Mawu Oyamba: Chingwe cholumikizira chimagawidwa kukhala fiber single mode ndi multimode CHIKWANGWANI molingana ndi kuchuluka kwa njira zopatsira pansi pakugwiritsa ntchito kwa wavelength.Choncho, ili ndi ntchito zambiri zomwe zimagwiritsidwa ntchito pazochitika zopatsirana mtunda waufupi, monga malo opangira deta ndi malo ochezera a m'deralo. maukonde ntchito, nayenso anayambitsa mu kasupe, kuchititsa nkhawa ambiri.Lero, tiyeni tikambirane za chitukuko cha multimode CHIKWANGWANI.
Malinga ndi muyezo wa ISO/IEC 11801, fiber multimode imagawidwa m'magulu akuluakulu asanu: OM1, OM2, OM3, OM4, ndi OM5. Makalata ake ndi IEC 60792-2-10 akuwonetsedwa mu Table 1. Pakati pawo OM1, OM2 amatanthauza chikhalidwe 62.5/125mm ndi 50/125mm multimode CHIKWANGWANI.OM3, OM4 ndi OM5 amatchula ulusi watsopano wa 50/125mm 10 Gigabit multimode.
Choyamba:chikhalidwe cha multimode fiber
Kukula kwa fiber multimode kunayamba mu 1970s ndi 1980s.Ulusi woyambirira wa multimode unaphatikizapo kukula kwake, ndipo mitundu inayi ya kukula kwake ikuphatikizidwa mumiyezo ya International Electrotechnical Commission (IEC) ikuphatikizapo zinayi. 140 μm. Chifukwa cha kukula kwakukulu kwazitsulo zapakati, mtengo wopangira ndi wokwera, kukana kupindika kumakhala kovutirapo, kuchuluka kwa njira zotumizira kumawonjezeka, ndipo bandwidth imachepetsedwa.Choncho, mtundu waukulu pachimake cladding kukula pang'onopang'ono kuthetsedwa, ndipo ziwiri zikuluzikulu pachimake cladding makulidwe pang'onopang'ono anapanga.Iwo ndi 50/125 μm ndi 62.5/125 μm, motero.
Kumayambiriro am'deralo, pofuna kuchepetsa mtengo wamtundu wamtundu wamtundu wapafupi momwe zingathere, LED yotsika mtengo inkagwiritsidwa ntchito ngati gwero la kuwala. .Komabe, mainchesi apakati ndi kabowo kakang'ono ka 50/125mm multi-mode fiber ndizochepa, zomwe sizingagwirizane bwino ndi LED.Ponena za 62.5 / 125mm ulusi wamitundu yambiri wokhala ndi mainchesi akulu akulu komanso kabowo kakang'ono, mphamvu yowoneka bwino imatha kuphatikizidwa ndi ulalo wa kuwala. mkatikati mwa 1990s.
Ndi kuwonjezeka kosalekeza kwa LAN transmission rate, kuyambira kumapeto kwa zaka za zana la 20, LAN yapangidwa pamwamba pa mlingo wa lGb / s.Kuthamanga kwa 62.5 / 125μm multimode fiber ndi LED monga gwero la kuwala kumangolephera pang'onopang'ono kukwaniritsa zofunika. kubalalitsidwa kwa ulusi wamitundu yambiri kumachepetsedwa bwino, ndipo bandwidth imachulukitsidwa kwambiri.Chifukwa cha mainchesi ang'onoang'ono, mtengo wopangira 50/125mm multi-mode fiber nawonso ndi wotsika, motero umagwiritsidwanso ntchito kwambiri.
Muyezo wa IEEE 802.3z Gigabit Ethernet umanena kuti 50/125mm multimode ndi 62.5/125mm multimode fibers zingagwiritsidwe ntchito ngati njira yotumizira Gigabit Ethernet.Komabe, pamanetiweki atsopano, 50/125mm multimode fiber nthawi zambiri imakonda.
Chachiwiri:laser wokometsedwa multimode CHIKWANGWANI
Ndi chitukuko chaukadaulo, 850 nm VCSEL (Vertical Cavity Surface Emitting Laser) idawonekera. Ma lasers aVCSEL amagwiritsidwa ntchito kwambiri chifukwa ndi otsika mtengo kuposa ma laser atali-wavelength ndipo amatha kuwonjezera liwiro la intaneti. lasers wavelength ndipo akhoza kuonjezera liwiro la intaneti.Chifukwa cha kusiyana pakati pa mitundu iwiri ya zipangizo zopangira kuwala, fiber yokha iyenera kusinthidwa kuti igwirizane ndi kusintha kwa magetsi.
Pazofuna za ma lasers a VCSEL, International Organisation for Standardization/International Electrotechnical Commission (ISO/IEC) ndi Telecommunications Industry Alliance (TIA) apanga mogwirizana mulingo watsopano wa fiber multimode wokhala ndi 50mm core.ISO/IEC imayika m'badwo watsopano. wa multimode CHIKWANGWANI mu gulu OM3 (IEC muyezo A1a.2) mu multimode CHIKWANGWANI kalasi yake, amene ndi laser-wokometsedwa multimode CHIKWANGWANI.
Zotsatira za OM4 fiber kwenikweni ndizowonjezereka za OM3 multimode fiber.Poyerekeza ndi OM3 fiber, muyezo wa OM4 umangowonjezera chiwerengero cha fiber bandwidth index.Ndiko kuti, OM4 fiber standard yasintha njira yogwiritsira ntchito bandwidth (EMB) ndi jekeseni wathunthu. (OFL) pa 850 nm poyerekeza ndi OM3 fiber.Monga momwe tawonetsera mu Gulu 2 pansipa.
Pali njira zambiri zopatsirana mu multimode fiber, ndipo vuto la kupindika kwa ulusi limabweretsedwanso.Ulusi ukakhala wopindika, mawonekedwe apamwamba amatsitsidwa mosavuta, zomwe zimapangitsa kuti chizindikirocho chiwonongeke, ndiko kuti, kupindika kutayika kwa fiber. patsogolo apamwamba zofunika zake kupinda kukana.
Mosiyana ndi mawonekedwe osavuta a refractive index a single-mode fiber, refractive index profile ya multimode fiber ndizovuta kwambiri, zomwe zimafunikira mawonekedwe abwino kwambiri a refractive index ndi njira yopangira. Kukonzekera bwino kwambiri kwa multimode fiber ndi ndondomeko ya plasma chemical weather deposition (PCVD), yomwe imayimiridwa ndi Changfei Company. kuyika, kupangitsa kuti ultra-fine refractive index curve control kuti mukwaniritse bandwidth yayikulu.
Mwa kukhathamiritsa mbiri ya refractive index ya multimode fiber, ulusi wa multimode wopindika umakhala ndi kusintha kwakukulu pakukana kupindika, monga momwe tawonetsera pa Chithunzi 1 pansipa.
Chithunzi 1
Chachitatu:multimode fiber (OM5)
OM3 fiber ndi OM4 fiber ndi fiber multimode yomwe imagwiritsidwa ntchito kwambiri mu gulu la 850nm. Pamene chiwerengero cha kufalitsa chikupitirira kuwonjezeka, kamangidwe kake kake kamene kadzapangitsa kuti pakhale ndalama zowonjezera zowonjezera, ndipo ndalama zoyendetsera ntchito ndi kukonza zidzawonjezeka moyenerera. .Choncho, akatswiri amayesa kuyambitsa lingaliro la wavelength division multiplexing mu multimode transmission system.Ngati mafunde angapo amatha kupatsirana pamtundu umodzi, chiwerengero chofananira cha ulusi wofanana ndi mtengo woyika ndi kukonza ukhoza kuchepetsedwa kwambiri.M'nkhaniyi, OM5 fiber inayamba.
OM5 multimode fiber imachokera ku OM4 fiber, yomwe imakulitsa njira yothamanga kwambiri ndipo imathandizira ntchito zotumizira kuchokera ku 850nm kupita ku 950nm. Ntchito zamakono zamakono ndi SWDM4 ndi SR4.2 mapangidwe.SWDM4 ndi gawo la kutalika kwa mafunde afupikitsa anayi, omwe ndi 850 nm, 880 nm, 910 nm, ndi 940 nm, motero.SR4.2 ndi magawano awiri a wavelength magawano multiplexing, makamaka amagwiritsidwa ntchito pa teknoloji imodzi-fiber bidirectional.The OM5 ikhoza kugwirizanitsidwa ndi ma lasers a VCSEL omwe ali ndi ntchito yotsika komanso yotsika mtengo kuti akwaniritse bwino kuyankhulana kwaufupi monga malo a data.Table 3 pansipa ndi Kuyerekeza kwazomwe zimapangidwira ma bandwidth a OM4 ndi OM5 fibers.
Pakalipano, OM5 fiber yakhala ikugwiritsidwa ntchito ngati mtundu watsopano wa fiber multimode wapamwamba kwambiri. Chimodzi mwazinthu zazikulu kwambiri zamalonda ndi malonda a OM5 a Changfei ndi China Railways Corporation. OM5 CHIKWANGWANI mu wavelength division dongosolo SR4.2.Iwo amakwaniritsa pazipita mphamvu kulankhulana pa mtengo wotsika, ndi kukonzekera zina Mokweza mlingo m'tsogolo.Mlingo wamtsogolo udzawonjezeka kufika ku 100Gb / s kapena ngakhale 400Gb./s, kapena ma wideband applications, sangathenso m'malo mwa fiber, kuchepetsa kwambiri mtengo wokweza mtsogolo.
Mwachidule: Pamene kufunikira kwa mapulogalamu kukukulirakulirabe, fiber multimode ikupita kumalo otsika kwambiri, bandwidth, ndi multi-wavelength multiplexing. ndipo amapereka njira yamphamvu ya fiber kwa machitidwe osiyanasiyana a 100Gb / s ndi 400Gb / s m'tsogolomu.Kuonjezera apo, kuti akwaniritse zofunikira za mayendedwe othamanga kwambiri, othamanga kwambiri, otsika mtengo, otsika mtengo, ma multimode atsopano. M'tsogolomu, Changfei idzakhazikitsa njira zatsopano zothetsera ma multimode fiber ndi anzawo amakampani, kubweretsa zopambana zatsopano komanso kutsika mtengo kwa malo opangira data ndi ma fiber optic interconnects.