Ungafinyelela kanjani ukufaniswa kwe-impedance kwama-waveguides?Kusuka kuthiyori yolayini wokudlulisa kuthiyori ye-antenna ye-microstrip, siyazi ukuthi uchungechunge olufanele noma imigqa yokudlulisela ehambisanayo ingakhethwa ukuze kuzuzwe ukufaniswa kwe-impedance phakathi kwemigqa yokudlulisela noma phakathi kwemigqa yokudlulisela kanye nemithwalo ukuze kuzuzwe ukudluliswa kwamandla okuphezulu kanye nokulahlekelwa okuncane kokuboniswa.Umgomo ofanayo wokufanisa i-impedance emigqeni ye-microstrip usebenza ekufanisweni kwe-impedance kuma-waveguides.Ukuboniswa kwezinhlelo ze-waveguide kungaholela ekungafaniseni kwe-impedance.Uma ukuwohloka kwe-impedance kwenzeka, isisombululo siyafana nemigqa yokudlulisela, okungukuthi, ukushintsha inani elidingekayo I-impedance ehlanganisiwe ibekwe ezindaweni ezibalwe ngaphambilini ku-waveguide ukuze kunqobe ukungafani, ngaleyo ndlela kuqedwe imiphumela yokucabangela.Ngenkathi imigqa yokudlulisela isebenzisa ama-impedances ane-lumped noma ama-stubs, ama-waveguides asebenzisa amabhulokhi ensimbi anomumo ohlukahlukene.
umfanekiso 1:I-Waveguide irises kanye nesekethe efanayo,(a)I-Capacitive;(b)i-inductive;(c)i-resonant.
Umfanekiso 1 ukhombisa izinhlobo ezahlukene zokumadanisa kwe-impedance, ukuthatha noma yimaphi amafomu abonisiwe futhi angaba namandla, asebenziseke kalula noma abe ne-resonant.Ukuhlaziywa kwezibalo kuyinkimbinkimbi, kodwa incazelo ebonakalayo ayikho.Uma kucatshangelwa umugqa wokuqala we-capacitive metal emfanekisweni, kungabonakala ukuthi amandla abekhona phakathi kwezindonga ezingaphezulu neziphansi ze-waveguide (kwimodi ebusayo) manje selikhona phakathi kwezindawo ezimbili zensimbi eziseduze, ngakho-ke amandla iphuzu liyakhula.Ngokuphambene, ibhulokhi yensimbi ku-Figure 1b ivumela okwamanje ukuthi igeleze lapho ingazange igeleze khona ngaphambili.Kuzoba nokugeleza kwamanje endizeni yensimu kagesi ethuthukisiwe ngaphambili ngenxa yokwengezwa kwebhulokhi yensimbi.Ngakho-ke, ukugcinwa kwamandla kwenzeka endaweni kazibuthe futhi inductance kulelo phuzu le-waveguide liyakhula.Ukwengeza, uma umumo nokuma kwendandatho yensimbi kuMfanekiso c kuklanywe ngokunengqondo, ukusabela kwe-inductive kanye nokusabela kwe-capacitive okwethulwa kuzolingana, futhi indawo yokuvula izoba yi-parallel resonance.Lokhu kusho ukuthi ukufaniswa kwe-impedance kanye nokulungisa imodi eyinhloko kuhle kakhulu, futhi umphumela wokuvimbela wale modi ngeke ubonakale.Nokho, ezinye izindlela noma amaza azoncishiswa, ngakho indandatho yensimbi ekhalayo isebenza njengesihlungi se-bandpass kanye nesihlungi semodi.
umfanekiso 2:(a)okuthunyelwe kwe-waveguide;(b)ukufanisa izikulufu ezimbili
Enye indlela yokushuna ikhonjisiwe ngenhla, lapho insimbi eyi-cylindrical post inweba isuka kolunye lwezinhlangothi ezibanzi iye ku-waveguide, ibe nomthelela ofanayo njengomucu wensimbi mayelana nokunikeza ukusabela okubambene ngaleso sikhathi.Iposi lensimbi ingaba namandla noma inductive, kuye ngokuthi inwebela kude kangakanani ku-waveguide.Ngokuyinhloko, le ndlela yokufanisa iwukuthi lapho insika yensimbi enjalo idlulela kancane ku-waveguide, inikeza i-capacitive susceptance ngaleso sikhathi, futhi i-capacitive susceptance iyanda kuze kube yilapho ukungena kucishe kube ingxenye yesine ye-wavelength, Kuleli phuzu, uchungechunge lwe-resonance luyenzeka. .Ukungena okwengeziwe kwesigxobo sensimbi kubangela ukuthi kube ne-inductive susceptance enciphayo njengoba ukufakwa kuba okuphelele.Ukuqina kwe-resonance ekufakweni kwephoyinti eliphakathi kuhambisana ngokuphambene nobubanzi bekholomu futhi kungasetshenziswa njengesihlungi, nokho, kulesi simo sisetshenziswa njengesihlungi sokumisa ibhande ukuze kudluliselwe izindlela zokuhleleka okuphezulu.Uma kuqhathaniswa nokwandisa i-impedance yemigqa yensimbi, inzuzo enkulu yokusebenzisa izigxobo zensimbi ukuthi kulula ukuyilungisa.Isibonelo, izikulufu ezimbili zingasetshenziswa njengamadivayisi wokushuna ukuze kuzuzwe ukufanisa okusebenzayo kwe-waveguide.
Imithwalo evimbelayo kanye nama-attenuators:
Njenganoma iyiphi enye isistimu yokudlulisa, ama-waveguides kwesinye isikhathi adinga ukufaniswa okuphelele kwe-impedance kanye nemithwalo eshuniwe ukuze imunce ngokuphelele amagagasi angenayo ngaphandle kokubonisa futhi angabi nazwelo kumafrikhwensi.Isicelo esisodwa samatheminali anjalo ukwenza izilinganiso zamandla ezahlukahlukene ohlelweni ngaphandle kokukhipha noma imaphi amandla.
umfanekiso 3 we-waveguide resistance load(a)i-taper eyodwa(b)i-double taper
Ukunqanyulwa kokumelana okuvame kakhulu ingxenye ye-dielectric elahlekile efakwe ekugcineni kwe-waveguide futhi i-tapered (nethiphu eqondiswe kumagagasi angenayo) ukuze ingabangeli ukuboniswa.Le ndlela elahlekile ingase ithathe bonke ububanzi be-waveguide, noma ingase ithathe kuphela indawo emaphakathi nesiphetho se-waveguide, njengoba kuboniswe kumfanekiso 3. I-taper ingaba i-taper eyodwa noma kabili futhi ngokuvamile inobude obungu-λp/2, ngobude obuphelele obucishe bube ngamaza amaza amabili.Ngokuvamile zenziwe ngamapuleti e-dielectric njengengilazi, ehlanganiswe nefilimu ye-carbon noma ingilazi yamanzi ngaphandle.Kuzinhlelo zokusebenza zamandla aphezulu, amatheminali anjalo angaba namasinki okushisa engezwe ngaphandle kwe-waveguide, futhi amandla alethwe kutheminali angahlakazwa kusinki wokushisa noma ngokupholiswa komoya okuphoqelelwe.
umfanekiso 4 I-vane attenuator ehambayo
Ama-attenuators e-Dielectric angenziwa akhipheke njengoba kuboniswe kuMfanekiso 4. Ibekwe phakathi nendawo ye-waveguide, ingahanjiswa eceleni ukusuka phakathi nendawo ye-waveguide, lapho izohlinzeka khona ukuncishiswa okukhulu kakhulu, emaphethelweni, lapho ukuncishiswa kuncipha kakhulu. njengoba amandla kagesi wemodi ebusayo aphansi kakhulu.
Ukunciphisa ku-waveguide:
Ukuncishiswa kwamandla kwamagagasi ikakhulukazi kufaka phakathi izici ezilandelayo:
1. Ukubonakaliswa okuvela ekunqanyulweni kwe-waveguide yangaphakathi noma izigaba ze-waveguide ezingaqondile
2. Ukulahlekelwa okubangelwa ukugeleza kwamanje ezindongeni ze-waveguide
3. Ukulahleka kwe-Dielectric kuma-waveguides agcwele
Okubili kokugcina kufana nokulahlekelwa okuhambisanayo emigqeni ye-coaxial futhi kokubili kuncane kakhulu.Lokhu kulahlekelwa kuncike odongeni kanye nobulukhuni bayo, i-dielectric esetshenzisiwe kanye nemvamisa (ngenxa yomphumela wesikhumba).Ngomzila wethusi, ububanzi busuka ku-4 dB/100m ku-5 GHz ukuya ku-12 dB/100m ku-10 GHz, kodwa ku-aluminium conduit, ububanzi buphansi.Kumagagasi enziwe ngesiliva, ukulahlekelwa kuvame ukuba ngu-8dB/100m ku-35 GHz, 30dB/100m ku-70 GHz, futhi kusondele ku-500 dB/100m ku-200 GHz.Ukuze kuncishiswe ukulahlekelwa, ikakhulukazi kumaza aphakeme kakhulu, amagagasi ngezinye izikhathi agqitshwa (ngaphakathi) ngegolide noma iplatinamu.
Njengoba sekushiwo, i-waveguide isebenza njengesihlungi sokudlula okuphezulu.Nakuba i-waveguide ngokwayo icishe ingalahleki, amaza angaphansi kwefrikhwensi yokusika ancishiswa kakhulu.Lokhu kuncishiswa kungenxa yokubonakala emlonyeni we-waveguide esikhundleni sokusakazeka.
Ukuhlanganisa i-Waveguide:
Ukuhlangana kwe-waveguide ngokuvamile kwenzeka ngama-flange lapho izingcezu ze-waveguide noma izingxenye zihlanganiswa ndawonye.Umsebenzi wale flange ukuqinisekisa ukuxhumana okushelelayo kwemishini kanye nezakhiwo zikagesi ezifanele, ikakhulukazi imisebe yangaphandle ephansi kanye nokubonakaliswa okuphansi kwangaphakathi.
I-Flange:
Ama-waveguide flange asetshenziswa kakhulu kwezokuxhumana nge-microwave, izinhlelo ze-radar, ukuxhumana ngesathelayithi, izinhlelo ze-antenna, kanye nemishini yaselabhorethri ocwaningweni lwesayensi.Zisetshenziselwa ukuxhuma izigaba ze-waveguide ezihlukene, ukuqinisekisa ukuthi ukuvuza nokuphazamiseka kuyavinjelwa, futhi kugcinwe ukuqondanisa okunembile kwe-waveguide ukuze kuqinisekiswe ukudluliswa okuphezulu Okunokwethenjelwa kanye nokuma okunembile kwamaza kagesi kagesi.I-waveguide ejwayelekile ine-flange ekugcineni ngakunye, njengoba kuboniswe kuMfanekiso 5.
umfanekiso 5 (a)i-flange;(b)ukuhlanganiswa kwe-flange.
Kumafrikhwensi aphansi i-flange izokwenziwa ibhrasi noma ishiselwe ku-waveguide, kuyilapho kumafrikhwensi aphezulu kusetshenziswa i-flange ye-butt flat.Lapho izingxenye ezimbili zihlanganiswa, ama-flange ahlanganiswa ndawonye, kodwa iziphetho kufanele ziqedwe kahle ukuze kugwenywe ukungaqhubeki ekuxhumekeni.Ngokusobala kulula ukuqondanisa izingxenye ngendlela efanele ngokunye ukulungiswa, ngakho-ke amagagasi amancane kwesinye isikhathi ahlonyiswe ngama-flange anentambo angahlanganiswa nenadi eliyindandatho.Njengoba imvamisa ikhula, usayizi wokuhlangana kwe-waveguide uyancipha ngokwemvelo, futhi ukungaqhubeki kokuhlanganisa kuba kukhulu ngokulingana nobude beza besignali nosayizi we-waveguide.Ngakho-ke, ukungaqhubeki kumafrikhwensi aphezulu kuba nzima kakhulu.
umfanekiso 6 (a)Ingxenye enqamulayo yokuhlangana kokuklinywa;(b)umbono wokugcina wokuminyanisa
Ukuze kuxazululwe le nkinga, igebe elincane lingashiywa phakathi kwamagagasi, njengoba kukhonjisiwe kuMfanekiso 6. Ukuhlanganisa okuklinyiwe okuhlanganisa i-flange evamile kanye ne-flange yokuminyanisa exhunywe ndawonye.Ukunxephezela ukungaqhubeki okungase kube khona, indandatho yokuklinywa eyindilinga ene-cross-section emise okwe-L isetshenziswa ku-choke flange ukuze kufinyelelwe ukuxhumana okuqinile.Ngokungafani nama-flange ajwayelekile, ama-coke flange azwela imvamisa, kepha idizayini eyenziwe kahle ingaqinisekisa umkhawulokudonsa onengqondo (mhlawumbe u-10% wemvamisa yesikhungo) lapho i-SWR ingeqi ku-1.05.
Isikhathi sokuthumela: Jan-15-2024
