Gabatarwa: Fiber na sadarwa ya kasu kashi ɗaya na fiber na fiber da multimode fiber bisa ga adadin hanyoyin watsawa a ƙarƙashin nauyin aikace-aikacen sa. Saboda babban diamita na fiber multimode, ana iya amfani dashi tare da ƙananan hanyoyin haske. Sabili da haka, yana da aikace-aikacen da yawa a cikin yanayin watsawa na gajeren lokaci, irin su cibiyoyin bayanai da cibiyoyin sadarwa na gida.Tare da saurin ci gaban ginin cibiyar bayanai a cikin 'yan shekarun nan, multimode fiber, wanda shine babban mahimmanci na cibiyar bayanai da yanki na gida. aikace-aikacen cibiyar sadarwa, ya kuma haifar da bazara, yana haifar da damuwa. Yau, bari muyi magana game da ci gaban fiber na multimode.
Dangane da ƙayyadaddun ƙayyadaddun ISO/IEC 11801, fiber multimode ya kasu kashi biyar manyan rukuni: OM1, OM2, OM3, OM4, da OM5. Wasiƙarsa tare da IEC 60792-2-10 an nuna shi a cikin Tebura 1. Daga cikinsu OM1, OM2 yana nufin al'ada 62.5/125mm da 50/125mm multimode fiber. OM3, OM4 da OM5 suna komawa zuwa sabon 50/125mm 10 Gigabit multimode fiber.
Na farko:na gargajiya multimode fiber
Ci gaban fiber multimode ya fara ne a cikin 1970s da 1980s. Filayen multimode na farko sun haɗa da yawa masu girma dabam, da nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i hudu. 140 μm. Saboda girman girman ƙwanƙwasa mai mahimmanci, farashin masana'anta yana da girma, juriya na lankwasawa ba shi da kyau, yawan hanyoyin watsawa ya karu, kuma an rage girman bandwidth. Therefore, the type of the large core cladding size is gradually eliminated, and two main core cladding sizes are gradually formed. Su ne 50/125 μm da 62.5/125 μm, bi da bi.
A cikin cibiyar sadarwa na farko na gida, don rage farashin tsarin tsarin cibiyar sadarwa na gida kamar yadda zai yiwu, ana amfani da LED mai ƙananan farashi a matsayin tushen haske.Saboda ƙananan ikon fitarwa na LED, kusurwar bambancin yana da girma sosai. . Koyaya, ainihin diamita da buɗaɗɗen lamba na 50/125mm fiber multi-mode fiber ne in mun gwada da ƙanƙanta, wanda bai dace da ingantacciyar haɗin gwiwa tare da LED ba. Amma ga 62.5 / 125mm fiber multimode fiber tare da babban diamita mai mahimmanci da budewa na lambobi, ƙarin ikon gani za a iya haɗa shi zuwa hanyar haɗin yanar gizo.Saboda haka, 50 / 125mm multimode fiber ba a yi amfani da shi ba kamar yadda 62.5 / 125mm multimode fiber kafin tsakiyar 1990s.
Tare da ci gaba da haɓaka ƙimar watsa LAN, tun ƙarshen ƙarni na 20, an haɓaka LAN sama da ƙimar lGb/s. Yawan bandwidth na 62.5 / 125μm multimode fiber tare da LED a matsayin tushen haske ne kawai a hankali ba zai iya cika buƙatun ba.Ya bambanta, 50 / 125mm multimode fiber yana da ƙananan ƙananan ƙididdiga da diamita na tsakiya, da ƙananan hanyoyin gudanarwa.Saboda haka, yanayin yanayin. watsawa na Multi-yanayin fiber ne yadda ya kamata rage, da kuma bandwidth da aka muhimmanci ƙara. Saboda ƙananan ƙananan diamita, farashin samarwa na 50/125mm fiber multi-mode ma ƙananan ƙananan, don haka ana amfani da shi sosai.
Daidaitaccen IEEE 802.3z Gigabit Ethernet yana ƙayyade cewa 50/125mm multimode da 62.5/125mm multimode fibers za a iya amfani da su azaman watsa labarai na Gigabit Ethernet. Koyaya, don sababbin hanyoyin sadarwa, 50/125mm multimode fiber an fi son gabaɗaya.
Na biyu:Laser inganta multimode fiber
Tare da haɓaka fasahar fasaha, 850 nm VCSEL (Vertical Cavity Surface Emitting Laser) ya bayyana. Ana amfani da Laser na VCSEL sosai saboda suna da arha fiye da laser na tsayin tsayi kuma suna iya haɓaka saurin hanyar sadarwa. Laser tsayin raƙuman ruwa kuma yana iya haɓaka saurin hanyar sadarwa.Saboda bambanci tsakanin nau'ikan nau'ikan na'urorin da ke ba da haske guda biyu, fiber kanta dole ne a canza shi don ɗaukar canje-canje a cikin hasken haske.
Domin bukatun VCSEL Laser, International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) da Telecommunications Industry Alliance (TIA) sun haɗa kai da zayyana wani sabon ma'auni don multimode fiber tare da 50mm core.ISO/IEC classified wani sabon ƙarni. na multimode fiber a cikin OM3 category (IEC misali A1a.2) a cikin sabon multimode fiber sa, wanda shi ne Laser-inganta multimode fiber.
Fiber na OM4 na gaba shine ainihin ingantaccen sigar OM3 multimode fiber. Idan aka kwatanta da fiber OM3, ma'aunin OM4 kawai yana inganta ma'aunin fiber na fiber. (OFL) a 850 nm idan aka kwatanta da fiber OM3. Kamar yadda aka nuna a Table 2 a kasa.
Akwai hanyoyin watsawa da yawa a cikin fiber multimode, kuma ana kawo matsalar juriya na fiber ɗin. Lokacin da aka lanƙwasa fiber, yanayin babban tsari yana sauƙi yayyo, yana haifar da asarar sigina, wato, lanƙwasawa asarar fiber. gaba mafi girma bukatun don juriya ta lankwasawa.
Ba kamar bayanin martaba mai sauƙi mai sauƙi na fiber mai nau'i ɗaya ba, bayanin martabar ficewar multimode yana da sarƙaƙƙiya, yana buƙatar ƙirar ƙirar bayanin martaba mai kyau da ƙirƙira. Mafi madaidaicin shirye-shiryen fiber multimode shine tsari na yanayin yanayin sinadarai na plasma (PCVD), wanda Kamfanin Changfei ke wakilta.Wannan tsari ya bambanta da sauran hanyoyin tafiyar da shi a cikin cewa yana da shimfidar wuri na yadudduka dubu da yawa da kauri na kusan 1 micron a kowane Layer lokacin. ajiya, kunna ultra-lafiya refractive index kwana iko don cimma babban bandwidth.
Ta hanyar inganta bayanin martabar index na fiber multimode, fiber multimode mai lankwasawa yana da gagarumin ci gaba a juriyar lankwasawa, kamar yadda aka nuna a hoto na 1 da ke ƙasa.
Fig.1 Kwatanta aikin macrobend tsakanin lankwasawa-resistant fiber multimode fiber na al'ada multimode fiber
Na uku:sabuwar multimode fiber (OM5)
OM3 fiber da fiber OM4 sune fiber multimode da aka fi amfani da su a cikin bandungiyar 850nm. Yayin da adadin watsawa ya ci gaba da ƙaruwa, ƙirar band ɗin tashar tashoshi ɗaya kawai zai haifar da ƙarin tsadar wayoyi, kuma haɗin haɗin gwiwa da ƙimar kulawa zai karu daidai da haka. .Saboda haka, masu fasaha suna ƙoƙari su gabatar da ra'ayi mai yawa na raƙuman raƙuman ruwa a cikin tsarin watsa multimode. Idan za a iya watsa tsawon raƙuman raƙuman ruwa da yawa akan fiber ɗaya, adadin daidaitattun fiber daidai da farashin kwanciya da kiyayewa na iya raguwa sosai.A cikin wannan mahallin, fiber OM5 ya kasance.
OM5 multimode fiber yana dogara ne akan fiber na OM4, wanda ke faɗaɗa tashar tashar bandwidth mai girma kuma yana goyan bayan aikace-aikacen watsawa daga 850nm zuwa 950nm. Aikace-aikace na yau da kullum sune SWDM4 da SR4.2 kayayyaki. SWDM4 shine maɓalli na tsawon tsayin raƙuman raƙuman ruwa guda huɗu, waɗanda sune 850 nm, 880 nm, 910 nm, da 940 nm, bi da bi. SR4.2 shine nau'i-nau'i na nau'i-nau'i na nau'i-nau'i biyu, wanda aka fi amfani dashi don fasaha na fasaha guda ɗaya-fiber.The OM5 za a iya daidaita shi tare da Laser VCSEL tare da ƙananan aiki da ƙananan farashi don mafi kyawun saduwa da sadarwa na gajeren lokaci kamar cibiyoyin bayanai.Table 3 da ke ƙasa shine kwatanta manyan ƙayyadaddun ƙayyadaddun bandwidth don OM4 da OM5 fibers.
A halin yanzu, OM5 fiber da aka yi amfani da wani sabon nau'i na high-karshen multimode fiber.One daga cikin mafi girma harkokin kasuwanci lokuta ne OM5 kasuwanci harka na Changfei da China Railways Corporation ta babban data center.The data cibiyar ne aiming a aikace-aikace abũbuwan amfãni na. OM5 fiber a cikin tsarin rabo na tsawon tsawon SR4.2. Yana cimma matsakaicin ƙarfin sadarwa a mafi ƙarancin farashi, kuma yana shirya don ƙarin ƙimar haɓakawa a nan gaba. Za a ƙara ƙimar gaba zuwa 100Gb/s ko ma 400Gb. /s, ko aikace-aikace masu faɗi, ba za su iya maye gurbin fiber ba, yana rage ƙimar haɓakawa gaba.
Takaitawa: Kamar yadda buƙatun aikace-aikacen ke ci gaba da ƙaruwa, multimode fiber yana motsawa zuwa ƙarancin lanƙwasa, babban bandwidth, da Multi-wavelength multiplexing.A cikin su, mafi kyawun aikace-aikacen shine fiber OM5, wanda ke da mafi kyawun aikin fiber multimode na yanzu, kuma yana ba da mafita mai ƙarfi na fiber don tsarin tsayin igiyoyin 100Gb / s da 400Gb / s a gaba. zaruruwa, kamar guda multimode janar-manufa zaruruwa, kuma ana ci gaba.A nan gaba, Changfei zai kaddamar da ƙarin sabon multimode fiber mafita tare da masana'antu takwarorinsu, kawo sabon ci gaba da ƙananan halin kaka zuwa data cibiyoyin da fiber optic interconnects.