Lingaliro loyambira la kulumikizana kwa fiber.
An optical fiber ndi dielectric optical waveguide, mawonekedwe a waveguide omwe amalepheretsa kuwala ndikufalitsa kuwala ku axial direction.
Ulusi wabwino kwambiri wopangidwa ndi galasi la quartz, utomoni wopangira, etc.
Single mode CHIKWANGWANI: pachimake 8-10um, cladding 125um
Multimode CHIKWANGWANI: pachimake 51um, cladding 125um
Njira yolankhulirana yotumizira ma siginecha a kuwala pogwiritsa ntchito ulusi wa kuwala imatchedwa optical fiber communication.
Mafunde opepuka ali m'gulu la mafunde a electromagnetic.
Kutalika kwa mawonekedwe a kuwala ndi 390-760 nm, gawo lalikulu kuposa 760 nm ndi kuwala kwa infrared, ndipo gawo laling'ono kuposa 390 nm ndi kuwala kwa ultraviolet.
Zenera logwira ntchito lowala (mawindo atatu olumikizirana):
Kutalika kwa mafunde omwe amagwiritsidwa ntchito polumikizana ndi fiber-optic ali pafupi ndi dera la infrared
Dera lalifupi lalitali (kuwala kowoneka, komwe ndi kuwala kwalalanje ndi maso) 850nm kuwala kwa lalanje
Dera lalitali lalitali (gawo losawoneka lowala) 1310 nm (theoretical minimal dispersion point), 1550 nm (theoretical minimal attenuation point)
Kapangidwe ka fiber ndi kagawo
1.Mapangidwe a ulusi
Kapangidwe koyenera ka ulusi: pachimake, chophimba, zokutira, jekete.
Pakatikati ndi zomangira zimapangidwa ndi zinthu za quartz, ndipo zida zamakina ndizosalimba komanso zosavuta kusweka. Choncho, zigawo ziwiri za zokutira zosanjikiza, mtundu umodzi wa utomoni ndi mtundu umodzi wa nayiloni nthawi zambiri zimawonjezedwa, kotero kuti kusinthasintha kwa ulusi kumafika pazofunikira zogwiritsira ntchito polojekitiyi.
2.Kusankha kwa ulusi wa kuwala
(1) CHIKWANGWANI chimagawidwa molingana ndi kagawidwe ka refractive index ya gawo la mtanda wa CHIKWANGWANI: chimagawika mumtundu wamtundu wa fiber (yunifolomu CHIKWANGWANI) ndi graded CHIKWANGWANI (non-yunifolomu CHIKWANGWANI).
Tangoganizani kuti pachimake ali ndi refractive index ya n1 ndipo cladding refractive index ndi n2.
Pofuna kuti pakatikati pazitha kufalitsa kuwala kwa mtunda wautali, chofunikira popanga kuwala kwa kuwala ndi n1> n2.
Kugawa kwa refractive index kwa ulusi wofanana kumakhala kosasintha
Lamulo la refractive index la fiber non-uniform:
Mwa iwo, △ - wachibale refractive index index
Α-refractive index, α=∞-step-type refractive index distribution fiber, α=2-square-law refractive index distribution fiber (chingwe chokhazikika). CHIKWANGWANI ichi poyerekeza ndi zina graded fibers.Mode kubalalitsidwa osachepera mulingo woyenera kwambiri.
(1) Malinga ndi kuchuluka kwa mitundu yomwe imafalikira pachimake: imagawidwa kukhala ma multimode fiber ndi single mode fiber
Chitsanzo apa chikutanthauza kugawidwa kwa magetsi a magetsi a magetsi omwe amafalitsidwa mu fiber optical. Kugawa magawo osiyanasiyana ndi njira yosiyana.
Single mode (njira imodzi yokha imafalitsidwa mu fiber), multimode (mitundu ingapo imafalitsidwa nthawi imodzi mu fiber)
Pakalipano, chifukwa cha kuchuluka kwa zofunika pa mlingo kufala ndi kuchuluka kwa HIV, maukonde mzinda wa m'dera akukula motsogozedwa ndi liwilo lalikulu ndi mphamvu yaikulu, kotero ambiri a iwo ndi single mode anaponda ulusi. (Makhalidwe opatsirana okha ndiabwino kuposa ma multimode fiber)
(2) Makhalidwe a kuwala kwa fiber:
①Makhalidwe otayika a fiber optical: Mafunde opepuka amafalitsidwa mu fiber optical, ndipo mphamvu ya kuwala imachepa pang'onopang'ono pamene mtunda wotumizira ukuwonjezeka.
Zomwe zimayambitsa kutayika kwa ulusi ndi izi: kutayika kolumikizana, kutayika kwa mayamwidwe, kutayika kwamwazi, komanso kutayika kwa ma radiation.
Kutayika kophatikizana ndiko kuwonongeka komwe kumachitika chifukwa cha kugwirizana pakati pa ulusi ndi chipangizocho.
Kutayika kwa mayamwidwe kumachitika chifukwa cha kuyamwa kwa mphamvu yowunikira ndi zinthu za fiber ndi zonyansa.
Kutayika kobalalika kumagawidwa mu Rayleigh kubalalitsa (refractive index non-uniformity) ndi kufalikira kwa waveguide (kusagwirizana kwazinthu).
Kutayika kwa ma radiation ndi kuwonongeka komwe kumachitika chifukwa cha kupindika kwa ulusi womwe umatsogolera kumayendedwe a radiation chifukwa cha kupindika kwa ulusi.
②Makhalidwe obalalika a fiber optical: Magawo osiyanasiyana amafupipafupi omwe amafalitsidwa ndi fiber fiber amakhala ndi liwiro losiyana, ndipo kupotoza kwakuthupi komwe kumachitika chifukwa cha kufalikira kwa ma siginecha kukafika ku terminal kumatchedwa dispersion.
Kubalalitsidwa kumagawidwa mu modal kubalalitsidwa, kufalikira kwa zinthu, ndi kufalikira kwa ma waveguide.
Zigawo zoyambira zamakina olumikizirana optical fiber
Tumizani gawo:
Kutulutsa kwa ma pulse modulation ndi chotumizira magetsi (electrical terminal) kumatumizidwa ku transmitter yamagetsi (chizindikiro chotumizidwa ndi pulogalamu yoyendetsedwa ndi pulogalamuyo).kusinthaimakonzedwa, mawonekedwe ake amawumbidwa, mawonekedwe ake amasinthidwa… kukhala chizindikiro chamagetsi choyenera ndikutumizidwa ku chowulutsira kuwala)
Ntchito yayikulu ya transmitter optical ndikusintha siginecha yamagetsi kukhala siginecha ya kuwala yomwe imaphatikizidwa mu ulusi.
Gawo lolandira:
Kutembenuza zizindikiro za kuwala zomwe zimafalitsidwa kudzera muzitsulo za kuwala kukhala zizindikiro zamagetsi
Kukonzekera kwa siginecha yamagetsi kumabwezeretsedwa ku chizindikiro choyambirira cha pulse modulated ndikutumizidwa ku terminal yamagetsi (chizindikiro chamagetsi chomwe chimatumizidwa ndi cholandila chamagetsi chimakonzedwa, mawonekedwe amawumbidwa, mawonekedwe ake amasinthidwa ... yatumizidwanso ku programmablekusintha)
Gawo lotumizira:
Single-mode fiber, optical repeater (electric regenerative repeater (optical-electric-optical conversion amplification, kuchedwa kutumizira kudzakhala kokulirapo, chigawo cha chisankho chidzagwiritsidwa ntchito kupanga mawonekedwe a waveform, ndi nthawi), erbium-doped fiber Amplifier (imaliza kukulitsa pamlingo wa kuwala, popanda mawonekedwe a waveform)
(1) Optical transmitter: Ndi transceiver yamagetsi yomwe imazindikira kutembenuka kwamagetsi / kuwala. Zili ndi gwero lowala, dalaivala ndi modulator. Ntchitoyi ndikusintha mafunde a kuwala kuchokera pamakina amagetsi kupita kumafunde owunikira omwe amaperekedwa ndi gwero la kuwala kuti akhale mafunde ocheperako, kenako ndikuphatikiza siginecha yowoneka bwino ndi chingwe cha kuwala kapena chingwe cholumikizira.
(2) Optical receiver: ndi transceiver ya kuwala yomwe imazindikira kutembenuka kwa kuwala / magetsi. Chitsanzo chothandizira chimapangidwa ndi chowunikira chowunikira kuwala ndi amplifier optical, ndipo ntchitoyo ndikusintha chizindikiro cha kuwala chomwe chimaperekedwa ndi fiber optical kapena chingwe cha kuwala kukhala chizindikiro chamagetsi ndi chowunikira chowunikira, ndiyeno kukulitsa chizindikiro chofooka chamagetsi kuti chikhale chizindikiro cha magetsi. mlingo wokwanira kudzera mu dera lokulitsa kuti litumizidwe ku chizindikiro. Mapeto olandila a makina amagetsi amapita.
(3) CHIKWANGWANI/Chingwe: CHIKWANGWANI kapena chingwe chimapanga njira yotumizira kuwala. Ntchitoyi ndikutumiza chizindikiro cha dimmed chomwe chimatumizidwa ndi mapeto otumizira ku detector optical ya mapeto olandira pambuyo pa kufalikira kwa mtunda wautali kudzera mu fiber optical kapena optical cable kuti amalize ntchito yotumizira uthenga.
(4) Optical repeater: imakhala ndi photodetector, gwero la kuwala, ndi dera lokonzanso chisankho. Pali ntchito ziwiri: imodzi ndi kubweza attenuation wa kuwala siginecha opatsirana mu CHIKWANGWANI kuwala; chinacho ndi kupanga kugunda kwa mawonekedwe a waveform kupotoza.
(5) Zigawo zopanda kanthu monga zolumikizira za fiber optic, ma couplers (palibe chifukwa choperekera mphamvu padera, koma chipangizocho chimakhala chotayika): Chifukwa kutalika kwa ulusi kapena chingwe kumachepetsedwa ndi njira yojambulira ulusi ndi mikhalidwe yomanga chingwe, ndi kutalika kwa ulusi ndi malire (mwachitsanzo 2km). Chifukwa chake, pangakhale vuto kuti kuchuluka kwa ulusi wa kuwala kumalumikizidwa mumzere umodzi wa fiber. Chifukwa chake, kulumikizana pakati pa ulusi wa kuwala, kulumikizana ndi kulumikizana kwa ulusi wa kuwala ndi ma transceivers owoneka, komanso kugwiritsa ntchito zinthu zomwe zili ngati zolumikizira ndi zolumikizira ndizofunikira kwambiri.
Kupambana kwa optical fiber communication
Kutumiza kwa bandwidth, kulumikizana kwakukulu
Kutaya kwapang'onopang'ono komanso mtunda waukulu wotumizirana mauthenga
Kusokoneza kwamphamvu kwa anti-electromagnetic
(Kupitilira opanda zingwe: ma siginecha opanda zingwe ali ndi zotsatira zambiri, maubwino ochulukitsa, zotsatira za mthunzi, Rayleigh kuzimiririka, zotsatira za Doppler
Poyerekeza ndi chingwe coaxial: chizindikiro cha kuwala ndi chachikulu kuposa chingwe coaxial ndipo chimakhala ndi chinsinsi chabwino)
Mafupipafupi a mafunde a kuwala ndi okwera kwambiri, poyerekeza ndi mafunde ena a electromagnetic, kusokoneza kumakhala kochepa.
Kuipa kwa chingwe cha kuwala: kuwonongeka kwa makina, kosavuta kuthyoka, (kupititsa patsogolo makina ogwirira ntchito, kudzakhudza kusokoneza kusokoneza), zimatenga nthawi yaitali kumanga, ndipo zimakhudzidwa ndi malo.