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Amacandelo ePassive kwiiSekethe zeRF 

I-Resistors, i-capacitors, i-Antennas. . . . Funda malunga namalungu okwenziwa asetyenziswa kwiinkqubo zeRF.

Iinkqubo zeRF azahlukanga kakhulu kwezinye iindidi zeesekethe zombane. Kusebenza imithetho efanayo yefiziksi, kwaye ngenxa yoko amacandelo asisiseko asetyenziswa kuyilo lweRF akwafumaneka kwiisekethe zedijithali kunye neesekethe ze-analog ezisezantsi.

Nangona kunjalo, uyilo lweRF lubandakanya uluhlu olulodwa lwemingeni kunye neenjongo, kwaye ngenxa yoko iimpawu kunye nokusetyenziswa kwamacandelo kufuna ingqalelo ekhethekileyo xa sisebenza kwimeko yeRF. Kwakhona, ezinye iisekethe ezidityanisiweyo zenza umsebenzi othe ngqo kakhulu kwiinkqubo ze-RF—azisetyenziswa kwiisekethe zefrikhwensi ephantsi kwaye zinokuqondwa kakuhle ngabo banamava amancinane ngobuchule bokuyila beRF.

Sihlala sihlela amacandelo asebenzayo okanye asebenzayo, kwaye le ndlela isemthethweni ngokulinganayo kummandla weRF. Iindaba zixoxa ngamacandelo angenziwayo ngokukodwa ngokunxulumene neesekethe zeRF, kwaye iphepha elilandelayo liquka izinto ezisebenzayo.

IiCapacitors

I-capacitor efanelekileyo iya kubonelela ngokusebenza okufanayo kwisignali ye-1 Hz kunye nesignali ye-1 GHz. Kodwa izinto azizange zilunge, kwaye izinto ezingezizo ezo ze-capacitor zinokubaluleke kakhulu kumaza aphezulu.

"C" ihambelana ne-capacitor efanelekileyo engcwatywe phakathi kwezinto ezininzi ze-parasitic. Sinokumelana okungapheliyo phakathi kweepleyiti (i-RD), ukuxhathisa uchungechunge (RS), i-series inductance (LS), kunye ne-parallel capacitance (CP) phakathi kweepadi ze-PCB kunye nenqwelomoya ephantsi (sithatha amacandelo aphezu komhlaba; ngaphezulu koku kamva).

Eyona nto ibalulekileyo yokungafanelanga xa sisebenza ngeempawu ezixhaphake kakhulu kukunyanzeliswa. Silindele ukuba i-impedance ye-capacitor yehle ngokungapheliyo njengoko inyuka rhoqo, kodwa ubukho be-parasitic inductance kubangela ukuba i-impedance ihle phantsi kwi-self-resonant frequency emva koko iqale ukunyuka:

Abachasi, et al.

Nditsho nabaxhathisi banokuba yingxaki kumaza aphezulu, kuba bane-series inductance, i-parallel capacitance, kunye ne-capacitance eqhelekileyo ehambelana neepads zePCB.

Kwaye oku kuzisa inqaku elibalulekileyo: xa usebenza ngee-frequencies eziphezulu, izinto zesekethe yeparasitic zikuyo yonke indawo. Nokuba ilula kangakanani okanye ilungile kangakanani into echasayo, isafuna ukupakishwa kwaye ithengiswe kwi-PCB, kwaye isiphumo ziiparasitics. Kukwasebenza okufanayo nakweliphi na elinye icandelo: ukuba ipakishwe kwaye ithengiswe ebhodini, izinto zeparasitic zikhona.

Iikristale

Undoqo weRF kukulawula imiqondiso yefrikhwensi ephezulu ukuze idlulise ulwazi, kodwa ngaphambi kokuba siqhathe kufuneka sivelise. Njengakwezinye iindidi zeesekethe, iikristale ziyindlela esisiseko yokuvelisa ireferensi ezinzileyo.

Nangona kunjalo, kuyilo lwedijithali kunye nomxube wesignali, ihlala iyimeko yokuba iisekethe ezisekwe kwikristale ngokwenene azifuni ukuchaneka ukuba ikristale inokubonelela, kwaye ngenxa yoko kulula ukungakhathali malunga nokukhethwa kwekristale. Isekethe ye-RF, ngokuchaseneyo, inokuba neemfuneko ezingqongqo zamaza, kwaye oku kufuna kungekuphela nje ukuchaneka kokuqala kodwa kunye nokuzinza kwamaza.

I-oscillation frequency ye-crystal eqhelekileyo inovakalelo kuguquko lobushushu. Isiphumo sokungazinzi rhoqo kudala iingxaki kwiisistim zeRF, ngakumbi iisistim eziya kuchanabeka kumaqondo amakhulu obushushu. Ngaloo ndlela, inkqubo inokufuna i-TCXO, oko kukuthi, i-crystal oscillator ye-crystal oscillator. Ezi zixhobo zibandakanya ukujikeleza okuhlawulela ukwahluka kwamaxesha ekristale:

Iimpondo

I-eriyali licandelo elisetyenziswayo ukuguqula isignali yombane yeRF ibe yimitha yombane yombane (EMR), okanye ngokuphendululekileyo. Ngamanye amacandelo kunye nabaqhubi sizama ukunciphisa imiphumo ye-EMR, kwaye kunye neentenna sizama ukunyusa isizukulwana okanye ukufumana i-EMR ngokubhekiselele kwiimfuno zesicelo.

Isayensi ye-antenna ayikho lula. Izinto ezahlukeneyo zinefuthe kwinkqubo yokukhetha okanye ukuyila i-eriyali eyiyeyona ifanelekileyo kwisicelo esithile. I-AAC inamanqaku amabini (cofa apha kwaye apha) abonelela ngentshayelelo egqwesileyo kwiikhonsepthi ze-eriyali.

Iifrikhwensi eziphezulu zikhatshwa yimiceli mngeni yoyilo eyahluka-hlukeneyo, nangona inxalenye ye-eriyali yenkqubo inokuba yingxaki encinci njengoko i-frequency inyuka, kuba amaza aphezulu avumela ukusetyenziswa kwee-eriyali ezimfutshane. Kule mihla kuqhelekile ukusebenzisa nokuba "i-antenna ye-chip," ethi ithengiswe kwi-PCB njengezinto eziqhelekileyo zokunyuka komphezulu, okanye i-eriyali ye-PCB, eyilwa ngokubandakanya umkhondo oyilwe ngokukodwa kuyilo lwe-PCB.

Isishwankathelo

Amanye amacandelo axhaphake kuphela kwizicelo zeRF, kwaye amanye kufuneka akhethwe kwaye aphunyezwe ngononophelo ngakumbi ngenxa yokuziphatha kwawo okungaqhelekanga kokusebenza okuphezulu.

Amacandelo e-Passive abonisa impendulo yefrikhwensi engafanelekanga ngenxa ye-parasitic inductance kunye ne-capacitance.

Usetyenziso lweRF lusenokufuna iikristale ezichaneke ngakumbi kunye/okanye ezizinzileyo kuneekristale ezidla ngokusetyenziswa kwiisekethe zedijithali.

Ii-eriyali zizinto ezibalulekileyo ekufuneka zikhethwe ngokweempawu neemfuno zenkqubo yeRF.

Si Chuan Keenlion Microwave ukhetho olukhulu kwi-narrowband kunye noqwalaselo lwebroadband, egubungela amaza ukusuka kwi-0.5 ukuya kwi-50 GHz. Zenzelwe ukuphatha ukusuka kwi-10 ukuya kwi-30 igalelo lamandla kwi-50-ohm inkqubo yokuhambisa. Uyilo lweMicrostrip okanye lwestripline luyasetyenziswa, kwaye lulungiselelwe ukusebenza kakuhle.

Sisenokwenza ngokwezifiso amalungu e-rf passive ngokweemfuno zakho. Ungangenisa iphepha lokulungiselela ukubonelela ngeenkcukacha ozifunayo.