Tsarin asali na fiber na gani

Fiber na gani na gani yawanci ana kasu kashi uku: cibiya, cladding da shafi.

Fiber core da cladding suna kunshe da gilashi tare da ma'auni daban-daban na refractive, tsakiya shine babban gilashin gilashi mai mahimmanci (germanium-doped silica), kuma tsakiya shine ƙananan gilashin gilashin silica (tsaftataccen silica). Haske yana shiga cikin fiber a wani kusurwa na musamman na abin da ya faru, kuma jimillar fitarwa yana faruwa tsakanin fiber da cladding (saboda alamar refractive na cladding ya dan kadan fiye da ainihin), don haka yana iya yaduwa a cikin fiber.

Babban aikin suturar shine don kare fiber na gani daga lalacewa ta waje, yayin da yake ƙara haɓakar fiber na gani. Kamar yadda aka ambata a baya, ainihin da cladding an yi su ne da gilashi kuma ba za a iya lankwasa su ba. Yin amfani da murfin murfin yana kare da kuma tsawaita rayuwar fiber.

Ana ƙara Layer na kumfa na waje zuwa fiber maras tushe. Baya ga kare shi, ana kuma iya amfani da kube na waje na launuka daban-daban don bambance fiber na gani iri-iri.

Ana rarraba fiber na gani zuwa fiber yanayin guda ɗaya (Single Mode Fiber) da fiber multimode (Multi Mode Fiber) bisa ga yanayin watsawa. Haske yana shiga cikin fiber a wani takamaiman kusurwar abin da ya faru, kuma cikakkiyar fitarwa yana faruwa tsakanin fiber da cladding. Lokacin da diamita ya yi ƙanƙanta, an ba da izini guda ɗaya na haske ya wuce, wato, fiber-mode fiber; lokacin da diamita na fiber ya girma, ana iya barin haske. Allura da yadawa a kusurwoyi masu yawa, wannan lokacin ana kiransa fiber multimode.

Halayen watsa fiber na gani

Fiber na gani yana da manyan halayen watsawa guda biyu: asara da watsawa. Asarar fiber na gani yana nufin raguwar kowane tsawon raka'a na fiber na gani, a dB/km. Matsayin asarar fiber na gani kai tsaye yana rinjayar nisan watsawa na tsarin sadarwar fiber na gani ko nisa tsakanin tashoshin watsa labarai. Watsawa ta fiber yana nufin cewa siginar da fiber ke watsawa yana ɗaukar nau'ikan mitoci daban-daban da na'urori daban-daban, kuma saurin watsa nau'ikan nau'ikan mitar daban-daban da nau'ikan yanayin yanayi daban-daban sun bambanta, wanda ke haifar da karkatar da sigina.

Fiber watsawa ya kasu kashi na abu watsawa, waveguide watsawa da modal watsawa. Nau'o'i biyu na farko na tarwatsewar sigina ba ta zama mitoci ɗaya ba, kuma nau'in tarwatsewar na ƙarshe yana haifar da siginar ba yanayi ɗaya bane. Sigina ba yanayi ɗaya bane zai haifar da tarwatsa yanayin.

Single-yanayin fiber yana da asali guda ɗaya kawai, don haka akwai kawai tarwatsewar kayan abu da tarwatsa waveguide, kuma babu tarwatsawa. Multimode fiber yana da watsawa tsakanin yanayin. Watsewar fiber na gani ba wai kawai yana rinjayar ikon watsa fiber na gani ba, har ma yana iyakance nisan gudun hijira na tsarin sadarwar fiber na gani.

Single yanayin fiber

Fiber-mode (Single Mode Fiber), haske yana shiga cikin fiber a wani takamaiman kusurwar abin da ya faru, kuma cikakkiyar fitarwa yana faruwa tsakanin fiber da cladding. Lokacin da aka gajarta diamita, hanya ɗaya kawai na haske za a ba da izinin wucewa, wato fiber-mode fiber; Gilashin tsakiya na fiber yanayin yana da bakin ciki sosai, babban diamita shine gabaɗaya 8.5 ko 9.5 μm, kuma yana aiki a tsayin 1310 da 1550 nm.

Multimode fiber

Multi-mode fiber (Multi Mode Fiber) fiber ne wanda ke ba da damar watsa yanayin jagora da yawa. Babban diamita na fiber multimode shine gabaɗaya 50μm/62.5μm. Saboda ainihin diamita na fiber multimode yana da girma, yana iya ba da damar watsa nau'ikan haske daban-daban akan fiber guda ɗaya. Matsakaicin madaidaicin raƙuman ruwa na multimode sune 850nm da 1300nm bi da bi. Akwai kuma sabon ma'aunin fiber multimode mai suna WBMMF (Wideband Multimode Fiber), wanda ke amfani da tsawon zango tsakanin 850nm da 953nm.

Dukansu fiber-mode fiber da Multi-mode fiber suna da diamita cladding na 125 μm.

Single-yanayin fiber ko Multi-yanayin fiber?

Nisa watsawa

Karamin diamita na fibre-mode guda ɗaya yana sa tunani ya fi ƙarfin, yana ba da damar yanayin haske ɗaya kawai don tafiya, ta yadda siginar gani zata iya yin tafiya mai nisa. Yayin da hasken ke wucewa ta tsakiya, adadin hasken haske yana raguwa, rage raguwa da kuma haifar da ƙarin yaduwar sigina. Saboda ba shi da rarrabuwar kawuna ko ƙaramin tarwatsewar yanayi, fiber-mode fiber na iya watsa nisan kilomita 40 ko fiye ba tare da shafar siginar ba. Don haka, ana amfani da fiber mai nau'i-nau'i gabaɗaya don watsa bayanai mai nisa kuma ana amfani dashi sosai a cikin kamfanonin sadarwa da masu samar da TV na USB da jami'o'i, da sauransu.

Multimode fiber yana da babban diamita core kuma yana iya watsa haske ta hanyoyi da yawa. A cikin watsa nau'i-nau'i da yawa, saboda girman girman babban mahimmanci, yanayin tarwatsawa ya fi girma, wato, siginar gani "yana yaduwa" da sauri. Za a rage ingancin siginar yayin watsa nisa mai nisa, don haka ana amfani da fiber-mode fiber yawanci don gajeriyar nisa, aikace-aikacen sauti / bidiyo da cibiyoyin sadarwa na gida (LANs), kuma OM3 / OM4 / OM5 fiber multi-mode fiber na iya tallafawa babba. - saurin watsa bayanai.

Bandwidth, iya aiki

An ayyana bandwidth a matsayin ikon ɗaukar bayanai. Babban mahimmancin abin da ke shafar nisa na tashar watsa fiber na gani shine tarwatsawa daban-daban, wanda watsawar modal shine mafi mahimmanci. Watsewar fiber-mode guda ɗaya ƙananan ne, don haka yana iya watsa haske a cikin maɗaurin mitar mai faɗi na nesa mai nisa. Tun da Multi-mode fiber zai haifar da tsangwama, tsangwama da sauran matsaloli masu rikitarwa, ba shi da kyau a matsayin fiber-mode fiber a cikin bandwidth da iya aiki. Sabbin ƙarni na bandwidth na fiber multi-mode OM5 an saita shi zuwa 28000MHz / km, yayin da bandwidth ɗin fiber guda ɗaya ya fi girma.