Yadda za a cimma impedance matching na waveguides?Daga ka'idar layin watsawa a cikin ka'idar eriya ta microstrip, mun san cewa za'a iya zaɓar jerin da suka dace ko layin watsawa na layi ɗaya don cimma daidaituwa tsakanin layin watsawa ko tsakanin layin watsawa da lodi don cimma matsakaicin watsa wutar lantarki da ƙarancin tunani.Irin wannan ka'ida na matching impedance a cikin layin microstrip ya shafi matching impedance a cikin waveguides.Tunani a cikin tsarin waveguide na iya haifar da rashin daidaituwa na impedance.Lokacin da lalacewar impedance ya faru, maganin yana daidai da na layin watsawa, wato, canza ƙimar da ake buƙata Ana sanya impedance a cikin wuraren da aka riga aka ƙidaya a cikin waveguide don shawo kan rashin daidaituwa, ta haka ne ya kawar da tasirin tunani.Yayin da layukan watsawa ke amfani da dunkulewar magudanan ruwa ko stubs, masu amfani da igiyar ruwa suna amfani da tubalan karfe na siffofi daban-daban.
adadi 1: Waveguide irises da daidai da'ira, (a) Capacitive; (b) inductive; (c) resonant.
Hoto na 1 yana nuna nau'ikan nau'ikan daidaitawa daban-daban, ɗaukar kowane nau'ikan da aka nuna kuma yana iya zama mai ƙarfi, haɓaka ko haɓakawa.Binciken lissafi yana da rikitarwa, amma bayanin jiki ba haka bane.Idan akai la'akari da na farko capacitive karfe tsiri a cikin adadi, za a iya gani cewa m cewa wanzu tsakanin saman da kasa ganuwar na waveguide (a cikin rinjaye yanayin) yanzu ya wanzu tsakanin biyu karfe saman a kusanci, don haka da capacitance ne The batu yana ƙaruwa.Sabanin haka, shingen ƙarfe a cikin Hoto 1b yana ba da damar halin yanzu don gudana a inda baya gudana a da.Za a samu kwararar ruwa a cikin jirgin da aka inganta a baya saboda kara toshe karfen.Sabili da haka, ajiyar makamashi yana faruwa a cikin filin maganadisu kuma inductance a wancan batu na waveguide yana ƙaruwa.Bugu da kari, idan siffar da matsayi na karfe zobe a Figure c aka tsara da hankali, da inductive reactance da capacitive reactance gabatar zai zama daidai, da budewa zai zama a layi daya resonance.Wannan yana nufin cewa daidaitawar impedance da daidaitawa na babban yanayin yana da kyau sosai, kuma tasirin shunting na wannan yanayin zai zama mara kyau.Duk da haka, za a rage wasu hanyoyi ko mitoci, don haka zoben ƙarfe mai resonant yana aiki azaman matatar bandpass da matatar yanayi.
adadi 2: (a) waveguide posts; (b) madaidaicin dunƙule biyu
Ana nuna wata hanyar tune a sama, inda madaidaicin ƙarfe na silindical ya shimfiɗa daga ɗaya daga cikin faffadan ɓangarorin zuwa cikin waveguide, yana da tasiri iri ɗaya da tsiri na ƙarfe dangane da samar da amsa mai ruɗi a wannan lokacin.Rubutun ƙarfe na iya zama mai ƙarfi ko inductive, ya danganta da nisa zuwa ga jagorar wave.Ainihin, wannan hanyar da ta dace da ita ita ce lokacin da irin wannan ginshiƙi na ƙarfe ya ɗan ƙara ɗan ƙara kaɗan zuwa cikin waveguide, yana ba da damar haɓakawa a wannan lokacin, kuma ƙarfin ƙarfin ƙarfin yana ƙaruwa har sai shigar ya kai kusan kwata na tsawon zango, A wannan lokacin, jerin resonance yana faruwa. .Ci gaba da shiga cikin post ɗin ƙarfe yana haifar da rashin lafiyar da aka samar wanda ke raguwa yayin da shigar ya zama cikakke.Ƙarfin faɗakarwa a wurin shigarwa na tsakiya ya bambanta da diamita na ginshiƙi kuma ana iya amfani dashi azaman tacewa, duk da haka, a wannan yanayin ana amfani dashi azaman matattarar tasha don watsa yanayin tsari mafi girma.Idan aka kwatanta da haɓaka ƙwanƙwasawa na ƙwanƙwasa ƙarfe, babban fa'idar yin amfani da saƙon ƙarfe shine cewa suna da sauƙin daidaitawa.Misali, ana iya amfani da sukurori biyu azaman na'urorin daidaitawa don cimma ingantacciyar madaidaicin jagorar igiyar ruwa.
Nauyi masu juriya da attenuators:
Kamar kowane tsarin watsawa, waveguides wani lokacin yana buƙatar cikakkiyar madaidaicin impedance da kuma kayan aikin da aka gyara don ɗaukar raƙuman ruwa mai shigowa gabaɗaya ba tare da tunani ba kuma don zama marasa hankali.Ɗaya daga cikin aikace-aikacen irin waɗannan tashoshi shine yin ma'aunin wuta daban-daban akan tsarin ba tare da haskaka kowane wuta ba.
adadi 3 nauyin juriya na waveguide (a) taper guda ɗaya (b) taper biyu
Mafi yawan ƙarewar juriya na yau da kullun shine sashe na dielectric mai asarar da aka sanya a ƙarshen jagorar igiyar ruwa kuma an ɗora shi (tare da tip ɗin da aka nuna ga igiyar ruwa mai shigowa) don kada ya haifar da tunani.Wannan matsakaicin hasara na iya ɗaukar duk faɗin jagorar waveguide, ko kuma yana iya mamaye tsakiyar ƙarshen jagorar raƙuman ruwa, kamar yadda aka nuna a cikin Hoto 3. Taper na iya zama guda ɗaya ko taper biyu kuma yawanci yana da tsayin λp/2, tare da jimlar tsawon kusan zango biyu.Yawancin lokaci ana yin su da faranti na dielectric kamar gilashi, mai rufi da fim ɗin carbon ko gilashin ruwa a waje.Don aikace-aikace masu ƙarfi, irin waɗannan tashoshi na iya samun ɗumbin zafin rana da aka ƙara a waje da waveguide, kuma ikon da aka bayar zuwa tashar za a iya bazuwa ta wurin dumama zafi ko ta hanyar sanyaya iska mai ƙarfi.
adadi 4 Movable vane attenuator
Dielectric attenuators za a iya cirewa kamar yadda aka nuna a cikin Hoto na 4. An sanya shi a tsakiyar tsakiyar raƙuman ruwa, ana iya motsa shi a gefe daga tsakiyar waveguide, inda zai samar da mafi girma attenuation, zuwa gefuna, inda attenuation ya ragu sosai. tun da ƙarfin filin lantarki na yanayin rinjaye ya fi ƙasa da ƙasa.
Attenuation a cikin waveguide:
Ƙaddamar da makamashi na waveguides ya ƙunshi abubuwa masu zuwa:
1. Tunani daga katsewar jagorar waveguide na ciki ko sassan jagorar raƙuman ruwa mara kyau.
2. Asarar da ke gudana a cikin bangon waveguide na yanzu
3. Dielectric hasara a cika waveguides
Biyu na ƙarshe sun yi kama da daidaitattun hasara a cikin layin coaxial kuma dukkansu ƙananan ƙananan ne.Wannan asarar ya dogara da kayan bango da rashin ƙarfi, dielectric da aka yi amfani da shi da kuma mita (saboda tasirin fata).Don magudanar tagulla, kewayon yana daga 4 dB/100m a 5 GHz zuwa 12 dB/100m a 10 GHz, amma ga bututun aluminum, kewayon ya ragu.Don jagororin igiyar ruwa mai rufin azurfa, asarar yawanci 8dB/100m a 35 GHz, 30dB/100m a 70 GHz, kuma kusa da 500 dB/100m a 200 GHz.Don rage hasara, musamman ma a mafi girman mitoci, wasu lokuta ana liƙa waveguides (ciki) da zinariya ko platinum.
Kamar yadda aka riga aka nuna, waveguide yana aiki azaman matattarar wuce gona da iri.Ko da yake jagorar igiyar ruwa ita kanta ba ta da asara, mitocin da ke ƙasa da mitar yankewa suna raguwa sosai.Wannan attenuation ya faru ne saboda tunani a bakin waveguide maimakon yaduwa.
Haɗin kai waveguide:
Haɗin kai na waveguide yawanci yana faruwa ta hanyar flanges lokacin da aka haɗa guda ko abubuwan haɗin kai tare.Ayyukan wannan flange shine tabbatar da haɗin injiniya mai santsi da kayan lantarki masu dacewa, musamman ƙananan radiation na waje da ƙananan tunani na ciki.
Flange:
Ana amfani da flanges na Waveguide sosai a cikin sadarwar microwave, tsarin radar, sadarwar tauraron dan adam, tsarin eriya, da kayan aikin dakin gwaje-gwaje a cikin binciken kimiyya.Ana amfani da su don haɗa sassan jagorar igiyoyi daban-daban, tabbatar da hana ɗigogi da tsangwama, da kiyaye daidaitaccen jeri na jagorar igiyar ruwa don tabbatar da babban abin dogaro mai ƙarfi da daidaitaccen matsayi na mitar igiyoyin lantarki.Jagorar raƙuman ruwa na yau da kullun yana da flange a kowane ƙarshen, kamar yadda aka nuna a hoto na 5.
adadi na 5 (a) flange na fili; (b) hada-hadar flange.
A ƙananan mitoci za a yi amfani da flange ko welded zuwa ga waveguide, yayin da a mafi girma mitoci ana amfani da flange lebur mai laushi.Lokacin da aka haɗa ɓangarori biyu, ana kulle ɓangarorin tare, amma dole ne a gama ƙarshen su lami lafiya don guje wa yankewa a haɗin.Babu shakka yana da sauƙi don daidaita abubuwan da aka gyara daidai tare da wasu gyare-gyare, don haka ƙananan raƙuman ruwa a wasu lokuta ana sanye su da filaye masu zare waɗanda za a iya haɗa su tare da zobe na goro.Yayin da mitar ke ƙaruwa, girman haɗin gwiwar igiyar igiyar ruwa yana raguwa a zahiri, kuma dakatarwar haɗin gwiwar ya zama mafi girma daidai da tsayin sigina da girman jagorar igiyar ruwa.Don haka, katsewa a mitoci mafi girma suna zama da wahala.
adadi na 6 (a) Ketare sashin haɗin gwiwar shake; (b) kallon ƙarshen shake flange
Don magance wannan matsala, za a iya barin ƙaramin tazara tsakanin magudanar igiyar ruwa, kamar yadda aka nuna a hoto na 6. Haɗin haɗaɗɗiyar shaƙewa wanda ya ƙunshi flange na yau da kullun da flange na shake da aka haɗa tare.Don rama yiwuwar yankewa, ana amfani da zoben shaƙa mai madauwari tare da sashin giciye mai siffa L a cikin flange na shaƙa don cimma haɗin da ya dace.Ba kamar flanges na yau da kullun ba, flanges na shaƙa suna da hankali, amma ingantaccen ƙira na iya tabbatar da ingantaccen bandwidth (watakila 10% na mitar cibiyar) wanda SWR bai wuce 1.05 ba.
Lokacin aikawa: Janairu-15-2024
