Optical fiber yog ib qho yooj yim pob tshab fiber ntau ua los ntawm extruded iav los yog yas, uas yog me ntsis thicker dua tib neeg cov plaub hau. Optical fiber ntau yog txoj kev siv ntau tshaj plaws rau kev xa lub teeb ntawm ob qhov kawg, thiab yog siv dav hauv kev sib txuas lus fiber ntau. Optical fiber ntau muaj qhov sib kis ntev dua thiab siab dua bandwidth dua li cov kab hluav taws xob. Optical fiber feem ntau muaj qhov qis-refractive-index pob tshab core thiab pob tshab cladding khoom. Cov fiber ntau optical ua raws li lub teeb yoj tus neeg xyuas pib, uas ua rau tag nrho cov kev xav ntawm lub teeb hauv cov tub ntxhais fiber ntau.
Feem ntau hais lus, muaj ob hom optical fibers: cov uas txhawb nqa ntau txoj kev nthuav tawm lossis kev hloov pauv yog hu ua multimode fibers (MMF), thiab cov uas txhawb nqa ib hom hu ua single mode fibers (SMF). Tab sis qhov txawv ntawm lawv yog dab tsi? Nyeem tsab xov xwm no yuav pab koj tau txais cov lus teb.
1. Dab tsi yog ib hom fiber ntau?
Hauv kev sib txuas lus kho qhov muag fiber ntau, ib hom fiber ntau (SMF) yog ib qho khoom siv kho qhov muag uas ncaj qha xa cov teeb liab kho qhov muag nyob rau hauv ib hom lateral. Ib hom fiber ntau khiav ntawm cov ntaub ntawv tus nqi ntawm 100M / s lossis 1 G / s, thiab qhov sib kis tau mus txog yam tsawg kawg yog 5 km. Feem ntau, ib hom fiber ntau yog siv rau tej thaj chaw deb teeb liab kis tau tus mob.
2. Multimode fiber ntau yog dab tsi?
Multimode fiber ntau (MMF) feem ntau yog siv rau kev sib txuas lus luv luv, xws li hauv tsev lossis tsev kawm ntawv. Kev sib kis ceev yog 100M / s, kis tau tus mob mus txog 2km (100BASE-FX), 1 G / s tuaj yeem ncav cuag 1000m, 10 G / s tuaj yeem ncav cuag 550m. Muaj ob hom refractive index: graded index thiab kauj ruam index.
3. Qhov txawv ntawm ib hom thiab multimode fiber ntau yog dab tsi?
1. Core txoj kab uas hla
Qhov sib txawv tseem ceeb ntawm multimode thiab ib hom fiber ntau yog tias yav dhau los muaj txoj kab uas hla loj dua, feem ntau yog ib txoj kab uas hla ntawm 50 lossis 62.5 µm, thaum ib hom fiber ntau muaj ib txoj kab uas hla ntawm 8 thiab 10 µm, pob ntawm ob qho tib si. Cov txheej diameters yog tag nrho 125µm.
2. Lub teeb qhov chaw
Feem ntau laser thiab LED yog siv los ua lub teeb ci. Laser lub teeb qhov chaw yog kim kim dua li LED lub teeb qhov chaw vim hais tias lub teeb nws tsim muaj peev xwm tswj tau meej thiab muaj zog. Lub teeb tsim los ntawm LED teeb pom kev zoo yog qhov sib txawv (ntau hom teeb), thiab cov teeb pom kev zoo no feem ntau yog siv hauv multimode fiber jumpers. Nyob rau tib lub sijhawm, lub teeb ci laser (uas tsim lub teeb ze rau ib hom) feem ntau yog siv rau ib hom fiber ntau jumpers.
3. Bandwidth
Vim hais tias multimode fiber ntau muaj qhov loj me me dua li ib hom fiber ntau, nws txhawb ntau hom kev sib kis. Tsis tas li ntawd, zoo li multimode fibers, single-mode fibers kuj pom tias muaj kev cuam tshuam los ntawm ntau hom spatial, tab sis cov modal dispersion ntawm ib hom fibers tsawg dua multimode fibers. Vim li no, ib hom fiber ntau muaj bandwidth siab dua li multimode fiber ntau.
4. Sheath xim
Cov xim ntawm lub tsho yog qee zaum siv los paub qhov txawv ntawm multimode fiber jumpers los ntawm multimode fiber jumpers. Raws li TIA-598C tus qauv txhais, rau kev siv tsis yog tub rog, ib hom optical fibers siv lub tsho daj sab nrauv, thiab ntau hom optical fibers siv lub tsho txiv kab ntxwv lossis aqua-ntsuab. Raws li ntau hom, qee cov tuam txhab lag luam siv cov xim liab kom paub qhov txawv ntawm OM4 fiber ntau los ntawm lwm hom fiber ntau.
5. Modal dispersion
LED teeb qhov chaw yog qee zaum siv nyob rau hauv multimode fiber ntau los tsim ib tug series ntawm wavelengths uas propagate ntawm txawv speeds. Qhov no yuav ua rau muaj ntau qhov sib txawv, uas txwv qhov kev sib kis tau zoo ntawm ntau hom fiber ntau jumpers. Hauv qhov sib piv, lub laser siv los tsav ib hom fiber ntau ua rau tib lub wavelength ntawm lub teeb. Yog li ntawd, nws modal dispersion yog ntau me dua li multimode fiber ntau. Vim yog modal dispersion, multimode fiber ntau muaj cov mem tes nthuav dav ntau dua li ib hom fiber ntau, uas txwv cov ntaub ntawv kis tau tus mob ntawm multimode fiber ntau.
6. Nqe
Rau multimode fiber ntau tuaj yeem txhawb ntau hom kev kho qhov muag, nws tus nqi siab dua ib hom fiber ntau. Tab sis nyob rau hauv cov nqe lus ntawm cov cuab yeej, txij li thaum ib hom fiber ntau feem ntau siv cov khoom siv lub xeev laser diodes, cov khoom siv ntawm ib hom fiber ntau kim dua li cov khoom siv ntawm multimode fiber ntau. Yog li ntawd, tus nqi ntawm kev siv multimode fiber ntau tsawg dua tus nqi ntawm kev siv singlemode fiber ntau.
4. Hom fiber ntau yuav tsum xaiv?
Xav txog qhov kis tau tus mob nyob deb thiab tag nrho cov peev nyiaj. Yog tias qhov kev ncua deb tsawg dua li ob peb mais, multimode fiber ntau yuav ua haujlwm zoo, thiab tus nqi ntawm kev sib kis (transmitter thiab receiver) yuav nyob ntawm 3300 yuan mus rau 5300 yuan. Yog hais tias qhov kev ncua deb tshaj 6-10 kilometers, ib hom fiber ntau yuav tsum tau xaiv, tab sis vim yog tus nqi ntawm laser diodes, tus nqi ntawm cov kis tau tus mob feem ntau yuav tshaj 6700 yuan.