TỔNG QUAN VỀ CDMA

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TNG QUAN V CDMA. Nhm thc hin : 0612280 Trn Xun Nam 0612252 Trn Kinh L 0612271 Phm Quc M - Nguyn Quang Minh GVHD: L Tr Anh. NI DUNG. Tng quan CDMA. Lch s pht trin a truy cp Khi nim CDMA Cc dchv cung cp CDMA Vit Nam. - PowerPoint PPT Presentation

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Slide 1

TNG QUAN V CDMA

Nhm thc hin:0612280 Trn Xun Nam0612252 Trn Kinh L0612271 Phm Quc M- Nguyn Quang MinhGVHD: L Tr Anh

Tng quan CDMALch s pht trina truy cpKhi nim CDMACc dchv cung cp CDMA Vit NamNI DUNGTNG QUAN CDMA Lch S Pht TrinNm 1995, CDMA IS-95A l phin bn u tin c trin khai thng mi ti Hng Kng , tc truyn 14kbit/giyNm 1996 CDMA bt u thng tr trn th trng Bc M.Nm 1997, IS - 95B c a ra , tc truyn n 64 kbit/giy , s thu bao CDMA trn ton th gii vo xp x 8triu thu bao. Nm 1998, CDMA 2000 1x h tr c thoi v d liu c a vo d tho IMT2000 , nh ngha cho tiu chun truyn thng th h th 3 (3G) , thu bao CDMA ln n 24 triu ngi trn ton th gii.

TNG QUAN CDMA Lch S Pht TrinNm 1999, CDMA 2000 1x c cng nhn l 3G v chnh thc c cng b. Cui nm 1999, th gii c hn 50 triu thu bao CDMA.Nm 2000, 2 nh khai thc hng u ti Hn Quc l SK Telecom v LG Telecom trin khai thng mi h thng CDMA 2000 1x u tin trn th gii. Th gii c 80 triu thu bao CDMA.Nm 2001, CDMA 2000 1x EV tr thnh mt chun ca 3G.Ch trong 3 thng, t thng 6 n thng 9/2002: t 127 triu thu bao, CDMA vt qua con s 134 triu thu bao

TNG QUAN CDMA Lch S Pht TrinBng tng qut s pht trin ca CDMA

Hnh nh v a truy cp

Cc trm di ng v trm gcTNG QUAN CDMA a Truy Cp TNG QUAN CDMA a Truy Cp Cng ngh FDMA

rng bng tn c cp pht cho h thng B Mhz c chia thnh N bng tn con , mi bng tn c n nh l 1 knh ring .TNG QUAN CDMA a Truy Cp V d

TNG QUAN CDMA a Truy Cp Cng ngh TDMA

Cc trm u cui ln lt thc hin truyn d liu ( khng lin tc )TNG QUAN CDMA a Truy Cp

V d TNG QUAN CDMA Khi NimCDMA l cch thc lin lc bng cch s dng nhiu m khc nhau . tng ca CDMA ging nh cch thc ni chuyn ca con ngi. Ch nhng ngi s dng chung 1 ngn ng mi hiu c nhau .

TNG QUAN CDMA Khi NimMinh ha bng hnh nh :

trm 1 v trm 2 khng cng m vi nhau nn khng th hiu nhau TNG QUAN CDMA Khi NimV d th hin tng ca CDMA

Gi s c 4 trm l 1,2,3,4 s dng chung 1 knh truyn . D liu ca cc trm ln lt l d1,d2,d3,d4 . M ca cc trm ln lt l c1,c2,c3,c4 TNG QUAN CDMA Khi NimM ca cc trm c tnh cht :Nu nhn m ca 1 trm vi m ca 1 trm khc th nhn c kt qu l 0 ( v d : c1.c2 = 0 )Nu nhn m ca 1 trm vi chnh n th kt qu nhn c l 4 . ( v d : c1.c1 = 4 ) truyn d liu , cc trm nhn d liu ca mnh vi m, tc l trm 1 s truyn ( d1.c1 ) v tng t cho cc trm cn li D liu trn ng truyn l tng hp tt c cc d liu gi i ca cc trm

TNG QUAN CDMA Khi NimMt trm no lng nghe 1 trm khc th phi bit m ca trm m mnh mun lng nghe .

Trm 1 mun bit trm 2 ni g , n s nhn d liu trn ng truyn vi m ca trm 2.Lc ta c :

( d1.c1 + d2.c2 + d3.c3 + d4.c4 ) . c2 == d1.c1.c2 + d2.c2.c2 + d3.c3.c2 + d4.c4.c2 = d1.0 + d2.4 + d3.0 + d4.0= 4.d2

Nh vy trm 1 ch cn chia kt qu cho 4 th s bit trm 2 gi i d liu g

TNG QUAN CDMA Khi NimCHIPMi trm c cp cho 1 m , m ny c gi l cc chip . Trong v d trn th c1,c2,c3,c4 c gi l cc chip.

Tnh cht ca chui m ( chui cc chip )Mi chui m c N thnh phn , vi N l s trm c trong mngNu nhn 1 s cho 1 chui m th mi thnh phn trong chui m c nhn vi s 2.[+1 -1 +1 -1] = [+2 -2 +2 -2]Nu nhn 1 chui m vi chnh n th c kt qu l N[+1 -1 +1 -1].[+1 -1 +1 -1] = [+1 +1 +1 +1] = 4Nu nhn 1 chui m vi 1 chui m khc th kt qu l 0 [+1 +1 -1 -1].[+1 +1 +1 +1] = [+1 +1 -1 -1] = 0Nu cng 2 chui m th c 1 chui m khc [+1 -1 +1 -1].[+1 +1 +1 +1] = [+2 0 +2 0]

TNG QUAN CDMA Khi Nim

Ta c th t cho 4 trm trn cc m nh sau :c1=[+1 +1 +1 +1]c2=[+1 -1 +1 -1]c3=[+1 +1 -1 -1]c4=[+1 -1 -1 +1]TNG QUAN CDMA Khi Nim Biu din d liu :Nu trm cn truyn bit 0 th s c m ha thnh -1 , bit 1 c m ha thnh +1 v nu khng truyn th s c m ha l 0

TNG QUAN CDMA Khi Nim M ha v gi m :Xt v d trn trong qu trnh truyn 1 bit Gi s trm 1 v 2 truyn bit 0 , trm 3 khng truyn v trm 4 truyn bit 1 Mi trm nhn d liu cn truyn vi m ca mnh v gi ln ng truynTa c kt qu nh sau :

TNG QUAN CDMA Khi Nim Trm 3 mun ly d liu ca trm 2 . Trm 3 nhn d liu trn ng truyn : [-1 -1 -3 +1] vi m ca trm 2 [+1 -1 +1 -1]Ta c : [-1 -1 -3 +1].[+1 -1 +1 -1] == [-1 +1 -3 -1]= -4 => 4.d2 = -4 => d2 = -1 . Vy trm 2 gi i bit 0

TNG QUAN CDMA Khi Nim Pht sinh chui m : pht sinh chui m , ta s dng bng Walsh ( l 1 ma trn c s dng bng s ct )

TNG QUAN CDMA Cc dch v cung cp CDMA Vit Nam Hin nay Vit Nam c 7 nh cung cp dch v in thoai di ng Trong , S-Telecom(S-Fone),EVN-Telecom s dng cng ngh CDMA, Mobifone, Vinaphone, GTel v Vietel s dng cng ngh GSM,H Ni Telecom (HT Mobile) chuyn t cng ngh CDMA sang eGSM.

TNG QUAN CDMA Cc dch v cung cp CDMA Vit Nam S-Fone

S-Fone tin hnh nng cp mng CDMA 2000-1X ln cng ngh th h 3 (3G)CDMA 2000-1X EVDO ngi khch hng Vit Nam sm c tn hng cc dch v gi tr gia tng cao cp trn nn bng thng rng TNG QUAN CDMA Cc dch v cung cp CDMA Vit Nam n u cho vic nng cp cng ngh ny, S-Fone tung ra th trng cng mt lc 5 mu in thoi di ng cao cp nht t trc n nay, gm: Samsung SCH- S380, SCH-V740, LG SB130, SKY IM - 8400 v SKY IMB-1000.im chung nht ca 5 model ny l u h tr chun CDMA 2000 1x/EVDO, tch hp nhiu tnh nng cao cp v c o.

Samsung SCH- S380TNG QUAN CDMA Cc dch v cung cp CDMA Vit Nam EVN-Telecom

Bn thn CDMA l s thun li cho s pht trin ln mng 3G do khng phi thay i li ton b thit b, gy tn km v lng ph nh mng GSM. V vy, khi c nhu cu pht trin, EVN Telecom ch cn u t mt phn vn khng ln (lp t cc trm thu pht EVDO) l c th sn sng cung cp cho khch hng s cc dch v 3G.

TNG QUAN CDMA Cc dch v cung cp CDMA Vit Nam Va qua, EVN Telecom (Cng ty Thng tin Vin thng in lc) chnh thc a vo khai thc 2 dch v in thoi mi: Ecom v Ephone ti mt s tnh thnh ph. C 2 dch v ny u s ng cng ngh tin tin CDMA 2000 1X, tn s 450 MHZ c kh nng cung cp dch v 3G (EV - DO).

Ecom

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