Taw qhia rau RF tshaj fiber ntau System

Taw qhia rau RF tshaj fiber ntau System

RF fiber ntauyog ib qho ntawm cov kev siv tseem ceeb ntawm microwave photonics thiab qhia tau hais tias tsis muaj qhov zoo sib xws hauv cov teb qib siab xws li microwave photonic radar, astronomical radio telephoto, thiab kev sib txuas lus hauv tsheb tsis muaj neeg siv.

RF fiber ntauROF linkyog tsim los ntawm optical transmitters, optical receivers thiab optical cables. Raws li pom hauv daim duab 1.

Optical transmitters: Distributed tawm tswv yim lasers (DFB laser) yog siv rau hauv cov ntawv thov uas tsis tshua muaj suab nrov thiab siab-dynamic ntau yam, thaum FP lasers yog siv rau hauv cov ntawv thov nrog qis dua. Cov lasers muaj wavelengths ntawm 1310nm lossis 1550nm.

Optical receiver: Ntawm qhov kawg ntawm qhov txuas fiber ntau optical, lub teeb pom los ntawm tus PIN photodiode ntawm lub receiver, uas hloov lub teeb rov qab mus rau tam sim no.

Optical cables: Nyob rau hauv sib piv rau multimode fibers, ib hom fibers yog siv nyob rau hauv linear txuas vim lawv tsis tshua muaj dispersion thiab tsawg poob. Ntawm lub wavelength ntawm 1310nm, qhov attenuation ntawm lub teeb liab optical nyob rau hauv optical fiber yog tsawg dua 0.4dB / km. Ntawm 1550nm, nws yog tsawg dua 0.25dB / km.

ROF txuas yog ib txoj kab sib kis. Raws li cov yam ntxwv ntawm linear kis tau tus mob thiab kho qhov muag kis tau tus mob, ROF txuas muaj cov nram qab no kev zoo:

• Kev poob qis heev, nrog fiber ntau attenuation tsawg dua 0.4 dB/km

• Optical fiber ntau ultra-bandwidth kis tau tus mob, optical fiber poob yog ywj siab ntawm zaus

Qhov txuas muaj lub teeb liab siab dua nqa lub peev xwm / bandwidth, mus txog DC txog 40GHz

• Anti-electromagnetic cuam tshuam (EMI) (Tsis muaj teeb liab cuam tshuam rau huab cua phem)

• Tus nqi qis dua rau ib lub 'meter' • Optical fibers hloov tau yooj yim dua thiab hnav, hnyav li ntawm 1/25 ntawm waveguides thiab 1/10 ntawm coaxial cables

• Cov txheej txheem yooj yim thiab hloov tau yooj yim (rau kev kho mob thiab tshuab ntsuas tshuab)

Raws li qhov muaj pes tsawg leeg ntawm optical transmitter, RF tshaj fiber ntau system tau muab faib ua ob hom: kev hloov kho ncaj qha thiab kev hloov kho sab nraud. Lub optical transmitter ntawm qhov ncaj-modulated RF tshaj fiber ntau system txais qhov ncaj-modulated DFB laser, uas muaj qhov zoo ntawm tus nqi qis, me me thiab kev sib koom ua ke yooj yim, thiab tau siv dav. Txawm li cas los xij, txwv los ntawm qhov ncaj qha-modulated DFB laser nti, qhov ncaj-modulated RF tshaj fiber ntau tsuas yog siv rau hauv cov zaus band hauv qab 20GHz. Piv nrog rau kev hloov pauv ncaj qha, qhov kev hloov pauv sab nraud RF tshaj fiber ntau optical transmitter yog tsim los ntawm ib zaus DFB laser thiab electro-optic modulator. Vim qhov kev loj hlob ntawm electro-optic modulator thev naus laus zis, kev hloov kho sab nraud RF tshaj fiber ntau tuaj yeem ua tiav cov ntawv thov hauv cov zaus band ntau dua 40GHz. Txawm li cas los xij, vim qhov sib ntxiv ntawm covelectro-optic modulator, lub system yog complex thiab tsis haum rau daim ntawv thov. ROF txuas nce, suab nrov thiab dynamic ntau yam yog qhov tseem ceeb ntawm ROF txuas, thiab muaj kev sib raug zoo ntawm peb. Piv txwv li, lub suab nrov qis txhais tau hais tias muaj ntau qhov sib txawv, thaum qhov kev nce siab tsis yog tsuas yog xav tau los ntawm txhua qhov system, tab sis kuj muaj kev cuam tshuam ntau dua rau lwm yam kev ua haujlwm ntawm lub cev.