1. Kev faib tawm ntawmFiberAcov khoom siv suab nrov
Muaj peb hom tseem ceeb ntawm cov amplifiers optical:
(1) Semiconductor Optical Amplifier (SOA, Semiconductor Optical Amplifier);
(2) Cov amplifiers fiber ntau optical uas muaj cov khoom tsis tshua muaj (erbium Er, thulium Tm, praseodymium Pr, rubidium Nd, thiab lwm yam), feem ntau yog cov amplifiers fiber uas muaj erbium doped (EDFA), nrog rau thulium-doped fiber amplifiers (TDFA) thiab praseodymium-doped fiber amplifiers (PDFA), thiab lwm yam.
(3) Cov nonlinear fiber amplifiers, feem ntau yog fiber Raman amplifiers (FRA, Fiber Raman Amplifier). Kev sib piv kev ua tau zoo ntawm cov optical amplifiers no tau qhia nyob rau hauv lub rooj.
EDFA (Erbium Doped Fiber Amplifier)
Ib lub tshuab laser ntau theem tuaj yeem tsim los ntawm kev doping cov quartz fiber nrog cov khoom tsis tshua muaj (xws li Nd, Er, Pr, Tm, thiab lwm yam), thiab lub teeb liab nkag tau ncaj qha amplified nyob rau hauv qhov kev ua ntawm lub teeb twj tso kua mis. Tom qab muab cov lus teb tsim nyog, lub laser fiber tau tsim. Lub wavelength ua haujlwm ntawm Nd-doped fiber amplifier yog 1060nm thiab 1330nm, thiab nws txoj kev loj hlob thiab daim ntawv thov raug txwv vim qhov kev hloov pauv ntawm qhov chaw nres nkoj zoo tshaj plaws ntawm kev sib txuas lus fiber optic thiab lwm yam laj thawj. Lub wavelength ua haujlwm ntawm EDFA thiab PDFA yog nyob rau hauv lub qhov rais ntawm qhov poob qis tshaj plaws (1550nm) thiab xoom dispersion wavelength (1300nm) ntawm kev sib txuas lus fiber optical, thiab TDFA ua haujlwm hauv S-band, uas yog qhov tsim nyog heev rau kev siv tshuab sib txuas lus fiber optical. Tshwj xeeb tshaj yog EDFA, qhov kev loj hlob sai tshaj plaws, tau ua tau zoo.
LubPTxoj Cai ntawm EDFA
Cov qauv yooj yim ntawm EDFA tau pom hauv Daim Duab 1 (a), uas feem ntau yog tsim los ntawm cov khoom siv nruab nrab (erbium-doped silica fiber ntev li kaum tawm meters, nrog lub hauv paus txoj kab uas hla ntawm 3-5 microns thiab qhov doping concentration ntawm (25-1000) x 10-6), lub teeb twj tso kua mis (990 lossis 1480nm LD), optical coupler thiab optical isolator. Lub teeb liab thiab lub teeb twj tso kua mis tuaj yeem nthuav dav hauv tib qho kev taw qhia (codirectional pumping), cov lus qhia sib txawv (rov qab pumping) lossis ob qho kev taw qhia (bidirectional pumping) hauv erbium fiber. Thaum lub teeb liab thiab lub teeb twj tso kua mis raug txhaj rau hauv erbium fiber tib lub sijhawm, cov erbium ions raug zoo siab rau qib zog siab nyob rau hauv qhov kev ua ntawm lub teeb twj tso kua mis (Daim Duab 1 (b), peb-theem system), thiab sai sai lwj mus rau qib zog metastable, thaum nws rov qab mus rau lub xeev hauv av nyob rau hauv qhov kev ua ntawm lub teeb liab teeb meem, nws emits photons sib raug rau lub teeb liab, yog li ntawd lub teeb liab tau amplified. Daim Duab 1 (c) yog nws cov spectrum amplified spontaneous emission (ASE) nrog lub bandwidth loj (txog li 20-40nm) thiab ob lub ncov sib xws rau 1530nm thiab 1550nm feem.
Qhov zoo tshaj plaws ntawm EDFA yog qhov nce siab, bandwidth loj, lub zog tso zis siab, kev ua haujlwm twj tso kua mis siab, kev poob qis, thiab tsis muaj kev cuam tshuam rau lub xeev polarization.
2. Teeb Meem Nrog Cov Amplifiers Fiber Optical
Txawm hais tias lub amplifier optical (tshwj xeeb tshaj yog EDFA) muaj ntau qhov zoo tshaj plaws, nws tsis yog lub amplifier zoo tagnrho. Ntxiv nrog rau lub suab nrov ntxiv uas txo SNR ntawm lub teeb liab, muaj qee qhov tsis zoo, xws li:
- Qhov tsis sib xws ntawm qhov nce spectrum hauv lub amplifier bandwidth cuam tshuam rau kev ua haujlwm ntawm ntau-channel amplification;
- Thaum cov amplifiers optical raug cascaded, cov teebmeem ntawm ASE suab nrov, fiber dispersion thiab nonlinear teebmeem yuav sib sau ua ke.
Cov teeb meem no yuav tsum tau xav txog hauv daim ntawv thov thiab kev tsim qauv system.
3. Daim Ntawv Thov ntawm Optical Amplifier hauv Optical Fiber Communication System
Hauv lub tshuab fiber optic sib txuas lus, lubFiber Optical Amplifiersiv tsis yog tsuas yog siv lub zog amplifier ntawm lub transmitter kom nce lub zog kis, tab sis kuj ua lub preamplifier ntawm lub receiver los txhim kho qhov rhiab heev tau txais, thiab tseem tuaj yeem hloov cov khoom siv kho qhov muag-hluav taws xob-kho qhov muag ib txwm muaj, kom txuas ntxiv qhov deb kis thiab paub txog kev sib txuas lus tag nrho.
Hauv cov kab ke sib txuas lus fiber ntau, cov yam tseem ceeb uas txwv qhov kev sib kis yog qhov poob thiab kev tawg ntawm cov fiber ntau. Siv lub teeb pom kev nqaim, lossis ua haujlwm ze ntawm qhov wavelength xoom-dispersion, qhov cuam tshuam ntawm kev tawg ntawm fiber yog me me. Lub kaw lus no tsis tas yuav ua tiav lub sijhawm rov ua dua tshiab (3R relay) ntawm txhua qhov chaw nres tsheb relay. Nws txaus los ua kom lub teeb liab optical nrov nrog lub amplifier optical (1R relay). Cov amplifier optical tsis tuaj yeem siv tsis yog hauv cov kab ke ntev xwb tab sis kuj siv hauv cov tes hauj lwm faib fiber ntau, tshwj xeeb tshaj yog hauv WDM systems, los ua kom ntau lub channel tib lub sijhawm.
1) Daim Ntawv Thov ntawm Optical Amplifiers hauv Trunk Optical Fiber Communication Systems
Daim Duab 2 yog daim duab qhia txog kev siv lub amplifier optical hauv lub cev sib txuas lus fiber ntau. (a) daim duab qhia tau hais tias lub amplifier optical siv ua lub zog txhawb nqa amplifier ntawm lub transmitter thiab lub preamplifier ntawm lub receiver kom qhov deb tsis yog relay yog ob npaug. Piv txwv li, kev siv EDFA, lub kaw lus kis tau tus mob Qhov deb ntawm 1.8Gb/s nce ntxiv los ntawm 120km mus rau 250km lossis txawm tias ncav cuag 400km. Daim duab 2 (b)-(d) yog daim ntawv thov ntawm cov amplifiers optical hauv ntau lub tshuab relay; Daim duab (b) yog hom 3R relay ib txwm muaj; Daim duab (c) yog hom relay sib xyaw ntawm 3R repeaters thiab optical amplifiers; Daim duab 2 (d) Nws yog hom relay tag nrho; hauv txhua lub tshuab sib txuas lus optical, nws tsis suav nrog lub sijhawm thiab rov ua dua tshiab, yog li nws yog pob tshab me ntsis, thiab tsis muaj kev txwv "electronic bottle whisker". Tsuav yog cov khoom xa thiab txais ntawm ob qho kawg hloov pauv, Nws yooj yim los hloov kho los ntawm tus nqi qis mus rau tus nqi siab, thiab lub amplifier optical tsis tas yuav hloov pauv.
2) Daim Ntawv Thov ntawm Optical Amplifier hauv Optical Fiber Distribution Network
Cov txiaj ntsig zoo ntawm cov khoom siv hluav taws xob optical (tshwj xeeb tshaj yog EDFA) muaj txiaj ntsig zoo hauv cov tes hauj lwm faib khoom broadband (xws liCATVCov tes hauj lwm). Lub network CATV ib txwm siv cov xov hlau coaxial, uas yuav tsum tau ua kom nrov dua txhua ob peb puas meters, thiab lub vojvoog kev pabcuam ntawm lub network yog li 7km. Lub network fiber ntau optical CATV siv cov amplifiers optical tsis tsuas yog ua rau muaj ntau tus neeg siv faib tawm, tab sis kuj nthuav dav txoj kev network. Cov kev txhim kho tsis ntev los no tau qhia tias kev faib tawm ntawm fiber ntau optical / hybrid (HFC) kos lub zog ntawm ob qho tib si thiab muaj kev sib tw muaj zog.
Daim Duab 4 yog ib qho piv txwv ntawm lub network faib khoom siv fiber ntau rau AM-VSB modulation ntawm 35 txoj kev TV. Lub teeb pom kev ntawm lub transmitter yog DFB-LD nrog lub wavelength ntawm 1550nm thiab lub zog tso zis ntawm 3.3dBm. Siv 4-theem EDFA ua lub zog faib khoom, nws lub zog nkag yog li -6dBm, thiab nws lub zog tso zis yog li 13dBm. Optical receiver rhiab heev -9.2d Bm. Tom qab 4 theem ntawm kev faib tawm, tag nrho cov neeg siv tau mus txog 4.2 lab, thiab txoj kev network yog ntau dua kaum tawm kilometers. Qhov hnyav teeb liab-rau-suab nrov piv ntawm qhov kev xeem yog ntau dua 45dB, thiab EDFA tsis ua rau muaj kev txo qis hauv CSO.
Lub sijhawm tshaj tawm: Plaub Hlis-23-2023