network planning technology

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Wireless Network Planning Table of contents

Table of Contents

Chapter 11 Development of Network Planning Technology ....................................................11-111.1 GPRS Basic Principle ....................................................................................................11-1

11.1.1 GPRS Network Structure ....................................................................................11-1

11.1.2 GPRS BSS and S !unction "ntroduction ..........................................................11-2

11.1.# GPRS Signaling odel .......................................................................................11-$

11.1.$ Wireless Packet %&annel %onfiguration ..............................................................11-$

11.1.' Packet (ccess ode ...........................................................................................11-)

11.1.) Paging Processing ..............................................................................................11-*

11.1.* +iscontinuous Reception ,+R ..........................................................................11-/

11.1./ Wireless Resource +istribution ...........................................................................11-/

11.1.0 Packet S ste essage .....................................................................................11-0

11.1.13 Radio 4ink %ontrol .............................................................................................11-0

11.1.11 %&annel %odec and %S %&ange %ontrol .........................................................11-13

11.1.12 Radio 4ink onitoring .....................................................................................11-13

11.1.1# Radio !re5uenc Power %ontrol .....................................................................11-11

11.1.1$ %ell Reselection %ontrol ..................................................................................11-11

11.1.1' !low %ontrol and 6oS Guarantee ...................................................................11-12

11.1.1) obilit anage ent and %o unications anage ent ..............................11-1#11.2 GPRS Network Planning .............................................................................................11-1$

11.2.1 GPRS %apacit Planning ..................................................................................11-1$

11.2.2 GPRS %o7erage Planning ................................................................................11-1)

11.2.# GPRS !re5uenc Planning ...............................................................................11-10

11.2.$ Su ar ...........................................................................................................11-2311.# W%+ ( S ste 87er7iew ..........................................................................................11-21

11.#.1 9 TS S ste Network %o position ................................................................11-22

11.#.2 S ste "nterface ...............................................................................................11-2$

11.#.# Basic Principle of Spread Spectru %o unication ........................................11-2$

11.#.$ So e of t&e :e Tec&nologies in t&e W%+ ( S ste .....................................11-2/11.#.' T&e Recei7e Sensiti7it of t&e W%+ ( S ste ...............................................11-#2

11.$ W%+ ( S ste Network Planning .............................................................................11-#$

11.$.1 T&e %ontent of t&e W%+ ( Network Planning .................................................11-#$

11.$.2 W%+ ( Wireless %apacit %alculation ............................................................11-#*

11.$.# W%+ ( Ser7ice +escription and %alculation ...................................................11-$'

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Wireless Network Planning %&apter 11 +e7elop ent of Network Planning Tec&olog

Chapter 1 Development of Network Planning

Technology1.1 GPR !asic Principle

1.1.1 GPR Network tr"ct"re

GPRS network &as introduced suc& concepts as packet switc&ing and packettrans ission; w&ic& en&anced GS network


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Gf

D

Gi

Gn

GbGc

CE

Gp

Gs

Signalling and DataTransfer Interface

Signalling Interface

MSC/VLR

TE MT BSS TEPDN

R U

Gr !

"LR

#t$er PLMN

SGSN

GGSN

Gd

SM%SCSMS%GMSCSMS%I&MSC

GGSN

EIR

SGSN

Gn

Figure 11-2 GPRS Network Composition

1.1.# GPR ! an$ % &"nction 'ntro$"ction

'. ! C

BS% is t&e core control part of t&e GS >GPRS base station subs ste . 8ne BS%can control se7eral BTSs.

!or circuit-switc&ed ser7ices; t&e ain responsibilities of BS% include?

@arious kinds of wireless resources anage ent

T&e apping fro t&e wireless ser7ice c&annel to terrestrial circuitA%ircuit-switc&ed call controlA

( interface support and (bis interface support.

!or packet-switc&ed ser7ices; t&e responsibilities of BS% include?

Packet wireless c&annel configurationA

%ontrolling t&e con7ersion of t&e wireless c&annel between packet-switc&ed ser7ices and circuit-switc&ed ser7icesA

Pro7iding necessar packet calling control support for cells wit&outPB%% .

Besides; t&e operation and aintenance co ands on BTS 7ia 8 % ust becontrolled or transferred b BS%; and t&e c&annel configuration for t&e P%9 and t&ePb>G-(bis interface configuration are ainl conducted at BS%.

''. !T

BTS is t&e wireless part of t&e BSS; and controlled b BS%; BTS is t&e wirelesstranscei7ing e5uip ent ser7ing a specific or se7eral cells.

T&e ain responsibilities of BTS include?

RealiCing t&e wireless trans ission and t&e related control functionbetween BTS and S 7ia t&e 9 interfaceA

(cco plis&ing t&e la er 1 and la er 2 functions of t&e 9 interface;and transparentl trans itting la er # essageA

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elping BS% acco plis& part of t&e la er # function of t&e 9interface.

'''. PC(

P%9 is t&e e5uip ent introduced b BSS to support GPRS; and its ain functionsinclude?

ost of t&e packet wireless resource anage ent functionsA

Packet calling control functionA

Packet data trans issionA

Supporting t&e Gb interface; t&e G-(bis interface; and t&e Pb interface

'). GPR %

,1 Ter inal D5uip ent

Ter inal D5uip ent ,TD is t&e co puter ter inal e5uip ent operated andaintained b ter inal subscribers. "t is used to transcei7e t&e packet data of

ter inal subscribers in t&e GPRS s ste .TD can be independent desktop co puter.T&e functions of TD can also be integrated into t&e &and-&eld obile ter inale5uip ent; and beco e one entit wit& t&e obile ter inal , T . To so e e=tent; allt&e functions pro7ided b t&e GPRS network are to set up a packet data transportpassagewa between TD and e=ternal data networks.

,2 obile Ter inal

obile Ter inal , T on t&e one &and co unicates wit& TDA on t&e ot&er itco unicates wit& BTS 7ia air interface; and t&e logic link to SGSN can beestablis&ed. T&e T of GPRS ust be configured wit& GPRS function software toaccess GPRS s ste ser7ices. "n t&e data co unications process; fro t&eperspecti7e of TD; t&e function of T is e5ui7alent to t&e ode connecting TD to t&eGPRS s ste . T&e functions of T and TD can be integrated into one p& sical

de7ice.,# obile Station

obile Station , S can be 7iewed as t&e integrated entit wit& all t&e functions of Tand TD. "t can be one p& sical entit or two ,TDE T .

S &as t&ree t pes?

T pe (? it allows si ultaneous packet switc&ing ser7ice and circuit switc&ing ser7ice.

T pe B? it can be attac&ed to t&e GPRS network and t&e GS networksi ultaneousl ; but it does not allow t&e si ultaneous circuit switc&ing ser7ice andpacket switc&ing ser7ice.

T pe %? it cannot attac& to t&e GPRS network and t&e GS network si ultaneousl .

,$ S ultiple ti e slot %apabilit 4e7el

S can be di7ided into 20 le7els based on t&e ultiple ti e slot capabilit ; w&ic& &asbeen detailed in t&e following table. Ss at different le7els &a7e different packetc&annels si ultaneousl a7ailable. ( &andset reports its ultiple ti e slot capabilitle7el in t&e packet resource re5uest infor ation. BSS s&ould co pre&ensi7elconsider suc& aspects as t&e S data traffic; re5uired class of 5ualit of ser7ices;a7ailable wireless c&annel condition; etc. w&en assigning wireless resources for S.T&e ultiple ti e slot capabilit of S s&ould tr to be et wit& t&e obser7ance of t&eprinciple of aking full use of t&e wireless resources. T&e ultiple ti e slot capabilitis usuall represented as ,R E ,T ; t&at is t&e a=i u ti e slot nu ber allowed for t&e downlink and t&e a=i u ti e slot nu ber allowed for t&e uplink.!or e=a ple; #E1 GPRS &andset refers to t&e one wit& t&ree ti e slots a=i allallowed for t&e downlink reception and one ti e slot a=i all allowed for t&e uplink

trans ission.

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Multislot

classMaximum number of slots Multislot

classMaximum number of slots

Rx Tx Sum Rx Tx Sum1 1 1 2 16 6 6 NA2 2 1 1! ! ! NA

2 2 1" " " NA# 1 # 1$ 6 2 NA% 2 2 # 2& 6 NA6 2 # 21 6 # NA! # 22 6 # NA" # 1 % 2 6 6 NA$ 2 % 2# " 2 NA

1& # 2 % 2% " NA11 # % 26 " # NA12 # # % 2! " # NA1 NA 2" " 6 NA1# # # NA 2$ " " NA1% % % NA

1.1.* GPR ignaling %o$el

T&e signaling odel of GPRS BSS is s&own as in !igure 11-#. "ts ain responsibilitis to acco plis& t&e protocol la er function suc& as R4%> (%; BSSGP; and NS; as

well as t&e air interface radio fre5uenc related functions.

BSSGPRela'

GMM/SM

LLC

RLC

M!C

GSM R(

GMM/SM

LLC

BSSGP

L)bis

U GbMS BSS SGSN

Net*+r, Ser-ice

RLC

M!C

GSM R( L)bis

Net*+r, Ser-ice

G ? GPRS obilit anage ent 44%? 4ogical 4ink %ontrol

R4%? Radio 4ink %ontrol (%? ediu (ccess %ontrolBSSGP? Base Station S ste GPRS Protocol

S ? Session anage ent

Figure 11-3 T'e Si(nalin( Mo)el of GPRS *SS

1.1.+ ,ireless Packet Channel Config"ration

'. ,ireless Packet ogic Channel Types

T&e wireless packet logic c&annels include t&e following four t pes?

,1 Packet +ata Traffic %&annel ,P+T%

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P+T% is used to trans it subscriber data in t&e packet switc&ing ode; and t&etrans ission rate ranges fro Cero to 22. /kbps. (ll P+T% s are unidirectional; eit&er uplink ,t&at is P+T% >9 used for t&e data trans ission for S to t&e GPRSnetwork or downlink ,t&at is P+T% >+ used for t&e data trans ission fro t&e GPRSnetwork to S .

,2 Packet Broadcast %ontrol %&annel ,PB%%

PB%% is to broadcast t&e necessar para eters resulted fro S access to t&enetwork because of packet ser7ices. Besides; it also broadcasts circuit switc&ingser7ice para eters; w&ic& &a7e alread been broadcast b B%% . S in t&e GPRS

(ttac& ode onl onitors PB%% ; and pa s no attention to B%% .

"f t&ere is PB%% in a cell; B%% will indicate it. T&at is to sa ; 7ia s ste essage;S"1# tells S t&at t&is cell &as alread been e5uipped wit& PB%% . "f t&ere is noPB%% ; B%% will broadcast para eters t&at will be used in t&e packet ser7ices.

,# Packet %o on %ontrol %&annel ,P%%%

P%%% includes t&e following t pes of c&annels?

Packet Paging %&annel ,PP% ? it is onl used in downlink to page S.

Packet Rando (ccess %&annel ,PR(% ? it is onl used in uplink tore5uest one or ore P+T% s.

Packet (ccess Grant %&annel ,P(G% ? it is onl used in downlink toassign one or ore P+T% s.

Packet Notification %&annel ,PN% ? it is onl used in downlink to notifS of point-to- ultipoint ulti-pat& trans ission ,PT - calling.

"f t&ere is no P%%% in a cell; packet ser7ices infor ation can be trans itted 7ia%%% . "f t&ere is P%%% ; circuit switc&ing ser7ices infor ation can be trans itted7ia P%%% .

,$ Packet +edicated %&annel

Packet dedicated c&annels &a7e t&e following t pes?Packet (ssociated %ontrol %&annel ,P(%% ? bidirectional; used totrans it packet signaling in t&e data transport process.

Packet Ti ing ad7ance %ontrol %&annel 9plink PT%% >9? it is used totrans it rando access pulse so as to esti ate t&e ti ing ad7ance of

S for packet ser7ices.

Packet Ti ing ad7ance %ontrol %&annel downlink ,PT%% >+ ? it isused to renew trans ission ti ing ad7ance infor ation for se7eral

Ss. 8ne PT%% >+ corresponds wit& se7eral PT%% >9s.

T&e P%9 of uawei Tec&nologies %o; 4td. can support all packet c&annel functions.

''. Packet ogic Channel Combination Types

T&e co bination t pes include?

PB%% E P%%% E P+T% E P(%% E PT%%

P%%% E P+T% E P(%% E PT%%

P+T% E P(%% E PT%%

W&ere P%%% F PP% E PR(% E P(G% E PN%

W&en a cell is re5uired to be e5uipped wit& PB%% ; t&e first t pe will be adopted;and one cell can onl &a7e one c&annel co bination of t&is kind. W&en t&ere are5uite a few Ss in a cell and t&e P%%% is relati7el bus ; one or se7eral c&annelco binations of t&e second t pe can be added. 8nl w&en t&ere e=ists c&annel of t&efirst co bination t pe can e=ist t&e c&annel of t&e second co bination t pe in a cell.

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%&annels of t&e t&ird co bination t pe are ainl used for uplink and downlinkpacket data trans ission. Dac& cell can be e5uipped wit& one or se7eral c&annels of t&is co bination t pe.

T&e GPRS P%9 s ste of uawei Tec&nologies %o; 4td. supports all of t&e c&annelco bination t pes; w&ere t&e t&ird t pe can be di7ided into fi=ed P+% and d na icP+% . T&e fi=ed P+% is speciall used for GPRS packet data transport; and cannotbe forcefull occupied b circuit-switc&ed ser7ices; w&ile t&e d na ic P+% cand na icall switc& fro T% and P+T% according to ser7ice re5uire ents. "t isT% in t&e initial state of t&e s ste ; and it will switc& to P+% w&en t&ere is packetser7ice de and; w&ile it will switc& fro P+% to T% w&en t&ere is circuit ser7icede and.

'''. The %apping from ogic Channel to Physical Channel

GPRS packet c&annel adopts '2 ultifra e structure; and eac& packet c&annel &as'2 ultifra es. D7er four fra es constitute a radio block. T&erefore; eac& wirelessc&annel can be di7ided into 12 radio blocks and four idle fra es. "ts structure iss&own as in !igure 11-$.

B3 B1 B2 - B# B$ B' - B) B* B/ - B0 B13 B11 -

B3 B11H I12 radio blocks -? idle fra es

Figure 11-4 +ireless C'annel Structure

w&ere?

PB%% c&annel? it can be apped to suc& radio blocks as B3; B#; B);and B0. T&e specific nu ber is deter ined b t&e bus degree of itsbroadcasting c&annel; and t&e apping se5uence is in confor it wit&t&e abo7e- entioned order.

P%%% ? P(G% and PP% can ap to an radio block of t&edownlink c&annels e=cept t&e one occupied b PB%% . PR(% is t&euplink fra e corresponding wit& t&e radio block occupied b PB%% ;P(G% ; PP% ; etc.

P+T% ? it can ap to all t&e radio blocks; and it is used for packet datatrans ission.

P(%% ? it can ap to all t&e radio blocks; and it is used to trans it t&ewireless signaling of t&e air interface.

PT%% ? t&e 12 t& and #/ t& uplink fra e of eac& '2 ultifra e is aPT%% uplink c&annel; and t&e 12 t& and #/ t& downlink fra e of twoconsecuti7e '2 ultifra es constitute a PT%% downlink c&annel.

1.1. Packet /ccess %o$eW&en data transport occurs in t&e upper la er of S; t&e R4%> (% of S will initiatet&e packet access. S packet access ainl includes t&e following t pes? s&ortaccess; one-p&ase access; two-p&ase access; single block wit&out establis&ing TB!access; paging response; cell renewing; and obilit anage ent.

W&en t&e data to be trans itted are less t&an eig&t R4% blocks; t&ec&annel re5uest t pe of S will be s&ort access; w&ere &e nu ber of data packet will be deter ined b %S-1 coding.

W&en t&e data to be trans itted are ore t&an eig&t R4% blocks; andt&e R4% ode is re5uired to be t&e confir ed ode; t&e c&annelre5uest t pe of S will be one-p&ase access or two-p&ase access.

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"f w&at is to be trans itted is t&e S easure ent report; t&e c&annelre5uest t pe is single block wit&out establis&ing TB! access.

Besides; t&e c&annel re5uest t pe also includes paging response; cellrenewing; and obilit anage ent. owe7er; t&is kind of c&annelre5uest t pe is often treated as one-p&ase or two-p&ase access.

!or s&ort access and one-p&ase access; S will be assigned wireless resourcesonce and for all suc& as T!"; d na ic assigned 9S! or fi=ed assigned radio block bittable; etc. T&en S begins trans itting data. !or two-p&ase access c&annel re5uest;for t&e first ti e onl one radio block will be assigned to S; and S trans its packetresource re5uest infor ation 7ia t&e single assigned radio block. (fter t&at; S willundergo resource assign ent ,including T!"; 9S!; or radio block bit table for t&esecond ti e; and S begins trans itting data 7ia t&e assigned resources. Becauset&e packet c&annel re5uest is onl t&e eig&t-bit or ele7en-bit access pulse; t&e carriedinfor ation is 7er little; w&ereas t&e packet resource re5uest is a R4%> (%signaling packet coded b %S-1. T&erefore; it carries co parati7el uc& oreinfor ation including T44" of S; t&e ultiple ti e slot capabilit of S; wirelesspriorit ; etc. ; w&ic& is of benefit to t&e proper resource assign ent for S.

T&e s ste of uawei Tec&nologies %o.; 4td. supports all t&e access t pes; w&eresuc& access t pes as paging response; cell renewing; and obilit anage ent willbe treated as two-p&ase access treat ent.

1.1.0 Paging Processing

"n t&e GPRS>GS s ste ; paging includes packet paging and circuit paging; w&ic&will be introduced in t&e following.

'. Packet Paging

W&en t&ere is downlink data to be trans itted to S; SGSN s&ould initiate packetpaging to accuratel locate S. T&e paging re5uest essage initiated b SGSN willbe sent to P%9 7ia Gb interface; and P%9 will transfor it into packet paging re5uestto be trans itted 7ia 9 interface. "f t&ere e=ists P%%% in t&e BSS s steconfiguration; t&e re5uest essage trans its directl 7ia PP% . "f t&ere is no P%%%in t&e BSS s ste configuration; P%9 will send t&is essage to BS% 7ia Pbinterface; and BS% will trans it it 7ia P% .

(fter S recei7es t&e packet paging essage; it will initiate uplink te porar blockflow ,TB! to establis& a procedure; and t&en send to P%9 t&e paging responsepacket as data ode 7ia air interface. P%9 t&en transfers it to SGSN. (fter SGSNrecei7es t&e paging response; wit&in a certain processing period; t&e downlink datawill be able to be trans itted.

''. Paging Co-or$ination

"n t&e GS network; w&en a circuit call reac&es t&e S% w&ic& is e=pected to locatea certain subscriber; S% deter ines t&e location area t&e S &as registered in; andsends t&e circuit paging essage to all BS%s in t&is location area.

"f t&ere e=ists Gs interface between SGSN and S%; t&e GPRS>GS s ste will berun in t&e Network 8peration ode 8ne. T&e circuit paging of t&e GS ser7ice canbe sent 7ia GPRS packet c&annelT&at is to sa ; if an S is alread GPRS attac&ed;its circuit paging will go t&roug& Gs interface and Gb interface; and reac& SGSN 7ia

S%; and t&en reac& P%9 7ia SGSN. P%9 deter ines w&ic& c&annel will be used for t&e trans ission.

"n Network 8peration ode 8ne; if t&e S &as been assigned P+% ; t&en P(%%will be used for t&e trans ission. "f no P+% &as been assigned; and t&e s ste &asbeen configured wit& P%%% ; t&en PP% will be used for t&e trans ission. "f no

P+% &as been assigned and t&e s ste &as not been configured wit& P%%% ; t&en

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P%9 transfers t&e paging essage to BS% 7ia Pb interface; and BS% will trans itt&is circuit paging 7ia P% .

"f t&ere is no Gs interface between SGSN and S%; and t&e GPRS>GS s ste canonl run in t&e Network 8peration ode Two and T&ree; t&e circuit paging essagewill be trans it 7ia %%% .

S connects to R(% on t&e reception of t&is circuit paging essage; and initiatescircuit connection establis&ing process. "f t&e S is currentl engaged in t&e GPRSser7ice; it will initiate GPRS S9SPDN+ process to suspend t&e GPRS ser7ice. T&e

S will not resu e t&e GPRS ser7ice until t&e circuit is released.

T&e P%9 of uawei Tec&nologies %o.; 4td. supports t&e abo7e- entioned packetpaging and circuit paging functions.

1.1. Discontin"o"s Reception 2DR34

"n order to reduce t&e power consu ption w&en t&e S is idle; S s&ould adopt+R . T&e S supporting +R onl recei7es t&e paging essage ,packet paging andcircuit paging fro its corresponding paging group in t&e paging c&annel; w&ereast&e S not supporting +R &as to interpret all t&e paging essages in t&e pagingc&annel. 8b7iousl ; S will greatl reduce its power consu ption if it can support+R . T&e algorit& adopted b S to deter ine t&e paging group is t&e sa e wit&t&at of P%9 or BS%.

+uring t&e S (TT(% >GPRS (TT(% process; it s&ould be infor ed w&et&er t&eGPRS>GS network supports +R and t&e ot&er +R para eters or not.

1.1.5 ,ireless Reso"rce Distrib"tion

'. %e$i"m /ccess Control %o$e

T&ere are t&ree kinds of ediu (ccess %ontrol , (% odes? fi=ed distribution;

d na ic distribution; and e=tended d na ic distribution.!i=ed +istribution

T&e radio block used b t&e S &as been allocated b P%9 before &and. "f t&e radioblock &as been used up and t&ere are still data to be trans itted; P%9 &as todistribute radio blocks for a second ti e.

+ na ic +istribution

T&e radio block used b t&e S &as been allocated b P%9 te poraril . W&en P%9distributes radio resources to S; it will assign S se7eral wireless c&annels and t&euplink state flag ,9S! 7alue for eac& wireless c&annel. (fter t&e S recei7es t&eassign ent essage; it will onitor t&e 9S! 7alue of t&e downlink radio block of t&eassigned c&annel. "f t&is 7alue is t&e sa e wit& t&e assigned 9S! 7alue; t&en S willtrans it data in t&e corresponding uplink radio block.

D=tended + na ic +istribution

T&e resource distribution ec&anis is t&e sa e wit& t&at of d na ic distribution.T&e onl difference lies in t&at t&e nu ber of ti e slot used b t&e S a e=ceed its

ultiple ti e slot capabilit . (fter S recei7es t&e 9S! 7alue of one of t&e c&annels;it can trans it data in t&is c&annel and t&e ot&er c&annels wit& a bigger nu ber.

T&e BSS s ste of uawei Tec&nologies; %o.; 4td &as realiCed t&e d na icdistribution function. "t can c&oose (% ode according to t&e subscriber configuration wit&in t&e cell or t&e TR range.

''. % %"ltiple Time lot Capability

T&e ultiple ti e slot capabilit of S can be di7ided into 20 grades; w&ic& can bereferred to DTS" GS 3'. 32 Standard. S wit& different grade a &a7e different

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nu ber of packet c&annels t&at can be used concurrentl . W&en P%9 distributesradio resources to S; it s&ould take into consideration t&e S data trans ission5uantit ; t&e re5uired 5ualit grade of ser7ices; a7ailable wireless c&annels; etc. T&e

S ultiple ti e slot capabilit s&ould tr to be satisfied w&ile obser7ing t&e principleof aking full use of wireless resources.

T&e P%9 s ste of uawei Tec&nologies at present supports S wit& 1 12 gradeultiple ti e slot capabilit ; and can ake t&e best resource distribution based on t&eS ultiple ti e slot capabilit and t&e radio resources.

1.1.6 Packet ystem %essage

T&e packet s ste essage is ainl used to broadcast t&e para eters necessarfor S to access network because of ser7ice de and in a cell. W&en t&e cellsupports t&e GPRS ser7ice; B%% s&ould add new S"1# essage. 8t&erwise; S"1#

essage will not be broadcast if GPRS is not supported. T&e cell can be configuredwit& PB%% ; or not be configured. S will be notified w&et&er t&ere is PB%% in t&ecell 7ia S"1#. PB%% ainl broadcast t&e packet s ste essage dedicated to t&e

GRPS ser7ice.T&e packet s ste essage includes t&e following t pes? PS"1; PS"2; PS"#; PS"#bis;PS"$; PS"'; and PS"1#.

PS"1 ainl includes infor ation like cell selection; PR(% control;;control c&annel description; and power control para eters.

PS"2 ainl includes reference fre5uenc list; cell allocation table;GPRS obile allocation table; and P%%% description.

PS"# ainl includes t&e B( table of t&e adJacent cells; ser7ingcell>nonser7ing cell selection para eters; etc. PS"#bis ainl includest&e B( table of t&e adJacent cells; nonser7ing cell selection para eters;etc.

PS"$ ainl includes t&e P+% list used in t&e S easure ent in t&eser7ing cell.

PS"' ainl includes easure ent report; network control cellreselection infor ation; etc.

PS"1# is t&e sa e as t&e S"1# w&ic& is broadcast 7ia t&e B%% ; and itainl includes t&e access-related infor ation w&ic& is uni5ue of t&e

GPRS cell.

PS"1 PS"$ can be broadcast bot& 7ia PB%% and 7ia P(%% . PS"' can bebroadcast onl 7ia PB%% . PS"1# can be broadcast onl 7ia P(%% . W&en t&ere isPB%% in a cell; t&e PS"1# essage t&en will not be broadcast 7ia P(%% ; w&ic&will &owe7er c clicall broadcast PS"1. W&en t&ere is no PB%% in a cell; P(%%can onl c clicall broadcast PS"1# essage.

T&e BSS s ste of uawei Tec&nologies; %o; 4td. can perfor t&e trans ission of allt&e s ste essages related to t&e GPRS ser7ice; and it can realiCe t&e controlretrans ission; fast retrans ission; low-speed retrans ission of t&e s ste

essages. "t can also control t&e s ste essage trans ission 7ia P(%% based ont&e PB%% >P%%% configuration of t&e cell.

1.1.17 Ra$io ink Control

Radio 4ink %ontrol ,R4% la er is ainl responsible for t&e 44%-P+9 packetdisasse bling and asse bling. "t uses a kind of slide-window protocol and ensurest&at data are trans itted between t&e corresponding la ers b e plo ing confir edor unconfir ed ode. T&e siCe of t&e GPRS R4% slide-window is )$.

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W&en confir ed ode is adopted; eac& trans itted data block of Te porar Block!low ,TB! needs t&e confir ation fro t&e recei7er. 8t&erwise; it &as to beretrans itted. T&e TB! cannot be released until all t&e data &a7e been trans ittedand t&e confir ation b t&e recei7er &as been recei7ed. W&en t&e unconfir ed odeis adopted; t&e trans itted data block needs no confir ation fro t&e recei7er. T&e

lost data or t&e error data can be replaced b filling bits. TB! can be released oncet&e data trans ission is finis&ed.

T&e P%9 s ste of uawei Tec&nologies; %o. 4td. supports bot& t&e confir ed andunconfir ed odes. "t can specif t&e uplink data trans ission R4% ode accordingto t&e S re5uest infor ation; and deter ine t&e downlink data trans ission R4%

ode according to t&e downlink 44%-P+9 packet t pe.

1.1.11 Channel Co$e an$ C Change Control

GPRS &as four t pes of c&annel coding odes. T&e trans ission rate and t&enu ber of trans itted R4%> (% packet b tes of eac& coding ode are as follows?

C'annel Co)i n( Mo)e R,C-MAC .ata *lock Si/e 0octets Rate 0kbps

CS 1 2 $3 &%CS 2 1 3 #CS $ 1%3 6CS # % 213 #

+ifferent c&annel code odes &a7e different trans ission rates and differentre5uire ent for air trans ission 5ualit . T&e &ig&er t&e trans ission rate is; t&e&ig&er t&e re5uire ent for trans ission 5ualit is. "n t&e data trans ission process;BSS can d na icall adJust c&annel code ode according to t&e c&anges of wirelesstrans ission 5ualit so as to realiCe t&e purpose of tr ing to i pro7e trans issionrate on t&e principle of aking full use of radio resources and guaranteeing t&etrans ission 5ualit .

T&e P%9 s ste of uawei Tec&nologies; %o.; 4td. at present supports four code

odes? %S-1 %S-$. "t can d na icall c&ange between t&ese four odes accordingto t&e wireless trans ission 5ualit .

1.1.1# Ra$io ink %onitoring

"n order to en&ance t&e trans ission efficienc in t&e GPRS s ste ; se7eral kinds of link onitoring et&ods &a7e been applied to t&e 9 interface. T&e P%9 s ste of

uawei Tec&nologies; %o.; 4td. &as realiCed t&e following kinds of link onitoringfunctions as specified in t&e protocol?

'. ink %onitoring in the (plink Dynamic Distrib"tion %o$e

W&en (% is in t&e d na ic distribution ode; P%9 assigns resources for eac& TB!

7ia 9S!. S deter ines its uplink usage rig&t b detecting its 9S! 7alue on t&eassigned c&annel. 8nce S detects its assigned 9S!; it will trans it data block ont&e corresponding uplink c&annel. "f t&e wireless link 5ualit is bad; and S cannotproperl recei7e its 9S! 7alue; it will not be able to trans it data block to t&e networkin t&e corresponding uplink block. (ccording to t&e protocol re5uire ent; P%9 detectst&e 7alidit of t&e links b onitoring t&e siCe of N#131. N#131 is initialiCed to be Cerow&en t&e TB! is establis&ed. P%9 eac& ti e assigns one block to one TB!. (fter t&at;it will e=pect to recei7e t&e infor ation of t&is TB!. "f no corresponding data block &asbeen recei7ed; t&en N#131 will be added one. +uring t&is process; once t&e S datablock is recei7ed; N#131 will return to Cero. "f t&e 7alue of N#131 reac&es its

a=i u 7alue N#131K a=; P%9 will acti7ate ti er T#1)0. W&en T#1)0 spills; TB!will be released; and t&e corresponding resources can be used again.

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''. Downlink %onitoring

!or t&e downlink TB!; P%9 assigns uplink signaling c&annel for S b setting t&eRRBP on t&e downlink data block. P%9 onitors t&is signaling c&annel 7ia N#13'counter so as to test t&e 7alidit of TB!. N#13' is initialiCed to be Cero w&en t&e TB!

is establis&ed. P%9 eac& ti e sets RRBP on downlink data block of TB!. (fter t&at; itwill e=pect to recei7e t&e control infor ation of t&is TB! on t&e corresponding uplinkblock. "f no corresponding data block is recei7ed; t&en N#13' will be added one. "f correct reception occurs; t&en N#13' will return to its original state. "f t&e 7alue of N#13' is larger t&an or t&e sa e as its a=i u 7alue N#13'K a=; P%9 willacti7ate ti er T#10'. 8nce T#10' spills; TB! will be released; and t&e correspondingresources can be used again.

'''. (plink Release %onitoring

P%9 ensures t&e nor al release of t&e uplink TB! 7ia #13# counter according to t&eprotocol. N#13# is initialiCed to be Cero w&en t&e TB! is establis&ed. (fter P%9 &ascorrectl recei7ed all t&e uplink TB! data; it will send Packet 9plink (ck>Nack ,!("F1indicates t&e last confir ation to S; and set RRBP in &ope t&at S will confir t&is

essage. "f P%9 does not recei7e correct packet control (ck>Nack infor ation in t&ecorresponding uplink block; t&en N#13# will be added one. "f N#13# e=ceeds t&epreset a=i u 7alue; P%9 will acti7ate T#1)0. W&en T#1)0 spills; TB! will bereleased; and t&e corresponding resources can be used again.

1.1.1* Ra$io &re8"ency Power Control

'. (plink Power Control

T&e P%9 s ste of uawei Tec&nologies; %o; 4td. pro7ides uplink open loop power control algorit& . T&e detailed for ula can be referred to in t&e DTS" GS 3'. 3/protocal. T&e basic idea of t&e open loop power control is t&at supposing t&e uplinkand t&e downlink &a7e t&e sa e pat& loss; S t&erefore can adJust t&e output power based on t&e recei7ed signal le7el. "n t&e GPRS cell t&ere will be S"1# essagebroadcast; in w&ic& e=ists a para eter na ed (4P (; w&ic& will be used b S tocalculate t&e output power 7alue of its uplink P+% ,P% . T&at is to sa ; t&e power 7alue actuall adJusted b S results fro t&e calculated adJustable power 7alue

ultiplied b t&e (4P ( coefficient. (4P ( ranges fro 3. 3 to 1. 3. (t present7alues e=cept 1. 3 are not used. T&e are reser7ed. W&en t&e 7alue is 3. 3; it eanst&at t&e &andset does not perfor power control.

''. Downlink Power Control

(t present; t&e P%9 of ost co panies does not support downlink power control.

"t s&ould be e=plained t&at t&e abo7e- entioned condition refers to t&at in w&ic&&andsets perfor packet data co unications. W&en 7oice co unication isneeded; it will return to t&e nor al GS control flow.

1.1.1+ Cell Reselection Control

'. Cell Reselection Network Control %o$e

T&ere are t&ree kinds of GPRS network control odes? N%3; N%1; and N%2. T&eeaning of eac& network control ode is as follows?

N%3? S perfor s cell selection auto aticall ; and does not sendeasure ent report.

N%1? S perfor s cell selection auto aticall ; and sendseasure ent report.

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N%2 network control? S sends easure ent report and accepts t&ecell reselection of t&e network control.

T&e BSS s ste of uawei Tec&nologies; %o.; 4td can deter ine network controlode according to t&e subscriber data configuration. (t present; N%3 ode is

supported.

''. Cell /"tomatic Reselection

S onitors t&e PB%% >B%% carrier of t&e adJacent cell at an ti e; anddeter ines t&e best cell to attac& based on t&e infor ation suc& as t&e carrier signalintensit ; t&e base station color code in t&e carrier; etc. eanw&ile; it infor s t&es ste of its own route area b initiating t&e route area update flow.

'''. Cell Change Control

S regularl sub its easuring report to BSS according to t&e cell s ste essagebroadcasting para eters. BSS takes full consideration of t&e S easure entreport; t&e load of eac& adJacent cell; etc. and sends cell c&ange co and to S;re5uiring t&e S to attac& to a specific cell.

1.1.1 &low Control an$ 9o G"arantee

'. &low Control

+ue to t&e different p& sical ediu and trans ission protocol between Gb interfaceand 9 interface; t&e trans ission rate of t&ese two kinds of interfaces is different.T&e trans ission rate of Gb interface is &ig&er t&an t&at of 9 interface. Besides; int&e downlink data trans ission; data trans ission 7ia 9 interface is li ited b suc&factors as S ultiple ti e slot capabilit ; wireless 5ualit ; a7ailable wirelessc&annels in t&e cell; etc. T&erefore; t&e trans ission rate is not constant; and t&edownlink data needs flow control.

"n t&e nor al work of a cell; t&e P%9 s ste s&ould acti7ate flow control progra ;and regularl reports t&e bucket siCe and bucket flow speed of t&is cell according tot&e wireless packet c&annel condition. eanw&ile; it also reports t&e bucket siCe andt&e bucket flow speed of S based on t&e S occupied wireless resource condition,t&e bucket of a cell refers to t&e a=i u packet data 5uantit sa7ed t&at t&is cellallows. "t c&anges as t&e nu ber of packet c&annels in t&e cell c&anges. T&e bucketof S refers to t&e a=i u packet data 5uantit t&is S allows. "t c&anges as t&enu ber of assigned S c&annels c&anges. T&e bucket flow speed refers to t&e datatrans ission rate . SGSN appropriatel adJusts t&e downlink data flow speed of t&ecell and eac& of t&e S according to t&e reported para eters so as to realiCe t&e flowcontrol on t&e downlink data.

T&e P%9 s ste of uawei Tec&nologies %o.; 4td. can realiCe t&e downlink data flowcontrol; and is able to regularl report t&e bucket siCe and bucket flow speed of t&eacti7e cell and t&e acti7e S to t&e SGSN. "t is also able to adJust t&e para eters tobe reported according to t&e cell packet resources and t&e 7ariation of t&e Soccupied resources.

''. 9o G"arantee

T&e 5ualit of ser7ice ,8oS of GPRS ainl includes t&e following inde=es? priorit ;dela grade; reliabilit grade; peak load grade; and a7erage load grade. Dac& inde=can be di7ided furt&er into se7eral grades. Because t&ese inde=es are t&e point-to-point re5uire ents for t&e entire packet data trans ission; and it in7ol7es anfactors like t&e air interface radio resources; Gb interface fra e rela link resources;GPRS backbone network trans ission bandwidt&; and 7arious kinds of GPRSe5uip ent processing capabilities; t&e 6oS re5uire ent is et all according to t&e

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Best Dffort grade at present. T&at is to sa ; data will be trans itted as soon aspossible according to t&e principle of aking t&e best use of resources.

Because ser7ices wit& different 6oS occup different s ste resources; and t&esubscriber ser7ice 5ualit is also different; carriers can differentiate subscribersaccording to t&e different 6oS grades and adopts fle=ible c&arge policies; w&ic& isbeneficiar for t&e spread of t&e GPRS ser7ice.

T&e P%9 of uawei Tec&nologies; %o.; 4td can assign S radio resources based ont&e radio priorit re5uired b t&e data trans ission; peak load grade; and a7erageload grade. T&e S wit& &ig&er radio priorit and &ig&er load grade will be grantedpriorit in t&e radio resources distribution. T&e 6oS re5uire ent will be et accordingto t&e Best Dffort grade.

1.1.10 %obility %anagement an$ Comm"nication %anagement

'. %obility %anagement

T&e obilit anage ent is used in P4 N ,Public 4and obile Network to support

t&e function of tracing t&e current location of S. T&e obilit anage ent functionof t&e GPRS network is si ilar to t&at of t&e current GS s ste . 8ne or se7eralcells for a route area ,a subset of a location area ; and one SGSN pro7ides ser7icesfor one or se7eral route areas. T&e S location tracing is deter ined b t&e S

obilit anage ent status.

GPRS obilit anage ent ainl includes GPRS (ttac&>+etac&; cell>route areaupdate; Joint route area>location area update; paging; etc. (fter an S acco plis&esGPRS (ttac&; SGSN will establis& obilit conte=t for t&e S and store t&e currentlocation and status infor ation of t&e subscriber. W&en t&e S roa s betweendifferent cells and route areas in t&e future; it will acti7ate cell>route area update flow;and SGSN will also store t&e latest infor ation of t&is S so as to realiCe t&e locationtracing for t&e S. W&en S perfor s suc& flows as Joint GPRS (ttac&>" S" (ttac&;

Joint cell>route area update; SGSN will co unicate wit& S% about S locationinfor ation 7ia Gs interface. "n t&is wa onl once obilit anage ent flow canrealiCe t&e S location tracing b t&e packet switc&ing ser7ice and circuit switc&ingser7ice. T&e detailed flow can refer to DTS" GS 3#. )3 protocol.

Because t&e la er-b -la er encapsulation feature of packet data; in t&e obilitanage ent all t&e flow signaling e=cept t&e paging flow is trans itted as data in

BSS. T&at is to sa ; BSS is onl related to t&e paging function of t&e obilitanage ent. (fter BSS gets t&e paging packet fro SGSN; it selects t&e necessar

infor ation and sends t&e paging infor ation 7ia t&e air interface.

''. Comm"nication %anagement

GPRS co unication anage ent ainl includes con7ersation anage ent;billing anage ent; etc. owe7er; because t&e upper la er signaling is trans ittedas packet data; BSS al ost does not participate in t&e con7ersation anage entprocess e=cept trans itting signaling data. "n addition; t&e billing infor ationcollection is ainl perfor ed in SGSN and GGSN. BSS does not participate in t&ebilling anage ent.

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1.# GPR Network Planning

1.#.1 GPR Capacity Planning

T&e 7oice traffic calculation alread &as ature ode; t&at is t&e Drlang table. Traffic,( ; c&annel nu ber ,N and call loss rate ,B &a7e t&e following relation. "f an twoout of t&e t&ree para eters are known; t&e t&ird one can be worked out b t&efollowing for ula.

B N =

A N

Ann.

T&e packet data traffic can not directl e plo t&e Drlang B table; w&ic& is due to t&euni5ue features of t&e packet data. T&e packet traffic of t&e fi=ed network &as acalculation solution; w&ic& is 7er difficult to be used in t&e obile en7iron ent.GPRS data traffic odel &as so et&ing to do wit& application occasions suc& asD ail; web browsing; online ga es; etc. +ifferent t pes of application &a7e differentdata 5uantit ; w&ic& is deter ined b t&e b te nu ber; packet nu ber; dela class;and ser7ice t pe.

'. The Calc"lation of "bscriber /verage /ccess Rate

"n t&e real application planning; t&e bus &our a7erage traffic for eac& subscriber s&ould be esti ated. Before t&e esti ation; we s&ould first esti ate t&e a7eragesubscriber access rate; w&ic& is deter ined b t&e %S1-%S2 ratio ,t&e GPRSc&annel coding at t&e initial stage generall e plo s %S1-%S2 ; subscriber


16/47


%S$; t&e nu ber of t&e 44% P+9 bits trans itted b eac& R4% datapacket is 23 b tes; #3 b tes; #) b tes; and '3 b tes respecti7el .

T&e protocol &eader of t&e !R; NS; BSSGP; 44%; and SN+%P of t&eGb interface is '# b tes.

T&e following for ula can be used to esti ate t&e a7erage data rate of t&e "P la er in7arious kinds of %S coding et&ods.

(1 > B

T , M3. 2 M3. 1 M23

@"P (2 > T

@Gb @"PM,1'3 '# > 1'3 1. #2* @ "PW&ere?

is t&e ini u R4% data block nu ber necessar to trans it n 44%P+9s

(1 is t&e total nu ber of all t&e b tes in n 44% P+9s

(2 is t&e total nu ber of all t&e b tes of n "P packetsB is t&e total nu ber of all t&e 44% P+9 b tes supported b eac& R4%data block

T is t&e ti e necessar to trans it n 44% P+9s; t&at is n "P packets

@"P is t&e esti ated "P la er carr ing rate of eac& P+%

@Gb is t&e esti ated carr ing rate at t&e Gb interface la er of eac&P+%

represents t&e upper round-off for ; w&ile represents t&e lower round-off for .

T&e result of t&e calculation is as follows?

CS 104bps

CS 204bps

CS04bps

CS # 04bps

5 interface p' sical la er spee) $3&% 1 3# 1%36 213#7P carrier spee) %3#2 "31# $3!! 1 36Carrier spee) nee)e) at t'e Abisinterface p' sical la er 16 16 2 2

Carrier spee) nee)e) at Gb interfacep' sical la er !31$ 1&3!$ 123$6 1"3&$

Suppose t&e proportion of t&e %S1 and %S2 in t&e designed network is 1?0. T&ea7erage "P la er rate per ti e slot in t&e network is?

'. $2 13L /. 1$ 03LF*. /)/:bps.

Suppose t&e future ainstrea S t pe is #E1; and t&e subscriber ultiple ti e slotcapabilit is e plo ed b )3L. T&e a7erage access rate for eac& subscriber will be *./)/ # )3LF1$. 1)2:bps.

''. The Calc"lation of "bscriber /verage Traffic

(t present; t&e esti ation for t&e subscriber a7erage data rate generall adopts t&efollowing et&od?

T&e fi=ed "P odel ,fro %&inaNet will be referred to; and wit& t&e consideration of t&e obile data c&aracteristics; t&e a7erage bandwidt& for eac& subscriber in t&eGPRS field can be worked out?

S F r1Mr2M,(MnMTMr#MR > #)33

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@ F S>( F r1Mr2MnMTMr#MR > #)33

w&ere?

S stands for t&e local network traffic

@ is t&e network bus &our subscriber a7erage traffic

( stands for local subscriber nu ber

n stands for t&e a7erage network access ti es of a subscriber in aont&

T stands for t&e a7erage co unication duration eac& ti e

r1 stands for t&e bus da concentration coefficient; w&ic& refers to t&epercentage of t&e traffic in t&e busiest da agaist t&e traffic in a w&ole

ont&. "t &as not&ing to do wit& t&e ser7ice t pe; and usuall is set tobe 1>23 or so.

r2 stands for t&e bus &our concentration coefficient; w&ic& refers to t&epercentage of t&e traffic in t&e busiest &our agaist t&e traffic in a w&oleda . "t &as uc& to do wit& t&e ser7ice t pe.

r# stands for idle-seiCure ratio; w&ic& refers to t&e ratio between t&edata downloading period and t&e w&ole online period. "t is set to be 1>$.

R stands for t&e subscriber access rate

(ccording to t&e abo7e et&od; %&ina obile &as conducted an esti ation on t&ea7erage traffic for eac& GPRS subscriber during 2331-2332; and t&e result is 1/3bps.

(fter t&e a7erage traffic for eac& subscriber &as been esti ated; it will not be &ard for us to plan t&e capacit of t&e w&ole network.

1.#.# GPR Coverage Planning

T&e co7erage area of t&e GPRS is deter ined b t&e c&annel coding sc&e e. "n acertain co7erage area; D>N is a restriction factor. !or interference restriction areas; %>"is t&e aJor restriction factor.

"n t&e GPRS s ste ; 7arious GPRS 7oice c&annel correction coding sc&e es s&ouldbe in confor it wit& standard re5uire ent.

B4DR,Block Drror Rate F13L

"n t&e condition t&at B4DRF13L; t&e re5uired %>" 7alue &as been worked out bsi ulating t&e four GPRS c&annel coding sc&e es ,%S1; %S2; %S#; %S$ in so ereference. T&e si ulation condition ai s at t&e R4%> (% la er. T&e result is s&ownin Table 11-1?

Table 11-1 GPRS Channel Coding S heme!C"#

C'annel Co)in( C-7 0)*8 wit' 9: C-7 0)*8 wit'out 9:CS 1 !3 1 1&3 "CS 2 113 % 123 "CS 1 3 6 1 3 !CS # 2&3 " 1!3 2

T&e co7erage area esti ation still adopts 8ku ura- ata odel ,for t&e distancelonger t&an one kilo eter and Walfis&-"kega i odel ,for s all base stations .

Suppose t&e interference in t&e ser7ing area is constant and t&ere is no fre5uenc&opping; it stands for t&e ser7ing area in different c&annel coding condition.%o pared wit& 7oice and circuit-switc&ed data subscribers; it t&eoreticall refers tot&e ser7ing area w&en t&e %>" is 0dB.

Table 11-2 The Per entage of the Ser$ing %rea &ith the GPRS Channel Coding Com'ared &ith (oi e Subs riber Ser$ing%rea )*+

C'annel Co)in( ;kumura :ata +alfis' 7ke(ami

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CS 1 !$ "&CS 2 61 6CS %# %!CS # # !

T&e c&annel coding sc&e e of data subscribers based on circuit-switc&ingcorresponds to $. /kbps and 0. )kbps. We can co pare t&e wit& t&e 1$. $kbpsGPRS data subscribers ser7ing areas. !or t&e 7oice ser7ing area; t&e GPRS 1$.$kbps data subscriber ser7ing area reduces to /'LA for t&e 0. )kbps circuit-switc&eddata subscribers; GPRS data subscriber ser7ing area reduces to 02L. !igure 11-'illustrates t&e co7erage of 7arious GPRS c&annel coding.

cs- 2cs-1

cs-#cs-$

Figure 11-, GPRS


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!igure 11-* illustrates t&e relations&ip between %>" distribution probabilit and GPRSload. T&e cur7e also s&ows t&at %>" decreases wit& t&e increase of t&e GPRS load.8n t&e ot&er w&en t&e %>" is 0dB; t&e co7erage rate falls fro 03L to /)L.

Figure 11-. T'e relations'ip between C-7 )istribution an) GPRS loa) 0& 1&&>

!igure 11-/ illustrates t&e relations&ip between %>" and ultiple=ing factor; w&ere kranges fro se7en to nineteen. kF* is not t&e best condition for t&e GPRS. T&ebigger t&e ultiple=ing factor is; t&e ore powerful it will be to support co parati7el&ea7 GPRS load.

9i(ure 11 " T'e relations'ip between nonco=era(e rate an) 4 0GPRS loa) from & 1&&>

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1.#.* GPR &re8"ency Planning

T&e GPRS network fre5uenc planning s&ould consider t&e network data rate.+ifferent c&annel coding sc&e es s&ould be adopted for different data rates. Oust asw&at &as been entioned abo7e; different c&annel coding re5uires different %>". T&efre5uenc ultiple=ing ode is deter ined b t&e re5uire ent for %>".T&e classical anal sis et&od can still be used in t&e stud of fre5uenc ultiple=ing

odes. Suppose t&e ser7ing cell is represented b t&e s etric regular &e=agonand t&e co-c&annel interference cell is calculated wit& t&e si= cells at t&e first la er.T&e following for ula can be worked out?

C I =

Q ,1

. Q = R = 0 N ,2

W&ere % stands for carrierA

" stands for co-c&annel interferenceA

g stands for pat& wireless trans ission factor; w&ose 7alue is often set to be 2 'A

+ stands for ultiple=ing distanceA

R stands for t&e cell radiusA

N stands for t&e nu ber of t&e cells in a ultiple=ing fa il .

T&e first for ula &as considered Ra leig& attenuation en7iron ent rat&er t&an t&eeffect of t&e log-nor al attenuation. %orrections wit& a certain dB will be ade to gett&e nu ber of fre5uenc ultiple=ing fa ilies re5uired b different c&annel coding int&e GPRS network.

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Table 11-3 GPRS Fre/uen 0 Multi'lexing Famil0

C'annel Co)in(Sc'eme C-7 T'res'ol) 0)* N

"re5uire ent in t&e design.

T&e fi=ed GPRS c&annels s&ould c&oose t&e fre5uencies w&ose ultiple=ing distance can eett&e %>" re5uire ent.

T&e GPRS c&annels w&ic& are not fi=ed s&ould start c&oosing t&e fre5uencies fro t&ose t&at&a7e longer ultiple=ing distance. %o pared wit& 7oice c&annels; t&e &a7e an option

ec&anis .

"mmary

T&e GPRS network planning s&ould tr to guarantee t&e 6oS of t&e e=isting 7oice ser7ices; andtr to reduce t&e unfa7orable effect on t&e 7oice ser7ices caused b t&e GPRS ser7ices. (t t&einitial stage; in order to si plif t&e network planning work; a location area can include onl onerouting area. (fter t&e GPRS ser7ice &as been de7eloped; a location area s&ould be di7ided intose7eral routing areas according to t&e geograp&ic distribution condition and GPRS ser7icedistribution condition.

!re5uenc &opping &as no ob7ious ad7antage for t&e GPRS ser7ice. "t can i pro7e t&e %S-1perfor ance; &as no ob7ious influence for %S-2>#; and lower t&e %S-$ perfor ance. (t t&e initialstage of t&e GPRS introduction; in order to a7oid network planning co ple=it ; t&e originalfre5uenc &opping para eters s&ould not be c&anged. "n order to ake full use of t&e GPRScoding tec&nolog ad7antage and to reduce t&e effect on t&e 7oice ser7ices; independentfre5uenc planning s&ould be taken for t&e GPRS network.

"t is reco ended t&at at t&e beginning onl t&e uplink power control be adopted; and t&edownlink power control be graduall introduced.

!re5uent c&ange of t&e c&annel coding et&od s&ould be a7oided. 8t&erwise; t&e concussioneffect will be present.

GPRS is a new planning subJect. T&e unsol7ed proble s re5uire furt&er stud in t&e future.

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,CD%/ ystem :verview

9ni7ersal obile Teleco unication S ste s ,9 TS is t&e t&ird generation obile

co unication s ste adopting t&e W%+ ( air interface. T&e 9 TS s ste is also calledW%+ ( co unication s ste . T&e 9 TS s ste uses t&e sa e structure as t&at of t&esecond generation obile co unication s ste . "t includes so e logic network units. +ifferentnetwork units can be di7ided into groups according to functions; or subnetworks t&e respecti7elbelong to.

!ro t&e functional 7iew; network units can be di7ided into radio access network ,R(N and corenetwork ,%N . R(N deals wit& t&e functions related to radio access; w&ile %N deals wit& all t&e7oice calls; data connection; t&e switc&ing and routing wit& t&e e=ternal networks wit&in t&e 9 TSs ste . T&e two units and user e5uip ent ,9D Jointl for t&e w&ole 9 TS s ste . "ts s stestructure is s&own as in !igure 11-0?

#G PS

S%H P @4RH QG S%H Qgs SS!#G %S PSTN

SGSN;GGSN

9TR(N

SERVI CEAPPLI CATI ON

HLR, SCP

R(N #G %N D TDRN(49D

"nternet

Figure 11- T'e S stem Structure of t'e 5MTS S stem

!ro t&e perspecti7e of t&e GPP R00 standard; 9D and 9 TS Terrestrial Radio (ccess Network,9TR(N &a7e co pletel new protocol co position; w&ose design is based on t&e W%+ ( radiotec&nolog . %N adopts t&e GS >GPRS definition; w&ic& can realiCe t&e s oot& transition of t&enetwork. Besides; at t&e beginning p&ase of t&e #G network construction; t&e global roa ing canbe realiCed.

(%T ystem Network Composition

9u lu

9S"

D

%u

Node B

Node B

Node B

Node B

RN%

RN%

lub lur

S%>@4R G S%

SGSN GGSN

4R

P4 N PSTN "S+N;etc

"NTDRNDT

;


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(ser ;8"ipment 2(;4

9D is t&e subscriber ter inal e5uip ent. "t ainl includes radio fre5uenc processing unit;baseband processing unit; protocol stack odule; and application la er software odule. 9Dtranscei7es data to and fro network e5uip ent 7ia 9u interface so as to pro7ide subscribers wit&

circuit-switc&ed or packet-switc&ed ser7ices including P8TS; broadband 7oice; obile ulti edia;and "nternet applications suc& as D ail; WWW browsing; !TP; etc.

9D includes two parts?

T&e obile D5uip ent , D pro7ides application and ser7ices.

T&e 9 TS Subscriber odule ,9S" is responsible for t&e identification of t&e subscriber identit

The (%T Terrestrial Ra$io /ccess Network 2(TR/N4

9TR(N can be di7ided into base station ,Node B and radio network controller ,RN% .

Node B

Node B is t&e base station of t&e W%+ ( s ste ,radio transcei7er ; w&ic& includes radiotranscei7er and baseband processing parts. "t can interconnect wit& RN% 7ia t&e standard "ub

interface to acco plis& t&e. 9u interface p& sical la er protocol processing. "ts aJor functionsinclude? spectru spread; odulation; c&annel coding; and dispread; de odulation; c&anneldecoding; and t&e utual con7ersion between baseband signals and radio fre5uenc signals.

Node B is co posed of t&e following logic function odules? R! transcei7ing a plification; radiofre5uenc transcei7ing s ste ,TR ; baseband part ,BB ; trans ission interface unit; and basestation control part.

Radio Network %ontroller ,RN%

RN% is radio network controller; ainl responsible for t&e connection establis& ent anddisconnection; &ando7er&ando7er; acro di7ersit co bination; radio resources anage ent; etc.T&e detailed functions are as follows?

,1 T&e function of s ste essage broadcast and s ste access control.

,2 T&e obilit anage ent function of &ando7er&ando7er and RN% transfer.,# T&e radio resources anage ent and control function of acro di7ersit co bination; power control; and radio load distribution.

CN Core Network

%N is responsible for t&e connection to ot&er networks and t&e co unication and anage entof 9D. T&e aJor function odules are as follows?

,1 @ S%>@4R

@ S%>@4R is t&e W%+ ( core network %S do ain function node. "t connects to 9TR(N 7ia "u%S interface; connects to e=ternal networks suc& as PSTN; "S+N; and ot&er P4 N 7iaPSTN>"S+N interface; connects to 4R>(9% 7ia %>+ interface; connects to @ S%>@4R or S %7ia D interface; connects to S%P 7ia %(P interface; and connects to SGSN 7ia Gs interface. T&e

aJor function of @ S%>@4R is to pro7ide %S do ain call connection; obilit anage ent;aut&entication; and encr ption.

,2 G S%

G S% is t&e gatewa node between W%+ ( obile network %S do ain and e=ternal networks."t is a selectable function node. "t connects to e=ternal networks suc& as PSTN; "S+N and ot&er P4 N 7ia PSTN>"S+N interface; connects to 4R 7ia % interface; and connects to S%P 7ia %(Pinterface. "ts aJor function is to acco plis& t&e inco ing and outgoing calling routing function of t&e @ S% functions.

,# SGSN

SGSN is t&e W%+ ( core network PS do ain function node. "t connects to 9TR(N 7ia "uKPSinterface; connects to GGSN 7ia Gn>Gp interface; connects to 4R>(9% 7ia Gr interface; connects

to @ S%>@4R 7ia Gs interface; connects to S%P 7ia %(P interface; connects to S % 7ia Gd

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interface; connects to %G 7ia Ga interface; and connects to SGSN 7ia Gn>Gp interface. T&e aJor functions of SGSN is to pro7ide PS do ain functions suc& as routing transfer; obilit

anage ent; con7ersation anage ent; aut&entication and encr ption.

,$ GGSN

GGSN is t&e gatewa GPRS support node. "t connects to SGSN 7ia Gn interface and connects toe=ternal networks ,"nternet >"ntranet 7ia Gi interface. GGSN pro7ides data packet routing andencapsulation between W%+ ( obile network and e=ternal data networks. T&e aJor function of GGSN is t&e interface function for t&e e=ternal "P packet networks. GGSN s&ould pro7ide t&egatewa function for 9D to access e=ternal packet networks. !ro t&e perspecti7e of e=ternalnetworks; GGS functions as all t&e subscribers< "P router of t&e addressable W%+ ( obilenetwork. "t needs to e=c&ange routing infor ation wit& e=ternal networks.

,' 4R

4R is t&e &o e location register of t&e W%+ ( obile network. "t connects to @ S%>@4R or G S% 7ia % interface; connects to SGSN 7ia Gr interface; and connects to GGSN 7ia Gcinterface. T&e aJor function of 4R is to pro7ide functions like subscriber signature infor ationstorage; new ser7ice support; and en&anced aut&entication.

:%C

8 % function entities include e5uip ent anage ent s ste and network anage ent s ste .

T&e e5uip ent anage ent s ste perfor s t&e independent network ele ent aintenance andanage ent; w&ic& include perfor ance anage ent; configuration anage ent; faultanage ent; billing anage ent; and securit anage ent.

T&e network anage ent s ste can realiCe t&e unified aintenance and anage ent for all t&enetwork ele ents in t&e network. T&e detailed functions also include perfor ance anage ent;configuration anage ent; fault anage ent; billing anage ent; and securit anage ent.

The e


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'"r 'nterface

"ur interface is between RN%s. "ur interface is a uni5ue interface of t&e 9 TS s ste . "t is usedfor t&e obilit anage ent of S in t&e R(N. !or e=a ple; in t&e soft &ando7er&ando7er between different RN%s; all t&e data of S are trans itted fro t&e working RN% to t&e candidate

RN% 7ia "ur interface. "ur is an open standard interface.'"b 'nterface

"ub interface connects Node B and RN%. "ub interface is also an open standard interface. T&isalso enables t&e RN% and Node B connected b "ub interface to be pro7ided b differente5uip ent anufacturers.

!asic Principle of prea$ pectr"m Comm"nication

Because t&e obile subscribers are e=pected to be rando l o7ing all t&e ti e; t&e ultipleaccess tec&nolog w&ic& can be used to differentiate and identif d na ic subscribers< address

ust be introduced in establis&ing t&e connection between t&e . "t is t&e sa e wit& t&e signal

ultiple=ing tec&nolog in t&e fi=ed co unications. "n fact; bot& of t&ese tec&nologies belong tot&e signal 5uadrature partitioning and designing tec&nolog . T&e difference lies in t&at t&e signalultiple=ing ai s at differentiating ultipat&; w&ile ultiple access tec&nolog ai s at

differentiating ultiple d na ic addresses. T&e ultiple=ing tec&nolog realiCes in base band or inter ediate fre5uenc part; w&ereas t&e ultiple access tec&nolog realiCes in radio fre5uenc . "t

akes use of t&e electronic wa7e radiated b t&e radio fre5uenc to identif d na ic obileaddresses. T&e fa iliar ultiple access odes include !+ ( and T+ (. W&en signals aredifferentiated b 5uadrature codes; it is %+ (. %+ ( &as two aJor t pes? +S-%+ ( and ti eslot coding>fre5uenc &opping. T&e 7i7id e=planation of +SK%+ ( is t&at t&e spectru is spreadb ultipl ing t&e positi7e negati7e binar base band data wa7e b t&e pseudo-rando positi7enegati7e binar wa7e wit& code snippet rate uc& &ig&er t&an t&e signal rate. (s far as energ isconcerned; wa7e spectru intensit is reduced to a 7er low le7el; w&ic& is si ilar to t&e noise. "nt&e +S-%+ (; all subscribers occup t&e sa e fre5uenc band and t&e sa e ti e slot. T&e

addresses are identified not b t&e 5uadrature para eters or t&e ti e slot; but b t&e self-correlation function of different address signal code groups.

T&e +S-%+ ( &as beco e t&e ost i portant ultiple access ode in #G. T&e +S-%+ (co unication is fre5uenc spread co unication. To be ore accurate; it s&ould be calledspectru spread co unication; because it is t&e signal spectru bandwidt& t&at &as beenspread. "t is a kind of broadband co unication s ste . "ts aJor feature is t&e signal codebandwidt& before t&e spread is far less t&an t&e spread code series ,c&ip bandwidt&.

Narrowban$ an$ !roa$ban$ Comm"nication ystem

,1 +efinition? suppose R stands for t&e rate of t&e signal code ele ent to be trans ittedA T standsfor t&e duration of signal code ele entA ! stands for t&e bandwidt& occupied for t&e trans issionof signal spread code series.

"f R TF! T 1; t&at is w&en !FR or !F2R; it is called ordinar narrowband co unication s ste ."n digital co unication s ste ; fre5uenc s&ift and p&ase s&ift all belong to t&e narrowbandco unication s ste .

W&en ! R; t&at is w&en !>RF13-13 ,13-)3dB ; t&en t&e s ste is broadband co unications ste .

,2 T&e broadband co unication s ste is realiCed b t&e narrowband co unication s ste7ia spectru spread. T&e %+ ( co unication s ste is a t pical broadband co unications ste .

The !asic Principle of prea$ pectr"m Comm"nication ystem

!ollowing t&e principle of co unication and t&e fa ous S&annon for ula of t&e infor ationt&eor ; %F! T lg,1E as is s&own in !igure 11-11?

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"n t&e for ula; ! stands for t&e fre5uenc -li it bandwidt&A

T stands for ti e-li it ti e slot; w&ic& is usuall set to be 1 in t&e co unication principleA

N stands for t&e power signal>noise ratioA

% stands for c&annel capacit .

T&is for ula s&ows a ti e-li it ,T ; fre5uenc -li it ,! ; power-li it ,S continuous w&ite Gausc&annel; w&ose capacit can be 7i7idl represented b t&e 7olu e; w&ic& is deter ined b t&ree

ost i portant para eters.

Figure 11-11 C'annel Capacit C

T&ese t&ree para eters !; T; and lg,1E N for s t&e 7olu e %. w&en t&e 7olu e is in7ariant; t&et&ree 7ariables can be utuall c&anged. T&e re7elation of t&is dialectical relations&ip facilitatesultiple new co unication ec&anis establis& ent. T&e spread spectru co unication is a

t pical e=a ple.

,# "n t&e obile co unications; N is t&e ost i portant contradiction. T&e i pro7e ent of S>Ncan be at an cost. S&annon for ula indicates t&at S>N can be i pro7ed b sacrificing fre5uencband !. W&en % is in7ariant; t&e increase of ! can reduce t&e recei7ing S>N t&res&old 7alue of t&erecei7er lg,1E . T&is is t&e basic principle of spread spectru co unication? bartering ! for S>N.

The %a=or Technical in$e


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G ,dB F13 lg,N ,dB . T&e processing gain will be represented b decibel.

,2 "nterference Tolerance

"t refer to t&e decibel 7alue of t&e interference &ig&er t&an t&e signal t&e input end of t&e recei7er can tolerate in t&e nor al working condition? = G [ LS +)1 lglg S / N OUT ] LS stands for t&eactual trans ission pat& loss ,dB A

e=plicitl s&ows t&e a=i u interference recei7ing 7alue ,in decibel allowed b t&e recei7er of t&e spread spectru s ste .

!or e=a ple;

"n t&e W%+ ( s ste ; t&e 12. 2kbps 7oice ser7ice re5uires t&e t pical 7alue of Db>No to be '.3dB or so for t&e base band de odulation. "n t&e condition t&at t&e code snippet rate is #./$ cps; t&e processing gain G is 13lg,#. /$ >12. 2k F 2'dB. T&erefore; F'dB-'dBF23dB; t&atis; %>" -23dB; w&ic& is far s aller t&an t&e GS re5uired %>" 0dB. T&e reason t&at t&e capacitof %+ ( is larger t&an t&e pre7ious cell s ste ainl is t&e lower re5uire ent for %>" and s&orter fre5uenc ultiple=ing distance; w&ic& is 1 1 ultiple=ing.

The %a=or /$vantages an$ Disa$vantages of prea$ pectr"m Comm"nication

(d7antages?

,1 Strong anti-interference capabilit ; and t&e larger t&e G is; t&e stronger t&e anti-interferencecapabilit is.

,2 !or digital co unication s ste ; t&e p& sical interpretation of t&e anti-interference capabilitof t&e spread s ste ?

P E f ( E / N 1) = f ( N 1 F FT ) = f (S / N FT )

"t illustrates t&at P E is in direct proportion wit& t&e power S>N and signal base !T. W&en P E isin7ariant; S>N is in in7erse proportion wit& !T. T&erefore; w&en !TF13-13 ; and P E is in7ariant;co unication can continue in 7er low S>N. T&at is to sa ; 7er strong interference is allowed.

,# "t &as good securit . No atter it is direct spread or fre5uenc &opping; after spread; it will besi ilar to w&ite noise. T&erefore; it &as a good securit perfor ance. +igitaliCed subscribers can&a7e furt&er encr ption.

,$ 4ow power spectru densit . Because t&e spread belongs to t&e broadband s ste ; t&e wider t&e fre5uenc spectru is; t&e lower t&e power spectru intensit will be. T&erefore; it &as goodconceal ent perfor ance. (t t&e sa e ti e; it &as little interference for ot&er co unications ste s and &u an bodies.

,' "t is eas to realiCe large capacit ultiple access co unication. Ti e and fre5uenc two-di ension address di7ision increases t&e nu ber of potential addresses. Strong anti-interferencecapabilit and low power intensit eans ore subscribers allowed for interference-li it s ste s.

,) "t is eas to realiCe accurate ti ing and distance easure ent. "t is suitable for t&e para etric7ariation c&annel wireless co unication. T&e spread s ste is ore likel to realiCe di7ersit

reception in 7arious for s and i pro7e t&e anti-interference capabilit .+isad7antages?

,1 "t will occup signal fre5uenc bandwidt&. T&e code series ,c&ip bandwidt& after spread is far wider t&an t&e infor ation code series bandwidt& before t&e spread.

,2 T&e s ste realiCation is co plicated.

,# "t is difficult to realiCe s nc&roniCation on ti e 7ariation c&annels.

,$ (t present; it is difficult to realiCe large capacit co unication due to t&e li itation of detectingt&e nu ber of address codes.

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ome of the >ey Technologies in the ,CD%/ ystem

,CD%/ Channel Co$ing cheme

T&e W%+ ( c&annel coding sc&e e includes t&e following parts? correcting coding>decoding

,including speed adaptation ; interlea7ing>deinterlea7ing; trans ission c&annel appingto>separating fro p& sical c&annel. Besides; so e ser7ice co binations a re5uire certaindegree of ser7ice ultiple=ing; w&ic& will also be e bodied in t&e design of t&e c&annel coder anddecoder.

!igure 11-12 illustrates t&at c&annel coding sc&e e is not erel a atter about correctionselection; codec algorit& ; and interlea7ing algorit& . "t is also in7ol7ed in t&e co unication wit&t&e &ig& la er essages; in t&e ac5uisition of ser7ice 5ualit instruction fro t&e &ig& la er; and int&e ac5uisition of ser7ice ultiple=ing ode so as to realiCe different coding and ultiple=ingsc&e es for different ser7ices and pro7ide 7arious kinds of ser7ice co binations in t&e &ig&estefficienc . "n order to get adapted to t&e trans ission in 7arious rates; t&e c&annel coding sc&e eincludes t&e rate adaptation function. T&e W%+ ( proposes a rate adaptation algorit& ai ing atadapting 7arious ser7ice rates to a standard rate.

%R% %&annel codingSpeed atc&ingand inner-fra e

crossing%R% %&annel coding

Speed atc&ingand inner-fra e

crossing

%R% %&annel codingSpeed atc&ingand inner-fra e

crossing

"nter reuse fra ecrossing

and p& sical c&annel

apping

Si

SJ

9

+P+%B1

+P+%B2

+P+%B4

+P%%B

8t&er bit control labels

TP% labels

Pilot labels

Figure 11-12 +C.MA C'annel Co)in( an) Ser=ice Multiplexin(

8f course; w&at deter ines t&e c&annel coding perfor ance is still its error control sc&e e. "n t&e

W%+ ( proposal; t&ere are t&ree kinds of forward error correction codes? con7olution code; Turbocode; and ser7ice specific code. T&e con7olution code follows t&e second generation tec&nolog .T&e restriction lengt& is 0; and t&e co on code rate is 1># and 1>2. T&e decoding is t&e @iterbialgorit& based on t&e a=i u likeli&ood. Turbo code is a new tec&nolog able to pro7ide&ig&er ser7ice 5ualit .

Turbo code is a new cascading recursion s ste con7olution code. "t is ade of two recursi7es ste con7olution ,RS% coders wit& t&e sa e structure; b t&e cascading of internal interlea7er.T&e aJor ad7antage of Turbo code is t&at a ong t&e (WGN c&annels; its error correctioncapabilit can be close to S&annon li it.

T&e abo7e anal sis s&ows t&at t&e con7olution coding and decoding tec&nolog si ilar to t&esecond generation obile co unication s ste is still used for low rate and low perfor ancere5uire ent in W%+ (; w&ile for &ig& rate and &ig& perfor ance re5uire ent; Turbo code codec

sc&e e will be used. (t present; Turbo code codec tec&nolog de7elops fast; and it &as de7elopedinto an !D% tec&nolog branc& including an kinds of codec et&ods.

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pace-time Co$e

Wit& t&e increase of obile subscribers; and t&e obile co unication ser7ice de and tendencfro ordinar 7oice ser7ice to ulti edia ser7ice; fre5uenc spectru resources beco e scarce.T&erefore; t&e pursuit for t&e &ig&est fre5uenc utiliCation ratio &as beco e a c&allenging proble

for t&e present and in t&e future. T&is c&allenge &as stirred people to de7elop &ig&l efficientcoding tec&nolog ; odulation tec&nolog ; and signal processing tec&nolog to i pro7e t&eefficienc of radio fre5uenc . T&e space-ti e code is one of t&e ost i portant solutions proposedin recent ears; ai ing at i pro7ing radio fre5uenc utiliCation ratio. "n t&e researc& of t&e space-ti e code; on t&e one +a-s&an S&iu; Oosep& . :a&n; G. +. Golden and !osc&ini &a7edone uc& work on t&e la ered space-ti e ,4ST codeA on t&e ot&er Tarok& fro (T T;based on t&e su ar of t&e pre7ious researc& on t&e trans ission di7ersit ; &as done so einno7ati7e researc& on t&e space-ti e code based on t&e trans ission di7ersit . (ll t&e anal sisand si ulation indicates t&at t&e utiliCation ratio of t&e two space-ti e codes abo7e- entioned canreac& 23-$3bps> C; w&ic& eans t&e can ac&ie7e good fre5uenc band utiliCation ratio. "t can beanticipated t&at t&e future obile co unication s ste featured b t&e space-ti e code will &a7ee=tre el large s ste capacit ; e=cellent co unication 5ualit ; and e=tre el &ig& fre5uencutiliCation ratio.

,1 4a ered Space-ti e %ode. T&e la ered space-ti e code is first proposed b !osc&ini. "tdi7ides t&e signal source data into se7eral sub data strea and perfor s coding and odulationindependentl . T&erefore; it is not based on trans ission di7ersit . T&e basic structure of t&ela ered space-ti e code is as follows? t&e trans itter &as n trans itting antennae; w&ile t&erecei7er &as recei7ing antennae , n . "n t&e trans itter data fro t&e c&annel coding will bedi7ided into n directions; and flow to n antennae. T&e recei7ing antennae at t&e recei7ing endsi ultaneousl recei7e t&e signals sent b t&e n trans itting antenna; and t&en perforde odulation; c&annel esti ation; and decoding. T&e la ered space-ti e code &as t&e followingfeatures?

,a n antennae use t&e sa e fre5uenc band. T&e sign is in s nc&roniCation. T&e sa econstellation grap& will be used.

,b T&e signals sent b n antenna are independent. T&is is w& t&e la ered space-ti e code is not

based on trans ission di7ersit .,c T&e total power of t&e trans ission unit antennae is constant; w&ic& &as not&ing to do wit& t&enu ber of t&e trans itting antennae n.

,d T&e single c&annel wit& &ig& SNR will be di7ided into n o7erlapping c&annels wit& low SNR soas to i pro7e t&e fre5uenc spectru efficienc .

,e T&e ad7antage of la ered space-ti e code is t&at w&en n; it can be pro7en t&at t&es ste capacit is al ost in direct proportion wit& t&e nu ber of t&e trans itting antennae n.

,f T&e c&annel gain between different recei7ing antennae &as no relations&ip.

,2 T&e space-ti e code based on trans ission di7ersit . "n obile co unication s ste ;di7ersit is one of t&e ost i portant et&ods to pro7ide reliable co unication. T&e ordinardi7ersit odes include? ti e di7ersit suc& as c&annel coding; interlea7ing; w&ic& are 7er

effecti7e for fast attenuation; but not effecti7e for slow attenuationA fre5uenc di7ersit suc& asspread spectru A and space di7ersit . ultiple antennae recei7ing di7ersit and trans ittingdi7ersit bot& belong to space di7ersit . "n t&e actual obile co unication s ste ; because of t&e li itation of S siCe; t&e batter energ ; and t&e as etr of edia ser7ices; t&e best odeis t&at t&e base station uses ultiple antennae to realiCe recei7ing di7ersit and trans ittingdi7ersit ; w&ile S s&ould not be re5uired to use ultiple antennae. Based on t&is; Tarok& andot&er people fro (T T; based on t&e trans ission dela di7ersit ; for all proposed t&e space-ti e code based on trans ission di7ersit . Generall ; t&e trans itting di7ersit is considered to bean i portant tec&nolog to en&ance t&e radio link perfor ance. T&e space-ti e code based ontrans ission di7ersit can be di7ided into Space-ti e block code and Space-ti e trellis codeaccording to different coding odes.

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?igh-spee$ Power Control

( t pical proble for t&e %+ ( network is t&e near and far effect. Because all t&e subscribers int&e cell use t&e sa e fre5uenc ; it is i portant for t&e w&ole s ste to ensure t&at e7ersubscriber uses t&e ini u power to trans it signals. T&e 5ualit of t&e power control ainl

deter ines t&e %+ ( s ste capacit . "t is also far ore co plicated t&an t&at of GS .T&epower control of GS onl considers signal strengt&; but t&e power control of %+ ( ust bebased on S>".

T&e power control of %+ ( includes forward and backward. T&e forward power control includeseasure ent report power control; D"B power control; and forward fast power control; w&ic& are

t&e t&ree forward power control algorit& graduall de7eloped. T&e power control rate de7elopsfro 2 ti es per second; to '3 ti es per second; to /33 ti es per second. "t beco es &ig&er and&ig&er; and t&e perfor ance is also beco ing better and better. T&e backward power controlincludes open loop and closed loop. T&e open loop eans t&at S based on t&e recei7ed power esti ates t&e necessar trans itting power. Because t&e attenuation feature of t&e forward andbackward links is different; t&e esti ation can onl get an a7erage trans itting power. T&etrans itting power of t&e backward c&annel s&ould be deter ined bot& b t&e esti ation resultand b t&e adJust ent of t&e closed loop power control. T&e closed loop power control eanst&at t&e base station Judges t&e trans ission 5ualit on t&e backward c&annel; and sends it to t&e

S to ake t&e trans itting power adJust ent.

R/>; Reception

"n t&e W%+ ( s ste ; t&e ulti-pat& propagation is no longer a negati7e factor. "nstead; it is anideal result; because R(:D recei7er can co bine t&e signals wit& t&e dela of at least 1 %&ip ,t&edata trans ission rate of t&e W%+ ( network is #. /$ bps; t&at is 1%&ipF3. 2) icroseconds;e5ui7alent to */ eters into useful signals. T&e working principle of t&e R(:D recei7er is t&at itde odulates se7eral signals wit& different ti e dela respecti7el ; and t&en algebraicallco bines t&e to i pro7e reception perfor ance.

%"lti-s"bscriber Detection Technology

"n t&e ear 10*0 and t&e ear 10/#; :. S. Sc&nedier and R. :o&no respecti7el proposed t&eulti-subscriber recei7er , ulti-subscriber detection idea; w&ic& eans realiCing t&e ulti-

subscriber detection wit&out ultiple access interference b aking use of ot&er subscriberparallel interferencesuppressor; ulti-group ulti-subscriber detector; t&e ulti-subscriber detector based on neuralnetwork.

T&e serial>parallel interference suppressor is de7eloped fro t&e traditional %+ ( detector. "t firstrestore interference signal and t&en takes out t&e useful signal. T&e idea is to arrange t&e

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de odulated subscriber signal into order b t&e signal intensit . T&at is to ake t&e signalintensit of t&e first subscriber greater t&an t&at of t&e second subscriber; and t&e rest can be doneb analog . (t first t&e nor al de odulation et&od will be used to de odulate t&e firstsubscriber


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The Receive ensitivity of the ,CD%/ ystem

Receiver ensitivity

"n t&e W%+ ( s ste ; sensiti7it is related to an inde=es suc& as ser7ice rate; noise

coefficient; and interference t&res&old. (ssu ing t&ere is '3L load?

!or 12.2kbps c&annel; t&e t pical 7alue of t&e uplink sensiti7it is -121dB ; w&ile t&at of t&edownlink sensiti7it is -11*dB .

!or 1$$kbps c&annel; t&e t pical 7alue of t&e uplink sensiti7it is -11$dB ; w&ile t&at of t&edownlink sensiti7it is -111dB .

!or #/$kbps c&annel; t&e t pical 7alue of t&e uplink sensiti7it is -111dB ; w&ile t&at of t&edownlink sensiti7it is -13/dB .

The Relate$ &actors of the Receiver ensitivity

1Recei7er sensiti7it is Jointl deter ined b recei7

network planning technology

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