Tim Hieu Cong Nghe 3g

8/14/2019 Tim Hieu Cong Nghe 3g

1/23

TNG QUAN V H THNG THNG TIN DI NG TH H BA

1. M uS pht trin nhanh chng ca dch v s liu m IP t ra cc yu mi i vi

cng ngh vin thng di ng. Thng tin di ng th h 2 mc d s dng cng ngh snhng l h thng bng hp v c xy dng trn c ch chuyn mch knh nn khngth p ng c dch v mi ny. 3G (third-generation)cng ngh truyn thng th hth ba l giai on mi nht trong s tin ha ca ngnh vin thng di ng. Nu 1G (thefirst gerneration)ca in thoi di ng l nhng thit b analog, ch c kh nng truynthoi. 2G (the second generation) ca TD gm c hai cng nng truyn thoi v dliu gii hn da trn k thut s. Trong bi cnh ITU a ra n tiu chun hah thng thng tin di ng th h th 3 vi tn gi IMT 2000. IMT 2000 m rngng k kh nng cung cp dch v v cho php s dng nhiu phng tin thng tin.Mc ch ca IMT 2000 l a ra nhiu kh nng mi nhng cng ng thi m bos pht trin lin tc ca h thng thng tin di ng th h th hai (2G) vo nhng nm

2000. 3G mang li cho ngi dng cc dch v gi tr gia tng cao cp, gip chng tathc hin truyn thng thoi v d liu (nh e-mail v tin nhn dng vn bn), downloadm thanh v hnh nh vi bng tn cao. Cc ng dng 3G thng dng gm hi ngh videodi ng; chp v gi nh k thut s nh in thoi my nh; gi v nhn e-mail v filenh km dung lng ln; ti tp tin video v MP3; thay cho modem kt ni n mytnh xch tay hay PDA v nhn tin dng ch vi cht lng cao

2. Th no l cng ngh 3G3G l thut ng dng ch cc h thng thng tin di ng th h th 3 (Third

Generation). c rt nhiu ngi nhm ln mt cch v hoc hu gia hai khi

nim 3G v UMTS (Universal Mobile Telecommunications Systems). hiu th no l cng ngh 3G, chng ta hy xt qua i nt v lch s pht trin cacc h thng in thoi di ng. Mc d cc h thng thng tin di ng th nghim utin c s dng vo nhng nm 1930-1940 trong trong cc s cnh st Hoa K nhngcc h thng in thoi di ng thng mi thc s ch ra i vo khong cui nhngnm 1970 u nhng nm 1980. Cc h thng in thoi th h u s dng cng nghtng t v ngi ta gi cc h thng in thoi k trn l cc h thng 1G.

Khi s lng cc thu bao trong mng tng ln, ngi ta thy cn phi c binphp nng cao dung lng ca mng, cht lng cc cuc m thoi cng nh cung cp

thm mt s dch v b sung cho mng. gii quyt vn ny ngi ta ngh nvic s ho cc h thng in thoi di ng, v iu ny dn ti s ra i ca cc hthng in thoi di ng th h 2.

chu u, vo nm 1982 t chc cc nh cung cp dch v vin thng chu u(CEPT Confrence Europene de Postes et Telcommunications) thng nht thnhlp mt nhm nghin cu c bit gi l Groupe Spciale Mobile (GSM) c nhim vxy dng b cc ch tiu k thut cho mng in thoi di ng ton chu u hot ng di tn 900 MHz. Nhm nghin cu xem xt nhiu gii php khc nhau v cui cng


2/23

i n thng nht s dng k thut a truy nhp phn chia theo m bng hp (NarrowBand TDMA). Nm 1988 phin bn d tho u tin ca GSM c hon thnh v hthng GSM u tin c trin khai vo khong nm 1991. K t khi ra i, cc h thngthng tin di ng GSM pht trin vi mt tc ht sc nhanh chng, c mt 140quc gia v c s thu bao ln ti gn 1 t. Lc ny thut ng GSM c mt ngha mi l h thng thng tin di ng ton cu (Global System Mobile).

Cng trong thi gian k trn, M cc h thng in thoi tng t th h th nhtAMPS c pht trin thnh cc h thng in thoi di ng s th h 2 tun th tiuchun ca hip hi vin thng M IS-136. Khi cng ngh CDMA (Code DivisionMultiple Access IS-95) ra i, cc nh cung cp dch v in thoi di ng M cungcp dch v mode song song, cho php thu bao c th truy cp vo c hai mng IS-136v IS-95.

Do nhn thc r v tm quan trng ca cc h thng thng tin di ng m Chuu, ngay khi qu trnh tiu chun ho GSM cha kt thc ngi ta tin hnh d nnghin cu RACE 1043 vi mc ch chnh l xc nh cc dch v v cng ngh cho h

thng thng tin di ng th h th 3 cho nm 2000. H thng 3G ca chu u c gi lUMTS. Nhng ngi thc hin d n mong mun rng h thng UMTS trong tng lais c pht trin t cc h thng GSM hin ti. Ngoi ra ngi ta cn c mt mongmun rt ln l h thng UMTS s c kh nng kt hp nhiu mng khc nhau nh PMR,MSS, WLAN thnh mt mng thng nht c kh nng h tr cc dch v s liu tc cao v quan trng hn y s l mt mng hng dch v.

Song song vi chu u, Lin minh Vin thng Quc t (ITU InternationalTelecommunications Union) cng thnh lp mt nhm nghin cu nghin cu vcc h thng thng tin di ng th h 3, nhm nghin cu TG8/1. Nhm nghin cu t

tn cho h thng thng tin di ng th h th 3 ca mnh l H thng Thng tin Di ngMt t Tng lai (FPLMTS Future Public Land Mobile Telecommunications System).Sau ny, nhm nghin cu i tn h thng thng tin di ng ca mnh thnh H thngThng tin Di ng Ton cu cho nm 2000 (IMT-2000 International MobileTelecommunications for the year 2000). ng nhin l cc nh pht trin UMTS (chuu) mong mun ITU chp nhn h thng chp nhn ton b nhng xut ca mnh vs dng h thng UMTS lm c s cho h thng IMT-2000. Tuy nhin vn khng

phi n gin nh vy, c ti 16 xut cho h thng thng tin di ng IMT-2000(bao gm 10 xut cho cc h thng mt t v 6 xut cho cc h thng v tinh).

3. Cc tiu ch chung xy dng IMT 2000 nh sau:

IMT-2000 cung cp h tng k thut cho cc dch v gia tng v cc ng dng trnmt chun duy nht cho mng thng tin di ng.

- S dng di tn quy nh quc t 2GHz nh sau: ung ln: 1885 2025 MHz;ng xung: 2110 -2200 MHz. IMT-2000 h tr tc ng truyn cao hn: tc ti thiu l 2Mbps cho ngi dng vn phng hoc i b; 348Kbps khi di chuyn trn xe.Trong khi , h thng vin thng 2G ch c tc t 9,6Kbps ti 28,8Kbps.


3/23

- L h thng thng tin di ng ton cu cho cc loi hnh thng tin v tuyn:+ Tch hp cc mng thng tin hu tuyn v v tuyn+ Tng tc cho mi loi dch v vin thng t c nh, di ng, thoi, d liu,

Internet n cc dch v a phng tin

- C th h tr cc dch v nh:+ Cc phng tin ti nh o trn c s mng thng minh, di ng cc nhn v

chuyn mng ton cu+ m bo chuyn mng quc t cho php ngi dng c th di chuyn n bt k

quc gia no cng c th s dng mt s in thoi duy nht.+ m bo cc dch v a phng tin ng thi cho ting, s liu chuyn mch

knh v s liu chuyn mch gi.- D dng h tr cc dch v mi xut hin.Mi trng hot ng ca IMT 2000 c chia thnh 4 vng vi tc bit R

nh sau:+ Vng 1: Trong nh, pico, Rb 2 Mbit/s+ Vng 2: thnh ph, macr, Rb 384 kbit/s+ Vng 2: ngoi , macr, Rb 144 kbit/s+ Vng 4: ton cu, Rb = 9,6 kbit/s.

IMT-2000 c nhng c im chnh:

3.1 Tnh linh hot:

Vi s lng ln cc v sp nhp v hp nht trong ngnh cng nghip in thoidi ng v kh nng a dch v ra th trng ngoi nc, nh khai thc khng mun

phi h tr giao din v cng ngh khc. iu ny chc chn s cn tr s pht trin ca3G trn ton th gii. IMT-2000 h tr vn ny, bng cch cung cp h thng c tnhlinh hot cao, c kh nng h tr hng lot cc dch v v ng dng cao cp. IMT-2000hp nht 5 k thut (IMT-DS, IMT-MC, TMT-TC, IMT-SC, IMT-FT) v giao tip sngda trn ba cng ngh truy cp khc nhau (FDMA - a truy cp phn chia theo tn s,TDMA - a truy cp phn chia theo thi gian v CDMA - a truy cp phn chia theom). Dch v gia tng trn ton th gii v pht trin ng dng trn tiu chun duy nhtvi 5 k thut v 3 cng ngh.


4/23

3.2. Tnh kinh t:S hp nht gia cc ngnh cng nghip 3G l bc quan trng quyt nh gia

tng s lng ngi dng v cc nh khai thc. .3.3. Tnh tng thch:Cc dch v trn IMT-2000 c kh nng tng thch vi cc h thng hin c.

Chng hn, mng 2G chun GSM s tip tc tn ti mt thi gian na v kh nng tngthch vi cc h thng ny phi c m bo hiu qu v lin mch qua cc bcchuyn.

3.4. Thit k theo modul:

Chin lc ca IMT-2000 l phi c kh nng m rng d dng pht trin slng ngi dng, vng ph sng, dch v mi vi khon u t ban u thp nht.

Phn loi cc dch v ca IMT-2000

Kiu Phn loi Dch v chi tit

Dch v ding

Dch v di ng - Di ng u cui/di ng c nhn/di ng dch v

Dch v thng tinnh v - Theo di di ng/theo di di ng thng minh

Dch vvin thng

Dch v m thanh - Dch v m thanh cht lng cao(16 64 kbit/s)- Dch v m thanh AM (32 64 kbit/s)- Dch v truyn thanh FM (64 384kbit/s)

Dch v s liu - Dch v s liu tc trung bnh (64 144 kbit/s)- Dch v s liu tc tng i cao (144 2 Mbit/s)- Dch v s liu tc cao ( 2Mbit/s)

Dch v a phngtin

- Dch v Video (384kbit/s)- Dch v hnh chuyn ng (384kbit/s - 2Mbit/s)- Dch v hnh chuyn ng thi gian thc ( 2Mbit/s)

Dch vInternet

Dch v Internet ngin - Dch v truy nhp Web (384kbit/s - 2Mbit/s)

Dch v Internet thigian thc

- Dch v Internet (384kbit/s - 2Mbit/s)

Dch v internet aphng tin

- Dch v Website a phng tin thi gian thc (2Mbit/s)

4. L trnh pht trin t cc h thng th h hai n th h 34.1. Lch trnh nghin cu pht trin h thng thng tin di ng th h ba.

Cng trnh nghin cu ca cc nc Chu u cho W-CDMA bt u t cc n CDMT (Code Division Multiple Testbed): Phng th nghim a truy nhp theo m) vFRAMES (Future Radio Multiple Access Scheme: S a truy nhp v tuyn tnglai) t u thp nin 90. Cc d n ny cng tin hnh thc nghim cc h thng W-CDMA nh gi cht lng ng truyn. Cng tc tiu chun ho chi tit c thchin 3GPP. Lch trnh trin khai W-CDMA c cho hnh v.


5/23

Lch trnh nghin cu v a mng W-CDMA vo khai thc

Chu u v Chu , h thng W-CDMA c a ra khai thc vo u nm2002

Lch trnh nghin cu pht trin ca cdma2000/3GPP2 chia thnh 2 pha:

- Pha 1: (1997 1999)

+ Nghin cu pht trin mu u tin ca h thng;

+ Nm 1997: Xy dng tiu chun , xy dng cu trc mu u tin h thng vthit k cc phng tin th nghim chung.

+Nm 1998: Tip tc xy dng mu th u tin ca h thng v cc phng tinth nghim chung;

+ Nm 1999: Kim tra kt ni cho m hnh u tin ca h thng.

- Pha 2: (2000 -2002)

+ Pht trin h thng vi mc tiu thng mi cc nh sn xut hng u ;

+ Nm 2002: Bt u dch v thng mi

4.2. L trnh pht trin t h thng IS-95 th h hai n cdma 2000 th h ba

Mc d mng cdma One (IS-95) khng phi l cc mng u tin cung cp truynhp s liu, nhng y l cc mng c thit k duy nht truyn s liu . Trc htchng x l truyn dn s liu v ting theo cch rt ging nhau. kh nng truyn dn tc thay i c sn trong cdmaOne cho php quyt nh lng thng tin cn pht, v thcho php ch s dng tim nng mng theo nhu cu. V cc h thng cdmaOne s dngtruyn ting ng gi trn ng trc (cc ng truyn dn t BTS n MSC), nn khnng truyn s liu gi c sn trong thit b. Cng ngh truyn dn s liu gi ca

cdmaOne s dng ngn xp giao thc s liu gi s t ong (CDPD: Cellular DigitalPacket Data) ph hp vi TCP/IP.

B sung truyn s liu vo mng cdma2000 s cho php nh khai thc mng tiptc s dng cc phng tin truyn dn, cc phng tin v tuyn, c s h tng v ccthit bi u cui hin c bng cch nng cp phn mm cho chc nng tng tc. Nngcp ln IS-95B cho php tng tc knh cung cp tc s liu 64 115 kbit/s v ngthi ci thin chuyn giao mm v chuyn giao cng gia cc tn s. Cc nh sn xut cng b cc kh nng s liu gi, s liu knh v fax s trn cc thit b cdmaOne ca h.


6/23

Mt trong cc mc tiu quan trng ca ITU IMT 2000 l to ra cc tiu chunkhuyn khch s dng mt bng tn trn ton cu nhm thc y mc cao vic nhiungi thit k v h tr cc dch v cao. IMT 2000 s s dng cc u cui b ti kchc nh, m rng nhiu phng tin khai thc v trin khai cu trc m cho php a racc cng ngh mi. Ngoi ra cc h thng 3G ha hn em li cc dch v ting v tuync cc mc cht lng hu tuyn ng thi vi tc v dung lng cn thit h tr

a phng tin v cc ng dng tc cao. Cc dch v trn c s nh v, o hng, htr cp bo v cc dch v tin tin khc cng s c h tr.

S pht trin ca h thng 3G s m cnh ca cho mch vng thu bao v tuyni vi PSTN v truy nhp mng s liu cng cng, ng thi m bo iu kin tin lihn cc ng dng v cc tim nng mng. N cng s m bo chuyn mng ton cu, ding dch v, ID trn c s vng, tnh cc v truy nhp th mc ton cu. Thm ch cth hy vng cng ngh 3G cho php kt ni mng v tinh mt cch lin tc.

Mt trong cc yu cu k thut ca cdma2000l tng thch vi h thng ccdmaOne v: Cc dch v ting, cc b m ho ting, cc cu trc bo hiu v kh nng

bo mt.Bng cch chuyn t cng ngh giao din v tuyn IS-95CDMA hin nay sang IS-

2000 1X ca tiu chun cdma2000, cc nh khai thc t c tng dung lng v tuyngp i v c kh nng x l s liu gi n 144 kbit/s.

Cng s ra i ca cdma2000 giai on mt, cc dch v s liu cng s c cithin. Giai on 2 cng s uc hnh thnh c cu MAC (Medium Access Control: iukhin truy nhp mi trng) v nh ngha giao thc on ni v tuyn (RLP: Radio LinkPrtcol) cho s liu gi h tr cc tc s liu gi t nht l 144kbit/s.

Thc hin giai on 2 ca cdma2000s mang li rt nhiu cc kh nng mi v cctng cng dch v. Giai on 2 s h tr tt c cc kch c knh (6X, 9X v 12X) c cucho cc dch v ting, b m ho ting cho cdma2000, bao gm ting trn nn IP. Vigiai on 2 cc dch v a phng tin thc s s c cung cp v s mang li c hithun li b sung cho cc nh khai thc. Cc dch v a phng tin s c th thc hinc thng qua MAC s liu gi, h tr y cho s liu gi, h tr y cho dch vs liu gi n 2Mb/s, RLP h tr tt c cc tc s liu n 2Mb/s v m hnh gi a

phng tin tin tin.

L trnh pht trin t cdmaOne n cdma 2000


7/23

C cdma2000 giai on 1 v 2 u c th ho trn vi cdmaOne s dng hiuqu nht ph tn tu theo nhu cu ca khch hng. Chng hn mt nh khai thc c nhucu ln v dch v s liu tc c th chn trin khai kt hp giao on 1 cdma2000 vcdmaOne vi s dng nhiu knh hn cho cdmaOne. mt th trmg khc, ngi sdng c th cha cn nhanh chng s dng cc dch v tc s liu cao th nhiu knhhn s c dnh cho cc dch v ca cdmaOne. V cc kh nng ca cdma2000 giai

on hai sn sng nn nh khai thc khc c nhiu cch la chn hn trong vic sdng ph tn h tr cc dch v mi

4.3. Tng kt qu trnh pht trin ca h thng thng tin di ng n th h ba

Trong qua trnh ny ta tng kt nn tng cng ngh chnh ca thng tin di ng tth h mt n th h ba v qu trnh pht trin ca cc nn tng ny n nn tng ca thh ba. tin ti th h ba c th th h hai phi tri qua mt giai on trung gian, giaion ny gi l th h 2,5.

Tng kt qu trnh pht trin ca cc nn tng thng tin di ng th h 1 n th h 3

5. Cc tiu chun cng ngh ca h thng thng tin di ng th h ba:Cc h thng thng tin di ng th hai gm: GSM, IS 136, IS 95 CDMA v

PDC. Trong qa trnh thit k cc h thng thng tin di ng th h ba, cc h thng thh hai c cc c quan tiu chun ho ca tng vng xem xt a ra cc xuttng thch. Khuyn ngh ITU-R M.1457 a ra 6 tiu chun cng ngh cho giao dintruy nhp v tuyn ca thnh phn mt t ca cc h thng IMT-2000 (tn gi mng 3Gca ITU), bao gm:

- IMT-2000 CDMA Direct Spread (tri ph trc tip), thng c bit di tnWCDMA.- IMT-2000 CDMA Multi-Carrier (nhiu sng mang), y l phin bn 3G ca h

thng IS-95 (hin nay gi l cdmaOne)- IMT-2000 CDMA TDD- IMT-2000 TDMA Single-Carrier (mt sng mang), cc h thng thuc nhm ny

c pht trin t cc h thng GSM hin c ln GSM 2+ (c gi l EDGE).- IMT-2000 FDMA/TDMA (thi gian tn s), y l h thng cc thit b ko di

thu bao s chu u.


8/23

- IMT-2000 OFDMA TDD WMAN (thng c bit di tn WiMAX di ng).

Mi tiu chun trong su tiu chun cng ngh nu trn u c cc cng ty lnv mt s quc gia c nn cng nghip in t, vin thng pht trin ng h v ra sc vnng. Cc tiu chun ny cnh tranh gay gt vi nhau trong vic chim lnh th trngthng tin di ng. Trong ch c 3 cng ngh c bit n nhiu nht v pht trinthnh cng l WCDMA, CDMA 2000 1x EV-DO v WiMAX di ng.

5.1. IMT-2000 CDMA Direct Spread:Cng ngh IMT-2000 CDMA Direct Spread c bit n nhiu hn di tn gi

thng mi l WCDMA, c chun ho bi 3GPP. Da trn cng gh WCDMA hinc hai loi h thng l FOMA (do NTT DoCoMo trin khai Nht) v UMTS (ctrin khai u tin Chu u, sau pht trin ra ton th gii). UMTS l s pht trinln 3G ca h cng ngh GSM (GSM, GPRS & EDGE), l cng ngh duy nht c ccnc chu u cng nhn cho mng 3G. GSM v UMTS cng l dng cng ngh chimth phn ln nht trn th trng thng tin di ng ngy nay (chim ti 85,4% theo GSA8-2007).

Mt s c im ch yu ca cng ngh WCDMA bao gm: Mi knh v tuyn c rng 5 MHz; tng thch ngc vi GSM; chip rate 3,84 Mbps; h tr hot ngkhng ng b gia cc cell; truyn nhn a m; h tr iu chnh cng sut da trn ts tn hiu/tp m; c th p dng k thut anten thng minh tng dung lng mng vvng ph sng (phin bn HSPA t Release 8 tr ln);h tr nhiu kiu chuyn giao giacc cell, bao gm soft-handoff, softer-handoff v hard-handoff;

UMTS cho php tc downlink l 0,384 Mbps (full mobility) v vi phin bnnng cp ln HSPA Release 6 hin nay, tc ln ti 14 Mbps (downlink) v 1,4 Mbps(uplink). D kin phin bn HSPA Release 8 ra mt vo nm 2009 (thm tnh nng

MIMO) th tc tng ng s l 42 Mbps & 11,6 Mbps.UMTS hon ton tng thch ngc vi GSM. Cc my handset UMTS thng htr c hai ch GSM v UMTS, do vy chng c th s dng vi cc mng GSM hinc. Nu mt thu bao UMTS ra khi vng ph sng ca mng UMTS v i vo vng phsng GSM th cuc gi ca thu bao c t ng chuyn giao cho mng GSM.

c bit, trong bng tn 1900-2200 MHz th WCDMA l cng ngh duy nht hinnay c thit b sn sng, c nhiu nh cung cp thit b sn xut v c th cung cpngay khi c n t hng. Mt khc, do quy m th trng ln v l cng ngh trng thnh nn WCDMA cng l mt trong nhng cng ngh c chi ph u t thpnht, em li hiu qu cao nht.

Tuy nhin UMTS cng c mt s nhc im. Chuyn giao cuc gi mi ch thchin c theo chiu t UMTS sang GSM m cha thc hin c theo chiu ngc li.Tn s cao hn mng GSM900 nn s lng trm BTS dy c hn do thi gian xydng mng lu hn v chi ph cao hn mng GSM. cung cp c dch v Video-on-demand, cc trm gc phi t cch nhau khong 1-1,5km; iu c th thc hin c khu vc th nhng s l khng kinh t khu vc nng thn.

5.2. IMT-2000 CDMA Multi-Carrier:


9/23

IMT-2000 CDMA Multi-Carrier cn c gi l IMT-MC hay CDMA2000 lcng ngh pht trin ln 3G t h CDMAOne (IS-95) bi 3GPP2. y l cng ngh cnhtranh trc tip vi cng ngh WCDMA trn th trng thng tin di ng.CDMA2000 c cc phin bn CDMA2000-1x (hay 1xRTT), CDMA2000-3x,CDMA2000 EV-DO, CDMA2000 EV-DV. CDMA2000 s dng cc cp sng mang c rng knh 1,25 MHz. Phin bn u tin CDMA2000 1x (hay IS-2000) s dng 1 cp

knh v tuyn 1,25 MHz chuyn ti 128 knh lu lng, cung cp tc downlink144 kB/s. Mc d CDMA2000 1x c cng nhn l 3G nhng nhiu ngi coi n l idin ca mng 2,5G.

CDMA2000 v CDMA2000 EV-DV s dng 3 knh 1,25 MHz tng tc .CDMA2000 EV-DV c tc downlink ln n 3,1 Mbps v uplink l 1,8 Mbps. Tuynhin c hai phin bn ny u khng cn c tip tc nghin cu, pht trin thngmi ho do cc nh khai thc CDMA2000 ln nht (nh Sprint Nextel v VerizonWireless) u la chn phin bn EV-DO. Hin nay cha c mng thng mi notrin khai hai phin bn ny.

CDMA2000 EV-DO li c nhiu revision khc nhau: Rev. 0, Rev. A, Rev. B, Rev.C. Tiu chun CDMA2000 EV-DO u tin c gi l Revision 0 c tc downlinkln n 2,4 Mbps v uplink l 153 kbps. CDMA2000 Rev. A c tc ln n 3,1 Mbpsdownlink v 1,8 Mbps uplink. Rev. B h tr tc uplink ln n 14,7 Mbps (3 knhsng mang). D kin n gia nm 2009 khi Rev. C hay cn gi l UMB ra i (s dngMIMO v OFDMA) s h tr tc downlink ln n 275 Mbps v uplink ln n 75MBps. Tc ny cho php ngi ta coi UMB l cng ngh ca mng 4G, snh ngangvi LTE ca dng cng ngh HSPA/WCDMA. Cng ging nh HSPDA, cc modem tRev. A tr ln ca CDMA2000 s dng chipset ca Qualcomm cng c kh nng x lng thi cuc gi voice bng chuyn mch knh v truy cp d liu bng chuyn mch

gi.Hin nay thit b CDMA2000 bng tn 1900-2200 MHz trn th gii mi ch c

1 nh khai thc duy nht l KDDI ca Nht Bn trin khai CDMA2000 bng tn 1900-2200 MHz. Thit b cho mng ny c KDDI t hng ring ca Toshiba nn khng

ph bin trn th trng. Thit b CDMA2000 trong bng 1900-2200 MHz c th s chc sau khi Rev. C (hay UMB) c thng mi ho vo cui nm 2009, u nm 2010.Tuy nhin th trng cho cng ngh CDMA2000 vn nh hn GSM/UMTS nay liang suy gim. Ti mt s nc, cc nh khai thc CDMA2000 cng ang chuyn hngsang HSPA. Ti Hn Quc, KTF v SK Telecom tuyn b ngng u t vo mng

CDMA2000 v bt u t u nm nay chuyn dn khch hng sang HSPA. TiAustralia, Telstra tuyn b s thu hp v ngng hot ng mng EV-DO v chuyndn khch hng sang mng HSPA. Cc nh sn xut cng khng cn quan tm nhiu nCDMA2000 na. Nokia tuyn b rt khi vic nghin cu pht trin CDMA v chtip tc kinh doanh cc sn phm CDMA mt s th trng trng im.

5.3. IMT-2000 CDMA TDD:H cng ngh CDMA TDD bao gm TD-CDMA v TD-SCDMA. Cng ngh TD-

SCDMA do chnh ph Trung Quc ch o Hc vin Cng ngh Vin thng Trung Qucv Cng ty Datang nghin cu, pht trin vi mc tiu khng l thuc vo cng ngh


10/23

Phng Ty nhm trnh phi tr mt khon ph bn quyn khng nh cho cc sng chca cc cng ty u-M ng thi thc y ngnh cng nghip in t-vin thng TrungQuc pht trin. Cng ngh TD-SCDMA cn ang c nghin cu pht trin v chac nc no ngoi Trung Quc d nh trin khai.

TD-CDMA hay cn gi l UMTS-TDD s dng chung mt knh v tuyn 5 MHzcho c ng ln v ng xung. Mi khung thi gian rng 10 ms chia thnh 15 time

slot. Cc time slot c phn b cho ng ln v ng xung theo mt t l c nh.Cng ngh truy cp CDMA c s dng trong mi time slot ghp knh cc dng dliu t cc tranceiver khc nhau.

Cng ngh TD-CDMA ch yu c s dng truy cp d liu internet bngthng rng ch khng dnh cho thoi. N ch yu c dng cho cc pico-cell v micro-cell c nhu cu d liu ln. Hin nay c khong 20 nc trin khai TD-CDMA ccthnh ph ln. Tuy nhin cng ngh ny cha thc s chn mui v quy m th trngcng nh s lng cc nh cung cp thit b cn nhiu hn ch.

5.4. IMT-2000 TDMA Single-Carrier:

Cng ngh TDMA Single-Carrier cn c gi l WUC-136, c pht trin ttiu chun IS-136 TDMA. N s dng cc knh c rng 30 KHz, 200 KHz v 1,6MHz. Cng ngh ny vn cn ang giai on nghin cu pht trin, cha c h thngno c trin khai thng mi, do cng t c kh nng chim lnh th trng.

5.5. IMT-2000 FDMA/TDMA:Cng ngh ny cn c tn gi l DECT. N c ETSI pht trin v c trin

khai mt s nc chu u, chu v chu M cho cc h thng in thoi khng dytng i c quan (PBX) v in thoi v tuyn ni th cng cng. Do c cng sut nh,vng ph sng hp (maximum 0,25W) nn cng ngh ny khng thch hp cho vic ph

sng ton quc n cc vng nng thn.5.6. IMT-2000 OFDMA TDD WMAN:Cng ngh ny da trn tiu chun 802.16e-2005 hay cn gi l Wimax di ng.

N c IEEE pht trin v ang c th nghim trin khai mt s nc. MobileWimax c mt s c im c bn nh sau:Thit k mng da trn cu trc All-IP; knhv tuyn c rng 3.5, 5, 7, 10, 20 MHz; song cng TDD; s dng iu ch OFDMA;tn s 2.3; 2.5; 3.5 GHz; t CW2 (2008) tr ln s h tr ngten thng minh (MIMO);tc (CW2) DL = 37.4 Mbps; UL=10 Mbps.Cng ngh Wimax ang c kh nhiu cc cng ty tham gia pht trin, c bit l cccng ty ang chim th phn khim tn trong mi trng thng tin di ng nh Nortelhay Motorola. Wimax l cng ngh c tim nng cnh tranh cao trong vic cung cp dchv truy cp khng dy bng rng. Hin nay Wimax forum c ti 469 thnh vin(7/2007) l cc nh sn xut chip/linh kin; cc nh cung cp thit b, cc nh cung cpdch v v cc nh cung cp ng dng.

Tuy nhin Mobile Wimax cng c mt s nhc im. Bng tn cho MobileWimax khng c thng nht cao trn ton cu nh UMTS nn quy m th trng b

phn mnh, dn n chi ph sn xut cao, thit b c gi thnh cao. Cng ngh Wimaxc pht trin t con s 0 nn khng tng thch vi bt k cng ngh no c trc .


11/23

Ngoi ra, vic pht trin Wimax xut pht t nhu cu cung cp dch v d liu bng rngkhng dy nn chi ph cung cp dch v thoi qua mng Wimax di ng l kh tnkm trong khi nhu cu ch yu ca ngi tiu dng hin nay vn l thoi (80-90% lulng ton mng), s lng ngi s dng laptop v PDA vn cn kh t.

Quan trng hn c l cng ngh Wimax khng c mt bng tn 1900-2200 MHz c cp php Vit Nam.

6. M HNH KIN TRC CA CC H THNG THNG TIN DI NG 3G6.1. Kin trc chung mng thng tin di ng 3G

Mng thng tin di ng 3G lc u s l mng kt hp gia cc vng chuyn mchgi (PS) v chuyn mch knh (CS) truyn s liu gi v ting.

Cc trung tm chuyn mch gi s l cc chuyn mch s dng cng ngh ATM.Trn ng pht trin n mng ton IP, chuyn mch knh s dn oc thay th bngchuyn mch gi. Cc dch v k c s liu ln thi gian thc (nh ting v video) cuicng s c truyn i trn cng mt mi trng IP bng cc chuyn mch gi. Hnh v

cho thy v d v mt kin trc tng qut ca thng tin di ng 3G kt hp vi CS v PStrong mng li.

Kin trc tng qut ca mt mng di ng kt hp c CS v PS

6.2. M hnh tham kho mng cdma2000.

Hnh v cho thy m hnh tham kho mng cho cdma2000. Cc k hiu trn hnhnh sau:


12/23

M hnh tham kho h thng mng cdma2000

- AAA = Authentication, Authorization v Accounting: Nhn thc trao quyn v thanhton. AAA l mt thc th m bo hot ng giao thc Internet h tr nhn thc, traoquyn v thanh ton. Cc chc nng IP c nh ngha trong cc ti liu IETF. AAAtng tc vi PDSN thc hin cc chc nng AAA trong vic h tr PDSN cho cctrm di ng yu cu. AAA tng tc vi cc thc th AAA khc thc hin cc chcnng khi AAA ti nh nm ngoi mng di ng ang phc v.

- AC = Authentication Center: Trung tm nhn thc. AC l thc th qun l thng tinnhn thc lin quan n MS. AC c th hoc khng t bn trong HLR> Mt AC c th

phc v nhiu HLR.

- BS = Base Station: trm gc. BS l thc th cung cp phng tin MS truy nhpmng bng ng v tuyn. MS bao gm BSC v BTS.

- BSC: Base Station Controller: B iu khin trm gc. BSC l thc th m bo iukhin v qun l i vi mt hay nhiu BTS. BSC trao i bn tin vi c BTS bv MSC.Lu lng v bo hiu lin quan vi iu khin cuc gi, qun l tnh di ng v qun lMS c th c truyn trong sut qua BSC

- BTS = Base Transceiver Station: Trm pht gc. BTS l thc th m bo cc kh nngtruyn dn qua im tham kho U.

- CDCP = Call Data Collection Point: im thu thp s liu cuc gi. CDCP l thc ththu thp thng tin chi tit v cuc gi khun dng IS-124.

- CDGP = Call Data Generation Point: im to s liu cuc gi. CDGP l thc th cungcp cc thng tin chi tit v cuc gi cho CDCP khun dng IS-124 . Tt c cc thngtin a n CDCP t CDGP phi khun dng IS-124.


13/23

- CDIS = Call Data Information: Ngun thng tin s liu cuc gi. CDIS l thc th cth c th l ngun thng tin chi tit v cuc gi. Thng tin ny c th mt khun dngring khng nht thit phi l IS-124.

- CDRP = Call Data Rating Point: im tnh cc s liu cuc gi. CDRP l thc thnhn thng tin chi tit cuc gi khun dng IS-124 khng tnh cc v cung cp thng tinlin quan n cc ph hoc c th tnh cc. Thng tin cc c b sung bng cch s

dng khun dng IS-124.- CF = Collection Funtion: Chc nng thu thp. CF l thc th chu trch nhim thu thpcc thng tin b chn cho c quan thi hnh php lut c u quyn hp php. Thngth CF bao gm:

+ Kh nng nhn v x l thng tin v ni dung cuc gi cho tng i tng bchn.

+ Kh nng nhn thng tin lin quan n tng i tng b chn (chng hn cucgi lin kt hoc khng lin kt)t chc nng mng v x l n.

- CSC = Customer Service Center: Trung tm phc v khch hng. CSC l thc th mti cc i din ca nh cung cp dch v nhn cc cuc gi in thoi t cc khchhng mun ng k cho vic bt u dch v v tuyn hoc yu cu thay i dch v hinc ca khch hng. CSC s dng giao din ring vi OTAF thc hin cc thay i linquan n mng v MScn thit cho vic thc hin yu cu cung cp dch v.

- DCE = Data Circuit Equipment: Thit b mch s liu. DCE l mt kt cui m bogiao din gia mng vi ngi s dng khng phi l ISDN.

- DF = Delivery Function: Chc nng chuyn. DF l mt thc th chu trch nhimchuyn cc cuc gi b chn n mt hay nhiu CF.

- EIR = Equipment Identity Register: B ghi nhn dng thit b. EIR l thc th m bo ghi li s nhn dng thit b ca ngi s dng.

- HLR = Home Location Register: B ghi nh v thung tr. HLR l b ghi nh v ghi li s nhn dng ca ngi s dng (chng hn s seri in t (ESN), s danh b ding (MDN), thng tin l lch, v tr hin thi v chu k u quyn)

- ISDN = Intergrated Service Digital Network: Mng s liu lin kt a dch v

- IP = Intelligent Peripheral: Ngoi vi thng minh. IP (ngoi vi thng minh) l thc ththc hin chc nng ti nguyn c bit nh: thng bo bng li (t bng), thu thp ccch s , thc hin vic chuyn i ting thnh vn bn hoc vn bn thnh ting , ghi vlu cc bn tin ting, cc dch v fax , cc dch v s liu

- IAP = Intercept Access Point: Ngoi vi thng minh. IAP m bo vic truy nhp ncc cuc thng tin n hoc t thit b, cc phng tin hay cc dch v ca mt itng b chn.

- IWF = Internetworking Function: Chc nng kt ni mng. IWF l mt thc th mbo vic bin i thng tin cho mt hay nhiu WNE. Mt IWFcos th c mt giao din


14/23

n mt WNE m bo cc dch v bin i. IWF c th lm tng thm mt giao dinc nhn dng gia hai WNE cung cp cc dch v bin i cho c hai WNE.

- MWNE = Managed Wireless Network: Mng v tuyn uc qun l. MWNE l thcth v tuyn bn trong thc th tp th hay mt thc th mng c th bt k cn qun lv tuyn ca OS hay bao hm c OS khc.

- MC = Massege Center: Trung tm nhn tin. MC l thc th lu ri pht cc bn tinngn. MC cng c th m bo cc dch v b sung cho dch v bn tin ngn (SMS).

- MS = Mobile Station: Trm di ng. MS l u cui c thu bao s dng truynhp mng giao din v tuyn. MS c th l thit b cm tay, dt trong xe hoc t cnh . MS l thit b v tuyn oc s dng kt cui ng truyn v tuyn ti thu

bao.

- MSC = Mobile Switching Center: Trung tm chuyn mch di ng. MSC l thc thchuyn mch lu lng c khi xng hoc kt cui MS. Thng thng mt MSCc kt ni vi t nht mt BS . N cng c th kt ni vi cc mng cng cng khc

(PSTN, ISDN) cc MSC khc trong mng hoc cc MSC cc mng khc .- MT = Mobile Terminal: u cui di ng. MT (u cui ) l kt cui MS c kh nngt truyn s liu m khng cn h tr giao din ngoi.

- NPBD = Number Portability Database: C s d liu tnh cm tay s. NPDB l mtthc th cung cp thng tin v tnh cm tay cho cc s danh b cm

- OSF = Operation Systemb Function: Chc nng h thng khai thc. OSF oc nhngha bi OSF ca TMN (mng qun l vin thng). Cc chc nng ny bao hm c ccchc nng lp qun l phn t, lp qun l mng, lp qun l dch v v lp qun l kinhdoanh phn b tt c cc chc nng ca h thng iu hnh (chng hn qun l s c,qun l hiu nng, qun l cu hnh, qun l thanh ton v qun l an ninh)

- OTAF = Over-The-Air-Service Function: Chc nng dch v khng gian. OTAF (chcnng dch v khng gian) l thc th giao din theo chun ring n CSC h tr cchot ng trang b dch v. OTAF giao din vi MSC pht n MS cc lnh cn thitcho vic thc hin cc yu cu trang b dch v.

- PDN = Public Data Networrk: Mng s liu cng cng. PDN m bo c ch truyn tis liu gi gia cc thc th mng thc hin x l c kh nng s dng cc dch v ny

- PDSN = Packet Data Servicing Node. PDSN l thc th cung cp chc nng giao thc

Internet vi mng di ng. PDSN thit lp, duy tr v kt cui cc phin ca lp on nivi MS. PDSN nh tuyn cc dgm IP n PDN. PDSN c th hot ng nh mt tcnhn MIP ngoi nh trong mng di ng . PDSN tng tc vi AAA m bo su htr nhn thc, trao quyn v thanh ton. PDSN c th giao tip vi mt hay nhiu mngIP hoc cng cng hoc Intranet m bo truy nhp mng IP.

- PSTN = Public Switched Telephone Network: Mng in thoi chuyn mch cng cng


15/23

- SCP = Service Control Point: im iu khin dch v. SCP l thc th hot ng nhmt c s d liu thi gian thc v h thng x l thao tc m bo chc nng iukhin dch v v s liu dch v.

- SN = Service Node: im dch v. SN l thc th m bo iu khin dch v, s liudch v, cc ti nguyn c bit v cc chc nng iu khin cuc gi h tr cc dchv lin quan n vt mang.

- SME = Short Message Entity: Thc th bn tin ngn. SME l thc th sp xp v giixp cc bn tin ngn. SME c th hoc khng oc t bn trong HLR, MC, VLR hayMSC.

- TA = Terminal Adapter: B thch ng u cui. TA l thc th chuyn i bo hiu vs liu ca ngi s dng gia giao din khng phi ISDN v giao din ISDN.

- TE = Terminal Equipment: Thit b u cui.

+ TE1 l u cui s liu m bo giao din ngi s dng ISDN- mng

+ TE2 l u cui s liu m bo giao din ngi s dng khng phi ISDN- mng- UIM = User Identity Module: M den nhn dng ngi s dng. UIM cha thng tinthu bao v c th cha thng tin c th thu bao. UIM c th hoc c kt hp bntrong u cui di ng hoc c th rt ra c.

- VLR = Visitor Location Register: B ghi nh v thng tr. VLR l b ghi nh v khcvi HLR n c MSC s dng thu nhn thng tin cho vic x l cuc gi n hoct thu bao khc. VLR c th hoc khng c t bn trong MSC.

- WNE = Wireless Network Entity: Thc th mng khng dy. WNE l thc th mng thc th tng th.

Kin trc chung ca mt h thng cdma2000 cng vi PDSN x l cc dch vgi (hnh v)

Kin trc chung ca h thng cdma2000


16/23

6.3. M hnh tham kho mng WCDMA

Hnh v cho thy cu trc mng c s W-CDMA trong 3GPP Release 1999 (tptiu chun u tin cho UMTS).

Kin trc mng WCDMA pht hnh nm 1999

Mng li gm cc trung tm chuyn mch di ng (MSC: Mobile SwitchingCenter) v cc nt h tr chuyn mch gi phc v (SGSN: Serving General PacketRadio Service Support Node). Cc knh thoi v s liu chuyn mch gi c kt nivi cc mng ngoi qua cc trung tm chuyn mch knh v nt chuyn mch gi cng:GMSC (khng oc ch ra hnh v) v GGSN. kt ni trung tm chuyn mchknh vi mng ngoi cn c thm phn t lm chc nng tgn tc mng (IWF). Ngoicc trung tm chuyn mch knh v nt chuyn mch gi, mng li cn cha cc c s

d liu cn thit cho cc mng di ng nh: HLR, AUC v EIR (hai phn t cui cngkhng oc ch ra hnh v).

mng truy nhp v tuyn cha cc phn t sau:

- RNC: Radio Network Controller: B iu khin mng v tuyn, ng vai trnhu BSC cc mng thng tin di ng

- Nt B ng vai tr nh cc BTS cc mng thng tin di ng

- UE: User Equipment - thit b ca ngi s dng .

UE bao gm thit b di ng (ME) v modun nhn dng thu bao UMTS (USIM).USIM l vi mch cha mt s thng tin lin quan n thu bao cng vi kho bo an(ging nh SIM GSM) . Giao din gia UE v mng gi l giao din Uu. Trong ccquy nh ca 3GPP, trm gc c gi l nt B. Nt B c ni n mt b iu khintrm v tuyn RNC. RNC iu khin cc ti nguyn v tuyn ca cc nt B c nivi n. RNC ng vai tr nh BSC GSM. RNC kt hp vi cc nt B ni vi n cgi l h thng con mng v tuyn RNS(Radio Network Subsystem). Giao din giant B v RNC gi l giao din Iub. Khc vi giao din Abis tng ng GSM , gioa


17/23

din Uib c chun ho hon ton v m, v th c th kt ni nt B vca mt nhsn xut ny vi RNC ca mt nh sn xut khc.

Khc vi GSM, cc BSC trong mng W-CDMA khng ni vi nhau, trongmng truy nhp v tuyn ca UMTS (UTRAN) c c giao din gia cc RNC . Giaodin ny gi l Iur c tc dng h tr tnh di ng gia cc RNC v chuyn giao giacc nt B ni n cc RNC khc nhau.. Bo hiu Iur h tr chuyn giao.

UTRAN c ni n mng li qua giao din Iu. Giao din Iu c hai phn t khcnhau: Iu-CS v Iu-PS. Kt ni UTRAN n phn chuyn mch knh c thc hin quagiao din Iu-CS, giao din ny ni RNC n mt MSC/VLR. Kt ni UTRAN n phnchuyn mch gi c thc hin qua giao din Iu-PS, giao din ny ni RNC n mtSGSN

T hnh v ta thy tt c cc giao din UTRAN ca 3GPPP pht hnh nm 1999u c xy dng trn c s ATM. ATM c chn v n c kh nng h tr nhiulai dch v khc nhau (chng hn tc bt kh bin cho cc dch v trn c s gi vtc bt khng i cho cc dch v chuyn mch knh). Mt khc mng li s dngcng mt kin trc c s nh kin trc ca GSM/GPRS, nh vy cng ngh mng lihin c c th h tr cng ngh truy nhp v tuyn mi. Chng hn cung c th nngcp mng li hin c h tr UTRAN sao cho mt MSC c th ni n c UTRANRNC v GSM BSC.

Trong thc t cc tiu chun UMTS cho php h tr chuyn giao cng t UMTSn GSM v ngc li. y l mt yu cu rt quan trng v cn phi c thi gian trin khai rng khp UMTS nn s c khong trng trong vng ph sng ca UMTS vv tgh thu bao UMTS phi c kh nng nhn c dch v vng ph sng caGSM. Nu UTRAN v GSM BSS c ni n cc MSC khc nhau, chuyn giao giacc h thng t c bng cch chuyn giao gia cc MSC. Nu gi thit rng nhiuchc nng ca MSC/VLR ging nhau i vi UMTS v GSM, MSC cn phi c khnng h tr ng thi c hia kiu dch v. Tng t hon ton hp l khi gi thit rngSGSN phi c kh nng h tr ng thi kt ni Iu-PS n RNC v Gb n GPRSBSC.

Trong hu ht sn phm ca nh sn xut, nhiu phn t mng ang c nng cp h tr ng thi GSM/GPRS v UMTS. Cc phn t mng ny bao gm MSC/VLR,HLR, SGSN v GGSN. i vi nhiu nh sn xut, cc trm gc c trin khai doGSM/GPRS c thit k c th nng cp chng h tr cho c GSM v UMTS.

i vi mt s nh sn xut BSC oc nng cp hot ng nh c hai GSM BSC vMT RNC. Tuy nhin cu hnh ny rt him. Yu cu giao din v cc chc nng khcnhau (nh chuyn giao mm)ca UMTS RNC chng t rng cng ngh ca n honton khc vi GSM BSC. V th thng thng ta thy cc UMTS RNC v GSM BSCtch bit.


18/23

Kin trc mng W-CDMA phat hanh 4

Hnh v cho thy kin trc c s ca mng W-CDMA pht hnh 4. S khc nhauc bn gia pht hnh 1999 v pht hnh 4 l ch khi ny mng li l mng phn b.

Thay cho vic c cc MSC chuyn mch knh truyn thng nh kin trc trc, kintrc chuyn mch phn b c a vo.

V cn bn, MSC c chia thnh MSC Server v cng cc phng tin (MGW:Media Getway). MSC cha tt c cc phn mm iu khin cuc gi, qun l di ng c mt MSC tiu chun. Tuy nhin n khng cha ma trn chuyn mch. Ma trn chuynmch nm trong MGW c MSC Serve iu khin v c th t xa MSC Serve.

Bo hiu iu khin cc cuc gi chuyn mch knh c thc hin gia RNC vMSC Serve. ng truyn cho cc cuc gi chuyn mch knh c thc hin gi RNCv MGW. Thng thng MGW nhn cc cuc gi t RNC v nh tuyn cc cuc gi

ny n ni nhn trn cc ng trc gi. Trong nhiu trng hp ng trc gi. Trongnhiu trng hp ng trc gi s dng giao thc truyn ti thi gian thc (RTP: RealTime Transport Protocol)tren giao thc IP (Internet Protocol). Theo hnh v ta thy lulng s liu gi t RNC i qua SGSN v t SGSN n GGSN trn mng wongf trcIP. Nu gi thit rng c s liu v ting u c th s dng phng thc truyn qua IP

bn trong mng li , th c th cu trc mt ng trc h tr c hai dch v ny. Tuynhin iu ny i hi u t v chi ph cho khai thc rt ln so vi trng hp s dngcc mng ng trc tch bit cho chuyn mch knh v gi.

ni m cuc gi cn chuyn n mt mng khc, PSTN chng hn, s c mt

cng cc phng tin khc (MGW) c iu khin bi MSC Serve cng (GMSC serve).MGW ny s chuyn thoi wocj ng gi thnh PCM tiu chun a n PSTN. Nhvy chuyn i m ch cn thc hin ti im ny. V d: Gi thit nu ting giao dinv tuyn c truyn ti tc 12,2 kbit/s th tc ny phi wocj chuyn vo 64 kbit/s MGW gioa tip vi PSTN. Truyn ti kiu ng gi ny cho php tit kim ng k rng bng tn nht l khi cc MGW cch xa nhau.

Giao thc iu khin gia MSC Serve hoc GMSC Serve vi MGW l giao thcITU H.248. Giao thc ny c ITU v IETF cng tc pht trin. N c tn l iu khin


19/23

cng cc phng tin(MEGACO: Media Getway Control). Giao thc iu khin cuc gigi MSC Serve v GMSC Serve c th l mt giao thc iu khin cuc gi bt k.3GPP ngh s dng giao thciu khin cuc gi c lp vt mang (BICC:BeareIndepentdent Call Cotrol) c xy dng trn c s khuyn ngh Q.1902 ca ITU.

Trong nhiu trng hp MSC Serve h tr c cc chc nng ca GMSC Serve,Ngoi ra MGW c kh nng giao din vi tt c RAN v PSTN. Khi ny cuc gi n

hoc t PSTN c th chuyn ni ht, nh vy c th tit kim ng k u t. V d ta xttrng hp khi mt RNC c t ti thnh ph A v oc iu khin bi mt MSC tti thnh ph B. Gi s thu bao thnh ph A thc hin cuc gi ni ht. Nu khng ccu trc phn b, cuc gi cn chuyn ti thnh ph A n thnh ph B (ni c MSC) u ni thu bao PSTN ti chnh thnh ph A. Vi cu trc phn b, cuc gi c thc iu ti MSC Serve thnh ph B nhng ng truyn cc phng tin thc t cth vn thnh ph A, nh vy gim ng k yu cu truyn dn v gi thnh khai thcmng.

T hnh v ta thy HLR cng c th c gi l Serve thu bao ti nh (HSS:

Home Subscriber Serve)HSS v HLR c chc nng tng ng, ngoi tr giao din viHSS l giao din trn c s truyn ti gi (IP chng hn)trong khi HLRs dng giao dintrn c s bo hiu s 7. Ngoi ra cn c c giao din gi SGSN vi HSS/HLR v giaGGSN vi HSS/HLR.

Rt nhiu giao thc c s dng bn trong mng li l c giao thc trn c s gis dng hoc IP hoc ATM. Tuy nhin mng phi giao tip vi cc mng giao tiptruyn thng qua vic s dng cc cng cc phng tin . Ngoi ra mng cng phi giaodin vi cc mng SS7 tiu chun. Giao din ny c thc hin thng qua cng SS7(SS7 GW). y l cng m mt pha n h tr truyn ti bn tin SS7 trn ng truyn

ti SS7 tiu chun , phi kia n truyn ti cc bn tin ng dng SS7 trn mng gi (IPchng hn). Cc thc ht nh MSC Serve, GMSC Serve v HSS lin lc vi cng SS7bng cch s dng cc giao thc truyn ti c thit k c bit mng cc bn tinSS7 mngIP. B giao thc ny c gi l Sigtran.

Bc pht trin tip theo ca UMTS l kin trc mng a phng tin IP (hnhv)Bc pht trin ny th hin s thay i ton b m hnh cuc gi. y c ting vs liu c x l ging nhau trn ton b ng truyn t u cui ca ngi s dngn ni nhn cui cng. C th coi kin trc ny l s hi t ton din ca ting v sliu.


20/23

Kin trc mng a phng tin IP ca 3 GPPP

T hnh v ta thy ting v s liu khng cn cc giao din cch bit ; ch c mt

giao din Iu duy nht mang tt c cc phng tin . Trong mng li giao din ny ktcui tai SGSN v khng c MGW.

Mt c im quan trng ca kin trc IP l thit b ca ngi s dng c tngcng rt nhiu. Nhiu phn mm c ci t UE. Trong thc t UE h tr giao thckhi u phin (SIP: Session Initiation Protocol). UE tr thnh mt tc nhn ca ngi sdng SIP. Nh vy, UE c kh nnng iu khin cc dch v ln hn trc rt nhiu.

CSCF qun l vic thit lp, duy tr v gii phng cc phin a phng tin n vt ngi s dng. N bao gm c chc nnng nh: bin dch v nh tuyn. CSCF hotng nh mt i din Serve/h tch vin.

SGSN v GGSN l cc phin bn tng cng ca cc nt oc s dng GPRSv UMTS pht hnh 1999 v 4. im khc nhau duy nht l ch cc nt ny khng chh tr dch v s liu gi m c dch v chuyn mch knh (ting chng hn). V th cnh tr cc cc kh nng cht lng dch v (QoS) hoc bn trong SGSN v GGSN hoct nht cc b nh tuyn kt ni trc tip vi chng.

Chc nng ti nguyn a phung tin(MRF) l chc nng lp cu hi ngh c sdng h tr cc tnh nng nh t chc cuc gi nhiu pha v dch v hi ngh.

Cng bo hiu truyn ti(T-SGW) l mt cng bo hiu SS7 m bo tng tc

vi mng tiu chun ngoi nh PSTN. T-SGW h tr cc giao thc Sigtran. Cng bohiu chuyn mng (R-SGW) l mt nt m bo tng tc bo hiu vi cc mng ding hin c s dng SS7 tiu chun.

MGW thc hin tng tc vi cc mng ngoi mc ng truyn a phngtin. MGW kin trc mng ca pht hnh 3GPP 5 c chc nng ging nh pht hnh4. MGW c iu khin bi chc nng cng iu khin cc phng tin (MGCF). Giaothc iu khin gia cc thc th ny l ITU-T H.248.


21/23

Cu trc IP l mt tng cng ca mng pht hnh 1999, hoc 4. N a thmvo mt vng mi trong mng l vng a phng tin IP (IM: IP Multimedia). Vngmi ny cho php mang c thoi v s liu qua IP trn ton tuyn ni n my cm tay.Vng ny s dng vng chuyn mch gi PS cho mc ch truyn ti. Kin trc ny cxy dng trn cc cng ngh gi v in thoi IP cho ng thi cc dch v thi gian thcv khng thi gian thc. Kin trc cho php chuyn mng ton cu v tng hp vi cc

mng ngoi nh: cc mng thng tin di ng th h hai hin c, cc mng s liu cngcng, cc mng VoIP v cc mng a phng tin.

7. Cc loi thit b u cui cho 3G:+ Ting: 8/16/32 kbit/s

+ S liu (chng hn PCM CIA).

- Truyn dn s liu bng m em ting cho cc tc :1,2 kbit/s, 2,4 kbit/s, 4,8kbit/s, 9,6 kbit/s, 19,2 kbit/s, 28,8 kbit/s.

- Truyn dn s liu s chuyn mch theo mch cho cc tc : 64 kbit/s; 128kbit/s; u cui video thp hn 2 Mbit/s

+ nh tnh (u cui cho PSTN)

+ Hnh nh di ng: c phn loi theo cc cp bc cht lng (32/64/128 kbit/s)

+ Thoi c hnh cht lng cao vi tc khng thp hn 128 kbit/s

Thit b u cui ging my thu hnh

+ u cui kt hp my thu hnh v my vi tnh

+ My thu hnh cm tay c kh nng thu c MPEG

Thit b u cui s liu gi:

+PC c ca thng tin cho php :

- in thoi c hnh

- Vn bn, hnh nh, truy nhp c s d liu, video

+ u cui PDA

- PDA tc thp

- PDA tc cao hoc trung bnh

- PDA kt hp vi sch in t b ti

+ My nhn tin hai chiu

+ Sch in t b ti c kh nng thng tin

Phn b tn s ca IMT-2000 cho chu u, Nht Bn, Hn Quc v M c chonh sau:


22/23

Chu u s dng h thng th h hai l DCS (Digital Cellular System - H thngmng t ong s) 1800 vi bng tn 1710 1755 Mhz cho ng ln v 1805 1850 Mhz ng xung. Chu u v hu ht cc nc chu bng tn IMT-2000 l 2x60 Mhz(1920 1980 Mhz cng vi 2110 2170 Mhz) c th s dng cho W-CDMA FDD.Bng tn s dng cho TDD Chu u thay i, bng tn c cp theo giy php c thl 25 Mhz cho s dng TDD 1900 1920 MHz v 2020 2025 MHz. Bng tn cho cc

ng dng TDD khng cn xin php (SPA: Shelf Provie Application - ng dng t cp)c th l 2010 2020 MHz. Cc h thng FDD s dng cc bng tn khc nhau chong ln v ng xung vi phn cch l khong cch song cng, cn h thng TDDs dng cng tn s cho c ng ln v ng xung.

Nht Bn s dng h thng th h hai l PDC, cn Hn Quc s dng h thng thh hai l IS-95 cho c khai thc t ong ln PCS. n nh ph PCS Hn Quc khc vin nh ph PCS M, v th Hn Quc c th s dng ton b ph tn quy nh caIMT-2000. Nht Bn mt phn ph tn ca IMT-2000 T c s dng cho PHS.

M khng cn ph tn mi cho cc h thng thng tin di ng th h ba. Cc

dch v ca th h ba s c thc hin trn c s thay th ph tn ca h thng thngtin th h ba bng ph tn ca h thng PCS th h hai hin ti.

Trung Quc ph tn dnh trc cho PCS (Persional Comminication System: Hthng thng tin c nhn) v WLL s dng mt phn ph tn ca IMT-2000 mc d chngcha c n nh cho hng khai thc no. Ph thuc vo quyt nh v phn nh tn s,s c 2x60 MHz c s dng cho W-CDMA Trung Quc. Ph tn cho TDD cng sc s dng Trung Quc.

Cc nc bt u cp php cho s dng ph tn ca IMT 2000. Giy phpu tin c Phn lan cp vo thng 3/1999, sau l Ty Ban Nha. Mt s nc cngc th i theo quan im cp php ging nh GSM c cp php Chu u. Tuy nhinmt s nc bn u gi tn ph cho IMT-2000 ging nh M bn u gi ph tn choPCS (nc Anh chng hn)

8 . Cng ngh 3G no cho Vit NamChun 3G m B Thng tin v Truyn thng Vit Nam cp php l chnh l

WCDMA bng tn 2100 MHz. Cng ngh ny hot ng da trn CDMA v c khnng h tr cc dch v a phng tin tc cao nh video, truy cp Internet, hi thoc hnh... WCDMA nm trong di tn 1920 MHz -1980 MHz, 2110 MHz - 2170 MHz...y l s la chn ng n bi theo s phn tch trn ta thy rng bng tn ccp php (1900-2200 MHz) cho mng 3G Vit Nam hin ti mi ch c cng nghWCDMA l sn sng. Cc cng ngh khc, k c CDMA2000-1x EV-DO l cha snsng on bng tn ny vo thi im hin nay. Cng ngh EV-DO sm nht cng chc kh nng c mt bng tn 1900-2200 MHz vo nm 2010 khi Rev. C c thngmi ho. Mc d mt s nc trn th gii cp php bng tn 3G theo tiu ch c lp vcng ngh (khng gn vic cp bng tn vi bt k cng ngh no) nhng thc t trinkhai nhiu nc cho thy trong bng tn 1900-2200 MHz, cng ngh WCDMA/HSPA


23/23

vn l cng ngh ch o, c a s cc nh khai thc la chn. Quy m th trng lnca cng ngh ny cng m bo rng n s c tip tc pht trin trong tng lai.

Cng ngh W-CDMA c cc c tnh nng c s sau:

+ Hot ng CDMA bng rng vi bng tn 5MHz;

+ Lp vt l linh hot tch hp tt c cc tc trn mt sng mang;

+ Ti s dng bng 1.Ngoi ra cng ngh ny c cc tnh nng tng cng sau:

+ Phn tp pht;

+ ng ten thch ng

+ H tr cc cu trc thu tin tin.

W-CDMA nhn c s ng h ln nht trc ht nh tnh linh hot ca lp vt ltrong vic h tr cc kiu dch v khc nhau, c bit l cc dch v tc bt thp v

trung bnh. Nhc im ca W-CDMA l h thng khng cp php trong bng tn TDDvi pht thu lin tc, cng ngh W-CDMA khng to iu kin cho cc k thut chngnhiu cc phng tin lm vic nh my in thoi khng dy. u im ca cng nghny l h tr nhiu mc tc khc nhau: 144Kbps khi di chuyn nhanh, 384Kbps khi i

b (ngoi tri) v cao nht l 2Mbps khi khng di chuyn (trong nh). Vi tc cao,WCDMA c kh nng h tr cc dch v bng rng nh truy cp Internet tc cao, xem

phim, nghe nhc vi cht lng khng thua km kt ni trong mng c dy. WCDMAnm trong di tn 1920MHz -1980MHz, 2110MHz - 2170MHz.

Documents

Tim Hieu Cong Nghe 3g