Nyob rau hauv xyoo tas los no, fiber ntau rau lub tsev (FTTH) tau pib muaj nuj nqis los ntawm cov tuam txhab kev sib txuas lus thoob ntiaj teb, thiab kev siv thev naus laus zis tau txhim kho sai.Muaj ob hom kab ke tseem ceeb rau FTTH broadband kev sib txuas.Cov no yog Active Optical Network (AON) thiab Passive Optical Network (PON).Txog tam sim no, feem ntau FTTH xa tawm hauv kev npaj thiab xa tawm tau siv PON kom txuag tau cov nqi fiber ntau.PON tsis ntev los no tau nyiam cov xim vim nws cov nqi qis thiab kev ua haujlwm siab.Hauv tsab xov xwm no, peb yuav qhia txog ABC ntawm PON, uas feem ntau suav nrog cov khoom siv yooj yim thiab lwm yam thev naus laus zis ntawm OLT, ONT, ONU thiab ODN.
Ua ntej, nws yog ib qho tsim nyog los qhia luv luv PON.Nyob rau hauv sib piv rau AON, ntau tus neeg siv tau txuas nrog ib qho transceiver los ntawm ib ceg ntoo ntawm optical fiber thiab passive splitter / combiner units, uas ua haujlwm tag nrho hauv qhov chaw kho qhov muag, thiab tsis muaj hluav taws xob hauv PON.Tam sim no muaj ob lub ntsiab PON qauv: Gigabit Passive Optical Network (GPON) thiab Ethernet Passive Optical Network (EPON).Txawm li cas los xij, tsis muaj teeb meem dab tsi ntawm PON, lawv txhua tus muaj tib lub ntsiab lus topology.Nws cov kab ke feem ntau muaj cov kab hluav taws xob kho qhov muag (OLT) hauv cov chaw muab kev pabcuam hauv nruab nrab thiab ntau qhov chaw kho qhov muag (ONU) lossis kho qhov muag network (ONT) nyob ze ntawm tus neeg siv kawg li optical splitters.
Optical Line Terminal (OLT)
OLT koom ua ke L2 / L3 hloov khoom siv hauv G / EPON system.Feem ntau, OLT cov cuab yeej suav nrog khib, CSM (tswj thiab hloov module), ELM (EPON txuas module, PON daim npav), kev tiv thaiv rov qab -48V DC fais fab mov module lossis 110/220V AC fais fab mov module thiab kiv cua.Nyob rau hauv cov khoom no, daim npav PON thiab cov khoom siv hluav taws xob txhawb kev sib pauv kub, thaum lwm cov qauv tsim nyob rau hauv. Lub luag haujlwm tseem ceeb ntawm OLT yog tswj ob txoj kev xa tawm cov ntaub ntawv ntawm ODN nyob rau hauv lub hauv paus chaw ua haujlwm.Qhov siab tshaj plaws kev txhawb nqa los ntawm ODN kis tau tus mob yog 20 km.OLT muaj ob txoj kev taw qhia ntab dej: sab sauv (tau txais ntau hom ntaub ntawv thiab lub suab tsheb khiav los ntawm cov neeg siv) thiab nqes dej (tau txais cov ntaub ntawv, suab thiab video tsheb los ntawm metro lossis cov chaw nyob deb, thiab xa mus rau txhua ONTs ntawm lub network Module) ODN.
Optical Network Unit (ONU)
ONU hloov cov teeb liab kho qhov muag kis tau los ntawm cov fibers optical rau hauv cov teeb liab hluav taws xob.Cov teeb liab hluav taws xob no raug xa mus rau txhua tus neeg siv.Feem ntau, muaj kev ncua deb lossis lwm yam kev nkag mus hauv network ntawm ONU thiab tus neeg siv kawg lub tsev.Tsis tas li ntawd, ONU tuaj yeem xa, sib sau ua ke thiab teeb tsa ntau hom ntaub ntawv los ntawm cov neeg siv khoom, thiab xa nws mus rau OLT.Organizing yog tus txheej txheem ntawm optimizing thiab reorganizing cov ntaub ntawv kwj, yog li nws muaj peev xwm xa tau ntau npaum li cas.OLT txhawb nqa kev faib tawm bandwidth, uas tso cai rau cov ntaub ntawv hloov mus rau OLT, uas feem ntau yog tshwm sim tam sim ntawd los ntawm cov neeg siv khoom.ONU tuaj yeem txuas tau los ntawm ntau txoj hauv kev thiab cable hom, xws li twisted khub tooj liab hlau, coaxial cable, optical fiber lossis Wi-nkaus.
Optical Network Terminal (ONT).
Qhov tseeb, ONT yog qhov tseem ceeb tib yam li ONU.ONT yog ib lub sij hawm ITU-T, thiab ONU yog lub sij hawm IEEE.Lawv txhua tus xa mus rau cov khoom siv sab nraud hauv GEPON system.Tab sis qhov tseeb, raws li qhov chaw ntawm ONT thiab ONU, muaj qee qhov sib txawv ntawm lawv.ONT feem ntau yog nyob ntawm cov neeg siv khoom thaj chaw.
Optical Distribution Network (ODN)
ODN yog ib feem tseem ceeb ntawm PON system, uas muab qhov nruab nrab kis tau tus mob rau lub cev sib txuas ntawm ONU thiab OLT.Qhov kev ncav cuag yog 20 km lossis ntau dua.Hauv ODN, optical cables, optical connectors, passive optical splitters thiab auxiliary Cheebtsam koom tes nrog ib leeg.ODN tshwj xeeb muaj tsib ntu, uas yog feeder fiber, optical tis point, tis fiber ntau, optical access point thiab incoming fiber.Lub feeder fiber yog pib los ntawm optical distribution thav duab (ODF) nyob rau hauv lub hauv paus chaw ua hauj lwm (CO) telecommunications chav tsev thiab xaus ntawm lub teeb tis taw tes rau cov kev pab mus ntev.Kev faib khoom fiber ntau los ntawm qhov chaw faib khoom kho qhov muag mus rau qhov chaw nkag mus rau qhov muag pom tau faib cov fiber ntau rau thaj tsam ntawm nws.Kev taw qhia ntawm fiber ntau txuas qhov chaw nkag mus rau qhov chaw nkag mus rau lub davhlau ya nyob twg (ONT) kom cov fiber ntau optical nkag mus rau tus neeg siv lub tsev.Tsis tas li ntawd, ODN yog txoj hauv kev tseem ceeb rau PON cov ntaub ntawv xa mus, thiab nws qhov zoo cuam tshuam ncaj qha rau kev ua haujlwm, kev ntseeg siab thiab kev ua kom muaj zog ntawm PON system.
Post lub sij hawm: Dec-31-2021