Iinxalenye ezingasebenziyo kwiisekethe zeRF
Iiresistor, ii-capacitors, ii-Antennas. . . . Funda ngezinto ezingasebenziyo ezisetyenziswa kwiinkqubo ze-RF.
Iinkqubo zeRF azihlukanga ngokupheleleyo kwezinye iintlobo zeesekethe zombane. Imithetho efanayo yefiziksi iyasebenza, kwaye ngenxa yoko izinto ezisisiseko ezisetyenziswa kuyilo lweRF zikwafumaneka kwiisekethe zedijithali nakwiisekethe ze-analog ezisebenzisa i-frequency ephantsi.
Nangona kunjalo, uyilo lwe-RF lubandakanya imingeni neenjongo ezizodwa, kwaye ngenxa yoko iimpawu kunye nokusetyenziswa kwezinto kufuna ingqwalasela ekhethekileyo xa sisebenza kumxholo we-RF. Kwakhona, ezinye iisekethe ezidibeneyo zenza umsebenzi okhethekileyo kwiinkqubo ze-RF—azisetyenziswa kwiisekethe ezisebenzisa i-frequency ephantsi kwaye zisenokungaqondwa kakuhle ngabo bangenamava kangako ngeendlela zoyilo lwe-RF.
Sihlala sihlela izinto ezisetyenziswayo ngokwezigaba njengezinto ezisebenzayo okanye ezingasebenziyo, kwaye le ndlela isebenza ngokulinganayo kwicandelo le-RF. Iindaba zixoxa ngezinto ezingasebenziyo ngokukodwa ngokunxulumene neesekethe ze-RF, kwaye iphepha elilandelayo ligubungela izinto ezisebenzayo.
Ii-Capacitors
I-capacitor efanelekileyo ingabonelela ngokusebenza okufanayo kwisignali ye-1 Hz kunye nesignali ye-1 GHz. Kodwa izinto azikaze zibe ntle, kwaye izinto ezingezizo ezilungileyo ze-capacitor zinokuba zibaluleke kakhulu kwiifrikhwensi eziphezulu.
“C” ihambelana ne-capacitor efanelekileyo efihliweyo phakathi kwezinto ezininzi ezibangelwa yi-parasitic. Sinokumelana okungapheliyo phakathi kwee-plates (RD), ukumelana nochungechunge (RS), i-series inductance (LS), kunye ne-parallel capacitance (CP) phakathi kwee-PCB pads kunye ne-ground plane (sicinga ukuba izakhi ze-surface-mount; okungakumbi ngale nto kamva).
Eyona nto ibalulekileyo xa sisebenza ngemiqondiso ye-high-frequency yi-inductance. Silindele ukuba i-impedance ye-capacitor yehle ngokungapheliyo njengoko i-frequency isanda, kodwa ubukho be-parasitic inductance bubangela ukuba i-impedance yehle kwi-self-resonant frequency ize iqale ukwanda:
Abachasi, njl.
Kwanee-resistor zinokuba yingxaki kwiifrequensi eziphezulu, kuba zine-series inductance, i-parallel capacitance, kunye ne-capacitance eqhelekileyo enxulumene nee-PCB pads.
Kwaye oku kuphakamisa ingongoma ebalulekileyo: xa usebenza ngee-frequency eziphezulu, izinto zesekethe ye-parasitic zikho kuyo yonke indawo. Nokuba i-element ekhuselayo ilula okanye ifanelekile kangakanani na, isadinga ukupakishwa kwaye idityaniswe kwi-PCB, kwaye isiphumo si-parasitic. Oku kuyasebenza nakweyiphi na enye i-component: ukuba ipakishwe kwaye idityaniswe ebhodini, izinto ze-parasitic zikhona.
Iikristale
Eyona nto iphambili kwi-RF kukulawula imiqondiso ye-high-frequency ukuze idlulise ulwazi, kodwa ngaphambi kokuba silawule kufuneka senze. Njengakwezinye iintlobo zeesekethe, iikristale ziyindlela esisiseko yokwenza ireferensi ye-frequency ezinzileyo.
Nangona kunjalo, kuyilo lwedijithali kunye nolwesignali exutyiweyo, kudla ngokuba njalo ukuba iisekethe ezisekelwe kwikristale azifuni ngokuchanekileyo okunokubonelelwa yikristale, kwaye ngenxa yoko kulula ukungakhathali malunga nokukhethwa kwekristale. Isekethe yeRF, ngokuchaseneyo, inokuba neemfuno ezingqongqo zefrequency, kwaye oku kufuna kungekuphela nje ukuchaneka kwefrequency yokuqala kodwa kunye nokuzinza kwefrequency.
Ubuninzi be-oscillation yekristale eqhelekileyo bunovelwano kwiinguqu zobushushu. Ukungazinzi kwe-frequency okubangelwa yiyo kubangela iingxaki kwiinkqubo ze-RF, ingakumbi iinkqubo eziya kuvezwa kwiinguqu ezinkulu kubushushu obungqongileyo. Ngoko ke, inkqubo inokufuna i-TCXO, oko kukuthi, i-oscillator yekristale ehlawulelwayo kubushushu. Ezi zixhobo ziquka iisekethe ezihlawulela utshintsho lwe-frequency yekristale:
Ii-antenna
I-antenna yinxalenye engasebenziyo esetyenziselwa ukuguqula isignali yombane ye-RF ibe yimitha ye-electromagnetic radiation (EMR), okanye ngokuchaseneyo. Ngezinye izinto kunye nee-conductors sizama ukunciphisa iziphumo ze-EMR, kwaye ngee-antenna sizama ukuphucula ukuveliswa okanye ukwamkelwa kwe-EMR ngokubhekiselele kwiimfuno zesicelo.
Isayensi yee-antenna ayilula konke konke. Izinto ezahlukeneyo zichaphazela inkqubo yokukhetha okanye ukuyila i-antenna efanelekileyo kwisicelo esithile. I-AAC inamanqaku amabini (cofa apha napha) anika intshayelelo egqwesileyo kwiingcamango zee-antenna.
Iifrikhwensi eziphezulu zihamba nemingeni eyahlukeneyo yoyilo, nangona inxalenye ye-antenna yenkqubo inokuba yingxaki encinci njengoko iifrikhwensi zisanda, kuba iifrikhwensi eziphezulu zivumela ukusetyenziswa kwee-antenna ezimfutshane. Kule mihla kuqhelekile ukusebenzisa "i-antenna yetshiphu," ethengiswa kwi-PCB njengezinto eziqhelekileyo zokuxhoma kumphezulu, okanye i-antenna ye-PCB, eyenziwe ngokufaka umkhondo oyilwe ngokukodwa kuyilo lwe-PCB.
Isishwankathelo
Ezinye izinto zixhaphake kakhulu kwizicelo zeRF, kwaye ezinye kufuneka zikhethwe kwaye zisetyenziswe ngononophelo ngenxa yokuziphatha kwazo okungekho ngqiqweni kakhulu.
Izinto ezingasebenziyo zibonisa impendulo yefrikhwensi engeyiyo efanelekileyo ngenxa ye-parasitic inductance kunye ne-capacitance.
Usetyenziso lwe-RF lunokufuna iikristale ezichanekileyo ngakumbi kunye/okanye ezizinzileyo kuneekristale ezisetyenziswa rhoqo kwiisekethe zedijithali.
Ii-antenna zizinto ezibalulekileyo ekufuneka zikhethwe ngokweempawu kunye neemfuno zenkqubo ye-RF.
I-Si Chuan Keenlion Microwave iluhlu olukhulu kwiindlela ezinqamlezileyo kunye ne-broadband, igubungela amaza ukusuka kwi-0.5 ukuya kwi-50 GHz. Zenzelwe ukuphatha amandla okufaka ukusuka kwi-10 ukuya kwi-30 watts kwinkqubo yokudlulisela ye-50-ohm. Uyilo lwe-Microstrip okanye lwe-stripline luyasetyenziswa, kwaye lulungiselelwe ukusebenza kakuhle.
Ixesha lokuthumela: Novemba-03-2022
