Izixhumi ze-coaxial RF ziyizingxenye ezibalulekile zokudlulisa i-RF emkhakheni we-microwave futhi zisetshenziswa kakhulu kumadivayisi/izingxenye ezihlukahlukene ze-microwave, amathuluzi okuxhumana nama-microwave, amathuluzi namasistimu e-radar.
Izinhlobo zezixhumi ze-coaxial ze-RF: Ngokuthuthuka okusheshayo kokuxhumana okungenantambo kanye nobuchwepheshe be-radar eminyakeni yamuva nje, ukwanda kobubanzi bokudluliswa kwesistimu kudinga ukwanda kwamandla okudlulisa uhlelo. Njengengxenye yalo lonke uhlelo lwe-microwave, izixhumi ze-RF coaxial kufanele zikwazi ukumelana-nezidingo zokudlulisa amandla aphezulu. Onjiniyela be-RF bavamise ukwenza{3}ukuhlola amandla aphezulu kanye nokulinganisa, futhi amadivayisi ahlukahlukene e-microwave nezingxenye ezisetshenziselwa ukuhlola nawo adinga{4}amandla aphezulu. Lokhu kudala izimfuno ezikhulayo kumthamo wamandla ezixhumi ze-RF coaxial, inkomba eyinhloko yekhwalithi yesixhumi se-RF coaxial. Ngakho-ke, kungakanani okwaziyo ngomthamo wamandla wezixhumi ze-RF coaxial? Umthamo wamandla ezixhumi ze-RF coaxial yinkinga eyinkimbinkimbi, ethonywa izici eziningi, ezinye zazo ezisebenzisanayo. Lezi zici ngokuyinhloko zihlanganisa usayizi wesixhumi (okuhlanganisa nosayizi wephinifa), imvamisa yokusebenza, impahla yomzimba, izinto zokuvikela, ukuthembeka kokuxhumana, ukumelana nokuxhumana, isilinganiso se-voltage stand wave (VSWR), izinga lokushisa elizungezile, nokuphakama. Isibalo esingezansi sibonisa amanani wamandla anconyiwe we-Megaphase ezixhumi ezihlukene ze-RF kumaza ahlukene. Lapho uklama imikhiqizo ye-RF, ungakhetha isixhumi esifanele ngokusekelwe kubuningi bokusebenza komkhiqizo namandla okubamba amandla.
Okulandelayo, sizohlinzeka ngencazelo enemininingwane yezinto ezithonya umthamo wamandla ezixhumi ze-RF coaxial. Kumasiginali we-RF wefrikhwensi efanayo, izixhumi ezinkulu zinamandla okuphatha amandla aphezulu. Isibonelo, usayizi wephinikhodi yesixhumi uhlobene nomthamo wamanje wesixhumi, ohlobene ngokuqondile namandla. Phakathi kwezixhumi ezivame ukusetshenziswa ze-RF coaxial, 7/16 (DIN), 4.3-10, kanye-nezixhumi zohlobo lwe-N{8}}zinkulu ngokuqhathaniswa, ezihambisana namasayizi amaphinifa amakhulu. Ngokuvamile, amandla okubamba amandla{10}esixhumi sohlobo lwe-N cishe aphindwe kathathu noma kane kune-SMA. Lokhu kuduma okunyukile kwezixhumi zohlobo lwe-N{12}}kuchaza ukuthi kungani iningi lezinto ezingashintshiwe ezithengiswa emakethe, njengezixhumi nemithwalo enesilinganiso samandla esingaphezu kuka-200W, zisebenzisa{16}}izixhumi zohlobo. I-RFbuy (www.rfbuy.com) inikeza ukufinyelela okulula{42}ekulayishweni kwamandla aphezulu, izifinyezo, nezinye izingxenye ze-microwave ezingenzi lutho. Amandla okubamba amandla ezixhumi ze-RF coaxial ancipha ngokukhula kwemvamisa yesignali. Izinguquko kufrikhwensi yesignali yokudlulisa zithinta ngqo ukulahleka kokudluliselwa kanye nesilinganiso se-voltage stand wave (VSWR), okubuye kuthinte umthamo wamandla okudlulisela. Ngaphezu kwalokho, imiphumela yesikhumba nayo ingaba khona. Isibonelo, isixhumi esijwayelekile se-SMA sinamandla okubamba acishe abe ngu-500W ku-2GHz, kodwa amandla okubamba amandla amaphakathi angaphansi kuka-100W ku-18GHz. Ngokuya kwe-RFbuy RF Mall (www.rfbuy.com), izakhi eziningi ze-passive, njengezibambisi nemithwalo, ezisebenza kumafrikhwensi angaphezu kuka-18 GHz zinesilinganiso samandla esimaphakathi esingaphansi kuka-100 W. Kumaza amaza ama-millimeter, isifinyezo esingu-1.85mm 67 GHz esigxilile, sinamandla angaphansi kuka-5mm 7 W 7 W. Umthwalo we-GHz unesilinganiso samandla esimaphakathi esingaphansi kuka-22 W. Ukukhethwa okubanzi kwezixhumi ezingu-2.92mm kanye nemithwalo iyatholakala, ngezilinganiso zamandla ezimaphakathi ezifika ku-100 W. Izixhumi ze-RF ziklanywe ngobude obucacisiwe kagesi. Emugqeni wobude-onomkhawuko, lapho isici esivimbelayo kanye nokuthikamezeka komthwalo kungalingani, ingxenye ye-voltage kanye namandla asuka emlayishweni iboniswa emuva kumandla kagesi. Leli gagasi libizwa ngokuthi igagasi elibonisiwe, kuyilapho i-voltage kanye namandla asuka kugesi aya emthwalweni abizwa ngokuthi igagasi lesigameko. Igagasi elihlangene lesigameko namagagasi abonisiwe abizwa ngokuthi igagasi elimile. Isilinganiso samanani kagesi aphezulu kanye nobuncane begagasi elimile sibizwa ngokuthi i-voltage stand wave ratio (eyaziwa nangokuthi yi-stand wave wave). Amagagasi abonisiwe athatha umthamo wesiteshi, ehlisa umthamo wamandla okudlulisela. Ukulahlekelwa kokufakwayo (IL) kubhekisela ekulahlekeni kwamandla kulayini okubangelwa ukwethulwa kwesixhumi se-RF. Kuchazwa njengesilinganiso samandla aphumayo kumandla okufakwayo. Izinto eziningi zinomthelela ekulahlekeni kokufakwa kwesixhumi, okuhlanganisa ukungafani kokuphazamiseka kwesici, amaphutha wokunemba komhlangano, ukucaciswa kwesiphetho sokukhwelana{58}}kobuso, ukutsheka kwe-axis, i-lateral offset, i-eccentricity, ukunemba komshini, nokucwenga. Ukulahlekelwa kudala umehluko phakathi kwamandla okufaka nawokukhiphayo, okuphinde kuthinte ukuphatha kwamandla. Ukushintsha komfutho womoya endaweni ephakeme kubangela ukuhlukahluka kokungaguquki kwe-dielectric yamasegimenti omoya, futhi ezingcindezini eziphansi, umoya ungenwa kalula yi-ionization, ukhiqize i-corona. Ukuphakama kokuphakama kanye nokwehla komfutho womoya, amandla okubamba amandla aphansi. Ukumelana nokuxhumana: Ukumelana nokuxhumana kwesixhumi se-RF kubhekisela ekuphikiseni lapho kuxhunywana khona phakathi kwamakhondakta angaphakathi nangaphandle lapho isixhumi sihlanganiswa. Ngokuvamile kukalwa ngama-milliohms futhi kufanele igcinwe iphansi ngangokunokwenzeka. Ihlola ngokuyinhloko izakhiwo zemishini zabathintana nabo, futhi imiphumela yokumelana nobuningi kanye nokumelana okuhlangene kwe-solder kufanele kuqedwe ngesikhathi sokulinganisa. Ukumelana nokuxhumana kubangela ukushisa koxhumana nabo, okwenza kube nzima ukudlulisa amasiginali we-microwave wamandla aphezulu. Izinto zokuxhuma: Umthamo wokubamba amandla wesixhumi esifanayo ungahluka kuye ngezinto ezisetshenziswayo.