Truyền thông tin và những ứng dụng của mạng Vanet.PDF

CHUONG 1. Ting quan ve r ha th6ng mang Vanet CHU • ONG 1. TONG QUAN Vt HE THONG MANG VANET 1.1. GIO1 THIEU CHUNG Vt MANG VANET 1.1.1. Khdi niflm VANET (VEHICULAR AD-HOC NETWORKS) li mpg trong da cic xe (vehicule) se duqc trang bj thiet bj thu/phit, chang se ter thinh cic node nhu trong mpg ad-hoc. Cic xe se lien lac vai nhau (Car-to-Car Communication), hay M2M (machine-to-machine communication) de chia se thong tin lin nhau. ThOng tin ye traffic, ye tinh trang kit xe, thong tin ye tai not giao thong, nguy hiem can trinh M0 chile xe ding c6 the trb thinh mOt Relay Node a chuyen tii th8ng tin cho xe khic VANET sfr chum chuin Wifi 802.11. 1.1.2. Tgi sao eó h? thong Vanet? — Cong nghiap xe ngiy ding phit trier. — S6 vu tai non giao thong, On tic ngiy tang tang. — Cic phuang flan thiet bj phut vu cho giao thong chtra tai uu 1.2. NGUYEN TAC CO BAN VA MACH Marc Khii niem co bin cda VANET la khang phi= tap: thuc thi tram deg nghe WLAN dian rang vi khong qui dit, tart li ket n6i giva cic may tinh vii nhau hoot vii intemet, vi vai nhieu cii lien no duqc ip dung len xe cO. Diu lien, thong to xem x& den co hOi. Neu cic phuong den c6 the truyen thong tnrc tap vii nhau vi v6i co so ha Ling, meo hinh hob toin moi cho nheng (mg clang an toin cba phuang den 06 the se duqc hinh thinh. Thtl hai, nheng thich thac mad da thrqc too ra Uri phuong tian tee do) cao vi mad trubng tic dOng llrc lan. Thir ba, nheng yeu ciu can phii c6 Ye an loin d6i yeti cic frog dung mad, bao gim nheng 10 vqng mad cho phin phii gei tin cao vi dO trg gei tin thip. Han naa, phin (mg mb flint cM khich hang vi su gin sit caa ha thing giim sit dem lei 10 vqng cao ye an ninh vi sir rieng tut. Them chi ngiy nay, chiec xe too ra vi phial tick luqng bfm de lieu, mac thl de lieu nay thubng china trong mOt chi& xe duy nhit. ce VANET, dim nhin (kha Whig nh$n biet xung quanh) cue cic phuang tian giao thong vi cue lii ACC duqc tang len ding Ice. Truyen thong VANET c6 the thuc hian true till) gala cic xe nhu Owen th8ng "mOt buoc", hoot phuang tian ce the truyen lai bin tin, do da cho phdp truyen thong "da Woe. De tang yang phtl sang hoc dO ben yang cult truyen thong, chuyen tie') lc ben thrtmg c6 the duqc trien khai. Co so ha tang ben throng clang c6 the duvc sfr dung nhu mOt deg vio internet vi do da de lieu vi th8ng tin net cinh c6 the duqc thu thap, luu Ire vi "6 mqi nor, vi du ca so ha ling mang cue coag nghe ditat town dim may sip tad. 2 .•••  • 1, %••• ■ -• / /1111 / ' r ollw — •• ■ ••411111 " 111 " 1111111 1 ■ ___ rrn  4 40 CHISONG 1. Tang quan ve he thong mung Vanet N6 dim bao ring mpg lien kit gift cic xe se thfic diy manh me b6i su phong phi caa cic Ung dung co the dugs kich hoot. Truoc het, cic ting dt,mg an toan chb dOng, tirc la cic ting dung phong ch6ng tai nun se duqc hiding lqi mOt cich true dip tfr truyin thong. Thir hai, bang cich thu thilp dtt lieu twig thii giao &Ong ter mOt yang rung han, luu luqng giao thong c6 the dirge cal thief', thstri gian di chuyin c6 the duqc giim cling nhtr nheng lchi thii hY cic phuang lien. Nhu n6 di duqc ghi chinh xic nhu cic nguyen 1 cult he th6ng giao th8ng thong minh (Intelligent Transportation System World Congress) nam 2008: Tiet kiem th6i gian. Cic 16p (mg dung "an tan" vi "hien qui" c6 the duqc sfr dung de phan loci cdc Ung dung dlra tren mix dich chinh cia chimg. Tuy nhien, cic khia can't an toile vi hieu qui khong the quan niem nhu cic tinh Wing tech r6i hoiln town. R8 tang, tai min xe c6 the din den tic nghen giao thong. MOt bin tin th8ng bio mOt vu tai non ce the duqc xem nhu la mOt thong bio an town * diem quan sit caa xe gin d6. Ban tin Wang tu c6 the duqc nhin cic phuong lien 8 xa han nhu mOt diu veto de tinh toin mOt 10 trinh thay the trong mOt (mg dung hieu qui giao thong. Ifinh 1.1 Bilu (IS minh has cdc cdnh bdo nguy hiim Trong khii niem don giin, thiet ke vi tan khai cic VANET la met luc kq diy thich thirc ve ky thust va kinh to Mich thirc chinh ve ky thuUt bao g6m cic vin de sau: — Cie Sc il dam c6 ham cda kenh v8 twin dien. Cic kich ban hien nay mia VANET vbi nhieu die diem khong thu0n lqi cho vies phit trien truyen th8ng khong diy, vi du: nhieu doi tuqng phin inh co the lam suy giam dO mph vi chit luqng ctia song tin hieu nhen duqc. Ngoai ra, do tinh di dOns cia cic dii 3 CHISONG 1. TOng quan ve hg thong mong Vanet trung xung quash ho#c chting tv gfri vi tv nkftn, hilt' Ong mb din phii duqc dua vio sv tinh toin. — Thies mOt sv quin  trung trvc tory& vi  don vj phOi bqp. Vilc sir dtmg ding bing vi hilu qui bang thong mkt kenh lchang day li mOt nhilm vp kh6 khan trong mOt mong ur t6 chrrc vi phan cep hoin toin. Vi$c thieu mOt thvc the c6 khi Wing ding bO h6a vi quip cic sv ki/n truyen tid cara cic of khic nhau co the din den sir dung kenh kern hilu qui vi din den s6 hrqng lon cic vv va ch?m g6i tin. — Mb di ding cao, yen  khi Ring mfr ring, vi sw da ding cast Min kiln mdi trnimg. Nheng thich th(rc cia mOt mong tg t6 clac plan cep duqc die bilt nhin manh den t6c dO cao. Tinh di dOng cao li mOt thich thirc cho cic thuig toin t6i uu 1#p nhim s6r dung tot ban bang thong kenh hoc sb dung cic tuyen dutmg duqc dinh nghTa tru6c de chuyen tiep thong tin. — An ninh vi nhu cis rieng hr vi cfc m6i plan tam. C6 mOt thich thirc ve can d6i gifts nhu ciu ve bio m#t vi tinh rieng tu. MOt mkit, ben nh(in mu6n dim bio ring c6 the tin liking ngu6n thong tin. Wit khic, sir tin luting d6 c6 the mau than voi cic yeu ciu rieng to cfia ben gtli. — Tien chain boa so  limb ding. C6 mOt nhu ceu cho truyin thong tieu chuin cho phep VANET lim vile qua cic kieu khic nhau vi cic chuin caa OEM. Tuy nhien, chic chin ring OEM se mu6n too ra vii sv kbic hilt v6i cling nghl VANET. Nhung raw tieu niy li c6 ye se khi kh6 khan. Mich thfrc chink ye mat klub ti xi — Phan tich vi xic dish &Nov cic lqi ich cult VANET cho an toils giao thong vi hien qua vin tii. Cho den nay, rit it vile da duqc thvc hi¢n de dinh gia tic dung c6a VANET nhu mOt ngu6n thong tin ve hinh vi lii xe. Re ring, nhung thich thirc lien quan trong vile giii quyet vin de dinh gii tic ding li m8 hinh c6a cic khia conh lien quan den yeti t6 con ngutri. — Phan tich vi xic dinh thrqc dic m6i (plan he chi phi - lqi lick adia VANET. Do thieu cic nghien ciru ye lqi ich c6a VANET, v#y plan tich chi phi - lqi ich kh6 ce the duqc thvc hiOn. Chien luqc trien khai thiet ke cho load hinh VANET li kitting dra tren mOt cc s6 141 tong hoc mOt nhtt cung cop dich vp nio. Vile thiet bj VANET ce dirge hay kh8ng con phv thuOc vio cic d6i tic truyen thong, cic hi thong mong hiln thOi c6 the h8 trq duqc hay khOng. — Nhing VANET trong kJ& trac hi thong giao thing thing minh. VANET 0 la mOt phlin cua mOt hi thong giao thong thong minh noi mi Wing yes t6 khic duqc sinh ra boi diet' khien den giao thong hay cic cic load bin tin bio 4 CHUt5NG 1. TOng quan ve he thong mpg Vanet hieu khic nhau. COng nhu vay, giao thong ci nhan vi Ong cling phii duac nim trong tii khoin trong mOt kiln cich chung. Bei vay, he thing hqp tic Nit sir cin duqc phit triin. Nhu co the thiy tfr danh sich 6 tan etc ring (twig, ky thuat vi vie khia cunh kink to xi hOi, linh Arc (mg dung xe vi cic Ong nghe lien mpg dua tren ding nghe tren mOt no lirc lien nginh trong truyin thong vi mang, thiet bj dien ter tong xe, quin vi van hinh throng b0, cling cep cic th8ng tin vi dick vv. Do de VANET ce the duqc xem nhu li mOt phin quan tong cia he thing giao th8ng dieing minh (Intelligent Transportation Systems) (ITS). Trong 'chi nhiiu du in khic nhau da thio luan chi& luqc tan lchai oho VANET, cic nghien c(ru chi yeti giii quyit nhitng thich thee ky thuat. Hien nay, mOt sir thay dii to rich dip can "ter dm% led" co dien Bing cich tap can "te tren xuong" Ly tueng nhit, ci hai phuang phip tiip can cutii ring se gap nhau• nhang gi duqc goi li mOt yeu ciu cho viec tan khai mang lui lqi ich co the duqc hi trq bOi nhing tier b0 cong nghe. 1.3. LOCH sir VA skr PHAT MIEN CUA VANET Lich sir cea viec sir dung song v8 tuyin vi hing ngoai cho truyin thong gifts xe vei xe vi xe vei ben dueng gin lien vei sir phit trim ctia 14 thing giao thong th8ng minh. Nhu them khio trong Shladover vi tong Lasky vi Ravani, cic khii niem ca ban oda tu dung Ma dueng b0 nhu viec se dung the ky thuat truyin %Ong vi dieu Ichien di giao thong duting b0 an tan, hieu qui vi than thien vei mOi truing. Sau de, vac cam' nheng am 1960, he thing tu dOng hes dating b0 dva tren song v8 tuyin duqc phit triin vi cheng minh Ki hY do, co rat nhiiu de lieu dugs quan sit: Chi di chinh li an tan, hieu qui vi than thien voi mOi trubng, tong tam lien tuc thay doi theo thin gian. Vi du, trong thei gian diu he thing hueng din tuyin dueng da duqc dieu tra. Sau do, he thing thu phi, nghien ciru lii xe tu dOng tre nen ph6 ban. Nghien ciru vi phit trier o khu vuc khic nhau, chi yiu 6 my, Nhat Bin, vi Chau Au, mi can o cic nai khic tren the giOi cing co anh huong. l>e tii de duqc dinh diu bei sir tap trong 'chic nhau cia 8 t8 vi cic cling ding giao thong van tii. MOt chi di nhit quin theo thei gian li "ngan sich - ai se tri phi?". MOt mat, nginh cong nghiep 8 to vi dien ter nghi ng6 cic ca se hu tang dog rung cho he thing dueng cao tic thong minh (Intelligent Vehicle - Highway Systems) (IVHS) se khong bao gib thich hien thuc. Mat khic, cic dan vi chi quin dueng cao tic nghi nge lieu tong nghe IVHS se cung cep giii phip thuc ti cho cic vin di dueng cao tic thqc sir. Trong phin du& day, se di cap din cic hoot dung buec tien quan tang lien quan din VANET. 5 CHISONG 1. Ting quan ve hg th6ng mane Vanet 1.3.1. TIr &iu din giea nhihog nano 1990 O My, mot ho thing hutmg din &Ong dien to (Electronic Route-Guidance System) (ERGS) d8 duqc de xuit trong Rosen: "He thing djnh hutmg diem den. Ngutri dieu khien xe nhap vito mOt mA, dal dien cho dja chi dich c0a minh vao thiit bj xe. Sau d6 khi phuang tien tien den mil diem giao ma dich duqc chuyin den atic tram ben dtrong tai de n6 duqc giai ma, theo mOt chtrong trinh ltru tat, va mOt chi din dinh tuyen duqc truyen lai cho chiec xe." He thing truyen thong sbr dung tin só 170 kHz clOng Ang-ten yang duqc lip d*t tai nut giao %Ong va gin vao phia sau caa xe. Tic dO truyin catlieu bao cao la 2000 bit/gialy. Nhung nhang n8 luc ERGS bj chim dirt do cac ca so hu tang ben duong dit tien. Tai Nh.t Ban, he thing dieu lchien giao thong 8 te tan dien (CACS) duqc thuc hien 1973-1979 do ca quan deg nghiep Khoa hac va C8ng nghe dui BO Thucmg mai va C8ng nghiep Quic ti (MITI). Muc lieu cua CACS duqc trinh bay trong Kawashima vin con hien luc sau han 30 Min: — Giant un tic giao thong dubng Xi; — Giam khi thai gay ra bbd su tic nghen giao thong; — Phong ngta tai non; — Nang cao vai fro cling ding va xa hOi cila 8 t6. Be flat duqc muc lieu nay, bin muc tieu thuat di duqc de ra: — Huang din lai xe di then cac tuyin chgmg thich hqp nhit de tranh On tic va 8 nhiim khOng khi; — Cung cep th8ng tin lieu ich de hi trq lai xe an town; — Uu tien cac xe ding cling hotic truing hap khan cep; — Cung cap thong tin kip thin cho ngutri lai trong throng hqp khin cap. Cac du an CACS ding duqc thuc hien thi diem vei 98 thin bi ben dtrong A. 330 xe tht? nghiem (Nakahara vi Yumoto). Dii vai truyen thong ben throng thi xe, cac tram ben dubng str dung Ang ten Ong con cac phucmg tien giao thong sa dung Ang-ten 101 cho tic dO truyen tai ctia bao cao la 4.8 kbps. Tai chat' Au, de an Prometheus (chuang trinh giao &Mg chAu Au vai gia cao nhit chua mang lui hien qua vi an tan) ichoi xutmg vao nom 1986 va ra mit nom 1988 c6 * nghlit kich thick host ding nghien dru va phat tan trong rah vuc deg nghe th6ng tin va twin th8ng di dung cho xe c6 ding ca va nhang con duOng. Prometheus di drat hi trq boi 19 quic gia chau Au vb. cac Oy ban cling ding Chau 6 CHYONG 1. Ten quan ye he thOng mpg Vanet Au (Walker nam 1992; Williams 1988). Nhu vi du neu trong Gillan, Prometheus di duqc t6 chi= tai cac he thong khhc nhau, bao g6m: — PRO-CAR: lai xe trq bb i he thong dien tb; — PRO-NET: truyen thong gitta xe yeti xe; — PRO-ROAD: truyen thong gifts xe va m8i trutmg. Trong Prometheus, truyin th8ng gitta xe va xe (long met vai Ire n6i b#1: bao cao cat' Dabbous va Huitema vin c6 the duqc chu Sr cep nh#t trong nhieu khia canh. Dabbous va Huitema phan Lich cac yeu ciu truyen thong Ara tren ldch ban dien hhih, vi du cho chin ttp that' &Si lin &Ong. Gii sfr mOt chain luqc quing ba dinh kjr va you ciu dO chinh xAc khoing cach va chum, ho chi ra ring met danh gin th#n tong t6c de truyin ban tin tang thai cda mii xe se djnh ki gfri 20 phien truyen tren mil giay ciut m6i Dabbous va Huitema cang cho thiy cac neu gam di you clu ve de chink xlic khoang cach va chum va gioi thieu cac phuang phap du dam 05 the lam Ohm ding ke s6 lin you ceu truyen tai. DA duqc tip trung tren clic he thong hog ding 6 bang tin 60 GHz. Su quan tam trong truyin thong gifts xe v6i xe tilp top 6 Nh#t Bin va my. cuoc khao sit trong Kawashima trich din hai bin bio cao thu#t cis JSK hiep hOi cling nghe dien tfr cho lai xe va 8 to (Association of Electronic Technology for Automobile Traffic and Driving) duqc xuit ban Nilo nam 1986 va 1988, Wong Ong, lc& qua thil nghiem truyen th8ng gitta xe vai xe. 6 My, nhu duqc nett trong Shladover, mOt trinh dieu khien chinh xuit hien de to ding lai xe va nhieu phuong den. Trong Sachs va Varaiya, cac you cau va thong se ky thuit de truyin th8ng giita xe v6i xe vi gitta xe yeti thiet bi ben diking de cho xe to gong duqc trinh biy. Tong kit du in hoot gag cha thtri ki nay tai My, Chau Au, va NIgit Ban cling nhu nhin ve twang lai doi vai he thong throng truyen cao tec th8ng minh (Intelligent Vehicle-Highway Systems) &gm dua ra beri Jurgen. 1.3.2. Tw min nhang nans 1990 din nay Nth sau cha nhiang nam 1990 la cet mec quan tong ghi lai met su thay doi 16n. Kit qua An ttrong ye trinh dieu khien hqp tic dOc 1#p duqc chimg minh tai San Diego, bin gioi thieu cOa cac dei tac California cho nang cao vfn tIi va doting cao tec (Advanced Transit and Highways) (PATH) vho nam 1997, giai dap 2 giai thieu ye nang cao tinh an town phucmg den (Advanced Safety Vehicle) (ASV) vho Mtn 2000 tai thanh phi Tsukuba, Nh#t Bin, va trong du in PROMOTE CHAUFFEUR European. TOp trung sau de chuyen tfr lai xe kit hop to quan sang he thong trq trinh dieu khien hqp tic. Ti My cac sang kill phucmg tien thong minh (Intelligent Vehicle Initiative) (NI) trong nhiang atm 1998-2005 (Hartman va Strasser ) t#p trung vao an tohn hieu qui hqp tac. Tai chau Au, cac du in CarTalk vi FleetNet cba Franz nghien 7 CHUONG 1. Tong quan ye he thong mong Vanet ciru ding nghe va cac (mg dung he trq hqp tic Idi xe. T31 NhUt Ban, giai don 3 caa dg an tiring cep an tan phuang lien cling th6a then vai tr6 cult truyin thong lien phucmg tien de he trq hqp tic lai xe. Sq thay del tin 96: 5.9 GHz DSRC IChai niem ve VANET di bi inh huong bei nhtIng lien b0 trong Ong nghe va tieu chuitt hea ke tfr gitta nhting nam 1990. Nim 1999 la mOt "sir thay dei tan se" xay ra khi 1:Jy ban Truyin thong lien bang my phis be bang thong 75 MHz cua did 5,9 GHz cho truyin thong tam ngin chuyen dung (Dedicated Short-Range Communication) (DSRC).Thuet net truyin th8ng tam ngin chuyen dung (Dedicated Short-Range Communication) di duqc sir dung nhu mOt tht4t net tuang 14p ve Ong nghe cho =yen thong khong day tam ngin gifts cac xe va ca s8 ho ting. MOt rim sau, ASTM International thinh lep met nh6m lam viec de ghat trien cac yeu caw ve tieu chum DSRC tuang (mg. Trong nim 2001, Uy ban tieu chuin 17.51 cut ASTM chcm IEEE 802.11a la c8ng nghe v8 tuyen nen tang cho DSRC. Cac lieu chitin Wang ting di duqc dua ra trong nam 2002 vi sM di vac nam 2003 (ASTM E2213-03 2003). Cac ap lqc phai sir dung kenh duqc giao va tinh kha thi ¢ua cac deg nghe Ara chuin IEEE 802.11a thi lam tang ding ke cac hoot dung nghien cuu va phat tan. DUc biet, cling deng mong di dOng quan tam den chili de caa ming luoi xe di duqc hei sink. Nim 2004, IEEE bit ttiu deg viec stla 661802.11p va tieu chuin truy cUp lchong day trong m8i tramg xe CO (Wireless Access in Vehicular Environments) (WAVE) dqa tren cac lieu chitin ASTM (Jiang va Delgrossi). Dir an truyin thong an town phucmg On (Vehicle Safety Communications) (VSC) duqc he trq ben to ch(rc do luting an town va ch?m (Crash Avoidance Metrics Partnership) (CAMP), cuc quan trj duting cao tec lien bang My (US Federal Highway Administration) (FHWA), va ban quart ly an town giao th8ng dtrong bO My (US National Highway D•ajjic Safety Administration) (NHTSA) khao sat ccIng nghe DSRC 5.9 GHz dang n6i trong nhUng nam 2002 den flint 2004 va ket luin ring phuang phalp dip clura tren chuin IFFF, 802.11a se c6 the M trq hiu hit cac (mg dung an town ma VSC di chcm. Cac bao cao cu6i cling mkt VSC (VSC 2006), cOng dun ra met ckh rO rang nhttng thach &tic cna truyen th8ng c6 dO trg thep vi if& sin sing cao colt cac kenh vo tuyen cling nhu cac yin de lien quan den Icha fling caa kenh nei chung. Nam 2004, HOi thao qu6c to ACM diu lien ve mong xe CO bit djnh (Vehicular Ad Hoc Networks) di din ra Philadelphia, sau de thuUt net "VANET" di duqc det ra. Cac dy in Mtn tai vi host dung Trong phin nay, di cep mOt cai nhin teng quan kh8ng day du ye cac dir an VANET dang dign ra va cac hoot dung 6 chau Au, Nht Ban, va Hoa Ky. Met cal nhin 8 CHISONG 1. 'fling quan ve he thong mung Vanet t6ng quan cho they mirc dO hoot dung cao trong linh vvc nghien cuu vi phit tan VANET vi de chirng minh li cic deg nghe truyin thong khong day duqc bio dim li ca so cua lieu het cic hout Ong cila VANET tren toin the gioi (hinh 1.2). Trong chuang trinh khung se 6 cua EU, ben dv in duqc bit dau trong cic linh Arc ce lien quan den VANET: COOPERS, CVIS, PReVENT, vi SAFESPOT. Dv in he thong hqp tic cho an toil) duOng b0 th8ng minh (Intelligent Road Safety) (COOPERS, 2006-10) t#p trung vio img dung vin thong tien tier cho quin hqp tic giao th8ng. Tir gee go truyin thong, th8ng tin ch6 yeu lit truyin thong gitta xe vi cic from ben throng vi s>3r dung lieu chain CALM nhu giao dien truyin thong hung ngoui CALM. CALM li ISO TC 204 (ITS) Working Group 16 (Communication) trong "giao dien kheong day lien tic cho khoing cich tittnmg binh den". CALM nham muc dich trq truyin th8ng lien tic cho xe bang cich sfr dung cic phuang tien truyen thong khic nhau vi cic giao dien truyen th8ng. Cic dv in he thong co ser hit tang phuang tien hqp tic (Cooperative Vehicle-Infrastructure Systems) (CVIS, 2006-10) di tip trung vio phit trier vi th(r nghiem trivet' thOng cfia phuang tien vol ca s8 hu tang vi theo lieu chat' CALM. CVIS lam cho vies sir dung WAVE WEE 802.11 c6 lien quan giao dien duqc hieu lii giao dien M5 (d6i voi "Microwave 5 GHz) trong khuen kh6 CALM. Dv in SAFESPOT (2006-10) nhim muc dich thiet ke hu thong hqp tic xi cho an tan &gong bto dva truyen th8ng gitta xe Wei xe vi xe vOi ca sO hu tang. Cic deg nghe truyin th8ng duqc s>Sr dung trong dv an SAFESPOT li IEEE 802.11a/p. Dv in PReVENT (2006-08) giii guy& phit tan cic Ong dung an toin dv plitong vi c8ng nghe trong dv an PReVENT tick hqp, cic dv in nho WILLWARN (Wireless Local Danger Warning) t#p tning vio cic cho de call truyin th8ng gift xe v6ri xe vi gitta xe yeti ca so hu tang. He thong WILLWARN dva tren IEEE 802.11a/p vi di sir dung nen tang truyin thong phit trien b Dirc do; in Network on Wheels (NOW). Ngoii ra, dv in Secure Vehicular Communication (SeVeCom, 2006 din nem 2008) di duqc dinh rieng de xic djnh cic mei de do vi quy djnh cu the phuang phip vi Icien trac de dam bio truyen thong xe Icheng day. 9 CHIANG 1. Toting quan ve 4 thOng mpg Vanet Hinh 1.2 MS hinh tong quan 4 cdc gitii phdp VANET Hien nay, theo chucmg trinh 7 khung, huang ten cac thtl nghiem rinh voc duqc tai trqi, dac biet 11 do in PRE-DRIVE-C2X dang chitin 1)1 xay dung cac kh8i an that cho thir nghiem thimh c8ng hoot dung cua VANET a chAu Au. TO Nhat Bin, mOt tieu chwin a xe ca tilt truyin thong voi co at ha tang da duqc c8ng biS Mtn 2001 vi goi la "Dedicated Short-Range Communication System" (ARIB 001). He thong hoot dung 0 an s6 5,8 GHz, duqc doa tren da truy nhap phin chia theo thbi gian (TDMA) vi trong phom vi 30m. Moc Bich chinh cua he thOng la stt cb,mg trong vier thu phi dies fil nhtmg da duqc tan khai de h8 trq cho cac dich vo 'chic (ARIB 2004). Trong nam 2008, tren 20 trieu don vi bo mach din ter da duqc trian khai. Ti Nhat Bin, dim tren so thanh c8ng tren he thteg DSRC 5.8 GHz vi truyan thong tren cac xe dtra tren ha tin hang ngooi, nhiau do an vi clic hoot Ong ITS hien 10 CHUONG 1. Tang quan ve he thong mong Vanet dang tham gia de chimg minh %/a tang cuing phuang tier, cot sa ha ting va truyen thong xe vii xe duai sang hen an town ITS 2010 Oa NI* Bin. An town xe nang cao sang kien, trong giai down 4, dang giai quyet xe, truyen th8ng xe bang each tray c#p vao mOt met he thong da nhiem (CSMA) dim tren phin ma ring eta ARIB STD T-75. Cruise - ha trq sang kit!' he thong duang cao t6c duqc xay dung tren he thong 5.8 GHz DSRC cling nhu he thong hi trq lei xe an town (DSSS) cling sir dung cOng nghe hang ngooi truyen thong cho xe ben 11 throng. Cac hoot ding Smartway tap Ming vao cac djch vu ITS va mOt nen tang djch vu thong thuang duqc cung cip tren diu trang cat' cac mang hi& hien ca. Trong thing 6 am 2007, n6 di duqc deg b6 kenh 10 MHz trong cac kenh tin s6 700 MHz se duqc phan b6 cho truyen thong lien quan den an tan lien xe toi NI* Ban vim am 2012. CO mOt s6 do an deg nghiep chinh phi 6 MI duqc thrc hien vi duqc (Lang tren bao. Hai trong s6 nhung do an de duqc m8 tit 6 duai day. Lin diu tien Vehicle Infrastructure Integration (VII) duqc di ten thanh IntelliDrive, gin day met y tuang Ian dit duqc ch(rng minh. Thir hai la do an ang dung truyen thong an town phuang tien do kien se duqc kit thic vao cu6i am 2009. Ca hai du an tren d u qc sv tai trq ctla 130 giao thong Hoa KI vi mOt s6 nha san xuit 8 to va nhi cung cep. Ngoii ra, hai do an khitc xirng clang duqc a Op ngin  mOt chr an dang din ra he thong an tan duqc tich hqp tren phuang lien lcham phi cac vim de giao dien ngutri-may vi mOt s6 img dung an town, vii khuyen cao ce khi Wing chang cheo hoc miu thuin, duqc xiy ra ding thai (Doi hoc giao thong vin di Michigan). Dv an tha hai li Cooperative Intersection Collision Avoidance Systemproject gam co ba thanh phin (McHale). Dv an canh bao vi phom 6 Michigan, do an Stop Sign Assist 6 Minnesota vi do an Signalized Left Turn Assist 6 California. Kid xe duqc trang bj CICAS-V den gin mOt ngit tu, cac phuang tien nhon duqc tin hieu vi *Ong tin thai gian tit tin hieu den giao nhau (DSRC). MoSi chi& xe sau da se do down kha Wing ring n6 dang 6 NI tri c6 den do, vi neu thich hqp, cash bao trinh dieu Ichien (Maile). Dv an nay di duqc len Ice hooch dill nghiem vii trinh diet' khien don gian (Maile). 1.3.3. Kit qua can ak dr tin hifn tqi a. TYch kw co sd• hg ling (Vehicle Infrastructure Integration) Trong ram 2005 130 giao thong van tai Hoa KI bit din di* nghiem met Meng mai. Da s6 cac m8i twang that nghiem nay duqc thtrc hien 6 cac yang ngooi 8 phia tay bic cia Detroit, MI. He thong bao gam 55 tram thiet bj trong yang 116.55km2 vi si dung 27 chi& xe. C6 bay ung dung duqc phat Wen vi tha nghiem: 11 [...]... truyin th8ng tin ca di khemg lam mit th8ng tin Trong Fujilci gift djnh ring th8ng tin v6 cac yang lan can Wit mOt chic xe duqc yeu ciu thubng xuyen hcm thong tin ve mOt khu Arc xa x6i VI thi, btu ich di truyin tai cac de lieu thubng xuyen hon Adler di nghj tinh toga lqi ich town ciu (ctla mOt ban tin duqc gtlti Quyin lqi nay duqc s>Sr dung di them s6 quy trinh truy c(Ip trimg binh MOt ban tin thich hqp... ciru dva vao ki thu#t "phat tan tin din" (rumor spreading), "buen chuyen" (gossip), hoc "clich benh" (epidmice) day, met nut nIgin thong tin thi se luu lai ban tin hien thbi vat diy ne cho cac nit khac.Tuy nhien, nheng Icy thu#1 nay yen sir dung mOt catch dip c4 ► giting nhu trim Iv De hp chk s6 knyng tin nhin duqc truyen, cac nut sat quyet djnh chi phi bien cgc thong tin mai nhit Ngoai ra, co the co... c6 the huang lqi te ban tin Thong tin se duqc quang ba met lin nita Catch tiep con nay ci the duqc thea huemg cac thong tin b6 sung trong ban tin de de ding quyet djnh ma tren db cac nut duqc quan tam trong cac dl lieu Trong Ducourthial trinh bay mOt catch tiep On them dja chi dja ly vao ban tin de tao dieu kien thu#n lqi cho cac nit nh#n ci the phan tich Bing catch danh gib tinh tang sau di ci the... ky Nhting bim tin duqc ph6 bien va duqc gift trong mOt khu vuc XaC djnh truoc Neu mOt nut bit ld quan tam den tin nhin ce the Ming ky vao su !den nay clang kiem tra xem tai dja phucmg Neu met ban tin duqc nhOn bOi nut ma ne ce the dieu nay phi hqp yin ding Icjf ciut minh hay khong Thong tin duqc nhan d8i va nhCmg bim sao nay duqc truyin den mOt s6 nut trong khu vtrc Neu met nut rid kit& thong tin khu... cac RSU dec lip hotic kit nai cung cap thong tin lien 1pc di ding horn gitta cic nhom xe Ttai day, ca ban cic diem iruy cep RSU thrqc d#t ben dubng, cang them gia trong giao thirc phan Whom 2.3.2 Truyin tdi tisOng tin Trong khi thin Min lam the nio de vin chuyin th8ng tin trong mpg, nhieu nghien cfru citing xem xth truyen mOt phin cha thOng tin ho#c bin tin Mire dO pha hqp chirc Wing sir dung so skill... c6a cac bin tin sin ch Co the stir dung tu6i vi khoang cach den mOt ngu6n tai nguyen cho cic chrrc Hang phi hqp, hotic phin lopi cac tin nhin nhin (taw theo teem quan trong cfia no KM truyen tii kiln thirc dja phuang din cic xe khic, mOt ban tin day la cho din khi Idich thu6c goi tin dot tai da Dieu nay se giap cic kich thy& ban tin 6 mOt mirc dO c6 ajnh vi tranh 28 11-1/UUNt-tl Inwen tnong tin trong... ra met cai nhin t6ng quan ve tinh hinh quanh khu vvc de Tuy nhien, Icheng chi chi& xe c6 duqc thong tin nay mai can de lieu nay, ma con cac phuong den khic ding can thong tin nay de c6 the thich img vai nheng hanh vi cite ne Vi the, vies truyen thong tin cho nhitng chi& xe quan tam den thong tin de 11 rat quan tong Trong phim dub i se giii quyet van de ve truyin thong tin vai nheng phuang phap Ichic... han thi ban tin duqc 10p di 1#p lai obi rit nhieu nut Bing catch ling nghe, 157 Wong nhit la tit ca hoc gin nhu tit ca cac nit gin v6i he thing quang IA 0 duqc thong bio Vai khoang catch ngly cang tang thi tin s6 ctla quimg ba earn Hoc ce the sir dung tran lut b xung quanh nguOn mkt ban tin Dieu nay cho phep cac xe b gin han ci the truyen thong tin nhanh nhit ma kh8ng phai bin lut ban tin nao vao khu... MOt vi d i khic, he thing do xe eng dung VANET: nhttng thong tin phan loci ve tinh hlnh xe trong toitn thanh phi Thong tin duqc thu th#p lien kit va chia se trong mOt yang rung Ion nhu mong luoi dueng cao tic hoc la mong lueri throng bei thanh phi Th8ng tin c6 the la m#t dO km lugng va theri gian di chuyen, cac nai xe man phi va cac thong tin khac cif, the nhitng ngueri tham gia mpg khac theo dOi, va... thich fin met de tY le chi c6 mOt vii xe se tiep tvc quimg bit cac thong tin mai duqc tao ra KM ban tin chuyen tiep lan len din den ttm si quang ba giam De tranh nheng vin de bao quang bit ci the km chi nhitng ban tin ding thtri MOt de an khac de han the tran lit ctla dieing tin IA de cho ben nh#n quyet djnh ci nen quang ba lai cac ban tin b tit ca cac nut Vi du trong Chisalita vat Shahmehri xem xet met . CHUONG 1. Ting quan ve r ha th6ng mang Vanet CHU • ONG 1. TONG QUAN Vt HE THONG MANG VANET 1.1. GIO1 THIEU CHUNG Vt MANG VANET 1.1.1. Khdi niflm VANET (VEHICULAR AD-HOC. thong tin lin nhau. ThOng tin ye traffic, ye tinh trang kit xe, thong tin ye tai not giao thong, nguy hiem can trinh M0 chile xe ding c6 the trb thinh mOt Relay Node a chuyen tii th8ng tin. 1.1 - 11) UM,' 2. t ruyen tnong tin trong mong v anet CHUONG 2. TRUYEN THONG TIN THONG VANET 2.1. GIOI THIEU Cac img dung an total VANET yeu ciu thong tin chi tir nhung vimg giai hon dja