1). Taw qhia
G.652 optical fiber ntau yog hom ntxov tshaj plaws ntawm ib hom kev kho qhov muag fiber ntau siv, thiab nws kuj yog qhov siv ntau tshaj plaws optical fiber hauv kev sib txuas lus. Txawm hais tias nws yog lub network ntev, ib lub network hauv zos lossis ib qho kev nkag mus rau hauv lub network, G.652 optical fiber yog qhov tseeb protagonist, thiab nws tag nrho cov kev siv nyiaj ntau dua 95%.
G.652 optical fibers muab faib ua plaub pawg a, b, c, thiab d. Yog li, qhov txawv ntawm txhua pawg subcategory yog dab tsi? Qhov no pib nrog cov yam ntxwv attenuation ntawm optical fiber thiab PMD (polarization hom dispersion) coefficient ntawm fiber ntau optical.
2). Attenuation yam ntxwv ntawm Optical Fiber
Lub attenuation coefficient ntawm cov pa ib hom fiber ntau sib txawv nrog wavelength, raws li qhia hauv daim duab hauv qab no. Vim yog qhov cuam tshuam ntawm hydroxide ions hauv cov khoom siv fiber ntau, qhov attenuation ntawm fiber ntau ntawm lub wavelength ntawm 1383nm yog qhov loj, thiab lub ncov nthwv dej yuav tshwm sim hauv daim duab, uas feem ntau hu ua "dej ncov". Yog li ntawd, cov tshuab kev sib txuas lus feem ntau zam lub 1383nm wavelength cheeb tsam.
Cov pa ib hom optical fibers muaj cov yam ntxwv zoo attenuation nyob rau hauv lub wavelength ntau ntawm 1260nm txog 1675nm (tsis suav nrog thaj tsam 1380nm). Yog li ntawd, ITU-T faib ib hom kev sib txuas lus kho qhov muag fiber ntau rau hauv O, E, S, C, L, thiab U. Optical band, lub wavelength ntau ntawm txhua pawg yog qhia hauv daim duab hauv qab no.
Hauv ob peb pawg saum toj no, tshwj tsis yog E band, ob peb lwm pawg tuaj yeem siv rau kev sib txuas lus. Qhov no tsis muaj dab tsi hlo li, tab sis tseem muaj lub tuam txhab npe hu ua Lucent uas tsis tuaj yeem sawv ntsug ntxiv lawm. Lawv tau tsim ib hom fiber ntau kho qhov muag hauv xyoo 1998. Lub attenuation nkhaus ntawm no optical fiber nyob rau hauv E-band yog tiaj, raws li qhia nyob rau hauv daim duab hauv qab no. Cov fiber ntau no tuaj yeem siv rau kev sib txuas lus hauv O, E, S, C, L, U lub teeb bands, yog li cov fiber ntau no tseem hu ua full yoj fiber, los yog dej tsis tshua muaj fiber ntau.
3). PMD coefficient ntawm optical fiber
Cov fiber ntau optical yog rub tawm los ntawm cov duab ntauwd, ib yam li cov ramen, ntu ntu ntawm cov khoom siv kho qhov muag tsis yog lub voj voog tsis tu ncua, uas ua rau lub fact tias thaum lub teeb liab optical kis tau nyob rau hauv ib hom optical fiber. , ob qho tib si perpendicular polarization hom uas muaj nyob rau hauv lub hauv paus hom yuav muab sib cais. Propagate ntawm qhov sib txawv ceev, yog li muaj lub sijhawm sib txawv thaum mus txog lwm qhov kawg ntawm fiber ntau, uas yog polarization hom dispersion, los yog PMD luv luv, raws li qhia hauv daim duab hauv qab no. Lub sij hawm sib txawv ntawm qhov ntev ntawm fiber ntau yog hu ua PMD coefficient.
Thaum qhov kev sib txuas lus tsawg tsawg, PMD tsis txaus los cuam tshuam rau kev sib kis. Raws li kev sib kis tus nqi nce, PMD dhau los ua qhov tseem ceeb cuam tshuam rau kev sib kis. Kev sib raug zoo ntawm PMD coefficient, kis tau tus mob thiab kis nrug deb yog qhia nyob rau hauv cov lus hauv qab no.
Pom tseeb, qhov me me PMD coefficient ntawm optical fiber ntau, qhov zoo dua. PMD coefficient nyob rau hauv lub teb chaws tus qauv tam sim no tau pom zoo kom tsis pub tshaj {{0}}.2ps/√km, thiab PMD coefficient ntawm cov khoom siv fiber ntau feem ntau tsis tshaj 0.1ps/√km.
4). Kev faib tawm ntawm G.652 optical fiber
Cov subcategories ntawm G.652 feem ntau txawv ntawm ob qhov ntev ntawm fiber ntau attenuation yam ntxwv thiab PMD tsis, raws li qhia nyob rau hauv cov lus hauv qab no.
5). Daim ntawv thov ntawm G.652 optical fiber
Hom fiber ntau nrog PMD coefficient loj dua qhia tau tias nws tsis tuaj yeem ua tau raws li qhov xav tau ntau dua thiab siab dua. Yog li ntawd, nrog kev txhim kho ntawm cov txheej txheem fiber ntau, G.652A thiab G.652C tau maj mam tshem tawm los ntawm kev ua lag luam.
Kev ua lag luam tam sim no muaj kev thov rau ob qho tib si G.652B thiab G.652D optical fibers. Txij li cov nqi ntawm G.652D thiab G.652B optical fibers yuav luag tib yam, qhov muag piv ntawm G.652B optical fibers yog tsawg heev (tsawg dua 5% ntawm tag nrho cov muag khoom ntawm G.652 optical fibers. %).
Txawm hais tias G.652D fiber ntau optical fiber ntau yog qhov puv-yoj optical fiber ntau, nws zoo li tsis tas yuav siv ntau lub nthwv dej rau kev sib txuas lus kho qhov muag. Piv txwv li, tam sim no DWDM feem ntau siv 80 nthwv dej hauv C-band, thiab S thiab L-bands tsis tau siv ntau xyoo. Ntxiv mus, vim qhov kev txwv ntawm cov nyhuv nonlinear ntawm optical fibers, tus naj npawb ntawm cov channel uas tuaj yeem nqa tau hauv WDM system yog txwv. Tawm tsam daim ntawv thov ntawm DWDM, tag nrho-yoj kho qhov muag fiber ntau yog qhov tsis tsim nyog.
Txhawm rau koom tes nrog kev siv tag nrho-yoj kho qhov muag fiber ntau, ITU-T tau tso tawm CWDM tus qauv hauv xyoo 2002, uas faib tag nrho-band ntawm ib hom kev kho qhov muag fiber ntau rau 18 wavelengths, thiab lub sijhawm luv ntawm txhua lub wavelength yog 20nm, raws li qhia hauv daim duab hauv qab no.
Tab sis vim tias CWDM tsis muaj qhov zoo dua piv nrog DWDM, yog li, ze li ntawm 20 xyoo tom qab tso tawm ntawm G.652D optical fiber thiab CWDM cov qauv, E-band muaj kev siv me ntsis. Txog rau ob lub xyoos dhau los, nrog rau kev siv dav dav ntawm kev faib hluav taws xob siv hluav taws xob siv CWDM thev naus laus zis hauv C-RAN (centralized xov tooj cua nkag network) tus tuav, qhov zoo ntawm G.652D optical fiber ntau tau pom zoo.
