Umqondo oyisisekelo wokuxhumana kwe-fiber optical.
I-fiber optical iyi-waveguide ye-dielectric optical, isakhiwo se-waveguide esivimba ukukhanya futhi sisakaze ukukhanya ku-axial direction.
I-fiber enhle kakhulu eyenziwe ngengilazi ye-quartz, i-synthetic resin, njll.
I-fiber yemodi eyodwa: i-core 8-10um, i-cladding 125um
I-Multimode fiber: i-core 51um, i-cladding 125um
Indlela yokuxhumana yokudlulisa amasignali optical usebenzisa imicu optical ibizwa ngokuthi optical fibre communication.
Amaza okukhanya ayingxenye yesigaba samagagasi kagesi.
Ububanzi be-wavelength bokukhanya okubonakalayo bungu-390-760 nm, ingxenye enkulu kuno-760 nm ukukhanya kwe-infrared, kanti ingxenye encane kuno-390 nm ukukhanya kwe-ultraviolet.
Iwindi elisebenza ngamaza okukhanya (amawindi amathathu okuxhumana):
Ububanzi be-wavelength obusetshenziswa ekuxhumaneni kwe-fiber-optic busendaweni eseduze ne-infrared
Isifunda samaza amaza amafushane (ukukhanya okubonakalayo, okuwukukhanya okuwolintshi ngeso lenyama) ukukhanya okuwolintshi okungu-850nm
Isifunda se-wavelength ende (indawo yokukhanya engabonakali) 1310 nm (iphoyinti lokuhlakazeka eliyisisekelo), 1550 nm (iphoyinti lethiyori elincane lokuncipha)
Isakhiwo se-fiber nokuhlukaniswa
1.Isakhiwo se-fiber
Isakhiwo esihle se-fiber: i-core, i-cladding, i-coating, ijazi.
I-core kanye ne-cladding yenziwe ngezinto ze-quartz, futhi izakhiwo zemishini zibuthakathaka futhi kulula ukuphuka. Ngakho-ke, izingqimba ezimbili zesendlalelo sokumboza, uhlobo olulodwa lwe-resin kanye nongqimba olulodwa lohlobo lwenayiloni ngokuvamile zengezwa, ukuze ukusebenza okuguquguqukayo kwefiber kufinyelele izidingo ezisebenzayo zephrojekthi.
2.Ukuhlukaniswa kwama-optical fibers
(1) I-fiber ihlukaniswe ngokusho kwe-refractive index distribution of the cross section of the fibre: ihlukaniswe yaba yi-fibre yohlobo lwesinyathelo (i-fiber eyunifomu) kanye ne-fiber graded (fiber non-uniform).
Cabanga ukuthi umgogodla unenkomba ye-refractive ye-n1 kanye ne-cladding refractive index ingu-n2.
Ukuze wenze inkaba ikwazi ukudlulisa ukukhanya kumabanga amade, isimo esidingekayo sokwakha i-fiber optical ngu-n1>n2.
Ukusatshalaliswa kwenkomba ye-refractive ye-fiber eyunifomu ayishintshi
Umthetho wokusabalalisa inkomba ye-refractive ye-non-uniform fiber:
Phakathi kwazo, △ - umehluko wenkomba ye-refractive ehlobene
Α—inkomba ye-refractive, α=∞—i-fibre yokusabalalisa inkomba yesinyathelo-yesinyathelo, α=2—isikwele somthetho we-fiber refractive index distribution fiber (i-fiber ehleliwe). Le fibre iqhathaniswa neminye imicu esezingeni.Imodi yokuhlakazwa ubuncane bufanele.
(1) Ngokuya ngenani lezindlela ezidluliswa kumongo: ihlukaniswe yaba i-multimode fiber kanye ne-single mode fiber
Iphethini lapha ibhekisela ekusatshalalisweni kwenkambu yokukhanya kagesi okudluliselwa ku-fiber optical. Ukusabalalisa kwenkambu ehlukene kuyimodi ehlukile.
Imodi eyodwa (imodi eyodwa kuphela idluliselwa ku-fiber), i-multimode (izindlela eziningi zihanjiswa kanyekanye ku-fiber)
Njengamanje, ngenxa yezidingo ezikhulayo zezinga lokudlulisela kanye nenani elandayo lokudluliselwa, inethiwekhi yendawo yedolobha elikhulu iyathuthuka ibheke isivinini esikhulu namandla amakhulu, ngakho-ke iningi lawo liyimicu yemodi eyodwa. (Izici zokudlulisela ngokwayo zingcono kune-multimode fiber)
(2) Izici zefiber optical:
①Izimpawu zokulahleka kwe-fiber optical: Amaza alula adluliselwa ku-fiber optical, futhi amandla okubona ayancipha kancane kancane njengoba ibanga lokudlulisela likhula.
Izimbangela zokulahleka kwe-fiber zifaka: ukulahleka kokuhlangana, ukulahleka kokumuncwa, ukulahleka okuhlakazekayo, nokulahleka kwemisebe egobayo.
Ukulahlekelwa kokuhlanganisa ukulahlekelwa okubangelwa ukuhlangana phakathi kwefayibha nedivayisi.
Ukulahlekelwa kokumuncwa kubangelwa ukumuncwa kwamandla okukhanya ngezinto zefayibha nokungcola.
Ukulahlekelwa okuhlakazekayo kuhlukaniswe kwaba yi-Rayleigh scattering (inkomba ye-refractive non-uniformity) kanye ne-waveguide scattering (ukungalingani kwezinto).
Ukulahlekelwa kwemisebe egobekayo ukulahlekelwa okubangelwa ukugotshwa kwefayibha okuholela emisebeni yemisebe okubangelwa ukugotshwa kwefayibha.
②Izici zokuhlakazeka ze-fiber optical: Izingxenye zemvamisa ezihlukene kusiginali edluliswa i-fiber optical zinezivinini ezihlukene zokudlulisela, futhi isenzakalo esingokomzimba sokuhlanekezela okubangelwa ukunwetshwa kwe-pulse yesignali lapho ifika esigungwini ibizwa ngokuthi ukuhlakazeka.
Ukuhlakazeka kuhlukaniswe ngokuhlakazeka kwe-modal, ukuhlakazwa kwezinto ezibonakalayo, nokuhlakazwa kwe-waveguide.
Izingxenye eziyisisekelo zezinhlelo zokuxhumana zefiber optical
Thumela ingxenye:
I-pulse modulation signal okukhiphayo yi-transmitter kagesi (itheminali kagesi) ithunyelwa ku-transmitter optical (isiginali ethunyelwe uhlelo olulawulwayo.shintshakuyacutshungulwa, i-waveform iyabunjwa, okuphambene nephethini kuyashintshwa... ibe isignali kagesi efanelekile futhi ithunyelwe kusidlulisi esibonakalayo)
Indima eyinhloko yesidluliseli esibonakalayo ukuguqula isignali kagesi ibe isignali yokubona ehlanganiswe nefayibha.
Yamukela ingxenye:
Ukuguqula amasignali okubona asakazwa ngemicu yokubona abe amasignali kagesi
Ukucutshungulwa kwesiginali kagesi kubuyiselwa kusiginali eguquliwe ye-pulse yasekuqaleni futhi ithunyelwa esikhumulweni sikagesi (isignali kagesi ethunyelwe yisamukeli esibonakalayo iyacutshungulwa, i-waveform iyabunjwa, okuphambene nephethini kuyahlanekezelwa... ibuyiselwe ekuhlelwenishintsha)
Ingxenye yokudlulisela:
I-fiber yemodi eyodwa, i-optical repeater (i-electrical regenerative repeater (i-optical-electric-optical conversion amplification, ukubambezeleka kokudlulisela kuzoba kukhulu, i-pulse decision circuit izosetshenziswa ukubumba i-waveform, kanye nesikhathi), i-erbium-doped fiber Amplifier (iqedela ukukhulisa ezingeni le-optical, ngaphandle kokubunjwa kwe-waveform)
(1) I-Optical Transmitter: Kuyi-transceiver ebonakalayo eqaphela ukuguqulwa kukagesi/okubonakalayo. Iqukethe umthombo wokukhanya, umshayeli kanye ne-modulator. Umsebenzi uwukushintsha igagasi lokukhanya ukusuka emshinini kagesi ukuya kugagasi lokukhanya elikhishwa umthombo wokukhanya ukuze libe igagasi elifiphele, bese kubhanqa isignali ye-optical eshintshiwe ku-fiber optical noma intambo yokubona ukuze idluliselwe.
(2) Umamukeli obonakalayo: i-optical transceiver eqaphela ukuguqulwa kokubona/kagesi. Imodeli yokusetshenziswa yakhiwa isekethe ebona ukukhanya kanye ne-optical amplifier, futhi umsebenzi uwukuguqula isignali yokubona edluliswa i-fiber optical noma intambo yokubona ibe isignali kagesi ngomtshina obonakalayo, bese ukhulisa isignali kagesi ebuthakathaka ukuze izinga elanele ngokusebenzisa isifunda sokukhulisa ukuze sithunyelwe kusignali. Ukuphela kokuthola komshini kagesi kuyahamba.
(3) I-Fiber/Ikhebula: I-Fiber noma ikhebuli yakha indlela yokudlulisa ukukhanya. Umsebenzi uwukudlulisa isignali efiphele ethunyelwa isiphetho sokudlulisela kumtshina obonayo wendawo yokwamukela ngemva kokudluliswa kwebanga elide nge-fiber optical noma ikhebula le-optical ukuqedela umsebenzi wokudlulisa ulwazi.
(4) I-Optical repeater: iqukethe i-photodetector, umthombo wokukhanya, kanye nesifunda sokuvuselela isinqumo. Kunemisebenzi emibili: eyodwa iwukunxephezela ukuncishiswa kwesignali ye-optical edluliselwa ku-fiber optical; enye iwukulolonga ishayela lokuhlanekezelwa kwe-waveform.
(5) Izingxenye ze-Passive ezifana nezixhumi ze-fiber optic, ama-couplers (asikho isidingo sokuhlinzeka amandla ngokuhlukana, kodwa idivayisi isalahleka): Ngoba ubude befayibha noma ikhebula bunqunyelwe inqubo yokudweba i-fiber kanye nezimo zokwakha ikhebula, futhi ubude bomucu nawo bungumkhawulo (isb. 2km). Ngakho-ke, kungase kube nenkinga yokuthi ubuningi bemicu ye-optical ixhunywe emgqeni owodwa we-fiber optical. Ngakho-ke, ukuxhumana phakathi kwama-optical fibers, ukuxhuma nokuhlanganisa ama-optical fibers nama-transceivers optical, kanye nokusetshenziswa kwezingxenye ze-passive ezifana nezixhumi ze-optical nama-couplers kubalulekile.
Ukuphakama kokuxhumana kwe-fiber optical
Umkhawulokudonsa wokudlulisa, umthamo omkhulu wokuxhumana
Ukulahleka kokudlulisela okuphansi kanye nebanga elikhulu lokudlulisa
Ukuphazamiseka okuqinile kwe-anti-electromagnetic
(Ngaphandle kwe-wireless: amasignali angenantambo anemiphumela eminingi, izinzuzo ze-multipath, imiphumela yethunzi, ukufiphala kwe-Rayleigh, imiphumela ye-Doppler
Uma kuqhathaniswa nentambo ye-coaxial: isignali yokubona inkulu kunentambo ye-coaxial futhi iyimfihlo enhle)
Imvamisa yegagasi lokukhanya iphezulu kakhulu, uma iqhathaniswa namanye amaza kagesi, ukuphazamiseka kuncane.
Ukungalungi kwekhebula le-optical: izakhiwo ezingalungile zemishini, ukuphuka kalula, (ukuthuthukisa ukusebenza kwemishini, kuzoba nomthelela ekuphikiseni ukuphazamiseka), kuthatha isikhathi eside ukwakha, futhi kuthinteka izimo zendawo.