Đồ án tốt nghiệp-NT Ngân

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Bo co thc tp tt nghip

H v tn: Nguyn Th Ngn

Lp: in t 8_K49 ti: HSDPA cho h thng UMTS

Ni dung cng

Chng 1: Gii thiu

1.1 Cng ngh WCDMA v tnh trng trin khai

WCDMA(wideband code division multiple access) l chun lin lc 3G song

hnh cng vi chun GSM. WCDMA l cng ngh nn tng cho cc cng ngh

3G khc nh l UMTS v FOMA.WCDMA c tp on EITS NTT DocomoNht bn pht trin ring cho mng 3G FOMA. Sau NTT trnh c t ny

ln lin hip truyn thng quc t ITU v xin cng nhn di danh ngha l mt

thnh vin ca chun 3G c tn gi IMT2000. ITU chp nhn v cng nhn

WCDMA l giao din nn tng cho UMTS. FOMA c NTT Docomo a vo

ng dng t nm 2001 v c coi l dch v 3G thng mi u tin trn th

gii.Mc d cng da vo nn tng WCDMA song FOMA li khng tng thch

vi UMTS.Tnh hnh trin khai:


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1.2 Tin trnh trin khai cng ngh v tiu chun ha HSPA, HSDPA.

HSPA (High-Speed Packet Access: Truy cp tc cao) l mt cng ngh

truyn dn khng dy ang c ng dng cho cc thit b thng tin di ng. Hin

HSPA c hn 130 mng ang hot ng trn ton cu v khong 50 mng ang

c xy dng. HSPA hin ang h tr tc d liu 14.4 Mbps cho ngxung (HSDPA) v 1.4 Mbps cho ng ln (HSUPA). Cng ngh ny gip tng

gp i dung lng mng v gim thi gian tr i vi cc dch v tng tc. Tnh

trung bnh, ngi s dng c th download vi tc nhanh gp 20 ln so vi kt

ni GPRS ang c cc nh khai thc ti Vit Nam cung cp hin nay. Trong

tng lai gn, HSPA s c nng cp ln Release 8 vi tc 42 Mbps cho

ng xung v 12 Mbps cho ng ln

Gii thiu HSDPA

HSDPA l mt phng thc truyn ti d liu theo phng thc mi. y

c coi l sn phm ca dng 3.5G. Cng ngh ny cho php d liu download


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v my in thoi c tc tng ng vi tc ng truyn ADSL, vt

qua nhng cn tr c hu v tc kt ni ca mt chic in thoi thng thng.

y l gii php mang tnh t ph v mt cng ngh v c pht trin trn c s

ca h thng 3G W-CDMA.

HSDPA c tc truyn ti d liu ln ti a gp 5 ln so vi khi s dng cng

ngh W-CDMA. V mt l thuyt, HSDPA c th t tc truyn ti d liu ln

ti 8-10 Mbps (Megabit/giy). Mc d c th truyn ti bt c dng d liu no,

song mc tiu ch yu ca HSDPA l d liu dng video v nhc.

HSDPA c pht trin da trn cng ngh W-CDMA, s dng cc phng php

chuyn i v m ha d liu khc. N to ra mt knh truyn d liu bn trong

W-CDMA c gi l HS-DSCH (High Speed Downlink Shared Channel), hay

cn gi l knh chia s ng xung tc cao. Knh truyn ti ny hot ng

hon ton khc bit so vi cc knh thng thng v cho php thc hin download

vi tc vt tri. V y l mt knh chuyn dng cho vic download. iu

cng c ngha l d liu s c truyn trc tip t ngun n in thoi. Song

qu trnh ngc li, tc l truyn d liu t in thoi n mt ngun tin th khng

th thc hin c khi s dng cng ngh HSDPA. Cng ngh ny c th c

chia s gia tt c cc user c s dng sng radio, sng cho hiu qu download

nhanh nht.

Ngoi HS-DSCH, cn c 3 knh truyn ti d liu khc cng c pht trin, gm

c HS-SCCH (High Speed Shared Control Channel knh iu khin dng chung

tc cao), HS-DPCCH (High Speed Dedicated Physical Control Channel knh

iu khin vt l dnh ring tc cao) v HS-PDSCH (High Speed Downlink

Shared Channel knh vt l chia s ng xung tc cao). Knh HS-SCCH

thng bo cho ngi s dng v thng tin d liu s c gi vo cc cng HS-

DSCH.


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Trong nm 2007, mt s lng ln cc nh cung cp dch v di ng trn ton th

gii bt u bn cc sn phm USB Modem c chc nng kt ni di ng bng

thng rng. Ngoi ra, s lng cc trm thu pht HSDPA trn mt t cng tng

nhanh p ng nhu cu thu pht d liu. c gii thiu l c tc ln ti3.6 Mbit/giy, song y ch l con s c th t c trong iu kin l tng.

Do vy, tc ng truyn s khng nhanh nh mong i, c bit l trong iu

kin phng kn.

Tnh hnh trin khai ca HSDPA

Theo s liu ca Nghip on di ng ton cu (GSA) cng ngh 3,5G (HSDPA)

chim n 69% trong tng s mng di ng. trn ton cu. Nu nh 2006, c 166

mng di ng h tr HSDPA ti 75 nc, th kt thc nm 2007, s nh mng s

dng cng ngh ny l 204, 89 quc gia. Cc nh mng trang b cng ngh ny

c phn b ti nhiu vng khc nhau trn th gii, Ty u (61 mng), tip l

Nam (35), ng u (34), Trung ng v chu Phi (20), chu M v vng

Caribbe (16).HSDPA ti nhiu vng c tc download ln ti 7,2 MB/giy, cn

bnh thng cng t t 800 KB/giy n 3 MB/giy. Tuy nhin, tc gia cc

mng cng khng u nhau. C ti 62% s mng c tc download cao nht l

3,6 MB/giy, trong khi ch c 21% s mng t 7,2 MB/giy.

GSA cho rng, s pht trin ca mng 3,5G nh hng n cc dch v bng tn

trn ton cu, nhiu nh mng ang thm HSPA (bao gm HSDPA v HSUPA).

S lng cc nh mng s dng HSPA ch mi bt u trong nm va ri, v ln

ti con s 26, ti 22 quc gia.

1.3Gii php dung lng v tuyn vi HSPA

Cht lng ca mt h thng v tuyn c xc nh thng qua vic cc chng

trnh ng dng c s dng thng qua mng v tuyn nh th no.Thut ng

kha c th xc nh cht lng cc chng trnh ng dng bao gm tc d

liu v thi gian tr mng. Cc chng trnh ng dng vn c th c n


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nhn vi tc bt chm vi vi chc kbps nhng yu cu tr phi thp, ging

nh kiu VoIP v cc tr chi hnh ng thi gian thc. Mt khc, thi gian ti

xung ca s lng ln cc file ch c xc nh bi tc d liu ln nht, v

thi gian ch khng ng vai tr g. GPRS Re99 cung cp 30-40kbps vi thigian ch l 600ms.EGPRS Re4 khng ch tng tc bt ln cao hn t 3-4 ln

m cn gim thi gian ch xung cn 300ms.Tc d liu v thi gian ch cho

php cho php cht lng cc chng trnh ng dng u n i vi cc chng

trnh ng dng di ng c s bao gm duyt giao thc ng dng khng dy(WAP)

v n ni (push to talk).

WCDMA cho php tc d liu l 384kbps vi thi gian ch l t 100-

200ms,n cng lm cho vic truy nhp Internet gn nh nhanh nht n kt ning dy thu bao s v cung cp cht lng tt i vi cc chng trnh ng

dng giao thc Internet tr thp.

HSPA t n tc bt 1-2Mbps trong thc t v c th ln n 3 Mbps trong

iu kin tt. HSPA cng lm cho thi gian ch mng gim xung di 100ms, v

ngi s dng cui cng c th c thng thc cht lng chng trnh ging

nh i vi cc kt ni ng dy DSL.Khng hoc ch c mt vi vic c yu

cu a cc chng trnh ng dng trn mng ti mi trng di ng. Ch yuHSPA l truy nhp bng rng vi kh nng lin mch v bao ph rng ri. Gii

php dung lng v tuyn t GPRS ti HSPA c minh ha trong hnh 1.9

HSPA hin ti ang c thit k to ra tc bt cao khng ch i vi cc

ng dng thi gian thc.Kt qu tnh ton trn hnh v ch ra,tuy nhin, HSPA

c th p ng dung lng hot ng cng nh l i vi cc chng trnh ng

dng c thi gian tr v tc bt thp nh VoIP. 3GPP Re6 v 7 cng ci

thin c hiu sut ca HSPA i vi VoIP v cc ng dng tng t khc.


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Hiu sut tri ph cao v dung lng t bo cao c yu cu p ng tc

bt cao hn v mt vi thit b mi vi cng nhng v tr trm gc hin ti. Hnh

1.10 minh ha cho dung lng t bo d tnh trn mt sector trn 5MHz vi

WCDMA, vi HSPA c s v vi HSPA c ci tin trong mi trng v m tbo.HSPA c s bao gm c mt anten nhn Rake trong thit b u cui v 2 an

ten nhnh a dng trong cc trm gc.HSPA ci tin th bao gm 2 anten iu

chnh di dng v b kh nhiu trong trm gc.Kt qu m phng ch ra rng

HSPA c th em li li ch v cht lng v dung lng. HSDPA c s c dung

lng t bo cao gp 3 ln ca WCDMA v HSDPA ci tin th c dung lng t

bo cao gp 6 ln WCDMA.

Hiu sut tri ph ca HSDPA ci tin b gii hn l 1bit/s/Hz/cell.Mc cithin dung lng ng ln ca HSDPA c d on l trong khong t 30%

n 70%.Dung lng HSPA khng ch thch hp i vi cc dch v i xng m

cn vi c dch v khng i xng vi tc d liu v dung lng ng xung

cao.

Chng 2. Khi qut v tiu chun ha HSPA

2.1 3GPP

3GPP l t chc chun ha cc cng ngh mng thng tin di ng t bo cho c

HSDPA v HSUPA v t c kt qu rt tt nh i vi bn pht hnh cng

ngh a truy cp phn chia theo m bng rng WCDMA. Hn th, 3GPP cn chu

trch nhim cho vic chun ha gii php ton cu v tc d liu ci tin v

h thng di ng cho h thng ton cu (GSM/EDGE).Nn ca 3GPP ngy nay

khi m cng ngh WCDMA ang c chun ha theo vic la chn cng ngh

k thut t cc khu vc khc nhau trong nm 1997.Theo , WCDMA c


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la chn mt vi khu vc nh l c s cho h thng thng tin di ng th h th

3, v tr thnh nguyn l cng ngh cho hot ng mt vi khu vc ln cn. Do

, n cui nm 1998, M, chu u, Hn Quc v Nht Bn la chn v to

ra 3 GPP. Trung Quc sau cng la chn.Mc u tin t c l vo cui nm 1999 khi Re99 c cng b, bao hm

c y cc c tnh k thut ca cc bn pht hnh WCDMA. Re4 pht

hnh vo u nm 2001.

Chu trnh ca cc phin bn thng ch l 1 nm vi vic cho php cc phin bn

ln hn th c c ly tn s gim i. iu ny cng cho php c c s ch

nhiu hn ti mc cn thit v ni dung bn pht hnh hn l s ra i cc

phin bn d liu cn thit. Phin bn5 ra i nm 2002 v phin bn 6 ra i nm

2004. c tnh k thut ca Re7 c chp nhn vo na cui nm 2006.2.1.1 S chun ha HSDPA trong 3GPP

Khi m bn pht hnh 99 ra i, HSDPA v HSUPA khng cn phi bn ci.

Trong sut nm 2000, trong khi va hiu chnh vi Re99 th cng ng thi lm

vic kt hp vi Re4, v d, TD-SCDMA, n tr ln hin nhin i vi s cn

thit ci thin truy nhp gi. a ra mt gii php, mt nghin cu c tnh kh

thi v HSDPA bt u vo thng 3 nm 2000.Cc cng ty nhn bt u cng

vic vi HSDPA l Motorola v Nokia t bn cung ng, cn pha bn hot ngth c BT/Cellnet, T-Mobile v NTT DoCoMo.

Vic nghin cu tnh kh thi c xc nh l cho TSG RAN vo thng 3 nm

2001 v cc kt lun c cng b ch ra nhng li ch r rt trong vic nghin

cu gii php ny. Trong cc vn nghin cu HSDPA, c s tho lun v vic


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lm th no ci thin vic truyn dn d liu gi ng xung trong Re99.

Vn a ra l vic truyn dn qua lp vt l v tin trnh c s BTS cng c

nghin cu cp n l iu ch v m ha,k thut thu nhn v truyn dn

nhiu nten, vn nhiu u vo nhiu u ra(MIMO) cng nh l vic la chncell nhanh nht (FCS).

Khi m Re5 c pht hnh 1 nm sau , vo thng 3 nm 2002, y r rng

c s hiu chnh c th lm vi HSDPA, nhng chc nng chnh vn l nhng

k thut ca lp vt l.Cng vic phn no b chm li v nhng hot ng

hiu chnh cn thit din ra song song i vi thit b u cui Re99 v mng

ang b chuyn ra. c bit l phng din giao thc, vic kim tra nhy cho

thy s cn thit hiu chnh chi tit v lm sng t vn k thut v y l vn i vi nhng thit b i trc Re99 v s bt u ca cc t chc thng mi

Chu u vo na cui nm 2002.

T nhng vn lin quan n HSDPA, khi nim MIMO vn cha th thc hin

c trong Re5 v th 6, m vn c em ra tho lun sau ny khi m y l

u im c gii thiu cho s ra i ca Re7.

2.1.2 Tiu chun ha HSUPA trong 3GPP

Mc d HSUPA l mt thut ng c s dng rng ri trn th trng, trongtiu chun ha 3 GPP cho HSUPA vn c thc hin di tn knh dnh ring

ng ln ci tin(E-DCH).Cng vic bt u vi s hiu chnh pha i vi

HSDPA, bt u vi vic nghin cu thut ng s ci tin ng ln cho knh

truyn dn dnh ring vo thng 12 nm 2002. T nhng bn cung ng nh

Motorola, Nokia, Ericsson l nhng cng ty tr ct bt u nghin cu trong 3

GPP.

S u t v cng ngh trong vic nghin cu HSUPA c ch ra trong hnh sau:


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Sau khi nghin cu chi tit v gii thiu v bo co vn nghin cu cho

thy nhng li ch r rng t s u t cng ngh. Bn bo co cng ch ra khng

cn phi khuch i in p khi s dng bc iu ch cao hn trong kt ni ng

ln trc tip, kt qu cng ch ra vic iu ch thch hp khng bao gm cc

cng vic nh hin ti.

Vn nghin cu kt thc vo thng 3 nm 2004, vi vic bt u ca 3GPP vilp vt l HARQ v k thut da vo node B i vi ng ln cng nh l di

TTI ng ln ngn hn. Do ,chi tit hnh thnh nhanh hn i vi DCH s

c a ra bn cnh cng vic ca 3GPP, nhng vic tho lun vn c a ra

di dng cc vn khc nhau trong Re6 ca 3GPP, da trn nhng pht hin

trong sut thi k nghin cu.

3GPP bt u cng vic vi tiu Ci tin ng ln FDD nhn mnh

cu trc HSUPA theo yu cu ca bo co nghin cu. Ni dung TDD vn chac tin trin g vo thi im ny nhng n bt u c thc hin trong

Re7.

Vo thng 3 nm 2005, nhng cng vic hon thnh cho cc chc nng v k

thut, cu trc s c chuyn i hiu chnh v bo dng. Trong sut nm


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2005,vic tho lun m cng nh cc yu cu thc hin c xc nh. Qu

trnh tiu chun ha 3GPP i vi HSUPA l mt v d c ch ra trong hnh 2.5.

Bc cui cng i vi HSUPA l hon thnh kh nng tng thch pha sau giao

thc, vi vic cho php gii thiu thit b trn th trng.


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`


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2.1.3 y mnh s pht trin ca HSUPA v HSDPA.

Trong khi HSUPA ang c thit lp th din ra s pht trin trong vic ci

tin Re6 HSDPA cng nh mt vi khu vc, c th nh:

Hiu qu ca nhng c tnh k thut i vi tnh nng u cui vi s a dng vb thu v nhng u im b thu s ch ra trong chng 11.

Ci thin phm vi ng ln vi ti u ha tn hiu quay li ng ln, s ch ra

trong chng 4.

S ci tin trong khu vc di ng HSDPA bng tn hiu nhanh hn v thi gian x

l ngn i, c m t chng 4.

i vi Re7, mt cng vic c xc nh l kt ni lin tip i vi nhng

ngi s dng gi d liu, vi vic gim bt bit trn u trong qu trnh phc v

m yu cu l gi nguyn kt ni nhng khng cn thit tip ni dng d liu.

Khi nim thut ng MIMO cng c a ra tho lun y trc vi nguyn l

l khi c hai hoc nhiu anten cng pht vi cc phn cui khc nhau dng thng

tin v sau li dng 2 hoc nhiu anten thu v u im ca qu trnh x l tn

hiu trong thit b u cui c th chia s c dng con khc nhau vi nguyn

l c m t trong hnh 2.6.


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Th thch chnh l chng minh c y l nh hng ca vic gia tng khuch

i vn cho php khi m to thnh ti khon bn thu thc hin c ci tin chy

trn Re6 hay nhng kh nng khc ci tin dung lng c a vo bn pht

v d nh vic i t cu hnh 3 thnh phn n cu hnh 6 thnh phn. Nhng ktqu khng nm trong d bo ca 3GPP khi mi trng macro-cell HSDPA v

MIMO dng nh khng mang li bt k li ch no v mt dung lng qua b

thu a dng v nhng u im ca n cc thit b u cui.

Cc cng vic lin quan n hot ng ca HSDPA v HSUPA bao gm c

chuyn mch knh(CS) v chuyn mch gi(PS), tr thc hin cuc gi-ang

c gi mc thp hn v thi gian chuyn t trng thi ngh sang hot ng

(Cell-DCH).Hu ht tt c cc bc trong vWCDMA vn c gi nguyn, btchp l cuc gi cs hay ps. Vic ci tin s c ch i vi vic s dng

HSDPA/HSUPA cng nh thit lp cuc gi thng thng. Cng vic ny s tp

trung u tin vo vic lm th no ci thin s thit lp mt cuc gi thoi

Re99 v s bt u cng nh phng php a vo i vi cc thit b tn ti.

By gi phi tp trung vo iu chnh ln hn m khng lm vic c vi thit b

tn ti, nhng li c tim nng cho vic ci thin bi v s thay i vi cc

thit b u cui cng c th c thc hin. iu c ngha l vic ci tin y s din ra Re7 vi cc thit b tt c vn .

2.2 Tham kho.


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Chng 3: Cc giao thc v cu trc HSPA

3.1 H thng qun l ngun ti nguyn v tuyn.

Chc nng qun l ti nguyn v tuyn vi HSDPA v HSUPA c rt ra t

nhng chuyn i so vi Re99. Trong Re99 vic iu khin k hoch u da

hon ton vo b iu khin mng v tuyn(RNC) trong khi trong trm c s hay

node B trong cng ngh 3GPP y chnh l iu khin cng sut lin kt chc


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nng. Trong Re99 nu nh c n 2 RNC xung quanh mi ni th s

c phn phi li. RNC cung cp_SRNC l ci ang c kt ni ti mng li

kt ni kia c th iu khin s i vi knh dnh ring DCH v n cng c

kt ni ti trm thu nhn c s BTS cng cho php iu khin knh chung(gingnh FACH).

Khi s sp xp dch chuyn ti BTS, y c mt s thay i trn ton b kin

trc ca RRM. SRNC vn s gi iu khin chuyn giao v y l mt im s

thch ng vi vic nh x i vi tham s cht lng dch v(QoS). Vi HSDPA,

vn ny rt n gin v y khng c chuyn giao mm i vi d liu

HSDPA, do khng cn chy d liu ngi s dng qua nhiu hnh trnh Iub v

giao din Iur v mc d HSDPA c truyn dn qua Iur trong quy trnh k thut,th vic s dng ca giao din Iur c th b ph hy bi vic thc hin nh v li

SRNC, khi m vic cung cp cell knh chia s ng xung tc cao(HSDSCH)

nm di mt iu khin khc RNC(CRNC). Vi Re99 iu ny khng b ph

hy ti bin vng RNC khi chuyn giao mm c s dng gia hai trm c s

di cc RNC khc nhau. Cui cng th din tin ca HSDPA c th c trnh

by bi ch mt RNC n.


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3.1.1 Kin trc giao thc phng ngi s dng HSDPA v HSUPA.

Chc nng c s ca cc lp giao thc khc nhau c hiu lc vi HSDPA v

HSUPA ging vi Re99. Kin trc c th c xc nh i vi tng phn phng

ngi s dng thc hin d liu ngi s dng v iu khin phn phng. Lp

RRC trong vic iu khin tng phn phng thc hin tt c cc tn hiu lin quan


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n vic cu hnh cc knh, thit b qun l di ng,.. iu ny c n t u cui

s dng v c ch ra thng qua kin trc giao thc trong hnh 3.3.

Giao thc chuyn i d liu gi (PDCP) c mt b nn tiu chc nng chnh

v n khng thch hp i vi cc dch v chuyn mch. iu quan trng ca vic

nn tiu l hiu khi no th tiu ca giao thc Internet khng c nn c th

l 2 hay 3 ln kch thc ca chnh trng ti gi thoi ca n.

Vic iu khin kt ni v tuyn(RLC) thc hin phn on v truyn dn li i

vi c d liu ngi s dng v d liu iu khin. RLC c th hot ng trong ba

ch khc nhau:

Ch trong sut, khi m khng c bit trn u c a vo lp RLC, v

d nh m thanh AMR, v khng th dng c khi m cc knh truyn

dn ca HSDPA v HSUPA c s dng.

Ch khng bo nhn, khi khng c vic thc hin truyn dn li lp

RLC. iu ny c s dng i vi cc yu cu m c th cho php vic


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mt mt vi gi, nh trng hp i vi VoIP, v khng th cho php s

thay i tr theo mc truyn li RLC.

Hot ng theo ch bo nhn, khi m vic phn phi d liu c thc

hin c m bo vi vic nhng ln truyn li lp RLC vi u vo yucu tt c cc gi u c phn phi.

Lp iu khin truy nhp trung bnh (MAC) trong Re99 tp trung vo nh x gia

cc knh lgic v thc hin quyn u tin ging nh la chn ca tc d liu

ang c s dng, v d nh vic la chn ca nh dng truyn dn ang c

a vo. Chuyn mch knh truyn dn cng l mt chc nng ca lp MAC.

C HSDPA v HSUPA u gii thiu nhng thnh phn mi trong kin trc. Cc

chc nng lp MAC i vi HSDPA v HSUPA c th hot ng c lp tronghot ng ca DCH Re99, nhng li chim mt account khp c gii hn ti

nguyn ca giao din. Hnh 3.4 mt t ton b kin trc giao din v tuyn i vi

HSDPA v d liu ngi s dng HSUPA, lm r giao thc mi phn phi vi

d liu ngi s dng. Tn hiu iu khin phng- xut hin trong hnh 3.4 c th

kt ni n gin n RLC v c th mang d liu qua DCH hay qua

HSDPA/HSUPA.


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i vi d liu ngi s dng, PDCP thc hin nn tiu IP. y c mt vi

PDCP v RLC y c ch ra trong hnh ch dn kh nng chy cc dch v

song song.

Chc nng sp xp trm BTS l mt chc nng lp MAC, v kt qu by gi yl mt giao thc mi y , MAC-hs(hs i vi tc cao) trong BTS. y l

mt phn trong kin trc giao thc phng ngi s dng trong hnh 3.5, n bao

ph HSDPA, k thut a vo, v vic nh v ca n trong cc thnh phn ca

mng. RNC gi li MAC-d(dnh ring) nhng ch chc nng gi li l chuyn

mch knh truyn dn nh cc chc nng khc v d nh vic sp xp v thc hin

u tin, c dch chuyn ti MAC-hs. Ch rng lp trn ca lp MAC c tn l

lp RLC vn gi khng i, nhng c mt vi ti u ha i vi cc dch v RT

nh l VoIP c gii thiu trong ch bo khng nhn(UM) trong Re99.


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Nh cp trong phn gii thiu, ngoi tr nu nh HSDPA gii thiu truyn

dn li lp vt l, th lp RLC vn thc hin truyn li c th hot ng lp vt l

b li hoc c bit th trong kt ni vi cc hot ng di ng khc ging nh

chuyn i cell HSDSCH phc v. iu ny ang gi thit ch bo nhn RLC

hot ng. Trong trng hp ca UM-RLC, vic truyn dn li lp vt l ch c

mt kh nng duy nht. Mt v d c th l cuc gi VoIP khi m truyn li lp

RLC t RNC c th qu chm.


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Vi HSUPA, y ging nh kiu mt lp MAC mi y c a n

BTS,nh ch ra trong hnh 3.6. Tuy nhin, y khng phi l ni duy nht m cc

u vo c lm thnh kin trc giao thc. Thit b u cui c mt lp MAC

mi y nh th, y l mt phn chc nng sp xp c chuyn ti nt B,mc d da trn thng tin iu khin t RNC v yu cu dung lng trc tip t

thit b ngi s dng UE ti nt B. y l ton b giao thc mi i vi RNC.

iu ny dn n chuyn giao mm HSUPA c nh hng n s nh v gi u

ra. Khi m d liu c nhn trn mt vi v tr BTS, y l mt kh nng khi

hot ng trong chuyn giao mm khi m cc gi t cc BTS khc nhau ti, nh l

sp xp ca cc gi khng c gi, v cho php vic sp xp li c thc

hin di vi dng gi n, th chc nng sp xp li yu cu c kt hp vib kt hp a dng macro trong MAC-es. Do chc nng phn phi khng theo

th t MAC-es mi m bo rng cc lp trn gi c cung cp trong sp xp

c pht i t thit b u cui. Cng c th vic sp xp c thc hin ti BTS,

v tr khng cn thit c th xut hin BTS c th phi c ch i vi cc

gi li cho n khi chng c th c xc nh l c thu chnh xc bi mt

BTS khc trong chu trnh hot ng.

Khng ging nh HSDPA, lp RLC trong HSUPA thc hin truyn dn li ccgi nu nh lp vt l li phn phi chnh xc chng sau s lng ti a ln

truyn li b vt qu hay kt ni vi cc bin c di ng.

3.1.2 S tc ng ca HSDPA v HSUPA trong giao din UTRAN.

Trong tc ng ca HSDPA v HSUPA trong giao din th thng tp trung tho

lun v tc d liu th cc giao din khc li yu cu khc v d nh an ten. i

vi giao din gia trm c s v RNC, giao din Iub, y tc d liu by gi

l ln hn so vi u cui Re99.


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Trong khi u cui ca Re99 hu ht l 384kbps, th tc d liu trn giao

din khc bao gm giao din Iups ti nt cung cp GPRS dch v(SGSN) mng li

gi, l bng s dng i vi v tuyn. Vi HSDPA tnh hnh chuyn i.

Thng qua giao din khng kh, ngha l Uu trong thut ng 3GPP, n c th t

n tc d liu l 14.4Mbps qua cc chu k ngn 2ms. iu ny khng c

ngha l tc d liu tng t c th s dng trn giao din Iub v Iu-ps i vingi s dng ring l. T v tr ngi s dng n, ti nguyn l thi gian v m

c chia s ti nhng ngi s dng khc nhau trong mt cell. Do tc

trung bnh i vi ngi s dng trong mt cell c ti r rng l thp hn. Hn

na tc cc i t n 10Mbps yu cu tnh trng v tuyn cc tt v n

khng ging l tt c ngi s dng trong cell u c th t tc d liu cao.

Do , lu lng trung bnh trong giao din Iub cng gim so vi tc t c

i vi v tuyn. Mt v d c miu t trong hnh 3.7, n ch ra mt so snh vi

Re99 384kbps ng xung v HSDPA i vi trng hp 7.2Mbps. ng

xung 384kbps c tc d liu bng nhau d tr trong tt c cc giao din v n

khng vt qu gii hn 384kbps. Vi HSDPA, tc nh ca giao din v

tuyn cung cp bi u cui trong v d l 7.2Mbps. Tc d liu cung cp qua


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giao din Iu-ps v Iub c th b gii hn, v d ti 1Mbps. Vic s dng cc b

m trong cc BTS khin cho n c th c tc nh i vi cc kt ni u

cui cao nh thit b u cui v dung lng BTS cho php, trong khi vic gi tc

bit ti a trn giao din Iub v Iu-ps trn ng vi tham s QoS thu nhn tphn chnh gi.

Cc b m trong BTS cng vi s sp xp m thi gian chia s ti nguyn- cho

php t tc nh cao hn i vi v tuyn so vi tc trung bnh trong

Iub/hs. B m truyn dn trong BTS cng yu cu dng iu khin c a

vo trnh trn b m. Trong cch ny, di iu kin k thut v tuyn tt

hn, ngi s dng c nhiu ti nguyn Iub hn. Nguyn l hot ng iu khin

dng c ch ra trong hnh 3.8.

Nhng ngi dng di iu kin v tuyn tt s c s phn phi Iub nhiu hn

cng nh d liu chuyn dch nhanh hn t im v tuyn. Cch khc, khi m b


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m bt u y dn n tnh trng v tuyn km i, th iu khin dng s chm,

dng d liu gim i vi loi ngi s dng(hnh 3.8).

i vi cc thnh phn mng v bn thn thit b u cui th vic s dng

HSDPA v HSUPA l nguyn nhn ca mt vi chuyn i, c bit trong lp vtl nh trong lp MAC v RLC. i vi im RLC th y l mt tc ng m

khng ch ko theo iu khin dng c ni n m cn c c s chuyn i

RRM. Cc bin c di ng gy nn mt vi chuyn i trong u vo dn n c

hi chia s ti nguyn Iub ng gia nhng ngi s dng. Hn na tc d

liu tng t thc t ti a l 384kbps i vi thit b Re99 ln n 10Mbps v l

thuyt l ln n 14Mbps.

i vi cc BTS v thit b u cui, chuyn i chnh i vi HSDPA lin quann y vo ca s sp xp chc nng truyn li ti BTS c bit, chc nng kt

hp cc gi cn thit ti thit b u cui. Cc knh thm vo c yu cu i vi

bn thn truyn dn d liu hin thi, bao gm iu ch mi, ging nh mc ch

bo hiu to iu kin chc nng mi.

Tng t, vi HSUPA, cc chc nng mi c yu cu nh ch ra trong hnh

3.10. y, vic sp xp c iu khin bi BTS v chng l cc yu cu i

vi thc hin dng d liu trong ci khc nh cc knh bo hiu mi i viHSUPA. Cc chc nng kt hp trm gc v chc nng sp xp li mi c

a thm vo ti RNC. Sp xp ng ln c yu cu a thm vo sp xp

ng xung i vi HSDPA.


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3.1.3 Cc trng thi giao thc i vi HSDPA v HSUPA.

Cc trng thi [1],[3] RRC i vi HSDPA v HSUPA l ging so vi trong

Re99. Cell DCH l trng thi m c s dng khi m truyn dn d liu hot

ng v t cc thit b u cui trn DCH. T trng thi cell DCH, u cui c thc dch chuyn ti cell FACH hay trng thi xa hn, cng trc tip t trng thi

cell DCH hay thng qua trng thi cell FACH nu n khng c d liu trong b

m. iu ny xy ra ph thuc vo s iu chnh b nh thi mng sau mt vi

giy. iu ny cn thit l mt cn bng trc vi thi gian p ng mng i

vi truyn dn gi u tin khng i sau chu k khng hot ng v t vo kha

b nh thi. S chuyn tip ly thi gian theo yu cu qu trnh thit lp hay cu

hnh li. Vic gi mt ti nguyn d tr ngi s dng HSDPA/HSUPA khi ykhng c d liu truyn l khng hiu qu t dung lng h thng hay t im

s dng ti nguyn BTS ca view.

D liu c th c pht i trong tnh trng cell FACH, nhng khng ch s dng

knh truy nhp chuyn tip i vi ng xung v knh truy nhp ngu nhin i

vi ng ln, n gii hn tc d liu nh cc knh khng mong mun bt c

cu hnh nng cao no ca HSUPA v HSDPA. Thit b u cui trong trng thi

cell FACH tip tc gii m cc knh FACH v sau kch hot d liu p ngng xung trong RACH. Da trn lng d liu, thit b u cui c th dch

chuyn ti trng thi cell DCH.

3.2 Tham kho.

Chng 4 Nguyn l HSDPA

4.1 Gii thiu

HSDPA gm cc gii php: Thc hin an xen thi gian truyn dn ngn

TTI=2ms, m ho v iu ch thch ng AMC, truyn dn a m, lp vt l tc


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cao L1, yu cu lp t ng lai H-ARQ. Trong gii php HSDPA, thit b sp xp

gi tin s c chuyn t b iu khin mng v tuyn RNC ti Node-B nhm

gip ngi s dng d dng truy nhp vo cc chc nng thng k giao din v

tuyn. K thut sp xp gi tin tin tin s gip iu chnh c tc d liungi s dng sao cho thch hp vi cc iu kin knh v tuyn tc thi.

Hnh 1- Tng quan HSDPA

Trong qu trnh kt ni, thit b ngi s dng (UE) s nh k gi mt ch th

cht lng knh CQI ti Node-B cho bit tc d liu no (bao gm k thut

iu ch v m ho, s lng cc m s dng) m thit b ny c th h tr khi

di cc iu kin v tuyn hin thi. ng thi, UE gi mt bo nhn

(ACK/NACK) ng vi mi gi gip node-B bit c thi im lp li qu trnh

truyn d liu. Cng vi chc nng thng k cht lng knh tng ng cho tng

UE trong mt cell, thit b sp xp gi tin s thc hin sp xp cc gi ca cc UE

mt cch cng bng.

4.2 Thut ng kha vi HSDPA.


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4.3. Cu trc knh HSDPA

T hnh 2 cho thy trong cu trc knh ca HSDPA c thm mt knh vn ti

mi, knh chia s ng xung tc cao (HS-DSCH) mang d liu ngi

dng, knh vt l tng ng c gi l HS-PDSCH.

Hnh 2. Cu trc knh HSDPA

M ngun knh HS-DSCH bao gm mt hay nhiu m knh vi cc thng s

hn hp dn tri ti 16 loi. Ti a 15 m nh vy c th c sp xp trong knh

dnh cho yu cu iu khin v cc sng mang d liu. M ngun tng thch

c chia s trong min thi gian, chng hn, n c sp xp dnh cho mt

ngi s dng ti mt thi im. Cng c th chia s m ngun bng cch thchin phn chia theo m; trong trng hp ny, c th c hai hoc bn ngi s

dng cng chia s m ngun trong mt khong an xen thi gian truyn dn TTI

(S d HS-DSCH cung cp khong thi gian an xen truyn dn ngn TTI=2ms

nhm gim tr thch nghi lin kt, tng thi gian x l sp xp gi...)

Ngoi d liu ngi s dng, Node-B cn thc hin truyn dn bo hiu iu

khin nhm thng bo sp xp cho ngi dng k tip. Bo hiu ny c sp xp

trong knh iu khin chia s tc cao (HS-SCCH), l knh dng chung cho cc

ngi s dng, v n c thc hin bng cch truyn dn hai khe thi gian HS-

SCCH TTI. Knh HS-SCCH c m ho bi mt mt n ngi dng c trng,


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ng thi n cha ng c lp iu khin thng tin mc thp hn, bao gm cc

chc nng iu ch, sp xp m, m ho knh v yu cu lp t ng lai H- ARQ.

Trn mi cu trc knh l lin kt knh vt l dnh ring tc thp (DPCH)

cho c hai hng uplink v downlink. Knh lin kt hng downlink thc hin titn hiu sng mang v tuyn ti bo hiu lp 3 tng t nh nhim v yu cu

iu khin cng sut knh uplink. Thc cht, knh uplink c s dng nh mt

knh phn hi (feedback channel), c chc nng truyn ti cc bo nhn TCP tc

thi. Nu cn thit, mt s dch v khc nh dch v thoi cng c th c ti

trn knh DCCH.

Ngoi ra gii php HSDPA cn cung cp thm knh iu khin vt l dnh

ring (HS-DPCCH) trong hng uplink nhm ti thng tin ch th cht lng knhCQI ging nh i vi cc bo nhn H- ARQ.

4.4 Knh chia s ng xung tc cao(HSDSCH).

HSDSCH l mt knh truyn dn mi mang d liu ngi s dng hin thi vi

HSDPA. Trong lp vt l HSDSCH c nh x trong knh chia s vt l ng

xung tc cao(HSPDSCH). im khc nhau chnh so vi DCH Re99-da trn

cc hot ng ca gi d liu nh sau:

Thiu iu khin cng sut nhanh. S iu chnh kt ni la chn s kt

hp gia cc m thch hp, tc m ha, iu ch c s dng.

Truyn dn vi bc iu ch cao hn DCH. Vi iu ch bin 16QAM,

s lng cc bit c mang i trong iu kin thch hp trn mt tn hiu

bng hai ln so vi QPSK ca Re99.

Vic phn phi ngi s dng da trn s sp xp trong sut 2ms, vi bo

hiu lp vt l nhanh. Khong thi gian truyn dn TTI cng di hn DCH,

cho php cc gi tr nh l 10,20,40,80ms.

S dng truyn dn li lp vt l v kt hp truyn dn li, trong khi vi

DCH, nu s dng truyn dn li, chng da trn truyn li mc RLC.


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Thiu chuyn giao mm. D liu ch c gi i t mt cell HSDSCH

phc v.

Thiu thng tin iu khin lp vt l trn HSPDSCH. iu ny c mang

i thay cho HSSCCH i vi s dng HSDPA v trong DCH lin hp. Hot ng a m vi thnh phn tri rng c nh. Ch c thnh phn tri

rng 16 c s dng trong khi DCH thnh phn tri rng c th l tham s

di ng gia 4 v 512.

Vi HSDPA ch c m ha turbo c s dng,trong khi vi DCH th m

ha chp cng c th c s dng.

Khng c truyn dn gin on(DTX) trn mc khe. HSPDSCH cng

c pht y hay khng pht trong sut thi gian TTI 2ms.

Mt c im quan trng ca HSDSCH l c tnh ng v kh nng chia s ti

nguyn bi chu k phn phi 2ms. Khi chng l cc d liu i vi mt ngi s

dng c phn phi trn HSPDSCH, chng s c gi i lin tc trong sut

2ms TTI. S khng c truyn dn gin on DTX trn mc khe ging nh

DCH,trong khi vic phn phi ti nguyn m ca m ng xung (vi mt

thnh phn tri rng c nh) vi DCH l cch b sung ring vi tc d liu

thp hn. Trong hnh 4.4, v tr ca DTX trong khe lm gim pht sinh nhiu

ng xung nhng gi ta nguyn m b chim theo kh nng tc d liu cao

hn trong DCH. V d i vi 384kbps ng xung, vic d tr ngun m khng

b thay i khi dch chuyn ti mt tc bit thp hn. Do , nu cho php tc

nh l 384kbps, th u thm vo gim xung 16kbps, ch c mt cch gim

lng tiu th ti nguyn l cu hnh li kt ni v tuyn.


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iu ny chim thi gian c trong vic cu hnh li v kha, tc d liu tin timt gi tr mi nh hn cho n khi vic cu hnh li ci khc s thc hin

nng cp tc d liu mt ln na. Vi HSPDSCH, nu khng c d liu

c truyn dn, n s khng truyn dn trn tt c HSDSCH i vi ngi s

dng trong yu cu, nhng ti nguyn i vi 2ms c phn phi ti ngi s

dng khc thay th.

HSPDSCH lun lun c pht trong kt ni vi HSSCCH v thm vo, thit b

u cui cng lun nhn DCH, mang cc dch v ging nh chuyn mch m

thanh AMR hay video nh l SRB.

Nhng ti nguyn m ho HS-DSCH gm c mt hoc nhiu b m nh hng

vi h s phn b c nh SF 16. Phn ln 15 b m ny c th phn b cho

nhng yu cu v truyn dn d liu v iu khin. Cc ti nguyn m ho sn

sng c chia s ch yu trong min thi gian nhng n c th chia s ti nguyn

m ho bng cch dng m ho a thnh phn. Khi c thi gian v b m c

chia s, t hai n bn ngi s dng c th chia s ti nguyn m ho trong cng

mt TTI.


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Hnh 3: Thi gian v b m c chia s trong HS-DSCH

4.4.1 HS-DPCCH:

y l knh ng ln, c s dng mang tn hiu bo nhn (ACK) n Node-B

trn mi khi (block). N cng c dng ch th Cht lng knh CQI

(Channel Quality), l yu t c s dng trong AMC.

Hnh 4 : C cu truyn dn HS-DSCH


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4.4.2 M ha HSDSCH.

Nh gii thiu v HSDSCH, ch c m ha turbo l c s dng i vi

HSDSCH. N c hot ng bi trn thc t th m ha turbo hot ng tt hn

m ha chp khc s ch i i vi tc d liu cc nh. Chui m ha knhc n gin ha t mt DCH tng ng, y khng yu cu thc hin pht ra

nh DTX hay ch nn i vi HSDSCH. y ch c mt hot ng knh

truyn dn ti mt thi im, do , mt vi bc trong ghp knh v gii ghp

knh c yu cu. Bn pht hnh mi thm vo l hot ng ca QAM16 v kt

qu ca vic bin thin s lng bit mang i bi cc knh vt l tr khi s lng

cc m s dng c gi c nh. Mt chc nng khc l s xo trn bit trong lp

vt l i vi HSDSCH.i vi 16QAM, y l mt chc nng k thut ca s sp xp li chm im,

vi nh x cc bit vi cc k hiu khc nhau ph thuc vo s lng truyn dn.

y chnh l mt u im khi m i vi 16QAM, tt c cc k hiu u khng

c kh nng li bng trong chm im. iu ny dn n cc k hiu khc nhau

c s lng ca cc k hiu bn cnh vi v tr k hiu theo trc, vi s lng ln

nht ca k hiu hng xm cng ln th b gii m khng chnh xc so vi cc k

hiu khc trn ng trc.


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Chc nng xo trn trong hnh 4.5 c a ra trnh c trnh t dy khi kt

thc lp cc k hiu ging nhau. iu ny c th xut hin trong mt vi kiu ni

dung, v c bit khi khng s dng s m ha cc lp cao hn. Trong trng

hp m thit b u cui c mt vi im kh khn vi c lng mc cng sut

HSDSCH v do ,l do cho hot ng xo trn lp vt l c a ra. Hot

ng ny ging nhau i vi tt c mi ngi s dng v do n hon ton m

bo tnh cht bo hiu v gii iu ch tt.

Chc nng Hybrid ARQ(HARQ) c ch ra nh l mt block n trong dy m

ha trong hnh 4.5 c th c chia thnh cc phn khc nhau(nh ch ra trong

hnh 4.6). Chc nng HARQ bao gm chc nng nh x tc hai trng thi vi

vic cho php iu chnh d tha ca cc ln truyn li khc nhau khi s dng

truyn li khng ng nht.


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B m ch ra c th l mt b m o, vic thc hin thc t bao gm mt block

nh x tc n. HARQ c th c hot ng trong hai cch khc nhau vi

cc ln truyn li ng nht hay khng ng nht.

Trong trng hp chc nng nh x tc c ng nht gia cc ln truyn dnv lun lun gi cc bit ging nhau sau hot ng nh x tc c gi. Nguyn

l ny c m t trong hnh 4.7. Bt chp s lng ln truyn li, hot ng nh

x tc lun c gi khng i i vi mi ln truyn ca cc gi tng t.

B thu u cui phi lu cc mu thu c nh l cc gi tr mm. iu ny yu

cu b nh hn l b m ch c u ra ca gii m turbo. Khi m b nh nhanh,

chng s gii hn bao nhiu b nh nh th c kh nng c trong mt thit b u

cui. Trn thc t vic truyn dn li c thc hin bi cc trm c s to thnhgii php ton din kh thi t im u cui ca view.Vi vic thc hin truyn

li t RNC, y c qu nhiu tr v s kt hp mm vi tc d liu ln c

th d dng yu cu b nh ln hn.

i vi truyn li khng ng nht hay cn gi l s d gia tng s dng mt nh

x tc khc nhau gia cc ln truyn li. Gii php ny yu cu b nh ln hn

trong b thu v phi c thch ng vi dung lng thit b ngi s dng. Thit

b u cui vi cc tham s ng nht nhng dung lng b nh mm ln hn c

th qun l khc vi s d gia tng tr tc d liu ti a. Chc nng nh x

tc c a dng gia cc ln truyn li khc nhau v trong vic gii m knh

thc hin hin thi c th c thc hin i vi mi ln truyn dn hoc d liu

c th c gi trong cc b m o.


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Nu ln truyn li lp vt l sai hoc vt qu s lng ln truyn li th lp kt

ni v tuyn RLC s thc hin truyn li y . iu ny xy ra vi s chuyn

i cell HSDSCH dch v hoc i khi kh nng bao ph km hay theo li bo

hiu m c th y b m vi d liu khng mong mun. Trng hp him saul do kim tra li trong bo hiu, c cp trong kt ni vi cc chi tit

HSDSCH.

Phn on knh vt l trong hnh 4.5 nh x d liu an xen gia cc knh vt l.

C hai s an xen c ng nht trong Re99 QPSK v trong trng hp

16QAM khi c hai khi an xen c s dng.

4.4.3iu ch HSDSCH.

Trong khi DCH ch s dng iu ch QPSK,HSDSCH c th thm vo s dng

iu ch bc cao hn:16 QAM, trong qu trnh nghin cu tnh kh thi ca

HSDPA c rt nhiu phng n la chn khc nhau v d nh 8PSK hay 16QAM

cng c tho lun nhng cha c a vo h thng ti cc phm vi thch ng

kt ni cho php i vi QPSK v 16QAM v tc lp li/nh thng khc nhau


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i vi m ha turbo. Chm im 16QAM v QPSK c minh ha trong hnh

4.9. Vi nhiu im trong chm im,16 thay th cho 4, tc l c ti 4 bit c th

c mang trn cng mt k hiu thay th cho 2 bit trn mt k hiu vi QPSK.

Nh ch ra trong hnh 4.9, vic s dng iu ch bc cao hn a ra quyt nh b

sung ng bin. Vi 16QAM, n khng c hiu qu hn khng ch c cu

hnh pha u ra chnh xc m nhng yu cu bin cn c d tnh i vi d

on pha ng hn. iu ny gii thch ti sao cht lng tn hiu c yu cu

tt hn khi s dng 16 QAM thay th cho QPSK. Trong ng xung, knh pilot

chung cht lng tt (CPICH) cho php vic d on ca knh ti u m khng

cn qu bit trn u pilot c trng ngi s dng. CPICH a ra thng tin pha

trc tip, nhng y l yu cu d on cng sut khc nhau gia mc cng

sut ca CPICH v HSDSCH d tnh bin thng tin ng nht. iu ny

cho thy pha cui ca trm c s cng c s chuyn i cng sut trong sut

qu trnh truyn dn 2ms.

HSDSCH c th s dng mt s lng b m ghp vi thnh phn tri rng ca

16. S lng ti a l thuyt ca m cho php trong mt cy m vi thnh phn

tri rng l 16, nhng vi cc knh chung v cc knh DCH kt hp cn mt vi

khng gian, s lng thch hp ti a l 15. Khi m mt thit b u cui n c


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th thu ti 15 m trong sut TTI 2ms ph thuc vo kh nng ca thit b u

cui, c m t trong phn 4.5. Trong h thng ny c th c cc lu lng khc

l cc khong m ha tiu th nh l m thanh CS hay cc cuc gi video, m

khng c nh x trong HSDPA. Do qun l ti nguyn v tuyn s quytnh khong m cho php i vi s sp xp trong BTS.

V nguyn l, mt ci c th to ln khong m nhiu hn vi cc m xo trn

ph nhng khi chng khng phi trc giao vi cc m di cc m xo trn chnh,

kt qu l tng dung lng khng vt qu tng. Do , vic s dng ca cc

m xo trn khc c hn ch vi ch nn. HSDSCH tri rng v iu ch

c chi tit hn trong [4].

4.5Knh iu khin chia s tc cao.HSSCCH c hai khe so snh vi HSDSCH nh c ch ra trong hnh 4.10. N

cho php HSSCCH mang thng tin bo hiu thi gian gii hn vi vic cho php

thit b u cui gii iu ch m c ng. Mt thnh phn tri rng ca 128

cho php 40 bit trn mt khe c mang i(vi iu ch QPSK). y khng c

bit iu khin cng sut hay pilot trn HSSCCH v do , pha chun ging nh

i vi HSDSCH. Vi mt phn ca thng tin, ging nh cc m c tri

rng trong HSDSCH, yu cu cho php trc khi bt u s dng HSDSCH,

HSSCCH c phn thnh 2 phn:


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Phn th nht mang thng tin yu cu cho php kh nng gii tri rng

ca cc m ng v cng cha ng thng tin iu ch. iu ny cho php

c truyn dn u cui ch vi 5 hoc 10 m, ngoi tr vic phn phi

khong m trn 15 m. Do vi mt u cui truyn dn mt s lngnh cc m, cc m trong s dng c th c gii m t HSSCCH v yu

cu i vi gii tri rng c gii hn ch i vi cc m kia nhm mc

ch i vi u cui. Vic sp xp ny khng vt qu gii hn nh sn

bi kh nng ca u cui.

Phn th hai cha t thng tin khn v d nh khi qu trnh ARQ c

pht. Mt bo hiu v mt gi truyn dn mi hoc lin quan ti mt gi

c pht sm hn cng c c bao gm trong . Tr trng hp lntruyn trc i vi mt gi khng thu c chnh xc, th bo hiu d liu

mi bo cho u cui l vic truyn dn c c th b xa t b m. iu

ny c ngha l s ph thuc vo thit b, rng c th y l ln truyn dn

li mc RLC(ch bo nhn RLC) hoc n gin d liu b hy b v

u vo c chp nhn mt lng d li(ch khng bo nhn). Thng

tin kiu d tha v chm im cng c mang trong phn 2, nh l kch

thc block truyn dn.

Thi gian gia HSSCCH v HSDSCH cho php thit b u cui c mt khe

thi gian cu hnh ngoi vi cc m gii tri rng v thit lp iu ch. i

vi cc tham s gi li, thi gian x l khe phi c xt n trc khi truyn dn

qua v mt TTI mi 2ms c th bt u.

Khi m HSDPA c hot ng s dng nguyn l ghp knh phn thi,th ch c

duy nht mt HSSCCH c th c cu hnh. Trong trng hp ny ch c mt

ngi s dng thu d liu ti mt thi im. Hnh 4.11 minh ha trng hp ny

vi mt HSSCCH n.

Khi y l mt yu cu c c ghp knh phn m, th s c nhiu hn mt

HSSCCH c yu cu bao gm, nh ch trn hnh 4.12. Mt thit b u cui n

c th xt ti hu ht 4 HSSCCH, bn thn h thng cng c th cu hnh tr


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trng hp nhiu hn. Mt trong nhng hot ng i vi ghp knh phn m l

trng hp khi m c nhiu hn 5 m c th c dnh cho HSDPA s dng. c

bit, khi xt n thit b mt pha d kin, chng c th tr thnh thit b u cui

m c th thu ti a ch 5 hoc l 10 m. Tc d liu cao hn v dung lngu cui thp hn l yu cu i vi ghp knh phn m.

Vic s dng ghp knh phn m l yu cu khng cn thit khi cc b mang c

chia s vi lu lng DCH, hay khi y l mt mong mun c nhng ngi s

dng d liu HSDPA hot ng vi tc d liu cho php-384kbps hoc cao

hn. Nhn chung, tc d liu cho php i vi mi ngi s dng trong cc

trng hp khc nhau s ph thuc vo c vic phn phi cng sut v mi trng

v kiu thit b u cui ang s dng, nh m t cc phn sau.M ha knh ch l mt phn ba m ha chp( vi m ha turbo khng nhn c

i vi lng thng tin nh). Trong phn th 2, y l s kim tra d tha tun

hon(CRC) m bo rng y khng c s sai lch thng tin. Mt tn hiu li

vi mt s lng qu trnh HARQ c th gy ra vn nh n c th lm sai lch


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b m, d , mt 16-bit CRC c s dng m bo an ton hiu qu. i

vi phn th nht, y khng c CRC v kh khn t ra l tch bit c cc

HSSCCH khc nhau vi vic l mi ci nhm vo yu cu ca UE. iu ny c

thc hin bi mt thit b u cui c trng hot ng vi vic cho php d tmHSSCCH phc v cho yu cu ca thit b u cui trong khi vn gi thng tin

thi gian gii hn trong cc khong nh ca mi khe.

4.6 Knh iu khin vt l dnh ring tc cao.

Hot ng ca HSDPA cn thng tin phn hi lp vt l ng ln t thit b u

cui n trm c s cho php cc kt ni thch nghi v truyn dn li lp vt l.

Cc tn hiu c cung cp trong knh m song song,hot ng DCH u ra

khng i, iu ny cho php hot ng trong chuyn giao mm cng nh trong

trng hp khi m tt c cc BTS trong dy hot ng cha nng cp truyn

dn HSDPA. y l mt kh nng khi m cell HSDSCH phc v gi cc knh


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HSSCCH v HSDSCH v tng ng, ch c mt cell HSDSCH phc v yu cu

gii m phn hi ng ln. Vi vic gi s tn ti DPCCH ng ln v

DPDCH khng i,dy hot ng c th ph hp vi Re99 da trn cc trm

gc. Kt qu tr gi cho vic a vo cc knh m song song l t s trung bnhca dng sng tn hiu ng ln(PAR) tng ln, vi kt qu l tng cng sut

truyn dn trong cc trng hp bit thp hn.

Thng tin phn hi ng ln c mang trn HSDPCCH. Phn hi HARQ thng

bo cho trm gc gi c gii m chnh xc hay khng. Thng tin cht lng

knh (CQI),tng ng, bo cho trm gc sp xp tc d liu thit b u cui

ch i c th thu c mt im gi ng thi gian.

HSDPCCH s dng mt thnh phn tri rng ca 256 v c mt cu trc2ms/3khe. Khe u tin c s dng i vi thng tin HARQ. Hai khe cn li

c dng cho CQI. Thng tin HARQ lun lun c gi khi c mt HSSCCH

gii m chnh xc thu trc tip ng xung trong khi tn s truyn dn CQI c

iu khin bi tham s h thng k. i vi tt c cc khe th y l tham s chia s

iu khin vic lp li. Vic lp li qu chu k 2ms ghp c yu cu trong

mt s trng hp, v d hot ng cnh cell, khi m cng sut cho php khng

m bo hiu qu cht lng i vi vic chp nhn phn hi. iu khin cngsut t cell HSDPA khng phc v cng c th gim mc cng sut HSDPCCH

thu trong vng chuyn giao mm khi cc thit b u cui phi gim mc cng

sut truyn dn ng ln nu mt vi cell trong dy hot ng gi mt lnh h

cng sut.


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HSDPCCH ch l mt k hiu t thng hng vi DPCCH/DPDCH. iu ny lin

quan n vic cn thit trnh s sai lch qu ln trong thi gian khi m c thit

b u cui v qu trnh x l nt B c phn ra i vi tt c cc trng hp

yu cu. Thi gian t i c minh ha trong hnh trn 4.14,thi gian

HSSCCH/HSDSCH ng xung s quyt nh lc truyn dn HSDPCCH.

Hot ng HSDPCCH ci tin trong Re6 ci thin hot ng cnh cell. S

ci thin c hiu qu bng vic a vo pre/post-amble i vi knh DPCCH.

Khi m HSSCCH c thu, thit b u cui s gi mt dy cc khong ca bo

hiu ACK/NACK trong khung HSPDCCH 2ms trc, tr khi y l mt gitrong TTI trc. y l nguyn nhn khin cc thit b u cui khng ch pht

thng xuyn hn m cn cho php cc trm thu BTS bit trc l ACK hay l

NACK c pht i. Vi vic trnh pht hin khng truyn dn, thng c

ch nh DTX- ykhng yu cu la chn gia ba gi tr m ch gia ACK v

NACK. Hiu qu ln nht khi y l mt dng lin tc cc gi nhng tr trng

hp ca cc gi tn s l yu cu cng sut nh gim. Cc thnh phn khuch i

thit lp i vi HSDPCCH khng yu cu s dng nh l gi tr cao, v cngsut truyn dn dng cho hot ng ca DPCCH/DPDCH c gim.

Vic m ha HARQ l n gin, trong Re5 y l mt dy ca 1 gi i i vi

ACK v 0 i vi NACK. Trong Re6 cc dy khc nhau c a ti cc pre

amble v post amble nhng ACK/NACK th vn c gi khng i.


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i vi CQI, m ha c a vo, ging vi m ha TFCI, vi vic mang thng

tin CQI t thit b u cui n trm gc. Gi tr CQI m thit b u cui bo co

khng ch tng ng ti 0/cE N hay tn hiu ti t s tp m(SIR) thit b u cui

ang th nghim. Gi tr bo co l mt chc nng ca mi trng a thnh phn,kiu thu u cui, t s nhiu ca trm c s c so snh vi cc ci khc v

cng sut c sn ca BTS HSDPA.

Li ch r rng t vic tip cn ny l mt gii php xc nh s t ng thch ng

vi cc vic thc hin cc b thu c kh nng khc nhau v s bin i mi

trng v do , a n mt bo hiu vi tc d liu tt nht yu cu bi thit

b u cui bao ph vi mi trng trong yu cu. iu ny xa b cc yu cu

t mng cui xt, c tnh tr ca cell/thnh phn trong vn . Ch duy nht

gi tr u vo t mng l gi tr phn phi xc sut HSDSCH thit b u cui c

th c s dng trong mng.

C th vi chuyn i ny th mng c th d dng cn bng vi iu ny khi gi

thit rng trm gc bit trc thit b u cui. Bo co CQI c minh ha trong

hnh 4.15, ch ra rng khi thit b u cui gn trm gc v gi thit phn phi

cng sut HSDSCH cao, mt gi tr CQI cao c thng bo. Tng ng, khi m


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thit b u cui gn ti cnh cell th CQI bo co mc thp hn, nht l khi phn

phi cng sut nt B HSDPA k vng thp. Khi ti hoc gn ti cnh cell, th hu

ht nhiu u n t cc cell khc v do gi tr hnh hc biu din l thp-di

0dB hoc trong mt vi trng hp th gi tr ny m.4.6.1 FDPCH

i vi Re6, vic ti u ha thc hin i vi trng hp khi ch cc gi dch v

hot ng trong ng xung khc hn l SRB. Trong trng hp ny, c bit l

vi tc d liu thp, vic ti u ha b chu nh hng khi m DCH ng

xung a ra qu nhiu bit trn u v cng c th gi thit c qu nhiu on m

nu tm kim mt s lng ln ngi ang s dng dch v tc bit thp nh

VoIP. Gii php l s dng trong cc trng hp nh th ny mt EDPCH,da trn phin bn c tho ri ca DPCH m thc hin iu khin cng sut.

Khi so snh FDPCH vi DPCH Re99,ch c trng iu khin cng sut truyn

dn(TPC) c gi( nh ch ra trong hnh 4.16). Trong , b nh thi gc c

gi li trnh yu cu iu chnh b nh thi trong vic thc hin chu trnh iu

khin cng sut Re99.

Ti nguyn m l thi gian chia s,mt vi ngi s dng c th chia s cc on

m ging nhau i vi thng tin iu khin cng sut. Mi ngi s dng nhn

thy knh m c mt k hiu trn mt khe i vi thng tin iu khin cng sut

truyn dn (TPC) v gi thit khng c s truyn dn trong lc ngh ca cc k

hiu. Vi mt vi ngi s dng, mng cu hnh mi ngi s dng c m tng

t nhng khc v thi gian khung v do , nhng ngi s dng c th c

pht trong ngun m n. Trn 10 ngi s dng c th chia s mt m SF256, do

lm gim vic s dng on m i vi DCH c lin kt i vi nhng

ngi s dng vi tt c cc dch v nh x ti HSDSCH.


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Nguyn l c m t trong hnh 4.17, khi m hai ngi s dng cng chia s

mt on m ging nhau trong hng xung. DCH ng ln khng b tc ng.

Trong trng hp ny, SRB phi nm trn HSDSCH nh khi y khng c ch

i vi cc bit d liu trn FDPCH( khng c DPDCH).

FDPCH c mt vi hn ch khi s dng. Trc tin, n khng cho php cc dch

v yu cu d liu phi c nh x ti DCH, nh l cc cuc gi thoi AMR v

CS video. Hn na, vic thiu cc thng tin iu khin c ngha y l mt

phng php ging phn hi-da trn s phn tp b pht khng th s dng.

Vic s dng s phn tp theo chu trnh ng c da trn iu chnh pha c

trng cho ngi s dng,khi no th cc k hiu iu khin c yu cu i vis kim tra chiu quay pha a vo. Mt khc, khi dng FDPCH, SRB c th li

dng t tc d liu cao ca HSDPA v gim thi gian thit lp dch v.


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Khi m cc SRB c nh x ti HSDSCH s dng FDPCH,cht lng kt ni t

cell HSDSCH phc v l gii hn nht. m bo xp x gii hn pht hin

li kt ni v tuyn, th tnh nng ca thit b u cui i vi vic thit lp cc

lnh iu khin cng sut ng xung trong DPCCH ng ln c thay

i,chnh v th FDPCH c th b pht hin t cell HSDSCH phc v. Do , li

kt ni v tuyn c pht hin trong thit b u cui ch t FDPCH ca cellHSDSCH phc v, m khng phi t DPCCH kt hp mm nh trong Re99.

4.6.2 S iu chnh kt ni HSDSCH.

S iu chnh kt ni l mt hot ng khi n hot ng vi chi tit 2ms vi

HSDSCH. Khi a vo quyt nh sp xp, MAC-hs trong BTS cng s quyt

nh mi 2ms vi b kt hp iu ch v m ha pht. S iu chnh kt ni

c da trn CQI lp vt l ang c phc v bi thit b u cui.

Vic s dng iu chnh kt ni, mng cng s khuch i t gii hn ca hotng iu khin cng sut trong ng xung. Khi cc tn hiu trn ng xung

khng th s dng qu ln mt phm vi hot ng trnh vn gn-xa gia

cc tn hiu t ngun ging nhau, hot ng iu khin cng sut ng xung b

gii hn nhiu hn. Trong khi trn ng ln mt phm vi hot ng 71dB hoc


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ln hn c s dng th trn ng xung ch c th s dng khong 10-

15dB.

S lng chnh xc th ph thuc vo vic thc hin, mi trng knh v cc

thnh phn tri rng a vo. iu ny c ngha l i vi nhng ngi s dnggn trm gc th mc cng sut pht l cao hn mc cn thit i vi kh nng

pht hin tn hiu. S iu chnh kt ni a n mt dung sai chnh xc trong s

dng bng vic la chn tham s truyn dn trong cch l yu cu nng lng k

hiu tng ng chnh xc hn vi cng sut k hiu cho php. iu ny c

minh ha trong hnh 4.18, y iu chnh kt ni nh l mt chc nng t s

sng mang/nhiu c minh ha.Bn thn iu chnh kt ni da trn thng tin

CQI v n cng khin nhng kha cnh khc thnh nhng account bn cnh chiudi tn hiu hay C/I.


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Bng vic chuyn i t QPSK thnh16QAM, y c khc mt vi dB, ph

thuc vo mi trng, vic thc hin tc m ha v s lng m khin

phm vi hot ng tng cng c th t n 30dB.

Dung dng thit b u cui tc ng n bo co nh tt c thit b, c bit l

trong pha trc, s khng h tr cn thit iu ch 16QAM hay nhiu hn 5 m

song song. Khi vt qu phm vi tc d liu m thit b u cui c th truyn

dn, n s ch bo co mt lch hn l im iu ch/m ha cao nht m n

c th chp nhn. Bng CQI c nhiu hoc t i s kt hp cch qung u ca

qu trnh iu ch, s lng cc m, kch thc block truyn dn hay m ha.

Bng v d CQI n gin trong hnh 4.19 trnh by cc kh nng u cui khc

nhau. Bng pha bn phi hnh 4.19 l dnh cho cc loi u cui 11,12(Ch

QPSK) v do , sau 5 m ch c mt lch tc d liu 1.8Mbps i vitrng thi c bo hiu. Tng ng, bng CQI i vi loi 7(7.2Mbps) thc hin

trn tt c cc cch ti 10 m trc khi s dng lch nh ca n. i vi tt

c cc loi khc, lch c s dng sau mt vi im, tr trng hp loi 10

vi tt c cc cch ti 14.4Mbps v kt qu khng yu cu lch trn nh.


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Tham s c li lin TTI trong dung lng u cui khng c mt mt tc ng ti

bng CQI s dng, ch c s lng m v iu ch m ha l to ra s khc

nhau. Ngoi tr l lp 14.4Mbps ti ch c mt im khc l kch thc block

truyn dn ti a c chp nhn khi so snh vi mt dung lng ca u cui10Mbps. Gi tr CQI tng ng vi trng hp khi 14.4Mbps c th c thu m

khng c k vng xut hin vi tn s cao trong mng thc.

4.6.2.1 Gii thiu hot ng lp vt l HSDPA

Hot ng lp vt l HSDPA i qua tt c cc bc di y i khi mt hoc

nhiu ngi s dng c cu hnh nh ang s dng HSDSCH v d liu bt

u t n b m nt B.

S sp xp nt B c tnh-trn tng 2ms mt- i vi mi ngi s dngvi d liu trong b m: tnh trng knh, trng thi b m, thi gian i

vi ln truyn dn cui cng, tr hon pht li v vv. Tiu chun chnh xc

trong sp xp l vic cp php thc hin cung cp c trng hon ton t

nhin v khng phi l mt phn trong cc c tnh k thut ca 3GPP.

Cc tham s iu khin tnh nng sp xp c trng ha v c ni r

hn trong phn sau.

Ch c mt thit b u cui c quyt nh nh b cung cp trong mt

TTI ring l,nt B s nhn bit cc tham s HSDSCH cn thit, bao gm

s lng m, kh nng s dng 16QAM v gii hn dung lng u cui.

Nt B s bt u pht i HSSCCH hai khe trc TTI HSDSCH tng

ng. Vic la chn HSSCCH l t do( t mt dy ca 4 knh) gi thit l

y khng c d liu i vi thit b u cui trong khung HSDSCH trc.

Thit b u cui qun l dy u cui c trng ca c 4 HSSCCH cho

bi mng. Ch c mt u cui c gii m phn 1 t mt HSSCCH dnh

cho thit b u cui , n s bt u gii m phn cn li ca

HSSCCH v s a vo b m cc m cn thit t HSDSCH.


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Sau khi gii m cc tham s HSDSCH t phn 2, thit b u cui c th

quyt nh d liu thuc qu trnh ARQ no v chng c cn c kt hp

vi d liu c sn trong b m mm hay khng.

Trong phin bn Re6, mt pre-amble c gi trong trng ACK/NACKnu c tnh c cu hnh s dng bi mng(v nu nh khng c gi

no trong TTI trc). Vic gi i ca pre-amble da trn gii m

HSDSCH ch khng phi bn thn HSDSCH.

Nh gii m kh nng kt hp d liu, thit b u cui gi trn hng

ng ln bo hiu ACK/NACK, ph thuc vo u ra ca CRC c dn

trn d liu HSDSCH.

Nu mng tip tc pht i d liu i vi cc u cui ging nhau trongcc TTI lin tip, th thit b u cui s nm trn HSSCCH tng t m

c s dng trong sut TTI trc.

Trong Re6, khi m dng d liu kt thc, thit b u cui gi mt post

amble trong mt trng ACK/NACK, gi thit cc c tnh c khi

ng.

Hot ng HSDPA ng b trong iu kin thit b u cui chp nhn mt gi

c pht i trn ng xung. Mng bn cnh, tuy nhin ng b trong iu kin

khi mt gi hay mt ln truyn dn li i vi ln truyn dn sm hn c gi i.

iu ny cho php s t do cn thit i vi vic thc hin sp xp v c cho

php bi thng tin qu trnh ARQ trn HSSCCH.

Thi gian hot ng ca thit b u cui gia cc s vic c c trng ha

chnh xc t b thu HSDSCH, cho php bi gii m HSDSCH v kt thc vi

truyn dn ACK/NACK ng ln. Nh ch ra trong hnh 4.20, c mt khe thi

gian phn ng 7.5 t u cui ca TTI HSDSCH ti bt u ca truyn dn

ACK/NACK trong HSDPCCH trn ng ln.


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Gi tr ca cc khe 7.5 l chnh xc, ch c mt vi bin thin l do s hiu chnh

k hiu gia HSDPCCH ng ln v DPCCH/DPDCH ng ln, do gi tr

thi gian nm trong ca s chip 256.

Trong Re6, vi pre v post-amble trong vic s dng b nh thi l khng thay

i nhng i vi gi u tin ca khe ACK/NACK trc c s dng i vi

pre-amble nh ch ra trong hnh 4.21. Tng ng, khi m truyn dn kt thc,


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post-amble c pht i trong tnh trng khi m mt ACK/NACK c th xut

hin.

4.6.2.2 Tnh di ng

Khi so snh vi DCH th im khc nhau ln nht trong thc hin di ng l thiuchuyn giao mm i vi HSDSCH. Trong khi y ch l mt cell HSDSCH phc

v, th bn thn DCH c lin kt c th l trong chuyn giao mm v duy tr

dy hot ng nh trong Re99. Yu cu i vi thit b u cui l cho php

ph ln vi 6cell trong dy hot ng DCH. Khi m hot ng trong chuyn giao

mm vi vic s dng HSDPA, y c mt yu cu iu chnh cc trng

hp o thu c thng tin v nhng chuyn i trong di t i ca cc cell

trong dy hot ng.

Nhng thng tin ny khng kch hot cc hot ng trong DCH nhng c th kchhot s chuyn i trong cell HSDSCH phc v vi hot ng HSDPA. cho

php cc thng tin ny c kh nng i vi RNC, trng hp o 1D c iu

chnh cho php trng hp- da trn bo co khi m di t i ca cc cell

trong dy hot ng thay i, hoc chnh xc hn khi cell vi di CPICH ti u


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trong nhng thay i dy hot ng. Khi m nhng ch tiu bo co y , th

thit b u cui s gi- nh l mt phn ca bo hiu iu khin ti nguyn v

tuyn- mt bo co o ti RNC.

Trong bn Re5,cell HSDSCH phc v ch c th c chuyn i bn trong dyhot ng ca thit b u cui bng vic s dng mt bin php cu hnh li knh

vt l. Theo , khi m thit b u cui pht hin ra rng mt cell bn cnh c

y tiu chun cho vic a thm cell ti dy hot ng, th u tin, cell yu

cu c a vo dy hot ng trc khi hot ng HSDSCH phc v c th

b chuyn i ti cell khc. Trong Re6, tnh trng ny b chuyn i, chnh v

th, bin php update dy hot ng cng c th thc hin bn ngoi s chuyn

i cell HSDSCH phc v.Khi mt chuyn i ca cell HSDSCH din ra, thit b u cui s xa sch tt c

cc b m ti thi gian chuyn giao v dch chuyn theo trm gc mi nh c

cu trc trong bo hiu RRC ng xung. Tng ng, ti thi im ,chuyn

giao s chim nt B cng nh xa cc gi vn nm trong b m ca n, bao gm

cc qu trnh HARQ cha kt thc mt cch hp l. Mng s phi phn loi cc

gi khng gi(khi s dng ch bo nhn RLC). Trong ch bo khng nhn,

cc gi khng c pht i, nu nh c mt vi gi trong s chng b mt trongqu trnh hot ng chuyn i cell, nhng cc gi b mt c th l nh nht bng

vic tnh ton cn thn RNC khi chuyn giao s thc hin v khng gi- thi

im trc - cc gi ti cell HSDSCH phc v ang c thay th.Trong sut

qu trnh ng b chuyn i cell HSDSCH phc v, mt vi s ngt qung

truyn dn gi c th nh nht khi cc thnh phn thit b u cui v mng bit

chnh xc khi no chuyn giao thc hin. ti thiu d liu b mt ti mc c

th, vic truyn dn ca n v d liu ph ti c ch bn ngoi dy (PDU) phi

c a ra trong ch bo khng nhn RLC trong Re6, cho php mng truy

nhp v tuyn trn mt t UMTS(UTRAN) s dng 2 casting trong sut

chuyn i cell HSDSCH phc v, vi vic m bo rng cc gi c kh nng b

mt ngun ca nt B c th t c ch nt B.


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HSDSCH da trn vic s dng ch nn i vi thit b u cui lin h thng

v tnh ton lin tn s. Mc d bn thn HSDSCH khng th thc hin ch

nn, vic truyn dn d liu hin thi v iu khin bo hiu u b treo(nh ch ra

trn hnh 4.24) khi y l mt khong trng trn ng xung m ph ln bt k

phn no ca truyn dn HSSCCH hay HSDSCH. Trong trng hp ny th thit

b u cui s b qua ton b truyn dn. Tng ng, bo hiu ng ln s

khng thc hin khi y l mt s sp xp lng lo trn ng ln. Khi c thng


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tin kiu ch nn v s sp xp nm trong nt B, y l mt kh nng kt hp

thng tin. Mt phng n khc l s dng truyn dn DCH i vi d liu

trong khi vn c hot ng ca ch nn. Khi cc tham s chnh xc, ch nn

khng c k vng c s dng trong bt k trng hp no gn vi trmgc, nhng li thc hin khi kh nng bao ph vWCDMA l km hoc khi lp cell

HSDPA v d trong lp micro cell, cn thit chuyn i khi vo khu vc bao

ph ca macro cell. S chuyn i i vi h thng truyn thng di ng ton cu

gy ra mt st gim tc d liu ngi s dng, s khc nhau hin ti ph thuc

vo dung lng mng GSM.

Tc d liu cho php v mt l thuyt ln n 384kbps ph thuc vo y ch

c mt dch v c s c cho php hay tc d liu ci tin i vi gii php

ton cu cng c chp nhn. Tnh trng knh v s lng khe c chp nhn

trong thit b u cui a m gii hn tc d liu thc hnh t khong 200 n

300kbps.

i vi chuyn giao t cc mng GSM n cc mng GSM, cc c tnh k thut

Re6 bao gm c vic chp nhn i vi chuyn giao gi. iu ny cho php gim

thi gian ngt qung chuyn giao ging vi mc t c trong Re99 da

trn chuyn giao cuc gi thoi, khi m u cui ngi s dng trong mt mng

tham s ha thc s khng pht hin chuyn i ca h thng. Trong Re5, y l


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mt mng tn ti chuyn i cell khi chuyn thnh GSM tng tc x l

trong khi trong Re99 da trn cc mng ch la chn li cell t vWCDMA c

cho php ti GSM.

4.7 Tnh ton BTS cho s hot ng ca HSDPA y c 3 php tnh ton mi c xc lp trong bn pht hnh5 m m c

cng nhn l lm gim mc thng tin cn thit v t chc ca HSDPA trong

RNC.i vi lp vt l th tnh ton nh sau:

Cng sut m khng phi l ca HSDPA ci lm c s lm r cng sut c s

dng cho tt c knh khc hn l HSDPA(HSDSCH v HSSCCH).Trong phin

bn pht hnh th 6 ny,php o ny s tnh ph ln tt c knh ng xung m

khng s dng cho mc ch HSDPA hay HSUPA. y khng c im notrong php o cng sut thc t HSDPA v cng khng khc gia cng sut

khng phi HSDPA v cng sut truyn dn ti a BTS,hay v tr cng sut

HSDPA s c cung cp bi RNC.

y ch l mt tin trnh, l phn m lp MAC c bao ph khi m HSDSCH

cung cp php o tc bt. Php o ny cng em li thng tin trong vic tnh

trung bnh tc d liu trn lp u tin qua chu k o.

Hn na, mt php trong Iub[8] c nh ngha l cng sut yu cu i viHSDSCH. Ci ny s a ra nhng thng tin v cng sut c lng trn lp u

tin yu cu t c gi tr tc bit m bo.Nt B c th lit k ra danh

sch thit b u cui m yu cu cng sut rt cao t c tc bt m bo

cho kt ni.

4.8 Tnh nng u cui

Da vo cu hnh ca HSDPA th bn thn cc thit b u cui l mang

tnh ngu nhin. Khi da vo hot ng ca HSDPA, cc thit b u cui s ch

ra khong 12 hng mc k thut khc nhau. Ph thuc vo cc hng mc c

cung cp,tc d liu ng xung ti a tnh ton l nm gia 0.9-14.4Mbps.

Dung lng HSDPA l c lp vi dung lng ca bn pht hnh c s 99, nhng

nu nh HSDSCH c cu hnh cho cc thit b u cui,th dung lng DCH


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ng xung b gii hn ti gi tr ca thit b u cui. Mt thit b u cui c

th c dung lng DCH l t 32,64,128,384kbps. Ni chung, kh nng bnh

thng thit b u cui c th t n 384

4.8.1 L1 v s lng RNC a vo.

Tc d liu lp vt l c xc nh da theo cc tham s sau:

S lng m s dng

iu ch

Tc m ha hiu dng.


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V d v tc bt i vi s kt hp tham s khc nhau m khng c s lin

quan i vi nh dng truyn dn khc nhau v s kt hp ngun (TFRC) c

ch ra trong bng 4.4

S BTS c th cp pht tc d liu i vi ngi s dng ring l t

c s kt hp tc bt cao lin tc hay a ngi s dng khi m tc d liu

trung bnh ngi s dng c phn chia theo s lng ngi s dng cng chia

s ngun. Do m tc d liu cnh cell thng hn ch nhiu so vi cc v

tr trm gc.

Khi m chng ta xt n nhng u RLC/MAC v c nh kch thc PDU

l320bit, sau chng ta ly tc d liu lp RLC i vi tng u cui khcnhau trong bng 4.5.i vi cc yu cu c mc khc nhau l gim i 5% theo

giao thc IP.

4.8.2 Tham s Iub.


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Hot ng ca HSDPA cn s lng ln tham s m phi c cn gia

cc thit b u cui v nt B. N c cung cp t node B ti RNC nh ch ra

trong hnh 4.25 da trn mt thut ton cung cp c bit v bo hiu dung lng

u cui bng mt thit b ti RNC s dng tn hiu RRC trong sut qu trnh thitlp b ni.

Cc tham s c th c phn chia thnh cc loi nh sau:

Tham s i vi vic cp pht ngun nt B ch dn.

Tham s k hoch.

Tham s u cui c trng.

Node B cn c nhn bit dung lng u cui. iu ny c ngha l cn xt

n thut ng s lng m cung cp v s iu ch nh in p gia cc gii hn

TTI. l s cn thit khi m s dng hn 4 m HS_SCCH, sau cc u cui

khc nhau c th iu khin cc cm HS_SCCH khc nhau tng phn mt.

Vic iu khin theo lch trnh c th cho php qun l cht lng dch v(QoS)

nodeB theo s .Mi s ch dn u im khc nhau li c th c dng i

vi ngi s dng hay l i vi dch v. V d,dch v IP c u im lp biu

qu trnh cao hn l dch v d liu kiu s liu c bn bt chp nhng dch v

ny l dng cho nhng ngi s dng ging nhau hay khc nhau. Hn na k

hoch qun l cc b m c th c iu khin bi thi gian hy b vi vic ch

ra nhng gi thi gian ti a c th b gi li trong b m v thi gian ht hiu

lc, s lng b loi b.


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Cc tham s u cui c trng tr thnh mt phn giao din Iur ging nh y l

s cn thit chy HSDPA thng qua Iur.

4.9T chc lp MAC ca HSDPA

Trong HSDPA, vic sp xp cc gi tin c thc hin ti lp truy nhptrung bnh, MAC-hs. Chc nng iu khin truy nhp trung bnh MAC-hs c

t ti Node-B, ti y cc quyt nh sp xp gi tin s c thit lp tc thi.

Mt khc, an xen thi gian TTI l 2ms. Mt chng trnh sp xp gi tin in

hnh tn l Round-Robin trong chng trnh sp xp thi gian ni ngi s dng

c phc v tun t s ngh tt c u nhn c thi gian cp pht trung bnh

nh nhau.

Tuy nhin, t l sp xp cao kt hp vi dy cc iu ch v m ho thch ng

AMC li thch hp vi gii php HSDPA. Mt phng php sp xp gi tin ph

bin l chng trnh sp xp gi cn i. Vi chng trnh sp xp ny, yu cu

phc v c xc nh bi cht lng knh ln cn tc thi cao nht. Chng hn,

chng trnh sp xp s c gng d theo fading nhanh ca knh v tuyn. Khi qu

trnh la chn da trn cc iu kin lin quan, ngi s dng vn nhn c mt

thi gian nh v xp x bng nhau, tuy nhin kh nng h thng c th d dngnng ln mc 50%..


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Nh vy, vi nhng u im v k thut, gii php HSDPA do Nortel

Network xut c mt lot cc cng ty hng u v truyn thng nh

Nokia, LG, SAMSUNG, Ericsson, Alcatel ng dng cho cc sn phm ca


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mnh. Trong tng lai khng xa, HSDPA s l s la chn hng u cho

WCDMA.

4.10 Tham kho.

Chng 5: Nguyn l HSUPA

5.1 HSUPA vi DCH phin bn 99.

Cc cng tc k thut vi HSUPA c tin hnh sau thnh cng phin bn

u tin ca truy cp gi ng xung tc cao HSDPA ca 3GPP phin bn 5

vo gia nm 2002.HSDPA c nng cao dung lng ng xung nhng

dung lng ng ln khng ph hp vi ng xung HSDPA. Do , cng

vic ci thin ng ln bt u c thc hin bi 3GPP.R rng l phi la

chn kho st k thut s dng i vi HSDPA v nu ph hp th chp nhn

vi ng ln xem c tng thch khng.

HSUPA khng phi l mt tnh nng chun,nhng s dng hu ht nhng c

im c bn ca vWCDMA phin bn 99 lm vic. Vic la chn cell v ng

b ha,truy nhp ngu nhin u cn thit v c gi khng i vi hot ng

ca HSUPA.Ch c mt s thay i duy nht l cch cp pht d liu ngi s


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dng t thit b ngi s dng ti node B,cn li tt c nhng chi tit k thut

khc c gi khng thay i.

V d nhng chc nng iu khin chu trnh cng sut trong phin bn 99 l bn

cht i vi hot ng ca HSUPA. HSUPA cung cp mt cch linh hot cao hn

vi tc ng ln l 384kbps c th c xem l ti a c th thc hin i vi

vWCDMA trc HSUPA. Mt k thut tng t i vi HSDPA ang c s

dng bng vic gii thiu b ghp li ARQ(HARQ) vi tc ng ln rt cao.

Node B s da trn s ng ln (nh ch ra trn hnh 5.1) v d dng

truyn dn a m hn so vi phin bn 99.

5.2 Thut ng chnh vi HSUPA.

5.2.1 Gii thiu

Tnh nng chnh HSUPA ca h thng vWCDMA 3GPP trn thc t l knh

truyn dn ng ln mi EDCH-mang mt vi c im tng t i vi ng

ln nh HSDPA vi knh truyn dn mi_ knh chia s ng xung tc cao

(HS DSCH) cung cp cho ng xung. Knh truyn dn E_DCH cung cp c

nh node B da trn s n. lp vt l c nh HARQ vi s d gia tng v c ly

thi gian truyn dn ngn hn 2ms.Mc d vy, khng ging nh HSDPA,

HSUPA khng phi l knh chia s, nhng l mt knh dnh ring, bng cu trc


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E-DCH l ging vi DCH ca phin bn 99 nhng vi lch trnh nhanh hn v

HARQ hn l ng ln HSDPA,vi mi UE c mt knh dnh ring E_DCH,

phn d liu ti nt B s c tip tc v c lp vi DCH v E_DCH ca cc UE

khc. Bng 5.1 lit k ra cc yu cu i vi DCH,HSDPA,HSUPA.

Tng ng, nhng knh bo hiu mi c yu cu (nh ch ra trong hnh 5.2), tt

c cc knh (loi tr knh qung b) c ch ra trong hnh u cn thit i

vi hot ng HSUPA. Trong hnh 5.2, gi s rng ng xung l trn DCH

trong tt c cc trng hp d tnh rng HSDPA u c th c s dng nhng

r rng ch ng xung DCH c ch ra trong vic a thm vo knh lin

kt HSUPA.

Nhng knh iu khin k hoch E_DCH chp nhn knh c lp E_AGCH vE_DCH chp nhn knh tng i E_RGCH tt nh cung cp truyn dn li trn

E_DCH HARQ knh bo hiu(E_HICH) c cp n trong ton b phn tip

theo.D liu ngi s dng c mang trn knh d liu vt l dnh ring ci

tin(E_DPDCH) trong khi thng tin iu khin mi li nm trn E_DPCH,s

c ni n phn sau.Theo DCH phin bn 99 th knh iu khin vt l dnh

ring (DPCCH) khng c g thay i v yu cu i vi DPDCH ph thuc vo

kh nng dch v ng xung nh x ti DCH.

Khng ging nh HSDPA, HSUPA khng c cung cp b iu ch thch ng

bi v n khng cung cp biu iu ch cao hn. iu ny cng dn n l

trong thc t c rt nhiu biu iu ch phc yu cu nng lng trn bit ln


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hn c truyn dn hn l vic truyn dn n gin thng vi nhng knh

a m song song s dng iu ch BPSK .

ng xung theo phm vi hot ng ca cng sut knh pht s nh i, y

l trng hp khi m tn hiu ng xung c pht i vi nng lng nhiu hnmc cn thit c th c c cht lng tt.

Do vic s dng iu ch bc cao hn c th cung cp tc d liu cao hn

m khng cn yu cu cao hn vi cng sut pht i vi HSDPA. Vi tnh trng

ng ln khc v tc d liu cao yu cu tt c cng sut pht ca UE

thm ch gn bng node cng c cho php vi iu ch v truyn dn a m.

5.2.2 C nh L1 HARQ cho HSUPA

Giao thc yu cu lp t ng hn hp HARQ l dng giao thc ti truyn dn,

c ng dng ci thin tnh cht chng chu cc li tng thch lin kt. Node

B c th yu cu ti truyn dn cc gi d liu nhn b li, ng thi gi cho

mi gi mt bo nhn (ACK) hoc hi m bo nhn cc gi d liu khng nguyn

vn (NACK) ti UE. Hn na, Node B c th thc hin phi hp mm (softcombine), chng hn phi hp cc qu trnh ti truyn dn vi qu trnh truyn dn

gc trong b thu d liu. Trong Node B thc hin gi lp cc gi ging nhau,

ngoi ra Node B cn thc hin m ha bng cch gi i cc bit chn l (parity

bits).


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Giao thc HARQ trong HSUPA thuc dng giao thc Dng li v i (Stop and

Wait) gia Node B v UE. iu ny lm gim thi gian tr ti truyn dn xung

mc thp nht so vi RLC ti RNC trong cc h thng Rel99. Kt qu ca vickhi to t l li truyn dn trong lp vt l c th thit lp mc tng i: t 10

ti 20 %. Gim tr truyn dn s ci thin c thng lng. Tuy nhin vn c

mt s khc bit trong giao thc HARQ ca HSUPA v HSDPA. HARQ trong

HSUPA da trn qu trnh ti truyn dn ng b ti ng ln. Khng tn ti

gii hn m ha ti nguyn ng ln ging nh ng xung. Biu sau y

cho chng ta thy qu trnh x l HARQ

Hnh 2. Qu trnh x l HARQ

Nguyn l c bn cho HARQ i vi HSUPA cng tng t nh i vi

HSDPA. Sau mi TTI pht i node B bo hiu ti UE pht ni m cc gi s

c nhn ng hay khng. Trong trng hp pha thu nhn khng ng th UE

s pht li gi. Nt B s c gng khi phc li gi bng vic kt hp nng

lng truyn li vi truyn trc cho n khi gi y c thu ng hoc gi tr

truyn li l ti a.Vi HSUPA, HARQ c th s dng s kt hp Chase ni m

mi mt ln pht li l mt bn sao chp chnh xc ca vic truyn ban u hoc

gia tng s d khi pht li bao gm s bt d a vo i vi s bit pht ban u.


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im khc nhau chnh gia HARQ HSUPA v HARQ HSDPA l HSUPA HARQ

l tnh ng b y v vi s d gia tng tr n bn s d c pht c th

c xc nh trc, n cng hot ng trong chuyn giao mm.

5.2.3 Sp xp vi HSUPATrong phin bn 5, HSDPA thay i s sp xp ng xung t RNC ti node

B to ra quyt nh sp xp vi thi gian ch l ti thiu gn vi giao din v

tuyn c th. S vi HSUPA c nhng im ging i vi ng ln v thay

i s sp xp vi nt B nhng s tng t gia s sp xp ca HSDPA v

HSUPA l cui. Vi HSDPA, tt c ngun cung cp cell c th c a trc

tip ti ngi s dng ring l trn tng chu k thi gian ngn, v bng cch ny

c th t n tc gi d liu rt cao i vi mi UE ring bit, nhng li tngthch u ra vi tt c cc ci khc vi tc d liu bng 0.Trong khong thi

gian tip theo khi m ngun node B c dng cung cp mt vi UE khc vn

vn. Hin nhin l vi HSUPA th khng th, bi v HSDPA l mt ti nhiu kiu

sp xp cn HSUPA l s sp xp t nhiu ci ti mt ci. Ngun cng sut

truyn dn ng ln ca mt cell c phn b ti tng ngi s dng, thc

hin mt cch n gin, mi UE c mt b pht ca chnh n v ch c th pht i

d liu t UE ring bit . Chnh v th, hin nhin, trong ng ln th nguncng sut truyn dn ng ln ca cell khng ch c a n tng UE n l

ti mt thi im v ti cc UE khc mt vi thi im khc, nhng ngi s

dng phi c ngun cng sut pht ca ring h v chc chn l khng th chia

s. iu ny cho thy s cn thit phi c mc cao hn ca s sp xp ng

ln song song, v do , vic tip cn knh dnh ring c nhn thy c tnh

kh thi i vi HSUPA, ngc li vi vic tip cn knh chia s HSDPA.

Khi nghin cu nhng ci trn, cn nhc v sp xp HSUPA c th qun lch biu

HSDPA, v thay th, suy ngh v sp xp DCH nhanh nht. Ngun chia s ca

ng ln l nhiu ng ln tng ln hay tng cng sut thu thy trong u thu

node B. Mi UE, tr khi pht vi cng sut y , u khng th dng m ch

thc hin mnh ngun , nhng y li l ch li rt ln bit c s lng


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ngun mi mt thi im m mi UE dng c gng gi nguyn mc

nh hng ca nhiu ti mc ti a.

Nu nh chng ta gi s rng tt c cc UE hot ng nu nh mun pht i ti tt

c cc thi im vi tc d liu cao nht c th, sau b lp lch biu s lm

vic vi ng ln. Mt cng vic n gin nhn vo mt ngi s dng miv trong khi phi thu nh vic phn phi(cp pht) i vi ngi s dng c.

Do n rt l khc so vi lch biu ca HSDPA, nhng trn thc t vn cn rt

nhiu h thng phin bn 99 ang hot ng. Khi cha sn sng cho php i vi

RNC lp lch biu hot ng da theo yu cu ca UE v chuyn i pht,

n gin n ch d phng tt c nhng ngi s dng vi tc d liu ti a c

nh v chng c cho php s dng khi no h c th. Nu nh s s dng

ti a l thp hn hoc vic thc hin khng tn ti, nu nh ti ng ln tng

ln qu cao, hoc nhng ngi s dng mi b a vo cell, sau vic cp pht

b thp hn.

Hnh 5.3 cng ch ra biu ti ng ln nhng mi lin kt cell a n cng

sut nhiu ng ln nh c ch ra. Pha trn im c nh, cell tr ln khng


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bn khi th nghim tt c ngi s dng sinh ra nhiu qu ln t nhng ngi s

dng khc v do yu cu tng cng sut truyn dn c nghe v bt u to

ra nhiu ln hn ti cell nh hng ngc tr li nhng ngi s dng khc vn

vn. iu ny cng c bit n nh l hiu ng ring phn khi m ti u cuin khng phi l vn bn ni to nh th no, bn vn khng th c nghe.

Hin nhin, tnh trng ny khng tng thch cao trong h thng WCDMA v

cng vic chnh ca vic lp lch biu ng ln l chc chn rng s qu ti l

khng xy ra. Th hai, quan trng i vi u cui ngi s dng l phi c gng

v s dng dung lng ng ln c th m khng cn phi lo nguy c v s qu

ti trong cell.

S sp xp HSUPA tin gn hn vi giao din v tuyn,s c nhiu thng tin tcthi v tnh trng nhiu ng ln v c th iu khin tc d liu ng ln

trong phng thc nhanh.

5.3 Knh vt l v knh truyn dn E_DCH

Hnh 5- Tng quan cc knh HSUPA

5.3.1 Gii thiu

Trong HSUPA, knh dnh ring tng cng E-DCH c gii thiu nh mt

knh vn ti mi c chc nng truyn ti d liu ngi dng trn ng ln. Ti

lp vt l, n c bin dch thnh hai knh ng ln mi sau y:


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- Knh d liu vt l dnh ring E-DCH (E-DPDCH), v

- Knh iu khin vt l dnh ring E-DCH (E-DPCCH).

Knh E-DPCCH mang thng tin iu khin lin kt vi E-DPDCH. Trn ng

xung, 3 knh mi gii thiu sau y c chc nng iu khin:

- E-AGCH : Knh cp pht tuyt i E-DCH mang cc tn hiu cp pht tuyt i.

- E-RGCH : Knh cp pht tng i E-DCH mang cc tn hiu cp pht tngi.

- E-HICH: Knh ch th HARQ mang cc tn hiu ACK/NACK.

Knh E-AGCH ch c truyn i t cell phc v. E-RGCH v E-HICH c

truyn i t cc tuyn lin kt v tuyn chnh l mt phn ca qu trnh thit lp

tuyn lin kt v tuyn phc v v t cc tuyn lin kt v tuyn phi phc v.

Cn ghi nh rng cc knh HSUPA c sp xp ti trn cng ca cc knh dnh

ring ng ln/ng xung, do mi UE c thm mt knh vt l dnh ring

ng ln v ng xung (DPCH). Ti ng ln, mt phn knh dnh ring

(Factional Dedicated Channel F-DPCH) c th ty chn s dng. Knh F-DPCH

c gii thiu trong n bn R.6 ca 3GPP nhm ti u qu trnh ng dng m

ha knh ng xung. Theo , mt s UE c th chia s cng mt m knh

ng xung vi thng s dn SF 256. t c iu ny, knh F-DPCH s

dng mt cu trc khe mi ch cha cc bit iu khin cng sut truyn dn TPC

m khng cha cc trng tiu hay trng d liu nh cu trc khe DPCH

ng xung thng thng. Bng cch gn cho mi UE mt khong b thi gian


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(Timing offset), c th cho php ghp ti a 10 UE trn mt m knh dnh cho F-

DPCH.

5.3.2 Qu trnh x l ca knh truyn dn E_DCH

Thc hin knh truyn dn l mt chc nng chuyn i s cp pht cc blocktruyn dn bi lp MAC ti cc bit c pht i trong knh vt l.Hnh 5.4 ch ra

tng quan v DCH v thc hin EDCH t lp MAC ti knh vt l.

Mt dy qu trnh thc hin knh truyn dn EDCH lun lun chim mt block

thc hin truyn dn trong mt TTI, bi v i vi DCH, mt nhm cc block

truyn dn i vi mi cu hnh DCH s c cp pht ti dy thc hin. Hnh 5.5

l s khc nhau gia cc thnh phn trong dy qu trnh thc hin knh truyn

dn i vi EDCH v DCH c minh ha: Phn km theo CRC di vi EDCH lun chim 24 bit CRC truyn cc

block thu t lp MAC. So snh,chiu di CRC i vi DCH c cu hnh

c th l 0,8,12,16 hay 24 bit.


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Cc on m block i vi EDCH chia u vo n thnh cc m block

kch thc bng nhau chnh v th chiu di ca cc block khng vt qu5114bit. i vi DCH, block u tin s ghp ni cc block truyn dn

thnh mt block d liu n trc khi chia.


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M ha knh i vi EDCH lun l m ha tuabin vi tc m ca 1/3.

M ha knh DCH c th cng nhn chp cc m vi tc m hoc 1/3

hoc m tuabin vi tc m ca 1/3.

S phi hp tc v chc nng HARQ lp vt l i vi EDCH phi hpcc bt u ra cc m knh ti bit knh vt l cho php v gii thiu phin

bn d tha khc nhau cn thit cho HARQ gia tng d tha.

S chia on knh vt l i vi EDCH cp pht cc bit knh gia cc

EDPDCH nu nhiu hn mt EDPDCH c yu cu. Chc nng ny cng

tng t trong cc block cng tnh trong dy quy trnh x l DCH.

S nh x ca knh vt l v s an xen i vi EDCH, ging nh i vi

DCH, s xen k cc bt trong khung v tuyn v biu cc bit ctruyn ti v tr xc nh trn knh vt l.

5.3.3 Knh d liu vt l dnh ring.

EDPDCH l knh vt l ng ln mi s dng cho vic pht i cc bit, l

kt qu ca qu trnh x l knh truyn dn EDCH, t thit b di ng n trm c

s. y l mt knh mi tn ti song song vi tt c knh dnh ring ng ln

ca 3GPP phin bn 5(DPDCH v DPCCH dng i vi pht d liu ng ln v

HSDPCCH s dng i vi truyn tin phn hi HSDPA). Vi vic gii thiu v

HSUPA y c 5 iu khc ca vic pht song song cc knh dnh ring ng

ln.

EDPCH c cu trc tng t vi DPDCH ca phin bn 99 vi mt vi b thu

nhn. Chng cng truyn dn vung gc cc nhn t bin i (OVSF) hiu

chnh s lng cc bt knh ti s lng ca d liu c pht i ng thi.Chng

cng s dng iu ch BPSK v cho php mch iu khin cng sut nhanh tng

t nhau.

c im cn ch nht ca EDPDCH chnh l EDPDCH truyn dn mc HARQ

lp vt l nhanh v nt B nhanh da trn lch biu. Tuy nhin, y khng phi l

nhng tnh cht ca dy qu trnh x l v vic lp lch biu l nhn thy trong lp

MAC.


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im khc nhau ln nht i vi EDPDCH l truyn dn cc thnh phn tri

di(SF) l 2 vi vic cho php phn pht 2 ln vi nhiu bit knh trn m hn l s

nhn t tri di nh nht l 4 m DPDCH truyn dn.Tuy nhin, y khng phi

l tt c s tht khi DPDCH c th truyn dn ti 6m SF4 song song khiEDPDCH truyn dn ng thi vic pht i ca 2m SF2 v 2 m SF4v dn n

tc bit lp vt l ti a l 5.76Mbps.

Tc d liu cho tng bc truyn dn l khc nhau. C DPDCH v

EDPDCH truyn dn cc nhn t tri rng 256,128,64,32,16,8 v 4 v tc

bit ca knh vt l tng ng l 15.20.60.120.240.480 v 960kbps vi s

truyn dn m n OVSF.

Nu nh tc bit knh l 960kbps da trn s tri rng thnh phn4 th s

khng hiu qu i vi vic truyn dn i tt c cc d liu t b x l knh

truyn dn,sau tt c chng s c chuyn i s dng hai m SF4 song

song v t c tc bit knh vt l l 1920kbps.Mi th ch khc so vi 2

kiu knh d liu dnh ring im ny. Sau hai m song song SF4, DPDCH

s thc hin cc bc i vi m song song 3,4,5,6,cho n khi tc bit t

c l 5.76Mbps.EDPDCH c mt vi bc v s dng 2 thnh phn trirng.Sau hai m SF4,EDPDCH s thc hin trc tip vi hai m SF2. Nhng

bc ny c ch ra trong bng 5.2.Vic s dng hai m SF2 cung cp mt

vi dy thng qua vic s dng ba hay bn m song song SF4 i vi t s


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cng sut pht cao nht trn trung bnh v cho php thc hin b khuych i

cng sut nhiu u im i vi truyn dn UE tc cao.

im khc bit ch ln nht lp vt l gia hai knh d liu l chiu di 2

ms TTI truyn dn bi EDPDCH. iu ny t c bng vic gi nguyn cutrc khung v tuyn 10ms lun ph hp vi DPDCH, nhng vi TTI 2ms s

dng khung v tuyn 10ms c phn chia thnh5 khung con nh c lp.

im khc nhau gia DPDCH v EDPDCH c lit k trong bng 5.3.Bng

5.4 ch ra tc d liu knh vt l i vi cc thnh phn tri rng khc nhau

i vi c DPDCH v EDPDCH.


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Khi mt TTI 10ms c s dng cho tt c 15 khe ca khung v tuyn

EDPDCH dng phn phi block truyn dn x l bi dy x l knh truyn

dn EDCH.Trong trng hp TTI 2ms,mi khung con 2ms truyn mt block

truyn dn EDCH. Hnh 5.6 minh ha cu trc khung EDPDCH.

EDPDCH khng phi l mt knh c lp nhng yu cu truyn dn ng thi

ca DPCCH.Bt iu khin DPCCH c yu cu cho vic xc nh knh v

bo hiu nhm mc ch xc nh t s nhiu(SIR) b thu v vic phn

chia bit iu khin cng sut bi DPCCH c yu cu i vi iu khin

cng sut ng xung. Khi a ti ci ny th cc knh iu khin c yu

cu song song vi EDPDCH phn phi thng tin b thu bit nhng ci

nh dng ca b pht EDPDCH ti b thu. Knh iu khin mi ny c tn l

EDPCCH,EDPDCH khng th tn ti nu khng c s truyn dn ng b

EDPCCH.

5.3.4 Knh iu khin vt l dnh ring.

EDPCCH l knh vt l ng ln mi s dng i vi vic pht thng tin

ngoi bng v truyn dn EDPDCH t thit b di ng ti trm gc. EDPCCH

cng ging nh EDPDCH l mt knh mi m tn ti song song vi tt cknh dnh ring ng ln ca 3GPP phin bn5, v lun lun truyn dn

ng thi vi EDPDCH.


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m rng EDPCCH lm tng t nh i vi EDPDCH khi m DPCCH

thc hin i vi truyn dn DPDCH, l knh iu khin s phn phi

thng tin cn thit gii m truyn dn knh d liu tng ng. im khc

nhau chnh gia 2 ci l khi a vo thng tin v DPDCH th DPCCH cng

cung cp thng tin chung lin quan n,v d, s c lng knh v iu khin

cng sut,trong khi EDPDCH ch bao gm thng tin v EDPDCH.

EDPDCH ch c duy nht mt nh dng khe(c ch ra trong bng 5.5) vivic s dng 256 thnh phn tri rng v cha dung lng ca 30 bit knh

phn phi trong mt khung con 2ms.N c thit k truyn 10bit thng tin

cho mi mt EDPDCH TTI pht.EDPCCH s dng kiu m ho Reed Muller

bc hai dng truyn dn b ch bo kt hp nh dng(TFCI) m ha trong

DPCCH. iu ny c ngha l kt qu cc bit thng tin c trong 30 bit c

pht i trong knh vt l.S lng cc bit c th c mang i bi EDPCCH

2ms. Nu nh chiu di TTI ca EDPDCH l 10ms th khung con EDPCCH 30

bit s c lp li 5 ln thoe ch mc cng sut bo hiu. Vi vic gii thiu

cu trc khung EDPCCH tng t c th s dng bt chp TTI dng cho

truyn dn EDPDCH. Cu trc khung ca EDPCCH c minh ho trong hnh

5.7 v s m ho v s nh x ca bit EDPCCH c m t chi tit trong [3].

10bit thng tin trong EDPCCH bao gm 3 on khc nhau:

ETFCI. EDCH truyn dn nh dng b bo hiu kt hp gm 7 bit bo

hiu, nh dng truyn dn c pht i ng b trong EDPDCH. V

bn cht, ETFCI ni cho b thu kch thc ca block truyn dn m ha

trong EDPDCH.T nhng thng tin ny m b thu c th bit c bao

nhiu EDPDCH c pht i song song v nhng thnh phn tri rng

no c s dng.


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RSN. Vic truyn li dy 2 bit thng tin s lng dy HARQ ca block

truyn dn ang c gi i trn EDPDCH. Vic truyn dn ban u

ca mt block truyn c gi i vi RSN=0,u tin RSN=1,th 2 thRSN=2 v tt c ln truyn dn tip theo th RSN=3.

Happy bit: suy ra t tn_l mt bit duy nht.N cho bit tc d liu

hin ti m UE c( hay lin quan n cng sut cho php c s dng

i vi EDPDCH.) hoc n c th s dng s phn b cng sut cao

hay khng.

5.3.5 Knh bo hiu EDCH HARQ

EHICH l knh vt l ng xung mi s dng i vi vic pht thun v

bo hiu ngc i vi truyn dn gi ng ln. Nu nt B thu c

EDPDCH TTI pht mt cch chnh xc th n s phn hi li bo hiu

dng(ACK) v n thu TTI khng chnh xc th n s phn hi li vi

thng tin bo hiu m(NACK).

Thng tin EHICH c iu ch BPSK vi kha tt/m v s iu ch ph

thuc vo cell ang pht EHICH. Nu nh EHICH ang n t dy kt ni

v tuyn cha trong kt ni v tuyn EDCH cung cp(pht t trm gc m

c cell EDCH phc v), th c ACK v NACK u c pht i. EHICH

pht bi nt B m khng cha cell EDCH th ch pht i ACK. Nu vi

mt cell m khng thu EDPDCH TTI chnh xc th n s khng lm g. UE

s tip tc pht li cho n khi cell phn hi li vi mt ACK.


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Mc ch ca s phi hp ny l lu li s truyn dn ng xung. Gi

thit rng pha sau cc phng php iu ch khc nhau l cc nt B m

khng c cell EDCH cung cp l nhng ci khng c kt ni tt nht ti

UE v thng khng nhn ng EDPDCH TTI v c phn ln tn hiu lNACK hn l ACK c pht i. Trong cch ny ch c duy nht ACK l

s dng dung lng ng truyn xung. Nh i vi dy kt ni v tuyn

EDCH cung cp,gi thit l tn hiu ACK nhiu hn tn hiu NACK pht

i. Khi c ACK v NACK dn n truyn dn bit BPSK (+1 v -1,b thu

cn phn chia t +1 n -1 v c th l trng hp nu n cn phn chia

t +1 n 0( khi khng truyn).ACK/NACK s c nh x ti truyn dn

EHICH t rt nhiu loi cell khc nhau c lit k trong bng 5.6

Tt c cc cell trong nt B tng t cng c gi thit ti ng truyn

EDPDCH ng ln b thu trong b kt hp v kt qu l tr trng hp l


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nhiu cell trong nt B tham gia vo chuyn giao mm th b thu TTI thnh

cng hoc tht bi ch mt ln m khng tch ri tt c cc cell.

Cu trc knh ca EHICH v ERGCH l ging nhau,v chng c minh

ha trong hnh 5.8. Mi mt bit thng tin li c chia thnh 3 khe. Trongtrng hp m TTI 10ms th 3 khe ny s c lp li 4 ln kt qu trong

bn tin c chiu di 8ms.Vic thu nhn ERGCH pht i t nhng cell

khng ph thuc vo s cung cp dy kt ni v tuyn EDCH. Knh

lun lun-bt chp ERGCH TTI-pht i bn tin di 10ms.

Block xy dng c s ca EHICH/ERGCH l mt dy thng gc c chiu

di 40 bit vi vic cho php a truyn trc tip 40 bit trn cng mt khe

trong mt thnh phn tri rng n 128 knh m.Bit EHICH/ERGCH clp li 3 ln thng qua 3 khe,nhng li s dng cc bo hiu khc nhau

trong mi mt khe theo kiu di chuyn m tt nh.iu ny chnh l

nguyn nhn m cc cp tn hiu khc nhau c s kh ghp trong mi

trng v tuyn thc v kt qu hiu qu c tnh trung bnh theo cch

ny. Dy tn hiu v kiu kh ghp c xc nh trong phn [2].

Mi cell c th s dng nhng m vt qua gii hn 40 tn hiu vi

vic lin kt EHICH v ERGCH mc ch mi UE pha c pht i vi

mt m knh tng ng. Hnh 5.9 minh ha hot ng ca nt B cho vic

kt hp 40 tn hiu trong mt m knh ng xung n.

5.3.6 Knh ph cp t i EDCH.

ERGCH l mt knh vt l ng xung mi s dng i vi vic pht i

tng bc n ln/xung cc s lnh m hiu qu cng sut truyn dn

t i UE cho php dng i vi truyn dn knh d liu (EDPDCH),rt

ra hiu qu trong vic iu chnh ln xung i vi tc d liu ng

ln.


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Chnh xc ging nh i vi EHICH,thng tin ERGCH c iu ch

BPSK vi kha tt/m v s cho php truyn dn ph thuc vo cell c

pht i ERGCH.Cc cell ny li thuc vo dy kt ni v tuyn EDCH cung cp ca mt

UE bng vic xc nh ni dung ERGCH tng ng pht v do cho

php UE kt hp mm vi cc knh.Cc cell ny khng thuc vo dy kt

ni v tuyn cung cp EDCH c th ch pht gim(cch khc l khng

truyn) v do ch c cc cell cung cp v cc cell khc li thuc v dy

kt ni v tuyn EDCH tng t c th tng cng sut truyn dn t i ti

a ca knh d liu c UE cho php.

Mt im khc nhau gia ERGCH v EHICH l s kt hp mm. Tt c

EHICH pht i bi dy lin kt v tuyn tng ng(cc kt ni v tuyn t

node B tng ng va cha lnh iu khin cng sut tng ng) phi mang

ni dung tng ng v l kt hp mm. ERGCH c pht i t dy kt

ni v tuyn EDCH cung cp phi mang ni dung tng ng v l kt hp

mm. Mc ch ca dy lin kt v tuyn EDCH cung cp l nn khm

ph ra mng,s t do khuch i kt hp mm i vi ERGCH pht t

node B v node B cng c kt ni v tuyn EDCH cung cp,hoc c duy

nht mt ERGCH UE c bit t cell EDCH cung cp v s dng ERGCH

i vi tt c UE khc.


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Vi nhng dn chng trn th cu trc khung v ngun tn hiu ca

ERGCH ging i vi EHICH(Hnh 5.8 v hnh 5.9).S khc nhau l trong cc

lp cao hn,mng thng bo UE bi cc ngha ca tn hiu RRC trong x l

tn hiu vi m knh l EHICH v y l tn hiu i vi m knh l ERGCH.5.3.7 Knh cp pht tuyt i EDCH.

EAGCH l knh vt l ng xung mi s dng i vi vic pht i gi

tr tuyt i ca quyt nh sp xp nt B m theo UE bit cng sut truyn t

i,n cng c ph

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