Kev tsim cov txheej txheem ntawm WDM - Kev Paub

Txoj kev txhim kho

Nrog txoj kev loj hlob sai ntawm qhov kev sib txuas lus fiber ntau, kev sib txuas lus kho qhov muag tau dhau los ua lub hauv paus ntawm kev sib txuas lus niaj hnub. Cov kev sib txuas lus fiber ntau tau ntsib ntau theem kev txhim kho, los ntawm PDH system nyob rau xyoo 1980s, SDH system nyob nruab nrab xyoo 1990, WDM system, kev sib txuas lus kho qhov muag fiber ntau tau hloov kho sai. Dual-wavelength WDM (1310 / 1550nm) cov tshuab tau siv rau ntawm AT& T network hauv xyoo 1980s ntawm tus nqi ntawm 2 × 17Gb / s. WDM thev naus laus zis yog siv los hloov hom multiplexing los ntawm cov teeb liab hluav taws xob mus rau lub teeb liab kho qhov muag thawj zaug. Hauv qhov chaw sau kho qhov muag, kev faib hluav taws xob sib faib (sib npaug ntawm lub cev sib npaug) yog siv los txhawm rau txhim kho qhov sib kis. Cov cim kho qhov muag tau pom tseeb ncaj qha mus txuas ntxiv thiab ua kom nrov dua, thiab txhua lub suab yoj yob yog ywj siab los ntawm sib, uas yog pob tshab rau cov ntaub ntawv sib kis. Ib qho ntawm cov ntsiab lus kub hauv kev tshawb fawb tam sim no yog DWDM. Cov qib ntawm DWDM chav kuaj hluav taws xob tuaj yeem yog 100, 10Gbit / s, nrog kev sib pauv deb ntawm 400km; 30, 40Gbit / s, qhov ntsuas ncua deb yog 85km; 64, 5Gbit / s, qhov kev ncua deb sib txawv yog 720km. Dense wavelength division multiplexing DWDM muaj kev lag luam qib 320Gbit / s, uas yog, khub txuas ntawm cov xov hluav taws xob muaj peev xwm xa tau 4 lab kab. Kev lag luam kev lag luam tam sim no muaj peev xwm nqa nkaus li 1/100 ntawm lub peev xwm loj ntawm ib qho fiber ntau ntawm kaum tawm ntawm Tbits / s.

Kev tshawb fawb ntawm WDM thev naus laus zis pib lig hauv Suav teb. Ua ntej, WDM thev naus laus zis tau siv rau taw-rau-taw qhia kev nthuav dav ntawm cov kab kev sib tw ntev, thiab tom qab ntawd OADM thiab OXC thev naus laus zis tau siv rau kev sib txuas lus / nce ntawm nodes. Tuam Tshoj qhia thawj 8-wavelength WDM system hauv 1997 thiab nruab nws rau ntawm txoj kab tseem ceeb ntawm Xi' ib qho mus rau Wuhan. Xyoo 1998, Tuam Tshoj pib qhia txog 8 × 2.5GB / s WDM system ntawm cov khoom loj, nthuav dav thiab hloov 12 ntu ntawm cov chaw kho qhov muag hluav taws xob txuas kab hauv xov kab nrog qhov ntev tag nrho ntau dua 20,000 km. Nyob rau tib lub sijhawm, cov kab hlau ua haujlwm hauv txhua lub xeev tau ua tiav txoj cai WDM thev naus laus zis rau kev nthuav dav. Piv txwv, hauv" Nanchang - Jiujiang" optical cable peev xwm nthuav tawm qhov project, cov cuab yeej ntawm AT& T Tuam Txhab thiab lub dual-window WDM system tau saws, uas yog, ib qhov system tau ntsig txog ntawm 1310nm thiab 1550nm, ob qhov qis poob ua haujlwm ntawm lub qhov rais ntawm G.652 optical fiber. Nyob rau hauv txoj kev no, sdH2.5GB / s system tuaj yeem ntxiv los ntawm kev siv lub qhov rai tsis siv 1550nm uas tsis tshem cov thawj PDH ntaus ntawm 1310nm qhov rais. Txhawm rau kom ntseeg tau lub siab nrawm, muaj peev xwm loj thiab muaj peev xwm txaus ntawm Tuam Tshoj pob tw network kom paub tseeb tias kev ruaj ntseg network thiab kev tsim kho yav tom ntej xav tau, kev siv WDM thev naus laus zis tau ua tiav.

Hauv kev loj hlob thaum ntxov

Hauv lub sijhawm nruab nrab xyoo 1990, WDM cov tshuab tsis tau txhim kho sai heev

Lub ntsiab yog vim li cas

TDM (Sijhawm Kev Sib Tw ntau yam) kev siv thev naus laus zis, 155Mb / s-622MB / S-2.5GB / s TDM thev naus laus zis yog qhov yooj yim. Raws li kev txheeb cais, nyob rau hauv 2.5GB / s system (suav nrog 2.5GB / s system), txhua lub sijhawm hloov kho, cov nqi sib kis ib ntsis yuav raug txo txog li 30%. Yog li ntawd, TDM thev naus laus zis yog thawj lub tshuab ua kom cov neeg xav thiab siv hauv kev txhim kho cov kab ke

WDM cov khoom siv tsis tiav. WDM / demultiplexer thiab optical amplifier tau pib ua lag luam thaum xyoo 1990, thiab WDM thev naus laus zis tau tsim kho sai txij li xyoo 1995, tshwj xeeb tshaj yog 1550nm qhov rai ntom ntom ntuag Wavelength faib multiplexing (DWDM) system raws li erbium-doped fiber amplifier EDFA. Ciena qhia txog 16 × 2.5GB / s system thiab Lucent qhia txog 8 × 2.5GB / s system, uas tam sim no khiav ntawm Tb / s hauv nws LABS.

Vim li cas rau txoj kev loj hlob sai

Kev tsim kho sai ntawm optoelectronic pab kiag li lawm, tshwj xeeb tshaj yog kev paub tab thiab kev ua lag luam ntawm EDFA, ua rau nws muaj peev xwm txais WDM thev naus laus zis hauv qhov kho qhov muag loj (1530 ~ 1565nm) thaj chaw.

TDM yog ze rau qhov kev txwv ntawm silicon thiab gallium-arsenic technology, TDM tsis muaj peev xwm ntau, thiab cov khoom siv sib kis tau kim.

Qhov siab tawg ntawm 1550nm qhov rais ntawm G.652 optical fiber tau txwv kev xa ntawm TDM10Gb / s system, thiab qhov cuam tshuam ntawm optical fiber dispersion tau loj dua. WDM thev naus laus zis yog qhov yooj yim rov qab kho dua tshiab siv tshuab uas tuaj yeem ua lag luam los ntawm kev hloov ntawm hluav taws xob multiplexing mus rau kev siv kho qhov muag rov qab uas yog, siv ntau txoj kev siv ntau dhau los txhawm rau txhim kho cov txiaj ntsig sib npaug los ntawm kev siv zaus.