Intshayelelo kwi-RF phezu kweNkqubo yefayibha

Intshayelelo kwi-RF phezu kweNkqubo yefayibha

I-RF ngaphezulu kwefayibhayenye yezona zinto zibalulekileyo ezisetyenziswa kwi-microwave photonics kwaye ibonisa iingenelo ezingenakuthelekiswa nanto kwiinkalo eziphambili ezifana ne-microwave photonic radar, i-astronomical radio telephoto, kunye nonxibelelwano lwezithuthi zomoya ezingenamntu.

I-RF phezu kwefayibhaIkhonkco le-ROFikakhulu yenziwe zii-optical transmitters, ii-optical receivers kunye nee-optical cables. Njengoko kubonisiwe kuMfanekiso 1.

Iitransmitter ze-Optical: Iileyiza zempendulo ezisasazwayo (I-laser ye-DFB) zisetyenziswa kwiindawo ezinengxolo ephantsi kunye ne-high-dynamic range, ngelixa ii-FP lasers zisetyenziswa kwiindawo ezineemfuno eziphantsi. Ezi lasers zine-wavelengths ze-1310nm okanye i-1550nm.

Isamkeli sokubona: Kwelinye icala lekhonkco lefayibha yokubona, ukukhanya kubonwa yi-PIN photodiode yesamkeli, eguqula ukukhanya kube yi-current.

Iintambo ze-Optical: Ngokungafaniyo neentambo ze-multimode, iintambo ze-single-mode zisetyenziswa kwiikhonkco ezithe ngqo ngenxa yokusasazeka kwazo okuphantsi kunye nokulahleka okuphantsi. Kwi-wavelength ye-1310nm, ukuncitshiswa kwesignali ye-optical kwi-optical fiber kungaphantsi kwe-0.4dB/km. Kwi-1550nm, kungaphantsi kwe-0.25dB/km.

Ikhonkco le-ROF yinkqubo yothumelo oluhamba ngomgca. Ngokusekelwe kwiimpawu zothumelo oluhamba ngomgca kunye nothumelo lwe-optical, ikhonkco le-ROF linezibonelelo zobugcisa ezilandelayo:

• Ukulahleka okuphantsi kakhulu, kunye nokuncitshiswa kwefayibha okungaphantsi kwe-0.4 dB/km

• Ukudluliselwa kwe-ultra-bandwidth yefayibha ye-optical, ukulahleka kwefayibha ye-optical akuxhomekekanga kwi-frequency

Ikhonkco linomthamo ophezulu wokuthwala isignali/ububanzi bebhendi, ukuya kuthi ga kwi-DC ukuya kwi-40GHz

• Ukuphazamiseka kwe-anti-electromagnetic (EMI) (Akukho mpembelelo yesignali kwimozulu embi)

• Ixabiso eliphantsi ngemitha nganye • Iifayibha ze-optical ziguquguquka ngakumbi kwaye zilula, zinobunzima obumalunga ne-1/25 yee-waveguides kunye ne-1/10 yeentambo ze-coaxial

• Uyilo olulula noluguquguqukayo (lweenkqubo zokwenza imifanekiso yezonyango neyemishini)

Ngokwendlela ekwakhiwe ngayo i-optical transmitter, inkqubo ye-RF over fiber yahlulwe yaba ziintlobo ezimbini: i-direct modulation kunye ne-external modulation. I-optical transmitter ye-direct-modulated RF over fiber system isebenzisa i-direct-modulated laser ye-DFB, enezibonelelo zexabiso eliphantsi, ubungakanani obuncinci kunye nokudibanisa okulula, kwaye isetyenziswa kakhulu. Nangona kunjalo, inqunyelwe yi-direct-modulated DFB laser chip, i-direct-modulated RF over fiber inokusetyenziswa kuphela kwi-frequency band engaphantsi kwe-20GHz. Xa kuthelekiswa ne-direct modulation, i-external modulation RF over fiber optical transmitter yenziwe yi-single-frequency DFB laser kunye ne-electro-optic modulator. Ngenxa yokuvuthwa kwetekhnoloji ye-electro-optic modulator, inkqubo ye-external modulation RF over fiber inokufezekisa usetyenziso kwi-frequency band engaphezulu kwe-40GHz. Nangona kunjalo, ngenxa yokongezwa kwei-electro-optic modulator, inkqubo iyinkimbinkimbi ngakumbi kwaye ayilungelanga ukusetyenziswa. Ukwanda kwekhonkco le-ROF, ingxolo kunye nobubanzi obuguqukayo ziiparameter ezibalulekileyo zeekhonkco ze-ROF, kwaye kukho unxibelelwano olusondeleyo phakathi kwezi zintathu. Umzekelo, ingxolo ephantsi ithetha uluhlu olukhulu oluguqukayo, ngelixa ingxolo ephezulu ingafunwa yinkqubo nganye kuphela, kodwa ikwanempembelelo enkulu kwezinye iinkalo zokusebenza kwenkqubo.