Dab tsi yog qhov txhais ntawm DWDM?
DWDMyog ib tug ua ke ntawm ib txheej ntawmkho qhov muagwavelengths uas yuav kis tau los ntawm ib tug fiber. Qhov no yog lub tshuab laser siv los ua kom bandwidth ntawm cov pob txha fiber ntau uas twb muaj lawm. Tshwj xeeb tshaj yog, cov txheej txheem yog kom multiplex qhov nruj spectral spacing ntawm ib tug neeg fiber carriers nyob rau hauv ib tug muab fiber ntau coj kom zoo dua ntawm lub achievable kis tau tus mob kev ua tau zoo (piv txwv li, mus cuag tsawg dispersion los yog attenuation). Yog li, nrog rau cov ntaub ntawv xa tawm muaj peev xwm, tag nrho cov fibers xav tau tuaj yeem raug txo.
DWDM tuaj yeem ua ke thiab xa cov wavelengths sib txawv ib txhij hauv tib lub fiber ntau. Yuav kom ua tau zoo, ib qho fiber ntau tau hloov mus rau hauv ntau lub virtual fibers. Yog li, yog tias koj npaj yuav rov qab siv 8 fiber ntau cov cab kuj (OCs), uas yog, 8 lub teeb liab hauv ib lub fiber ntau, lub peev xwm kis tau los ntawm 2.5Gb / s mus rau 20Gb / s. Cov ntaub ntawv khaws tseg thaum Lub Peb Hlis 2013, vim yog kev siv thev naus laus zis DWDM, ib qho fiber ntau tuaj yeem xa tawm ntau dua 150 qhov sib txawv ntawm lub teeb nthwv dej ib txhij, thiab qhov siab tshaj plaws ntawm txhua kab teeb tuaj yeem ncav cuag 10Gb / s. Raws li cov neeg muag khoom ntxiv ntau txoj hauv kev rau txhua qhov fiber ntau, terabits ib thib ob hloov ceev yog nyob ib ncig ntawm lub ces kaum.
Ib qho txiaj ntsig tseem ceeb ntawm DWDM yog tias nws cov txheej txheem thiab kev sib kis ceev tsis cuam tshuam. DWDM-based network tuaj yeem xa cov ntaub ntawv siv IP raws tu qauv, ATM, SONET / SDH, thiab Ethernet raws tu qauv, thiab cov ntaub ntawv ua tiav yog nyob nruab nrab ntawm 100 Mb / s thiab 2.5 Gb / s. Nyob rau hauv txoj kev no, DWDM-based network tuaj yeem xa cov ntaub ntawv sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm ib lub laser channel. Los ntawm QoS (Kev Pabcuam Zoo), DWDM-based networks teb sai sai rau cov neeg siv khoom siv bandwidth thiab cov txheej txheem hloov pauv hauv tus nqi zoo.
Keeb kwm
Kev sib raug zoo ntawm kev sib txuas lus sib txuas lus thiab cov kev pabcuam tau dhau los ua qhov nyuaj hauv cov ntsiab lus ntawm cov tsheb khiav ceev ceev. Thawj TDM (fiber single-wave transmission and time-division multiplexing) tsis tuaj yeem ua tau raws li cov kev xav tau ntawm cov thev naus laus zis tshiab. Fiber optic ib leeg-yoj kis tau tus mob daim ntawv thov kev lag luam muaj qhov siab tshaj plaws ntawm 40 Gbits / s thiab kim. TDM thev naus laus zis yog qhov nyuaj rau kev hloov mus rau txoj kev sib koom tes thiab kev lag luam kev sib raug zoo. Lub tshuab fiber ntau optical fiber ntau kis tau tus mob siv cov khoom siv kho qhov muag ntshiab rau kev teem caij ntev-yoj lov qhov txwv ntawm kev ua haujlwm ceev ntawm cov khoom siv hluav taws xob. Raws li SDH thev naus laus zis, lub peev xwm nthuav dav fiber ntau tuaj yeem txhim kho tau zoo. Tam sim no kev lag luam thov tus nqi ntawm DWDM thev naus laus zis (tseem hu ua OTN thev naus laus zis) tau mus txog 3.2 Tbits / s, uas txhais tau hais tias kev sib txuas lus sib txuas tuaj yeem hloov kho kom zoo thiab hloov kho. [1]
Thawj qhov kev thov rau DWDM thev naus laus zis yog Lucent, uas nws txhais lus Suav yog ntom optical multiplexing. DWDM thev naus laus zis tau nthuav tawm hauv xyoo 1991. Tshwj xeeb, nws yog kev sib xyaw ua ke ntawm ib pab pawg ntawm cov kab hluav taws xob kho qhov muag kis tau los ntawm cov khoom siv kho qhov muag, uas yog laser tshuab siv los ua kom cov bandwidth ntawm cov pob txha fiber ntau uas twb muaj lawm. Nws tuaj yeem raug xa mus rau multiplexing qhov nruj spectral sib nrug ntawm cov neeg nqa khoom fiber ntau hauv ib qho fiber ntau kom ua tiav qhov yuav tsum tau ua thaum sib kis. Thiab koj tuaj yeem sim txo cov fibers uas koj xav tau nyob rau hauv ib qho ntawm cov ntaub ntawv xa mus. Nyob rau hauv xyoo tas los no, kev txhim kho ntawm DWDM thev naus laus zis tau txais kev saib xyuas dav, thiab DWDM thev naus laus zis yuav siv dav hauv kev sib txuas lus yav tom ntej.
Txoj Cai
Hauv kev ua haujlwm tiag tiag, txhawm rau ua kom tsim nyog siv cov peev txheej broadband tsim los ntawm ib hom fiber ntau hauv thaj tsam qis qis ntawm 1.55 teev tsaus ntuj, nws yuav tsum tau faib cov cheeb tsam qis ntawm cov fiber ntau rau hauv ntau qhov kev kho qhov muag raws li. mus rau qhov sib txawv frequencies thiab wavelengths, thiab yuav tsum tau nyob rau hauv txhua qhov Optical channel tsim cov cab kuj yoj, uas yog qhov peb hu ua optical yoj. Nyob rau tib lub sijhawm, lub splitter sib txuas cov teeb liab sib txawv ntawm qhov sib txawv wavelengths ntawm qhov kawg xa tawm, thiab cov teeb liab ua ke tau sib sau ua ke rau hauv ib qho fiber ntau rau cov teeb liab kis tau tus mob. Thaum xa mus rau qhov kawg tau txais, cov no tau ua ke nrog cov wavelengths sib txawv uas siv lub optical demultiplexer. Lub decomposition ntawm cov teeb liab ntawm lub teeb sib txawv ntawm lub teeb nyob rau hauv thawj lub xeev paub txog kev ua haujlwm ntawm kev xa xov ntau ntau ntawm cov teeb liab sib txawv hauv ib qho khoom siv kho qhov muag.
Cov qauv tsim
DWDM tau muab faib ua qauv thiab tam sim no muaj kev sib koom ua ke thiab qhib qhov system. Kev sib xyaw ua ke: Cov teeb liab kho qhov muag ntawm lub davhlau ya nyob twg ntawm ib qho khoom siv kho qhov muag uas yuav tsum tau nkag mus yog G. 692 tus qauv teeb pom kev zoo. Lub kaw lus qhib yog nyob rau pem hauv ntej kawg ntawm kev sib txuas thiab qhov kawg ntawm lub splitter, ntxiv rau lub wavelength conversion unit OTU, uas feem ntau yuav siv. Lub 957 interface wavelength hloov mus rau G. 692 tus qauv wavelength optical interface. Yog li, qhib tshuab siv wavelength conversion tshuab. Ua kom muaj kev txaus siab G. Lub teeb liab uas yuav tsum tau ua los ntawm 957 kev pom zoo tuaj yeem hloov mus rau G. los ntawm kev hloov pauv wavelength tom qab siv txoj kev yees duab-hluav taws xob-optical. Tus qauv wavelength optical teeb liab yuav tsum tau los ntawm 692 ces kis los ntawm wavelength division multiplexing ntawm DWDM system.
Tam sim no DWDM system tuaj yeem muab 16/20 nthwv dej lossis 32/40 yoj ib leeg fiber ntau kis tau tus mob, mus txog 160 nthwv dej, thiab muaj peev xwm nthuav dav. Cov neeg siv tuaj yeem tsim lub 16/20 nthwv dej thaum pib, thiab tom qab ntawd hloov mus rau 32/40 nthwv dej raws li xav tau, uas tuaj yeem txuag tau thawj zaug peev. Lub hauv paus ntsiab lus ntawm nws txoj kev hloov kho tshiab: ib qho yog txhawm rau txhim kho 16-band thiab 16-nthwv dej ntawm C-band liab mus rau 32-wave scheme; Lwm qhov yog siv Interleaver, thiab C-band tau hloov kho los ntawm 200 GHz lub sijhawm 16/32 nthwv dej mus rau 100 GHz lub sijhawm 20 / . 40 zog. Txhawm rau nthuav dav ntxiv, C ntxiv rau L band nthuav dav cov phiaj xwm tuaj yeem muab los nthuav dav ntxiv rau qhov kev sib kis tau mus rau 160 nthwv dej.
DWDMs uas tam sim no siv los ntawm cov neeg ua haujlwm loj hauv tsev feem ntau yog qhib DWDM systems. Qhov tseeb, kev sib xyaw ua ke Dense Wavelength Division Multiplexing systems muaj lawv tus kheej zoo:
1. Lub mixer thiab splitter ntawm kev sib xyaw DWDM system yog siv cais ntawm qhov pib kawg thiab qhov kawg tau txais, uas yog, tsuas yog cov khoom sib txuas ntawm lub hauv paus chiv keeb, tsuas yog lub splitter ntawm qhov kawg tau txais, thiab ob qhov kawg tau txais thiab qhov kawg xa tawm. raug tshem tawm. Cov khoom siv hloov pauv OTU (qhov no kim dua)? Yog li ntawd, kev nqis peev hauv DWDM cov cuab yeej siv tau tuaj yeem txuag tau ntau dua 60 feem pua.
2. Cov kev sib xyaw ua ke DWDM tsuas yog siv cov khoom sib txuas (xws li: cov khoom sib txuas lossis cov splitter) ntawm qhov kawg tau txais thiab qhov kawg xa tawm. Lub chaw ua haujlwm hauv xov tooj tuaj yeem txiav txim ncaj qha rau cov chaw tsim khoom, txo cov khoom txuas, thiab txo tus nqi, yog li txuag cov nqi khoom siv. .
3. Qhov qhib DWDM network tswj lub luag haujlwm yog lub luag haujlwm rau: OTM (tsuas yog OTU), OADM, OXC, EDFA saib xyuas, thiab nws cov cuab yeej siv peev nyiaj rau kwv yees li 20 feem pua ntawm tag nrho cov peev ntawm DWDM system; Thaum lub DWDM kev sib koom ua ke tsis xav tau cov cuab yeej OTM, Kev tswj xyuas lub network tsuas yog lub luag haujlwm rau kev saib xyuas OADM, OXC, thiab EDFA. Nws tuaj yeem qhia ntau tus neeg tsim khoom los sib tw, thiab nws cov nqi tswj xyuas network tuaj yeem txuag tau li ntawm ib nrab piv nrog qhib DWDM network tswj.
4. Txij li thaum lub multiplexed yoj / demultiplexing ntaus ntawv ntawm kev sib xyaw DWDM system yog ib qho khoom siv passive, nws yooj yim los muab ntau yam kev pabcuam thiab ntau tus nqi cuam tshuam, tsuav yog lub wavelength ntawm optical transceiver ntawm qhov kev pabcuam kawg ntaus ntawv ua tau raws li qhov xav tau ntawm G. Tus qauv 692 tuaj yeem siv rau txhua qhov kev pabcuam xws li PDH, SDH, POS (IP), ATM, thiab lwm yam, txhawb nqa PDH thiab SDH ntawm ntau tus nqi xws li 8M, 10M, 34M, 100M, 155M, 622M, 1G, 2.5G, thiab 10G, ATM thiab IP Ethernet? Zam kev qhib DWDM system vim OTU, tsuas yog siv tau SDH, ATM lossis IP Ethernet cov khoom siv nrog lub teeb pom kev zoo (1310nm, 1550nm) thiab tus nqi sib kis tau txiav txim los ntawm kev yuav DWDM? Nws yog tsis yooj yim sua kom siv lwm yam interfaces txhua.
5. Yog hais tias lub laser ntaus ntawv module ntawm optical kis tau tus mob cov cuab yeej xws li SDH thiab IP router yog uniformly tsim raws li tus qauv geometric loj tus pin, lub interface yog standardized, uas yog yooj yim rau tu thiab plugging, thiab kev twb kev txuas yog txhim khu kev qha. Nyob rau hauv txoj kev no, cov neeg ua haujlwm saib xyuas tuaj yeem hloov pauv lub laser lub taub hau ntawm ib qho xim wavelength raws li qhov xav tau ntawm lub wavelength ntawm DWDM kev sib koom ua ke, uas muab cov xwm txheej yooj yim rau kev ua txhaum ntawm lub taub hau laser thiab zam qhov tsis zoo uas tag nrho pawg thawj coj saib. yuav tsum tau hloov los ntawm tag nrho lub Hoobkas ua ntej. Cov nqi kho mob siab.
6. Cov xim wavelength lub teeb ci tsuas yog me ntsis kim tshaj qhov zoo tib yam 1310nm thiab 1550nm wavelength light sources. Piv txwv li, 2.5G xim wavelength lub teeb qhov chaw tam sim no ntau dua 3, 000 yuan, tab sis thaum nws txuas nrog DWDM system, nws tuaj yeem txo tus nqi ntawm cov nqi ntawm ze li 10 npaug, thiab nrog rau ntau daim ntawv thov ntawm cov xim wavelength qhov chaw, tus nqi yuav nyob ze ntawm qhov chaw teeb pom kev zoo.
7. Cov khoom siv DWDM sib xyaw ua ke yog qhov yooj yim hauv cov qauv thiab me me, thiab tsuas yog li ib feem tsib ntawm qhov chaw nyob los ntawm qhov qhib DWDM txuag cov peev txheej ntawm chav computer.
Hauv cov ntsiab lus, kev sib koom ua ke DWDM yuav tsum tau siv dav hauv ntau cov kab ke DWDM, thiab maj mam hloov qhov tseem ceeb ntawm qhov qhib DWDM system. Xav txog tias cov khoom siv kho qhov muag kis tau tus mob nrog ntau lub teeb pom kev zoo tam sim no siv hauv lub network, nws raug pom zoo kom siv kev sib xyaw thiab qhib-tshaj hybrid DWDM los tiv thaiv kev nqis peev ua ntej.
Lub hauv paus ntsiab lus
DWDM thev naus laus zis siv cov bandwidth thiab tsis tshua muaj cov yam ntxwv ntawm ib hom fiber ntau, siv ntau lub wavelengths raws li cov neeg nqa khoom, tso cai rau txhua tus neeg nqa khoom xa tawm ib txhij hauv cov fiber ntau.
Piv nrog rau universal ib leeg-channel system, ntom WDM (DWDM) tsis tsuas yog txhim kho kev sib txuas lus muaj peev xwm ntawm lub network system, tab sis kuj ua rau tag nrho siv bandwidth ntawm optical fiber ntau, thiab nws muaj ntau yam zoo xws li kev nthuav dav yooj yim thiab txhim khu kev qha. kev ua tau zoo, tshwj xeeb tshaj yog nws tuaj yeem txuas ncaj qha. Nkag mus rau ntau yam kev lag luam ua rau nws daim ntawv thov kev cia siab heev.
Hauv kev sib txuas lus sib txuas lus analog, txhawm rau ua kom siv tag nrho cov peev txheej bandwidth ntawm lub cable thiab ua rau kom muaj peev xwm kis tau tus mob, feem ntau siv ntau zaus division multiplexing method. Ntawd yog, cov teeb liab ntawm ntau txoj kev sib txuas ib txhij nyob rau hauv tib lub cable, thiab qhov kawg tau txais lim cov teeb liab ntawm txhua lub channel los ntawm kev siv lub band pass lim raws li cov neeg nqa khoom sib txawv.
Ib yam li ntawd, optical zaus division multiplexing kuj tseem siv tau rau hauv kev sib txuas lus kho qhov muag fiber ntau los ua kom muaj peev xwm kis tau tus mob. Qhov tseeb, cov txheej txheem multiplexing no zoo heev hauv kev sib txuas lus fiber ntau. Sib txawv ntawm qhov sib faib ntau zaus hauv kev sib txuas lus analog, nyob rau hauv qhov kev sib txuas lus ntawm fiber ntau, lub teeb yoj siv los ua tus cab kuj ntawm lub teeb liab, thiab qhov poob qis ntawm cov khoom siv fiber ntau tau muab faib ua ntau zaus raws li qhov zaus ( los yog wavelength) ntawm txhua channel lub teeb nthwv dej. Raws li kom ua tiav multiplexed kis tau tus mob ntawm ntau yam optical signals nyob rau hauv ib tug fiber ntau.
Txij li qee cov khoom siv kho qhov muag (xws li cov ntxaij lim dej nrog nqaim bandwidths, cov teeb pom kev sib txuas, thiab lwm yam) tseem tsis tau paub tab, nws yog ib qho nyuaj rau kev paub txog optical zaus division multiplexing (coherent optical kev sib txuas lus thev naus laus zis) nrog cov khoom siv kho qhov muag tuab heev, tab sis raws li cov cuab yeej tam sim no. theem, zaus division multiplexing ntawm optically sib cais channel tau tiav. Lub multiplexing ntawm optical channels nrog lub sijhawm loj (txawm tias nyob rau ntawm qhov sib txawv ntawm cov khoom siv kho qhov muag) feem ntau yog hu ua optical wavelength division multiplexing (WDM), thiab DWDM nrog cov channel me me nyob rau hauv tib lub qhov rais yog hu ua ntom wavelength division multiplexing (DWDM). Nrog rau kev nce qib ntawm cov thev naus laus zis, cov thev naus laus zis niaj hnub tau ua tiav nano-theem multiplexing ntawm wavelength intervals, thiab txawm tias ua tiav ob peb nanometer-scale multiplexing nrog lub wavelength ntawm xoom. Nws tsuas yog nruj dua nyob rau hauv cov kev cai ntawm lub cuab yeej, yog li 1270nm Ib pawg ntawm 20 nm wavelength rau 1610 nm yog hu ua coarse wavelength division multiplexing (CWDM).
Cov qauv thiab spectrum ntawm DWDM system yog qhia nyob rau hauv daim duab. Lub optical transmitter ntawm qhov kawg xa tawm emits optical signals nrog sib txawv wavelengths thiab raug thiab stability kom tau raws li tej yam yuav tsum tau thiab yog multiplexed ua ke los ntawm ib tug optical wavelength multiplexer los pub ib tug erbium-doped fiber ntau amplifier (lub erbium-doped fiber ntau amplifier feem ntau yog siv rau them nyiaj rau multiplexer). Lub zog poob thiab lub zog xa hluav taws xob ntawm cov teeb liab kho qhov muag tau nce ntxiv, thiab tom qab ntawd cov amplified multi-path optical teeb liab raug xa mus rau optical fiber ntau kis tau tus mob, thiab optical amplifier tuaj yeem txiav txim siab nrog lossis tsis muaj cov kab hluav taws xob kho qhov muag raws li qhov xwm txheej, thiab lub optical preamplifier tau txais ntawm qhov kawg tau txais (tsuas yog siv los ua kom tau txais kev nkag siab zoo ntxiv rau qhov kev sib kis tau ntev.
OADM thiab OXC ua haujlwm ntawm DWDM system
OADM tuaj yeem muab cov teeb liab kho qhov muag ntawm lub wavelengths ntawm txhua qhov chaw kho qhov muag raws li xav tau (tam sim no 8 nthwv dej tuaj yeem ua tiav). Qhov kev ua haujlwm no ua haujlwm nrog OXC xa cov teeb liab kho qhov muag los ntawm txhua qhov chaw nres nkoj mus rau ib qho wavelength ntawm lub kaw lus. Yog li ntawd txawm tias cov teeb liab kho qhov muag ntawm ob lub chaw nres nkoj sab saud zoo ib yam, lawv yuav tsis ua rau muaj kev thaiv. Ib yam li ntawd, qhov chaw nres nkoj txoj haujlwm tseem tuaj yeem siv los hloov qee qhov qis qis mus rau txhua qhov chaw nres nkoj raws li xav tau, uas nthuav dav qhov hloov pauv ntawm OADM daim ntawv thov. Tsis tas li ntawd, kev sib xyaw ua ke ntawm OADM thiab OXC tuaj yeem muab kev tiv thaiv hom xws li ob-fiber unidirectional multiplex seem tiv thaiv, ob-fiber bidirectional multiplex seem tiv thaiv, thiab kev tiv thaiv channel, kom lub nplhaib kho tus kheej tuaj yeem ua tiav, thiab lub kaw lus kev ua tau zoo yog kev nyab xeeb. ntseeg tau.
Kev siv DWDM thev naus laus zis hauv lub zog hluav taws xob
Kev tshwm sim ntawm cov cuab yeej sib txuas lus tshiab tsis qhia txog qhov tsis lees paub ntawm cov cuab yeej qub thiab thev naus laus zis, tab sis yuav tsum yog qhov qub txeeg qub teg, kev tsim kho thiab kev tsim kho tshiab. Lub 64k Subrate-PDH-SDH-DWDM cuam tshuam thiab ua raws li txoj cai no. Los ntawm kev soj ntsuam tam sim no ntawm daim ntawv thov ntawm cov tshuab hluav taws xob, DWDM thev naus laus zis theem ntawm wavelength division multiplexing tsis tuaj yeem hloov SDH, tab sis nws tuaj yeem koom tes nrog SDH thev naus laus zis faib, ntxiv rau ib leeg, txhim kho lub zog sib txuas lus network, ua tiav kev sib txuas lus bandwidth, thiab xyuas kom muaj kev ruaj ntseg ntawm network systems. Thiab ruaj khov.
Los ntawm tam sim no ntom ntom nti optical yoj multiplexing (DWDM) cov cuab yeej thiab thev naus laus zis, cov cuab yeej tsis tsuas yog yuav tsum siv cov khoom siv xws li optical amplifier, splitter, multiplexer, dispersion them, tab sis kuj muaj fiber ntau jumpers. Hauv txoj kev xav, DWDM piv SDH cov cuab yeej muaj qhov ua tau zoo dua ntawm kev ua tsis tiav, yog li nws tsis muaj kev tshawb fawb siv DWDM los xa cov ntaub ntawv teem sijhawm.
Los ntawm lwm qhov kev xav, DWDM, ua ib qho ntxiv thiab ntxiv rau SDH, muaj peev xwm muab kev tiv thaiv channel rau teem caij xa cov ntaub ntawv. Tsis tas li ntawd, cov ntaub ntawv tswj hwm lub network ntawm SDH yog nyob ntawm pob ntawv xa mus, thiab feem ntau ntawm lawv yog Ethernet. Yog li, WDM DWDM thev naus laus zis tuaj yeem muab kev tiv thaiv channel rau SDH kev tswj hwm network, thiab SDH tseem tuaj yeem tswj hwm DWDM network ruaj khov los muab kev tiv thaiv channel.
Peb tuaj yeem twv tau hais tias kev nce qib thiab kev siv ntawm cov teeb pom kev zoo TV multiplexing (dWDM) thev naus laus zis Qhov zoo tshaj plaws yog kev ua haujlwm siab thiab tus nqi qis. Kev tshawb fawb thiab sib faib cov kev pabcuam DWDM thiab SDH tuaj yeem muab kev ua si tag nrho rau lawv qhov zoo, txo qis kev tswj hwm kev sib txuas lus, thiab txhim kho kev sib txuas lus kev tswj hwm qib.
