tib - hom fiber ntau
Optical fibersuas tsuas kis tau ib hom hu ua ib leeg - hom fibers. Tib hom - hom fibers tsuas yog kis tau tus qauv tseem ceeb (hom kev txiav txim qis tshaj), thiab tsis muaj inter- hom ncua qhov sib txawv. Yog li ntawd, lawv muaj ntau qhov bandwidth ntau dua li cov fibers multimode, uas yog qhov tseem ceeb rau siab -cov ntaub ntawv xa mus ceev. Lub bandwidth ntawm ib leeg - hom fibers feem ntau yog nyob rau hauv kaum ntawm GHz·km ntau lossis siab dua.
Cov qauv ntawm ib kauj ruam-index ib zaug- hom fiber ntau yog qhia hauv daim duab 2-13. Tib- hom fiber ntau muaj ib txoj kab uas hla me me los xyuas kom meej ib qho - hom kis tau tus mob, tab sis nws txoj kab uas hla cladding yog ntau tshaj kaum npaug ntawm cov tub ntxhais txoj kab uas hla kom tsis txhob optical poob.Qhov kev ua haujlwm ntawm txhua qhov ntawm ib qho - hom fiber ntau zoo ib yam li cov fiber ntau multimode. Qhov txawv yog hais tias cov tub ntxhais txoj kab uas hla yog qhia siv lub wavelength-dependent hom teb txoj kab uas hla * w *. Hom fiber ntau no yog siv dav hauv fiber ntau optic kev sib txuas lus engineering niaj hnub.
Daim duab 2-13 qhia cov qauv ntawm cov kauj ruam-index ib hom optical fiber.
Qhov ntsuas qhov ntev ntawm ib qho - hom kho qhov muag fibers ntawm hom B1.1 thiab B4 tau qhia hauv Table 2-1 thiab Table 2-2.
| Lub npe | Parameter |
|---|---|
| 1310 nm hom - teb txoj kab uas hla | [(8.6 ~ 9.5) ± 0.7] µm |
| Cladding txoj kab uas hla | (125 ± 1) µm |
| 1310nm fiber ntau concentricity yuam kev | Tsawg dua los yog sib npaug li 0.8 µm |
| Cladding tsis -circularity | Tsawg dua lossis sib npaug li 2% |
| Txheej txoj kab uas hla (xim xim) | (245 ± 10) µm |
| Txheej diam (xim) | (250 ± 15) µm |
| Cladding / txheej concentricity yuam kev | Tsawg dua lossis sib npaug li 12.5 µm |
Table 2-1 Loj Parameters ntawm B1.1 Ib Hom Fiber
| Lub npe | Parameter |
|---|---|
| 1550 nm hom - teb txoj kab uas hla | [(8.0 ~ 11.0) ± 0.7] µm |
| Cladding txoj kab uas hla | (125 ± 1) µm |
| 1550nm fiber ntau concentricity yuam kev | Tsawg dua los yog sib npaug li 0.8 µm |
| Cladding tsis -circularity | Tsawg dua lossis sib npaug li 2% |
| Txheej txoj kab uas hla (xim xim) | (245 ± 10) µm |
| Txheej diam (xim) | (250 ± 15) µm |
| Cladding / txheej concentricity yuam kev | Tsawg dua lossis sib npaug li 12.5 µm |
Table 2-2 Loj Parameters ntawm B4 Ib Hom Fiber
Cov qauv thiab kev siv ntawm ib leeg -Hom Fiber
Tib - hom fiber ntau, nrog nws qhov zoo ntawm qhov qis qis, dav bandwidth, muaj peev xwm loj, tus nqi qis, thiab kev nthuav dav yooj yim, yog qhov zoo tshaj plaws optical kev sib txuas lus nruab nrab thiab tau siv dav thoob ntiaj teb. Tam sim no, nrog kev txhim kho ntawm cov ntaub ntawv hauv zej zog, cov kws tshawb fawb tau tsim cov tshuab hluav taws xob fiber ntau, lub sijhawm - faib multiplexing (TDM), wavelength -division multiplexing (WDM), thiab zaus-division multiplexing (FDM) technologies, ntxiv kev txhim kho qhov kis tau tus mob deb, kev sib txuas lus, thiab kev sib kis tus nqi ntawm ib leeg {{5} fiber ntau.
Nws yog tsim nyog sau cia tias thaum fiber ntau amplifiers ncua kev sib kis deb thiab multiplexing technologies coj siab -ceev, siab - muaj peev xwm kis tau tus mob teeb liab, lawv kuj ua rau kom muaj kev cuam tshuam ntawm dispersion thiab nonlinear cuam tshuam rau qhov system kis tau tus mob zoo. Yog li ntawd, ntau hom optical fibers tau raug tshawb fawb thiab tsim tshwj xeeb: dispersion-hloov fiber ntau, tsis yog-zero dispersion-shifted fiber, dispersion-flattened fiber, thiab dispersion-compensated fiber, txhua tus nrog nws qhov tshwj xeeb zoo hauv kev hais txog cov teebmeem dispersion thiab nonlinear.
Tib - hom optical fibers tuaj yeem muab faib ua tsib hom raws li seb lawv puas pom qhov zero-dispersion wavelength thiab cutoff wavelength hloov. Lub International Telecommunication Union Telecommunication Standardization Sector (ITU-T) tau tshaj tawm cov lus pom zoo rau plaub hom no thaum Lub Kaum Hli 2000: G.652, G.653, G.654, thiab G.655 fibers. Cov ntawv xov xwm ntawm IEC (International Electrotechnical Commission) thiab ITU-T naming conventions rau ib leeg-hom optical fibers yog qhia nyob rau hauv daim duab 2-14.
| Suav lub npe | ITU-T | IEC |
|---|---|---|
| Tib - hom fiber ntau | ||
| Tsis yog -dispersion hloov ib qho - hom fiber ntau | G.652 A/B/C | B1.1 thiab B1.3 |
| Dispersion hloov ib qho - hom fiber ntau | G.653 | B2 |
| Txiav- tawm wavelength hloov ib zaug - hom fiber ntau | G.654 | B1.2 |
| Tsis yog -zero dispersion hloov ib qho - hom fiber ntau | G.655 A/B | B4 |
| Wideband non-zero dispersion hloov ib qho - hom fiber ntau | - | - |
| Khoov-sensitive ib leeg- hom fiber ntau | - | - |
Daim duab 2-14 qhia cov ntawv xov xwm ntawm ntau yam tib yam - hom optical fibers npe los ntawm IEC thiab ITU-T.
G.652 – Nondispersion- hloov ib zaug - hom fiber ntau
Cov ntawv nyeem ntxiv subdivides G.652 fiber ntau rau hauv G.652A, G.652B, thiab G.652C raws li nws qhov attenuation, dispersion, polarization hom dispersion, kev khiav hauj lwm wavelength ntau, thiab daim ntawv thov nyob rau hauv SDH systems ntawm txawv kis tau tus mob. Hauv qhov tseem ceeb, G.652 fiber ntau tuaj yeem muab faib ua ob hom: ib leeg ib zaug - hom fiber ntau (G.652A thiab G.652B) thiab qis- dej- ncov ib leeg- hom fiber ntau (G.652C).
(1) Ib Leeg Ib Leeg-Mode Fiber: Ib qho yooj yim - hom fiber ntau tau pib siv hauv xyoo 1983. Nws cov yam ntxwv ua tau zoo yog: xoom dispersion ntawm lub wavelength ntawm 1310 nm; yam tsawg kawg nkaus attenuation coefficient ze ntawm lub wavelength ntawm 1550 nm, kwv yees li 0.22 dB / km, tab sis qhov siab tshaj plaws dispersion coefficient ntawm 17 ps / (nm·km) ze 1550 nm; Kev ua haujlwm wavelength ntawm cov fiber ntau no tuaj yeem xaiv tau nyob rau hauv ob qho tib si 1310 nm thiab 1550 nm wavelength cheeb tsam, nrog rau nws qhov kev ua haujlwm zoo wavelength hauv thaj tsam 1310 nm. Cov fiber ntau no feem ntau hu ua "conventional" lossis "standard" single-mode fiber, thiab tam sim no nws yog fiber ntau siv. Txog niaj hnub no, nws qhov kev xa tawm thoob ntiaj teb tau mus txog 7 x 10⁻⁶ km.
(2) Tsawg- dej- ncov ib leeg- hom fiber ntau: Txhawm rau daws cov teeb meem uas tau ntsib los ntawm lub nroog cheeb tsam network (MANs) xws li cov chaw ua haujlwm nyuaj thiab sib txawv, ntau tus neeg siv ncaj qha, thiab kev sib kis luv luv (feem ntau tsuas yog 50-80 km), qhov kev daws teeb meem tau txais yog siv ntau qhov kev sib txawv ntawm qhov siab {{80}} (HDWDM) thev naus laus zis nrog kaum mus rau pua pua ntawm multiplexed wavelengths. Qhov no suav nrog kev faib cov kev pabcuam ntawm cov nqi sib txawv thiab cov yam ntxwv rau qhov sib txawv wavelengths thiab ua haujlwm routing thiab demultiplexing ntawm txoj kev kho qhov muag. Yog li ntawd, nws yog ib qho tsim nyog los txhim kho qis- dej- ncov ib leeg- hom fiber ntau (ITU-T G.652C) nrog rau kev ua haujlwm dav dav dav kom tau raws li qhov xav tau ntawm HDWDM MAN txoj kev loj hlob.
G.653 Dispersion-Hloov ib leeg-Mode Fiber
Dispersion-hloov ib leeg- hom fiber ntau (ITU-T G.653) tau ua lag luam hauv xyoo 1985. Dispersion-hloov ib zaug- hom fiber ntau ua tiav qhov no los ntawm kev hloov cov fiber ntau cov qauv tsis sib xws thiab refractive index tis 7}, nce wavebydispers tsawg kawg nkaus los ntawm 1310nm mus rau 1550nm. Qhov no ua rau qhov qis tshaj attenuation wavelength ntawm 1550 nm ua raws li xoom-dispersion wavelength, thiab nws ua haujlwm nyob rau hauv 1530-1565 nm kev khiav hauj lwm wavelength ntau ntawm ballasted fiber amplifiers. Hom fiber ntau no haum rau qhov ntev - nrug, ib leeg -channel, siab- ceev optical amplification systems; Piv txwv li, 20 Gbit / s system tuaj yeem siv ncaj qha rau ntawm cov fiber ntau no yam tsis muaj kev ntsuas kev cuam tshuam.
Daim ntawv thov kev cog lus tshaj plaws rau kev sib cais- hloov ib zaug- hom fiber ntau yog nyob rau hauv submarine fiber optic kev sib txuas lus rau ntev - nrug ib leeg -channel teeb liab kis tau tus mob. Tsis tas li ntawd, qee tus naj npawb ntawm kev sib cais - hloov ib zaug - hom fibers kuj tau muab tso rau hauv thaj av ntev - kev sib txuas lus nyob deb.
G. 654-Cutoff Wavelength Shifted Single-Mode Fiber
1550nm cutoff wavelength-hloov ib zaug-mode fiber (ITU-T G.654) yog ib qho tsis yog-dispersion-hloov fiber ntau nrog xoom-dispersion wavelength nyob ib ncig ntawm 1310nm. Lub cutoff wavelength yog hloov mus rau qhov ntev wavelength ntau yam, uas ua rau muaj tsawg attenuation nyob rau hauv 1550nm wavelength cheeb tsam. Nws qhov kev ua haujlwm zoo tshaj plaws wavelength yog 1500-1600nm.
Txoj kev kom tau txais tsawg-attenuation fiber ntau yog siv cov ntshiab silica iav core thiab fluorine-doped recessed cladding; qhov ntev cutoff wavelength txo cov fiber ntau rhiab heev rau dabtsi yog khoov-induced losses.
Vim tias hom fiber ntau no tshwj xeeb nyuaj rau kev tsim khoom thiab kim heev, nws tsis tshua siv. Nws yog tsuas yog siv nyob rau hauv repeaterless submarine fiber optic kev sib txuas lus systems nrog ntev kis tau tus mob nyob qhov twg cov khoom siv tsis tau tso.
G.655-Tsis yog-zero dispersion-hloov ib hom fiber ntau
Tsis yog-zero dispersion-hloov ib zaug- hom fiber ntau (ITU-T G.655) yog hom tshiab ntawm fiber ntau optical tsim thiab tsim nyob rau hauv 1994 los ntawm Lucent Technologies thiab Corning Incorporated tshwj xeeb rau tom ntej - tiam wavelength division multiplexing transmission systems. Cov fiber ntau no yog raws li kev sib cais- hloov pauv ib zaug- hom fiber ntau, thiab los ntawm kev hloov cov qauv ntawm refractive profile, qhov dispersion ntawm lub wavelength ntawm 1550 nm yog ua tsis yog -zero; li no lub npe tsis yog-zero dispersion-hloov ib leeg-mode fiber.
Dispersion-pav ib leeg- hom fiber ntau
Xyoo 1988, dispersion-pav ib leeg- hom fiber ntau tau ua lag luam. Cov fiber ntau no nthuav tawm qhov tsis sib haum xeeb tsawg hauv 1310-1550 nm wavelength ntau yam thiab muaj ob xoom-dispersion wavelengths, uas yog 1310 nm thiab 1550 nm. Cov fiber ntau no tuaj yeem siv tau nrog cov lasers uas muaj qhov dav dua qhov nruab nrab qhov dav thiab cov qauv lasers ua haujlwm ntawm 1310 nm thiab 1550 nm rau siab - kis tau tus mob nrog LEDs. Txawm li cas los xij, dispersion-pav ib leeg- hom fiber ntau muaj qhov nyuaj refractive index profile, ua rau nws nyuaj rau kev tsim khoom, thiab nws qhov attenuation siab txwv nws txoj kev siv tau. Kev ua tau zoo thiab kev siv ntawm kev sib cais- tiaj tus- hom fiber ntau tau qhia hauv Table 2-8.
| Kev ua tau zoo | Hom teb Diameter (μm) | Txoj kab uas hla (nm) | Zero Dispersion Wavelength (nm) | Ua haujlwm wavelength (nm) | Maxrobend poob (dB·km⁻¹) | Maximum Polarization Hom Dispersion (ps·√km)⁻¹ |
|---|---|---|---|---|---|---|
| Kev xav tau | 8 (1310 nm) 11 (1550 nm) | Tsawg dua los yog sib npaug li 125 | 1310 thiab 1550 | 1310-1550 Nws | Tsawg dua lossis sib npaug li 0.25 (1310 nm) Tsawg dua lossis sib npaug rau 0.30 (1550 nm) | 0 (1310 nm) 0 (1550 nm) |
Daim ntawv thov Scenario: Hom fiber ntau no yog tshwj xeeb tshaj yog haum rau ib puag ncig uas tsis tshua muaj bending dispersion nyob rau hauv 1310-1550 nm kev khiav hauj lwm wavelength ntau.
Dispersion-compensated ib leeg- hom fiber ntau
Nrog rau daim ntawv thov ntawm fiber ntau optic amplifiers, attenuation tsis yog ib qho tseem ceeb ntawm qhov kev ncua deb ntawm fiber optic kev sib txuas lus systems. Txawm li cas los xij, kev cuam tshuam loj heev cuam tshuam kev txhim kho thiab nthuav dav ntawm cov pa ib leeg - hom fiber ntau ua haujlwm wavelengths ntawm 1310nm txog 1550nm. Txhawm rau daws qhov teeb meem no, kev faib tawm - them nyiaj ib zaug - hom fiber ntau tau tsim.
Dispersion-compensated ib leeg- hom fiber ntau yog ib hom fiber ntau - hom fiber ntau nrog qhov cuam tshuam tsis zoo ntawm lub wavelength ntawm 1550nm. Cov txiaj ntsig kev sim tam sim no qhia tau tias qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm 50 mus rau -548 ps / (nm·km), thiab feem ntau yog 0.5 txog 1.0 dB / km.
Thaum cov kev khiav hauj lwm wavelength ntawm ib tug pa ib - hom fiber ntau yog upgraded los ntawm 1310nm mus rau 1550nm, nws tag nrho dispersion yog zoo. Los ntawm kev ntxiv ib feem ntawm qhov tsis zoo dispersion fiber ntau rau lub kaw lus, qhov zoo dispersion ntawm 1550nm hauv kaum kilometers ntawm cov pa ib leeg - hom fiber ntau tuaj yeem raug tshem tawm, yog li txhim kho cov kev khiav hauj lwm wavelength ntawm cov teeb pom kev zoo tib yam - hom fiber ntau los ntawm 1310nm rau 1550nm} siab, yog li {9} ntev-ntaus deb, thiab siab - kis tau tus mob. Lub attenuation qhia los ntawm kev sib ntxiv ntawm dispersion -compensating ib leeg- hom fiber ntau tuaj yeem them tag nrho los ntawm fiber ntau amplifier.
Multimode fiber ntau
Raws li lub npe qhia, multimode fiber ntau yog ib qho fiber ntau optical uas tso cai rau ntau hom kev xa mus rau hauv nws, lossis hauv lwm lo lus, ntau hom kev sib txuas sib cais tau tso cai muaj nyob hauv multimode fiber ntau.
Cov qauv thiab kev siv ntawm Multimode Fiber
Qib - hom multimode fiber ntau
G.651 fiber ntau yog qib -index multimode fiber ntau siv rau kev sib kis los yog cov teeb liab digital hauv thaj tsam 850nm thiab 1310nm wavelength. Nws txoj kab uas hla yog 50µm thiab nws txoj kab uas hla yog 125µm. Nyob rau hauv thaj tsam 850nm wavelength, lub attenuation coefficient tsawg dua 4dB / km thiab dispersion coefficient tsawg dua 120ps / (nm·km); nyob rau hauv cheeb tsam 1310nm wavelength, lub attenuation coefficient tsawg dua 2dB/km thiab dispersion coefficient tsawg dua 6ps/(nm·km).
Gradient{0}}mos multimode fiber ntau
Cov qauv ntawm qib -index multimode fiber ntau yog qhia hauv daim duab 2-18. Hom fiber ntau no suav nrog Ala, Alb, Alc, thiab Ald hom. Lawv tuaj yeem tsim tau siv cov iav multicomponent lossis doped silica iav. Txhawm rau txo cov fiber ntau attenuation, cov ntaub ntawv siv los fabricate qib -index multimode fibers muaj ntau purity ntau dua li cov uas siv nyob rau hauv feem ntau cov kauj ruam -index multimode fibers. Nws yog precisely vim hais tias ntawm cov qhab nia refractive index faib thiab qis attenuation uas graded -index multimode fibers outperform step-index multimode fibers.
Kauj ruam -index multimode fiber ntau
Cov qauv ntawm kauj ruam-index multimode fiber ntau yog qhia hauv daim duab 2-19. Hom fiber ntau no tuaj nyob rau hauv peb pawg (A2, A3, thiab A4) thiab cuaj ntau yam. Multicomponent iav, doped iav, los yog yas siv tau los tsim cov tub ntxhais thiab cladding. Vim lawv cov tub ntxhais loj loj thiab cov lej loj aperture, cov fibers multimode tuaj yeem ua ke zoo dua rau cov teeb pom kev tsis sib xws, xws li lub teeb -emitting diodes (LEDs). Cov kev sib txuas txuas tuaj yeem ua tau los ntawm kev txhaj tshuaj pheej yig- molded connectors, yog li txo cov nqi tsim kho network tag nrho. Yog li ntawd, kauj ruam-index multimode fiber ntau, tshwj xeeb tshaj yog A4 yas fiber ntau, ua lub luag haujlwm tseem ceeb hauv kev sib txuas lus luv luv.
