WDM yog lub thev naus laus zis sib txuas ua ke uas sib txuas ua ke ntawm cov teeb tsa kho qhov muag nqa cov ntaub ntawv tab sis sib txawv ntawm lub cev yoj mus rau hauv ib pob thiab xa lawv raws ib qho fiber ntau. Thaum tau txais qhov kawg, qhov ntsuas kab nrig ntawm lub nthwv sib txawv sib cais los ntawm qee txoj kev. Cov thev naus laus zis no tuaj yeem xa ntau cov cim ntawm ib leeg. Txhua lub teeb liab kis tau los ntawm lub teeb tshwj xeeb ntawm lub teeb.
Nyob rau hauv tib lub fiber ntau, ob lossis ntau lub koob yees duab hluav taws xob wavelength yog tib lub sijhawm sib kis los ntawm cov sib txawv kho qhov muag, uas yog hu ua optical wavelength division multiplexing (WDM). Optical wavelength division multiplexing muaj xws li zaus faib ntau yam thiab sib faib thiab sib faib. Tsis muaj qhov sib txawv ntawm qhov sib txawv ntawm zaus-faib multiplexing (FDM) thev naus laus zis thiab optical wavelength division multiplexing (WDM) thev naus laus zis, vim hais tias lub teeb ntoj hluav taws xob yog ib feem ntawm electromagnetic vuag, thiab cov zaus ntawm lub teeb muaj ib qho kev sib txuam nrog yoj yoj. Nws tseem to taub feem ntau hais tias optical zaus faib multiplexing hais txog kev cais ntawm cov khoom siv kho qhov muag, thiab cov chaw kho qhov muag tau ntom ntom heev. Optical wavelength division multiplexing yog hais txog kev sib faib ua ntu zuj zus ntawm lub khoos phis tawj, thiab cov txheej txheem kho qhov muag tau sib nrug deb, txawm tias qhov sib txawv ntawm qhov rais ntawm lub qhov muag loj.
Optical wavelength division multiplexing feem ntau siv cov nthoo sib faib wavelength multiplexer thiab demultiplexer (tseem hu ua multiplexer / demultiplexer) feem ntau tso rau ntawm ob qho kawg ntawm lub fiber kom paub sib txuas thiab sib cais ntawm lub teeb sib txawv. Lub hauv paus ntsiab lus ntawm ob lub khoom siv no yog tib yam. Lub ntsiab hom optical wavelength faib multiplexers yog fused taper type, dielectric film type, grating type thiab planar type. Nws cov yam ntxwv tseem ceeb yog qhov tsis nkag siab thiab rho tawm. Feem ntau, txij li nthwv dej faib faib ntau yam sib txuas yog siv hauv qhov txuas txuas, qhov nce ntawm qhov txuas tsis tau yog hu ua qhov tsis nkag ntawm ntab ntuag faib ua ntau yam sib kis. Thaum lub nthwv dej sib npaug 11, 12 kis los ntawm tib lub fiber ntau, qhov sib txawv ntawm lub zog ntawm cov tswv yim davhlau ya nyob twg 12 hauv qhov ntsaws thiab lub zog sib xyaw hauv 11-tso zis hluav taws xob hu ua kev rho tawm.
Cov khoom lag luam tam sim no siv WDM thev naus laus zis hauv khw feem ntau suav nrog CWDM thiab DWDM.