Ngaphandle kwesihlungi engxenyeni engaphambili ye-RF, umphumela wokwamukela uzoncishiswa kakhulu. Isaphulelo sikhulu kangakanani? Ngokuvamile, ngama-antenna amahle, ibanga lizoba libi okungenani izikhathi ezimbili. Futhi, uma i-antenna iphakeme, yilapho ukwamukela kuba kubi kakhulu! Kungani kunjalo? Ngoba isibhakabhaka sanamuhla sigcwele izimpawu eziningi, lezi zibonakaliso zivimba ithubhu yokwamukela yangaphambili. Njengoba isihlungi sangaphambili sibaluleke kangaka, ungasenza kanjani isihlungi sangaphambili? I-Rf ingcweti ephezulu embonini ukukufundisa! Kodwa-ke, isihlungi sangaphambili sebhendi ye-435MHz akulula ukusifaka. Ake siqale ukuhlaziya
Lena isethi yezihlungi ze-band-pass ze-Chebyshev ezine-capacitor coupling ephezulu kanye nemvamisa ephakathi engu-435MHz. Ngenxa yokusetshenziswa kwama-chip inductors atholakala kwezentengiselwano (anenani le-Q elifika ku-70), ukulahlekelwa kokufakwa kukhulu kakhulu, kufinyelela ku--11db, kanti enye ijika liwukubonakaliswa (okungaguqulwa kube amagagasi amile). Ngakho-ke, ukuzwela kwesamukeli kuthinteka kakhulu, ngoba ukuzwela kwesamukeli kuhlobene ngqo nesibalo somsindo sesigaba sokuqala sokukhulisa okuphezulu, noma ngabe ubuchwepheshe buhle, njengokuthi isibalo somsindo sokukhulisa okuphezulu singalawulwa sibe ngu-0.5, kodwa ukulahleka kwepulagi yesihlungi sangaphambili empeleni kuzokwandisa isibalo somsindo ngo-11db. Ngakho-ke akuvamile ukubona esinye sisetshenziswa kanje. Bheka lesi sithombe futhi:
Gcina amanye amapharamitha, i-inductor ithathelwa indawo yi-hollow coil engcono, yize ivolumu inkulu, kodwa ukulahlekelwa kokufakwa kuba cishe yi--5, okungasetshenziswa ngokuyisisekelo, kodwa kusenzima kakhulu ukuyenza. Ngoba: I-coupling capacitance ephezulu ingu-0.2P kuphela, futhi i-capacitance yalo mthamo akulula kakhulu ukuyithenga, ngakho-ke ungadonsa kuphela i-capacitor ku-PCB, okuletha ubunzima empumelelweni eyodwa. Ngisho ne-inductor engu-12nH ayilungile kakhulu ukuyiphendukisa, futhi kumele ibe yi-hollow futhi ihlangane, futhi akulungile ukuyilawula uma kungekho lwazi olwanele. I-inductance isenkulu kancane, amapharamitha alawo ma-capacitor azwela kakhulu, futhi ushintsho oluncane luzothinta ukusebenza. Ngakho-ke kuthiwani uma ungaqhubeka nokukhulisa inani le-Q le-inductor, futhi kukhona indlela yokuqhubeka nokunciphisa i-coupling capacitance? Bese unciphisa i-bandwidth kancane. Isimo sizoba kanje:
Inani le-inductance Q lalesi sibalo ngokuzumayo liba ngu-1600, kanti i-inductance nayo iba nkulu, igrafu iba yinhle kakhulu, lesi sihlungi singaqinisekisa ukukhetha nokuzwela kwesamukeli nezinye izinkomba, uma kungekho ukucatshangelwa kokusetshenziswa kwamandla ngqo ngemuva kwengxenye ye-IC, kungazelelwe donsela ibanga phezulu. Ukusebenza okungcono, kodwa usayizi yisihlungi se-microstrip esikhulu kakhulu
Umklamo wesihlungi esijikelezayo osebenzayo Kulesi sihlungi esijikelezayo, abantu abambalwa kakhulu abazoklama ngempela eShayina, futhi isofthiwe ingahlanganiswa kahle. Okokuqala, isithombe sangaphambilini sethula isihlungi sangempela esijikelezayo samadivayisi eselula angu-435MHz. Eqinisweni, izihlungi ezingcono kufanele zikhiqizwe ngomshini ngokuqinile, sizoklama izihlungi zekhwalithi ephezulu ze-2-cavity kanye ne-4-cavity zalo mshini wokuhlola.
Isikhathi sokuthunyelwe: Julayi-17-2024