Vyog muajLightCkev paub
Lub teeb pom kev sib txuas lus (VLC) tsis tsuas yog ua tau raws li qhov xav tau ntawm cov teeb pom kev zoo sab hauv, tab sis kuj muaj kev sib txuas lus wireless. Nws qhov zoo xws li tsis muaj xov tooj cua zaus hluav taws xob hluav taws xob hluav taws xob, tsis tas yuav muaj kev lees paub qhov tseeb ntawm spectrum, tus nqi qis, tsis pub leej twg paub, siab modulation bandwidth, thiab high-speed kis tau tus mob tau txhawb txoj kev loj hlob sai ntawm cov tshuab no.
Classification ntawm Wireless Communication Technologies
Wireless access technologies feem ntau suav nrog Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), thiab Time Division Multiple Access (TDMA). Txawm hais tias FDMA thev naus laus zis tuaj yeem muab cov bandwidth loj tas li, nws yuav tsum tau xa thiab txais cov khoom siv kho qhov muag los lim cov teeb pom kev sib txawv ntawm cov wavelengths sib txawv, uas ua rau cov khoom siv tsis yooj yim thiab tsis yooj yim rau kev hloov kho, yog li txwv tus naj npawb ntawm cov nkag nkag; CDMA thev naus laus zis xav kom lub teeb liab cov cab kuj muaj cov ntsiab lus nplua nuj nyob rau theem, thaum lub VLC system hauv kab lus no siv qhib qhov tseem ceeb tswj (OOK) kev hloov kho thev naus laus zis, uas tsis muaj qhov hloov pauv txaus kom tau raws li CDMA cov cai. Yog li ntawd, siv TDMA raws li cov kev daws teeb meem rau ntau tus neeg siv nkag tau tso cai rau kev hloov pauv hloov pauv ntawm cov neeg siv cov lej nkag. Hauv txoj kev xav, cov thev naus laus zis no tuaj yeem txhawb nqa ntau tus neeg siv los ntawm kev kho cov ntaub ntawv dhau los thiab kev ua haujlwm latency, thiab tuaj yeem hloov kho cov ntaub ntawv tus nqi rau txhua tus neeg siv raws li xav tau.
Sab Hauv Tsev VLC Network Raws li TDMA
Rau sab hauv tsev siv cov xwm txheej, los ntawm kev tsim cov teeb pom kev zoo thiab lub zog tsim nyog, kev sib txuas lus thiab kev ua haujlwm tuaj yeem ua tiav thaum ua kom ntseeg tau cov teeb pom kev zoo. Tsis tas li ntawd, nws yog ib qho tsim nyog los tsim VLC network kev koom ua ke nrog Is Taws Nem thaum xav txog tus nqi, engineering nyuaj thiab lwm yam. TDMA raws li hauv tsev VLC network uas txhawb kev nkag tau yooj yim thiab kev faib cov peev txheej rau ntau tus neeg siv xov tooj ntawm tes, ua kom muaj kev faib tawm ntawm cov peev txheej txwv tsis pub muaj nyob hauv VLC network thiab txhim kho kev siv peev txheej.
TDMA raws li pom lub teeb pom kev nkag mus rau hauv lub network thiab kev saib xyuas lub network
Rau sab hauv VLC, TDMA mechanism tuaj yeem siv los tsim qhov pom lub teeb pom kev sib txuas thiab kev saib xyuas network, piav qhia txog cov ncauj lus kom ntxaws txog kev sib tw thiab kev saib xyuas network, thiab txheeb xyuas qhov tshwm sim ntawm txoj kev no. Qhov tshwm sim ntawm 5 lub davhlau ya nyob twg nkag mus rau hauv lub network hauv txhua lub sijhawm yog 0.15625, theoretically, 7 lub sijhawm slots tuaj yeem ua kom ib lub davhlau ya nyob twg nkag mus rau lub network. Hauv kev sim, 10 lub sij hawm slots tau tsim los xyuas kom meej lub sijhawm nkag mus rau lub network ntawm ib lub davhlau ya nyob twg, yog li lub sijhawm xav tau rau tag nrho 5 lub davhlau ya nyob twg nkag mus rau lub network yog 25ms. Los ntawm kev soj ntsuam kuaj, txoj kev siv network thiab kev saib xyuas tuaj yeem pab txhawb kev nkag tau yooj yim thiab kev faib cov peev txheej rau ntau tus neeg siv, thiab kev siv engineering yooj yim.