Wavelength Division Multiplexing (WDM)
Wavelength Division Multiplexing (WDM) yog cov khoom siv kho qhov muag pom kev sib txawv ntawm cov wavelengths uas muaj ntau yam ntaub ntawv, uas tau ua ke ntawm qhov kawg ntawm kev xa tawm los ntawm multiplexer thiab txuas mus rau tib lub fiber ntau rau kev sib kis, thaum qhov kawg tau txais, cov teeb liab kho qhov muag ntawm ntau yam. wavelengths yog sib cais los ntawm ib tug demultiplexer. Cov txheej txheem no ntawm ib txhij xa ob lossis ntau lub teeb liab ntawm qhov sib txawv wavelengths hauv tib lub fiber ntau hu ua wavelength division multiplexing, lossis WDM. WDM thev naus laus zis tuaj yeem ua ob npaug ntawm qhov sib kis tau ntawm ib lub teeb, thiab tuaj yeem nthuav dav lub peev xwm hauv cov khoom siv kho qhov muag uas twb muaj lawm. Nyob ntawm qhov kev taw qhia ntawm cov teeb liab kis tau tus mob, WDM tuaj yeem siv rau kev sib tw lossis demultiplexing.
Kev ua haujlwm tsis zoo
Multiplexing / demultiplexing pab kiag li lawm (MUX/DEMUX) yog cov cuab yeej tseem ceeb hauv WDM, thiab lawv cuam tshuam rau kev ua haujlwm ntawm tag nrho cov kab ke. Dab tsi yog qhov kev ua haujlwm tseem ceeb ntawm cov khoom siv multiplexing / demultiplexing?
1. Ua haujlwm band
Ua haujlwm band ntawm multiplexer / demultiplexer, xws li 1550 wavelength, distinguishes peb bands: S band (short wavelength band 1460 ~ 1528nm), C band (ib txwm band 1530 ~ 1565nm), L band (ntev wavelength band 1565 ~ 16.
2. Tus naj npawb ntawm cov channel thiab qhov sib nrug ntawm cov channel
Tus naj npawb ntawm cov channel hais txog cov xov tooj ntawm cov channel uas tuaj yeem ua ke los yog sib cais los ntawm lub wavelength division multiplexer / demultiplexer. Tus lej no tuaj yeem sib txawv ntawm 4 txog 160. Tus tsim yog kho kom zoo dua los ntawm kev ntxiv ntau cov channel. Cov naj npawb ntawm cov channel feem ntau yog 4, 8, 16, 32, 40, 48, thiab lwm yam. Channel spacing yog hais txog qhov sib txawv ntawm cov neeg nqa khoom zaus ntawm ob txoj kab uas nyob ib sab thiab tuaj yeem siv los tiv thaiv kev cuam tshuam ntawm cov channel. Raws li kev pom zoo ntawm ITU-T G.692, muaj 100GHz (0.8nm), 50GHz (0.4nm) thiab 25GHz nrog qhov sib nrug tsawg dua 200GHz (1.6nm), thiab qhov sib nrug ntawm 100GHz thiab 50GHz yog tam sim no nyiam.
3. Insertion poob
Insertion poob yog qhov attenuation tshwm sim los ntawm kev nkag ntawm lub wavelength division multiplexer (WDM) nyob rau hauv ib qho optical kis tau tus mob. Lub attenuation ntawm cov teeb liab kho qhov muag los ntawm lub wavelength division multiplexer ncaj qha cuam tshuam rau kev sib kis ntawm qhov system. Feem ntau, qhov qis dua qhov poob, qhov tsawg dua qhov teeb liab yog attenuated.
4. Kev cais tawm
Qhov kev cais tawm yog hais txog qhov kev sib cais ntawm cov teeb liab ntawm txhua qhov channel, thiab qhov kev rho tawm siab muaj txiaj ntsig tuaj yeem tiv thaiv kev sib tham ntawm cov teeb liab los ntawm kev ua rau muaj kev cuam tshuam ntawm cov teeb liab kis tau tus mob.
5. Polarization Dependent Loss PDL
Lub polarization dependent poob PDL yog qhov kev ncua deb ntawm qhov siab tshaj plaws thiab qhov tsawg kawg poob los ntawm qhov sib txawv polarization xeev ntawm qhov kub thiab txias, wavelength thiab tib Band, uas yog, qhov siab tshaj qhov sib txawv ntawm qhov poob hauv tag nrho cov input polarization xeev.
