do-nlin: DPC)( dedicated data enerated at Layer ! and ao&e( i.e. the

dedicated transport channel 8DC)9( is trans%itted in ti%e,%ultiple7 -ith control

infor%ation enerated at Layer 1 8:no-n pilot its( TPC co%%ands( and an optional

T+C'9. The do-nlin: DPC) can thus e seen as a ti%e %ultiple7 of a do-nlin:

DPDC) and a do-nlin: DPCC).

6ach fra%e of lenth 15 %s is split into 1# slots( each of lenth Tslot @ !#5 chips(

correspondin to one po-er,control period.

+i 1.1,F fra%e structure of DL DPC)

2


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The para%eter : in fiure F deter%ines the total nu%er of its per do-nlin: DPC)

slot. 't is related to the spreadin factor 0+ of the physical channel as 0+ @ #1!2! :. The

spreadin factor %ay thus rane fro% #1! do-n to $.

The e7act nu%er of its of the different do-nlin: DPC) fields 8Npilot( NTPC( NT+C'(

Ndata1and Ndata!9 is i&en in tale 11. What slot for%at to use is confiured y hiher

layers and can also e reconfiured y hiher layers.

There are asically t-o types of do-nlin: Dedicated Physical ChannelsB those that

include T+C' 8e.. for se&eral si%ultaneous ser&ices9 and those that do not include

T+C' 8e.. for fi7ed,rate ser&ices9. 't is the UTRAN that deter%ines if a T+C' should

e trans%itted and it is %andatory for all U6s to support the use of T+C' in thedo-nlin:.

Npilot!$ > 1

TPC sy%ol is correspondin to transi%ission po-er control co%%and T

'5(or'1(

Downlink Common Physical Channel

Coon 'ilot Channel )C'-C*+

The CP'C) is a fi7ed rate 8"5 :ps( 0+@!#9 do-nlin: physical channel that carries a

pre,defined it se;uence. There are t-o types of Co%%on pilot channels( the Pri%ary

and 0econdary CP'C). They differ in their use and the li%itations placed on their

physical features.+i sho- the fra%e structure of CP'C).

Pre,defined it se;uence


Tslot @ !#A5 chips ( !5 its

1 radio fra%e3 T @ 15 %s

3


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slot G1

+ra%eGi1+ra%eGi

slot G1$

Antenna !

Antenna 1

slot G5

+ra%e /oundary

5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5

1 1 1 1 5 5 5 5 1 1 1 1 5 5 5 5 1 1 5 5 1 1 1 1 5 5 5 5 1 1 1 1 5 5 5 5 1 1 1 1 5 5 5 5 1 1 1 1

The Pri%ary Co%%on Pilot Channel 8P,CP'C)9 has the follo-in characteristics3

, The sa%e channeli=ation code is al-ays used for the P,CP'C)( see I$JB

, The P,CP'C) is scra%led y the pri%ary scra%lin code( see I$JB

, There is one and only one P,CP'C) per cellB

, The P,CP'C) is roadcast o&er the entire cell.

The Pri%ary CP'C) is a phase reference for the follo-in do-nlin: channels3 0C)(

Pri%ary CCPC)( A'C)( P'C) AP,A'C)( CD2CA,'C)( C0'C)( DL,DPCC) for

CPC) and the 0,CCPC). /y default( the Pri%ary CP'C) is also a phase reference for

do-nlin: DPC) and any associated PD0C). The U6 is infor%ed y hiher layer

sinallin if the P,CP'C) is not a phase reference for a do-nlin: DPC) and any

associated PD0C).The Pri%ary CP'C) is al-ays a phase reference for a do-nlin:

physical channel usin closed loop T di&ersity.

A 0econdary Co%%on Pilot Channel 80,CP'C)9 has the follo-in characteristics3

, An aritrary channeli=ation code of 0+@!# is used for the 0,CP'C)( see I$JB

, A 0,CP'C) is scra%led y either the pri%ary or a secondary scra%lin code(

, There %ay e =ero( one( or se&eral 0,CP'C) per cellB

, A 0,CP'C) %ay e trans%itted o&er the entire cell or only o&er a part of the cellB

A 0econdary CP'C) %ay e a phase reference for a do-nlin: DPC). 'f this is the

case( the U6 is infor%ed aout this y hiher,layer sinallin.The 0econdary CP'C)

can e a phase reference for a do-nlin: physical channel usin open loop T di&ersity(

instead of the Pri%ary CP'C) ein a phase reference.

Note that it is possile that neither the P,CP'C) nor any 0,CP'C) is a phase reference

for a do-nlin: DPC).

'riar( Conon Control 'h(sical Channel )'.CC'C*+

Co%%on control physical channel consists of Pri%ary Co%%on Control Physical

4


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Channel 8PCCPC)9 and 0econdary Co%%on Control Physical Channel 80CCPC)9.

The Pri%ary CCPC) is a fi7ed rate 8"5 :ps( 0+@!#9 do-nlin: physical channelsused to carry the /C) transport channel.

Data

Ndata1@1 its


Tslot@ !#5 chips ( !5 its


8T7


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can e %apped to the sa%e or to separate 0econdary CCPC)s.

'f +AC) and PC) are %apped to the sa%e 0econdary CCPC)( they can e %apped tothe sa%e fra%e. The %ain difference et-een a CCPC) and a do-nlin: dedicated

physical channel is that a CCPC) is not inner,loop po-er controlled. The %ain

difference et-een the Pri%ary and 0econdary CCPC) is that the transport channel

%apped to the Pri%ary CCPC) 8/C)9 can only ha&e a fi7ed predefined transport

for%at co%ination( -hile the 0econdary CCPC) support %ultiple transport for%at

co%inations usin T+C'.

S(nchronous Channel )SC*+

The 0ynchronisation Channel 80C)9 is a do-nlin: sinal used for cell search. The

0C) consists of t-o su channels( the Pri%ary and 0econdary 0C). The 15 %s radio

fra%es of the Pri%ary and 0econdary 0C) are di&ided into 1# slots( each of lenth

!#5 chips. +iure illustrates the structure of the 0C) radio fra%e.

PrimarySCH

SecondarySCH

256 chips

2560 chips

One 10 ms SCH radio frame

acs ,

acp

acs ,

acp

acs ,

acp

Slot #0 Slot #1 Slot #14

The Pri%ary 0C) consists of a %odulated code of lenth !# chips( the Pri%ary

0ynchronisation Code 8P0C9 denoted cpin fiure ( trans%itted once e&ery slot. The

P0C is the sa%e for e&ery cell in the syste%.

The 0econdary 0C) consists of repeatedly trans%ittin a lenth 1# se;uence of%odulated codes of lenth !# chips( the 0econdary 0ynchronisation Codes 800C9(

trans%itted in parallel -ith the Pri%ary 0C). The 00C is denoted csi(:in fiure ( -here

i @ 5( 1( ( " is the nu%er of the scra%lin code roup( and k@ 5( 1( ( 1$ is the

slot nu%er. 6ach 00C is chosen fro% a set of 1 different codes of lenth !#. This

se;uence on the 0econdary 0C) indicates -hich of the code roups the cellOs do-nlin:

scra%lin code elons to.

'h(sical ,ownlink Shared Channel )',SC*+

The Physical Do-nlin: 0hared Channel 8PD0C)9 is used to carry the Do-nlin:

6


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0hared Channel 8D0C)9.

A PD0C) corresponds to a channelisation code elo- or at a PD0C) rootchannelisation code. A PD0C) is allocated on a radio fra%e asis to a sinle U6.

Within one radio fra%e( UTRAN %ay allocate different PD0C)s under the sa%e

PD0C) root channelisation code to different U6s ased on code %ultiple7in. Within

the sa%e radio fra%e( %ultiple parallel PD0C)s( -ith the sa%e spreadin factor( %ay

e allocated to a sinle U6. This is a special case of %ulticode trans%ission. All the

PD0C)s are operated -ith radio fra%e synchronisation.

PD0C)s allocated to the sa%e U6 on different radio fra%es %ay ha&e different

spreadin factors.

The fra%e and slot structure of the PD0C) are sho-n on fiure .


Tslot@ !#5 chips( !5H!:its 8:@5..9

Data

Ndata1its


+or each radio fra%e( each PD0C) is associated -ith one do-nlin: DPC). The

PD0C) and associated DPC) do not necessarily ha&e the sa%e spreadin factors and

are not necessarily fra%e alined.

All rele&ant Layer 1 control infor%ation is trans%itted on the DPCC) part of the

associated DPC)( i.e. the PD0C) does not carry Layer 1 infor%ation. To indicate for

U6 that there is data to decode on the D0C)( the T+C' field of the associated DPC)

shall e used.

The T+C' infor%s the U6 of the instantaneous transport for%at para%eters related to

the PD0C) as -ell as the channelisation code of the PD0C).

#c/usition -ndication Channel)#-C*+

The Ac;uisition 'ndicator channel 8A'C)9 is a fi7ed rate 80+@!#9 physical channel

used to carry Ac;uisition 'ndicators 8A'9. Ac;uisition 'ndicator A's corresponds to

sinature s on the PRAC).

!


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+iure illustrates the structure of the A'C). The A'C) consists of a repeated se;uence

of 1# consecuti&e access slots 8A09( each of lenth #1!5 chips. 6ach access slot

consists of t-o parts( anAcquisition-Indicator 8A'9 part consistin of "! real,&alued

sy%ols a5( ( a"1and a part of duration 15!$ chips -ith no trans%ission that is not

for%ally part of the A'C). The part of the slot -ith no trans%ission is reser&ed for

possile use y C0'C) or possile future use y other physical channels.

The spreadin factor 80+9 used for channelisation of the A'C) is !#.

The phase reference for the A'C) is the Pri%ary CP'C).

1024 chips

Transmission Off

#S 1 #S 0 #S 1 #S i #S 1 #S 0

a1 a%a0 a31a30

! part "406 chips, $2 real%&al'ed sym(ols

20 ms

C'C* #ccess 'rea2le #c/usition -ndication Channel )#'.#-C*+

The Access Prea%le Ac;uisition 'ndicator channel 8AP,A'C)9 is a fi7ed rate80+@!#9 physical channel used to carry AP ac;uisition indicators 8AP'9 of CPC). AP

ac;uisition indicator AP'scorresponds to AP sinaturestrans%itted y U6.

AP,A'C) and A'C) %ay use the sa%e or different channelisation codes.The phase

reference for the AP,A'C) is the Pri%ary CP'C). +iure illustrates the structure of

AP,A'C).

1024 chips

Transmission Off

#S 1 #S 0 #S 1 #S i #S 1 #S 0

a1 a%a0 a31a30

P! part " 406 chips, $2 real%&al'ed sym(ols

20 ms

The AP,A'C) has a part of duration $5F chips -here the AP ac;uisition indicator

8AP'9 is trans%itted( follo-ed y a part of duration 15!$chips -ith no trans%ission

that is not for%ally part of the AP,A'C). The part of the slot -ith no trans%ission is

"


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reser&ed for possile use y C0'C) or possile future use y other physical channels.

CPCH Collision Detection/Channel Assignment Indicator Channel

)C,C# .-C*+

The Collision Detection Channel Assin%ent 'ndicator channel 8CD2CA,'C)9 is a

fi7ed rate 80+@!#9 physical channel used to carry CD 'ndicator 8CD'9 only if the CA

is not acti&e( or CD 'ndicator2CA 'ndicator 8CD'2CA'9 at the sa%e ti%e if the CA is

acti&e. The structure of CD2CA,'C) is sho-n in fiure .

1024 chips

Transmission Off

#S 1 #S 0 #S 1 #S i #S 1 #S 0

a1 a%a0 a31a30

C)!*C! part " 406 chips, $2 real%&al'ed sym(ols

20 ms

CD2CA,'C) and AP,A'C) %ay use the sa%e or different channelisation codes.

The CD2CA,'C) has a part of duration of $5Fchips -here the CD'2CA' is

trans%itted( follo-ed y a part of duration 15!$chips -ith no trans%ission that is not

for%ally part of the CD2CA,'C). The part of the slot -ith no trans%ission is reser&ed

for possile use y C0'C) or possile future use y other physical channels.

The spreadin factor 80+9 used for channelisation of the CD2CA,'C) is !#.

'aging -ndication Channel )'-C*+

The Pain 'ndicator Channel 8P'C)9 is a fi7ed rate 80+@!#9 physical channel used to

carry the pain indicators. The P'C) is al-ays associated -ith an 0,CCPC) to -hich

a PC) transport channel is %apped.

+iure !$ illustrates the fra%e structure of the P'C).


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(1(0

2++ (its for pain indication12 (its -transmission

off.

One radio frame -10 ms.

(2+/ (2++ (2

'n each P'C) fra%e( Np pain indicators P5( ( PNp,1Q are trans%itted( -here

Np@1( "( !( or 1$$.

The P' calculated y hiher layers for use for a certain U6( is associated to the pain

indicator Pq( -here q is co%puted as a function of the P' co%puted y hiher layers(the 0+N of the P,CCPC) radio fra%e durin -hich the start of the P'C) radio fra%e

occurs( and the nu%er of pain indicators per fra%e 8Np93

( )( )( ) NpNp

SFNSFNSFNSFNPIq %od1$$

1$$%od#1!2$221

++++=

+urther( the P' calculated y hiher layers is associated -ith the &alue of the pain

indicator Pq. 'f a pain indicator in a certain fra%e is set to E1E it is an indication that

U6s associated -ith this pain indicator and P' should read the correspondin fra%e

of the associated 0,CCPC).

The P' it%ap in the PC) data fra%es o&er 'u contains indication &alues for all hiher

layer P' &alues possile. 6ach it in the it%ap indicates if the pain indicator

associated -ith that particular P' shall e set to 5 or 1. )ence( the calculation in the

for%ula ao&e is to e perfor%ed in Node / to %a:e the association et-een P' and

Pq..The %appin fro% P5( ( PNp,1Q to the P'C) its 5( ( !Q are accordin to

Tale 1.1 ,1.

Tale 1.1,1 Mappin of pain indicators P;to P'C) its

Nu%er of pain indicators per

fra%e 8Np9

P;@ 1 P;@ 5

Np@1 1;( ( 1;1#Q @ 1( 1(( 1Q 1;( ( 1;1#Q @ 5( 5(( 5Q

Np@" ;( ( ;Q @ 1( 1(( 1Q ;( ( ;Q @ 5( 5(( 5Q

Np@! $;( ( $;"Q @ 1( 1(( 1Q $;( ( $;"Q @ 5( 5(( 5Q

Np@1$$ !;( !;1Q @ 1( 1Q !;( !;1Q @ 5( 5Q

2$


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1!1! Channel 4a&&ing

1!1!!1 4a&&ing 2etween logical channels and trans&ort channels

+i1.1,15 illustrates the %appin et-een loical channel and transport channels.

+i1.1,15 %appin et-een loical channel and transport channels

+i1.1,11 illustrates the %appin et-een transport channel and physical channels.

+i1.1,11 %appin et-een transport channel and physical channels.

'n addition to the transport channels introduced earlier( there e7ist physical channels

tocarry only infor%ation rele&ant to physical layer procedures. The 0ynchronisation

Channel80C)9( the Co%%on Pilot Channel 8CP'C)9 and the Ac;uisition 'ndication

2


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Channel 8A'C)9are not directly &isile to hiher layers and are %andatory fro% the

syste% function point of&ie-( to e trans%itted fro% e&ery ase station. The CPC)

0tatus 'ndication Channel8C0'C)9 and the Collision Detection2Channel Assin%ent

'ndication Channel 8CD2CA,'C)9 are needed if CPC) is used.

1!% 'h(sical la(er &orcedure

1!%!1 Cell search &rocedure

Durin the cell search( the U6 searches for a cell and deter%ines the do-nlin:

scra%lin code and fra%e synchronisation of that cell. The cell search is typically

carried out in three steps3

0tep 13 slot synchronous

Durin the first step of the cell search procedure the U6 uses the 0C)s pri%ary

synchronisation code to ac;uire slot synchronisation to a cell. This is typically done

-ith a sinle %atched filter 8or any si%ilar de&ice9 %atched to the pri%ary

synchronisation code -hich is co%%on to all cells. The slot ti%in of the cell can e

otained y detectin pea:s in the %atched filter output.

0tep !3 fra%e synchronous and code,roup identification

Durin the second step of the cell search procedure( the U6 uses the 0C)s secondary

synchronisation code to find fra%e synchronisation and identify the code roup of the

cell found in the first step. This is done y correlatin the recei&ed sinal -ith all

possile secondary synchronisation code se;uences( and identifyin the %a7i%u%

correlation &alue. 0ince the cyclic shifts of the se;uences are uni;ue the code roup as

-ell as the fra%e synchronisation is deter%ined.

0tep "3 scra%lin,code identification

Durin the third and last step of the cell search procedure( the U6 deter%ines the e7act

pri%ary scra%lin code used y the found cell. The pri%ary scra%lin code is

typically identified throuh sy%ol,y,sy%ol correlation o&er the CP'C) -ith all

codes -ithin the code roup identified in the second step. After the pri%ary scra%lin

code has een identified( the Pri%ary CCPC) can e detected.And the syste%, and cell

specific /C) infor%ation can e read.

22


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1!%!% Rando #ccess 'rocedure

At each initiation of the physical rando% access procedure( Layer 1 shall recei&e the

follo-in infor%ation fro% the hiher layers 8MAC93

, The Transport +or%at to e used for the PRAC) %essae part.

, The A0C of the PRAC) trans%ission.

, The data to e trans%itted 8Transport /loc: 0et9.

The physical rando%,access procedure shall e perfor%ed as follo-s3

1. Deri&e the a&ailale uplin: access slots( in the ne7t full access slot set( for the

set of a&ailale RAC) su,channels -ithin the A0C Rando%ly select one

access slot a%on the ones pre&iously deter%ined. 'f there is no access slot

a&ailale in the selected set( rando%ly select one uplin: access slot

correspondin to the set of a&ailale RAC) su,channels -ithin the i&en A0C

fro% the ne7t access slot set. The rando% function shall e such that each of the

allo-ed selections is chosen -ith e;ual proaility.

!. Rando%ly select a sinature fro% the set of a&ailale sinatures -ithin the i&en

A0C. The rando% function shall e such that each of the allo-ed selections is

chosen -ith e;ual proaility.

". 0et the Prea%le Retrans%ission Counter to Prea%le Retrans Ma7.

$. 0et the para%eter Co%%anded Prea%le Po-er to Prea%le4'nitial4Po-er.

#. 'n the case that the Co%%anded Prea%le Po-er e7ceeds the %a7i%u% allo-ed

&alue( set the prea%le trans%ission po-er to the %a7i%u% allo-ed po-er. 'n

the case that the Co%%anded Prea%le Po-er is elo- the %ini%u% le&el

re;uired in IJ( set the prea%le trans%ission po-er to a &alue( -hich shall e at

or ao&e the Co%%anded Prea%le Po-er and at or elo- the re;uired%ini%u% po-er specified in IJ.


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!9 Rando%ly select a ne- sinature fro% the set of a&ailale sinatures -ithin the

i&en A0C. The rando% function shall e such that each of the allo-ed

selections is chosen -ith e;ual proaility.

"9 'ncrease the Co%%anded Prea%le Po-er y P5 @ Po-er Ra%p 0tep Id/J. 'f

the Co%%anded Prea%le Po-er e7ceeds the %a7i%u% allo-ed po-er y d/(

the U6 %ay pass L1 status 8ENo ac: on A'C)E9 to the hiher layers 8MAC9 and

e7it the physical rando% access procedure.

$9 Decrease the Prea%le Retrans%ission Counter y one.

#9 'f the Prea%le Retrans%ission Counter 5 then repeat fro% step #.

wcdma channel structure and function

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