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Mng Cm Bin Khng Dy

1.TNG QUAN MNG CM BIN KHNG DY.31.1 Gii thiu:31.1.1 C 4 thnh phn c bn to nn 1 mng cm bin:31.1.2 Hiu qu s dng cng sut ca WSN da trn 3 yu t:31.1.3 Mt vi c im ca mng cm bin:31.2 Tng quan k thut41.2.2 K thut truyn v tuyn:41.2.3 Phn mm ng dng:42. K THUT MNG CM BIN KHNG DY.42.1 Node.42.2 Phn cng v phn mm:52.2.1 Phn cng:52.3 Phn loi theo m hnh phn b:62.3.1 Category 1 WSN (C1WSN).62.3.2 Category 2 WSN (C2WSN)62.4 Mi trng hot ng ca WSNs.72.5 Cng ngh hin nay:73. GIAO THC IU KHIN TRUY CP TRONG WSNs.83.1 M hnh giao thc cho WSNs.83.2 Cc giao thc MAC cho mng WSNs.94. NH TUYN.94.1 Vn nh tuyn.94.1.1 S phn phi v tp hp d liu.94.1.2 Thit k v thch thc trong nh tuyn.104.1.2.1 Kch thc mng v c tnh thay i theo thi gian.104.1.2.2 Ti nguyn hn ch.104.2 Cc giao thc nh tuyn.104.2.1 Cc gii thut nh tuyn cho mng.104.2.2 nh tuyn theo v tr.114.2.2.1 Nguyn l:114.2.2.2 u im v nhc im.125. GIAO VN:135.1 Yu cu thit k trong giao vn.135.2 Cc giao thc iu khin giao vn.135.2.1 Cc giao thc iu khin giao vn ang dng.135.2.3 Khi phc gi b mt.146. QUN L MNG WSNs.156.1 Yu cu qun l mng v cc kiu qun l truyn thng.156.1.1 Yu cu qun l mng.156.1.2 Cc kiu qun l truyn thng.156.2 Vn thit k qun l mng.167. NG DNG.177.1 ng dng trong qun s v an ninh quc gia:177.2 ng dng trong bo v mi trng.177.3 ng dng trong thng mi187.4 ng dng trong y hc.18

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1.TNG QUANG MNG CM BIN KHNG DY.

1.1 Gii thiu:Mng cm bin khng dy (Wireless Sensor Network) l s kt hp cc kh nng cm bin, x l thng tin v cc thnh phn lien lc to kh nng quan st, phn tch v phn ng li vi cc s kin,hin tng xy ra trong mi trng c th no .

Hnh 1 : M hnh mng cm bin khng dy.1.1.1 C 4 thnh phn c bn to nn 1 mng cm bin:- Cc cm bin c phn b theo m hnh tp trung hay phn b ri.- Mng li lin kt gia cc cm bin (c dy hoc v tuyn).- im trung tm tp hp d liu .- B phn x l d liu trung tm.1.1.2 Hiu qu s dng cng sut ca WSN da trn 3 yu t:- Chu k hot ng ngn.- X l tn hiu ni b ti cc node gim thi gian truyn.- M hnh dng multihop lm gim chiu di ng truyn .1.1.3 Mt vi c im ca mng cm bin:- Cc node phn b dy c.- Cc node d hng.- Giao thc mng thay i thng xuyn.- Node b gii hn v kh nng tnh ton,cng sut, b nh.- Khng c thng nht ton h thng v s lng node nhiu.1.2 Tng quan k thut1.2.1 Cm bin:- Chc nng c bn.- X l tn hiu.- Nn v pht hin,sa li.- Phn chia Cluster.- T phn nhm.1.2.2 K thut truyn v tuyn:- Dy truyn sng.- S h hi ng truyn.- K thut iu ch.- Giao thc mng.1.2.3 Phn mm ng dng:- H iu hnh.- Phn mm mng.- Phn mm kt ni c s d liu trc tip.- Phn mm middleware.- Phn mm qun l d liu.

2. K THUT MNG CM BIN KHNG DY.2.1 Node.

Hnh 2: Cc thnh phn trong mt Node.Cc thnh phn cu to nn mt Node :- Mt cm bin (1 hay mt dy cm bin).- n v x l.- n v lin lc bng v tuyn.- Ngun cung cp.- Cc phn ng dng khc.Cc node c kh nng lin lc v tuyn vi cc node ln cn v cc chc nng c bn nh x l tn hiu, qun l giao thc mng v bt tay vi cc node ln cn truyn d liu ti trung tm.

Hnh 3: S pht trin cng ngh ch to cm bin.2.2 Phn cng v phn mm:2.2.1 Phn cng:- Ngun cung cp.- Lu tr v tnh ton.- Cm bin.- Lin lc.2.2.2 Phn mm:- H iu hnh.- WSN Sensor Driver.- B x l thng tin.- B x l d liu.

Hnh 4: Phn cng v phn mn node

2.3 Phn loi theo m hnh phn b:2.3.1 Category 1 WSN (C1WSN).- H thng li kt ni a ng gia cc node qua knh truyn v tuyn s dng giao thc nhtuyn ng,cc node tm ng i tt nht n ch .- Vai tr ca cc node nh cc trm lp vi khong cch rt ln.- X l d liu cc node chuyn tip. Mng phc tp.2.3.2 Category 2 WSN (C2WSN)- M hnh im-im hay a im-im, ch yu l cc lin kt n gia cc node (single hop),dng giao thc nh tuyn tnh.- Mt node khng cung cp thng tin cho cc node khc.- Node chuyn tip khng c kh nng x l d liu cho node khc.- Khong cch vi trm mt. Mng n gin.

Hnh 5: M hnh mng.2.4 Mi trng hot ng ca WSNs.Node cm bin b rng buc bi mt s yu t:- Ngun cung cp: Cc node b gii hn bi nng lng cung cp.- Lin lc: Gii hn v bng thng, nhiu knh truyn, nh hng n tin cy, cht lng dchv v bo mt ca h thng.- Tnh ton: Cc node c cng sut tnh ton v b nh gii hn, nh hng n vic la chngii thut x l d liu.2.5 Cng ngh hin nay:- Kch thc, gi thnh v cng sut tiu th ca node gim, s thng minh ca node phi tng ln.h thng cm bin kt hp cc k thut tin tin nh cng ngh nano, mng phn b, thng tin vtuyn bng rng- Vic tiu chun ha cng rt quan trng. To ra cc tiu chun chung s gip mng WSNs ngdng rng ri hn trong thc t, c kh nng giao tip vi cc mng khc, giao din Internet,cung cp cc dch v a dng hn. Cc nghin cu ang hng n cc k thut ch to cmbin mi, h thng mng cm bin phn b, tch hp cm bin trong cc h thng thng mi, htr hiu qu cho cc qu trnh ra quy t nh.

3. GIAO THC IU KHIN TRUY CP TRONG WSNs.Mng khng dy da trn truyn sng in t qua mi trng khng kh, tun theo cc c tnhtruyn sng nn vic i x vi cc node trong mng phi nh nhau, t c iu ny vic s dnggiao thc iu khin truy nhp mi trng MAC (Medium Access Control) l cn thit.3.1 M hnh giao thc cho WSNs.Xut pht t m hnh OSI, giao thc MAC c xy dng lp thp ca lp lin kt d liu (DataLink Layer_DDL). Lp cao ca DDL c xem nh lp iu khin logic (LLC).Lp MAC nm ngay trn lp vt l v n cung cp cc chc nng sau:- Kt hp d liu vo frame gi .- Tch frame thu c ly thng tin kim tra li khi phc lai thng ip.

Hnh 6: M hnh tham kho OSI v cu trc lin kt lp d liu.Lp LLC ca DDL cung cp giao din trc tip cho lp cao hn nhm mc ch ngn cch lp caovi cc lp thp hn pha di3.2 Cc giao thc MAC cho mng WSNs.- Schedule-Based Protocols: giao thc to ra s sp t trc iu tit truy cp ti nguyn trnhxung t gia cc node, thng thng cc ti nguyn l thi gian, bng tn- Random Access-Based Protocols: giao thc truy cp ngu nhin da trn s tranh chp, khng ihi s phi hp gia cc node ang truy cp knh truyn. Cc node ng ngng mt khongthi gian trc khi th truy cp tr li knh truyn.4. NH TUYN.4.1 Vn nh tuyn.4.1.1 S phn phi v tp hp d liu. thc hin vic trao i thng tin t cc node n base station th phi c mt ng kt ni trc tip tuy nhin vi kt ni ny th s suy gim nng lng mt cch nhanh chng. Do lm hn ch kh nng bao ph rng ca mng. Do gii quyt nhc im ny th d liu trao i gia cc node cm bin v cc trm c truyn a chng(Multihop). Cc lin kt ny c th ko di khong cch v to ra mt ng linh hot. Phng php ny lm gi m ng k can nhiu gia cc node ang tranh chp truy cp knh truyn c bit l trong WSN mt cao.

Hnh 7: M hnh nh tuyn.Trong Multihop cc node trung gian phi tham gia vo vic truyn ti cc gi d liu gia ngun v ch. Xc nh node trung chuyn l vn ln trong gii thut inh tuyn bo m s chnh xc tnh n nh v kh nng ti u.4.1.2 Thit k v thch thc trong nh tuyn.4.1.2.1 Kch thc mng v c tnh thay i theo thi gian.Cc node cm bin hot ng vi kh nng tnh ton, lu tru v thng tin hn ch do gii hn ngun nng lng cung cp, mt cm bin cng c th rt it hoc dy c. Trong mang WSNs cc node trng thi ng v kh nng thch ng cao do yu cu t phn b v tit kim nng lng. Cc node phi t iu chnh hot ng p ng vi s tht thng khng th on trc ca cc kt ni khng dy.4.1.2.2 Ti nguyn hn ch.Vn ngun nng lng cung cp cho s lng node ca mng hot ng.Kh nng thit k mt gii thut nh tuyn thng minh cho mng hot ng vi hiu qu cao nht ang l vn ln.4.2 Cc giao thc nh tuyn.4.2.1 Cc gii thut nh tuyn cho mng.- Proactive(khi to trc): da trn s phn pht theo chu k thng tin t c bn nh tuyn nht qun v chnh xc n tt c cc node ca mng. Cu trc mng c th bng phng hay phn cp. Trong phng php ny cu trc phng th tm ng i ti u hn.- Reactive(phn ng): xy dng tuyn n mt ch no theo nhu cu. Gii thut ny thng khng chuyn ti thng tin qua tt c cc node ca mng. Do chng da trn nh tuyn ng tm ra ng i.- Hybrid(hn hp): da trn cu trc mng to nn tnh n nh v kh nng m rng cho cc mng c kch thc ln. Gii thut ny chia mng ra thnh cc cluster, do s lng ln v tnh di ng khi cc node vo hay ra khi cc cluster. Gii thut ny kt hp Proactive trong cc cluster v Reactive cho s lin kt cc cluster.Cc k thut nh tuyn:- Dng 1: giao thc dnh cho mng c kin trc phng ti thiu cho overhead xy dng cho htng mng v c kh nng tm ra nhiu ng lin lc gia cc node vi sai s cho php.- Dang 2: dng trong mng c cu trc tit kim nng lng, n nh v kh nng m rng. Cc node mng c sp xp vo cc cluster trong mt node mng ln nht c vai tr nh mt cluster head. Cluster head c vai tr phi hp hot ng ca cc node trong cluster v chuyn thng tin gia cc cluster. Vic phn hoch gim nng lng tiu th v ko di thi gian sng ca mng.- Dng 3: dng phng php data-centric phn b yu cu trong mng. Phn nhim v cho cc node v nh r mt thuc tnh ring bit cho cc node. Kiu thng tin c th dng nhBroastcasting, anycasting, Geo-casting..- Dng 4: dng v tr ch ra mt node cm bin. nh tuyn da trn v tr rt hu ch cho cc ng dng m v tr ca node trong vng a l c th c hi bi node ngun. Yu cu nh th c th nh r vng no m cc hin tng quan tm c th xy ra hay ln cn vi im c bit no trong vng hot ng ca mng.4.2.2 nh tuyn theo v tr.4.2.2.1 Nguyn l:Dng thng tin v v tr tm ra tuyn lin lc hiu qu t ngun n ch. Khi cc node s gi vai tr chuyn tip gi(forwarding), do n phi hiu bit v cu hnh ton mng.- Forwarding: Most-forward-within-R(MFR): chn node nm xa nht trong s cc node nm trong vng ph R Nearest-forward-progress(NFP):chn node gn nht. node NFP c chn nhn d liu t node MH. y l node gn nht tnh t MH Compass routing chn node c gc nh nht to bi ng thng ni MH ti node c chn theo CMP c chn. Low energy forward chn node ti thiu nng lng c yu cu, node LEF c chn chuyn.

Hnh 8: M hnh chn node truyn theo nng lng.- Gii thut khng ti u:ng i ti u t S1 n D l ng ni trc tip t S1 n D.

Hnh 9: Gii thut nh tuyn khng hiu qu.

- Gii thut ti u: Right-hand: mt gi xut pht t node Ni mun truyn n gi Nj, xung quanh c nhiu node ln cn th tuyn truyn c chn k tip l tuyn truyn u tin theo quy tc ngc chiu kim ng h tnh t ng thng ni NiNj. Tuy nhin gin ny gp phi trng hp khi tuyn ct ngang ng thng ni ngun v ch. face traversal: gii thut trnh cc ng ct ngang, nn tuyn c chn k tip theo quy tc Right-hand giao vi ng thng NiNj

Hnh 10: Ci thin cht lng giao thc nh tuyn.4.2.2.2 u nhc.- u: nh tuyn theo v tr ph hp cho mng WSN v yu cu t thng tin cho iu khin v tng tc cc b gia cc node.- Nhc: cc lin kt bt i xng v cc ng giao nhau lm tng phc tp ca giao thc.5. GIAO VN:5.1 Yu cu thit k trong giao vn.Mng WSN c thit k vi cc tiu ch bo tn nng lng, iu khin tc nghn, tin cy trong phn phi d liu, an ninh v qun l. Hai