Mitar sigina a aikace-aikacen radar mota ya bambanta tsakanin 30 zuwa 300 GHz, ko da ƙasa da 24 GHz.Tare da taimakon ayyuka daban-daban na kewayawa, ana watsa waɗannan sigina ta hanyar fasahohin layin watsawa daban-daban kamar layin microstrip, layin tsiri, haɗe-haɗen waveguide (SIW) da kuma tushen coplanar waveguide (GCPW).Waɗannan fasahohin layin watsawa (Fig. 1) galibi ana amfani da su a mitoci na microwave, wani lokacin kuma a mitocin igiyar ruwa na millimita.Ana buƙatar kayan laminate na kewaye da aka yi amfani da su musamman don wannan babban yanayin mitar.Layin Microstrip, a matsayin mafi sauƙi kuma mafi yawan amfani da fasahar kewaya layin watsawa, na iya cimma ƙimar cancantar kewayawa ta amfani da fasahar sarrafa kewaye ta al'ada.Amma lokacin da aka ɗaga mitar zuwa mitar kalaman milimita, maiyuwa ba zai zama mafi kyawun layin watsawa ba.Kowane layin watsa yana da nasa amfani da rashin amfani.Misali, ko da yake layin microstrip yana da sauƙin sarrafawa, dole ne ya magance matsalar babban hasara na radiation lokacin amfani da mitar kalaman millimeter.
Hoto 1 Lokacin canzawa zuwa mitar kalaman milimita, masu zanen injin microwave suna buƙatar fuskantar zaɓi na aƙalla fasahar layin watsawa huɗu a mitar microwave.
Ko da yake buɗe tsarin layin microstrip ya dace don haɗin jiki, zai kuma haifar da wasu matsaloli a mitoci mafi girma.A cikin layin watsa microstrip, taguwar ruwa na lantarki (EM) suna yaduwa ta hanyar madugu na kayan da'ira da ma'aunin wutar lantarki, amma wasu igiyoyin lantarki suna yaduwa ta cikin iskan da ke kewaye.Saboda ƙarancin darajar Dk na iska, ƙimar Dk mai tasiri na kewaye yana ƙasa da na kayan kewayawa, wanda dole ne a yi la'akari da shi a cikin simulation.Idan aka kwatanta da ƙananan Dk, da'irori da aka yi da manyan kayan Dk suna hana watsa igiyoyin lantarki da rage yawan yaɗuwar.Don haka, ana amfani da ƙananan kayan da'ira na Dk a cikin da'irar igiyar ruwa ta millimita.
Saboda akwai takamaiman matakin makamashi na lantarki a cikin iska, layin layin microstrip zai haskaka waje cikin iska, kama da eriya.Wannan zai haifar da asarar hasken da ba dole ba ga layin layin microstrip, kuma asarar za ta karu tare da karuwar mita, wanda kuma ya kawo kalubale ga masu zanen da'irar da ke nazarin layin microstrip don iyakance asarar radiation kewaye.Domin rage asarar hasara, ana iya ƙirƙira layin microstrip tare da kayan kewayawa tare da ƙimar Dk mafi girma.Koyaya, haɓakar Dk zai rage saurin yaɗuwar igiyoyin lantarki (dangane da iska), yana haifar da canjin yanayin sigina.Wata hanya kuma ita ce rage hasarar radiation ta amfani da kayan da'ira mafi sira don aiwatar da layin microstrip.Koyaya, idan aka kwatanta da kayan da'irar masu kauri, kayan da'ira masu sirara sun fi saurin kamuwa da tasirin tarkacen bangon bangon jan karfe, wanda kuma zai haifar da ƙayyadaddun lokaci na sigina.
Kodayake daidaitawar da'irar layin microstrip abu ne mai sauƙi, da'irar layin microstrip a cikin bandeji na millimeter yana buƙatar daidaitaccen kulawar haƙuri.Misali, faɗin madugu wanda ke buƙatar kulawa sosai, kuma mafi girman mitar, mafi tsananin haƙuri zai kasance.Sabili da haka, layin microstrip a cikin mitar mitar raƙuman ruwa na millimeter yana da matukar damuwa ga canjin fasahar sarrafawa, da kauri na dielectric abu da jan ƙarfe a cikin kayan, da buƙatun haƙuri don girman kewaye da ake buƙata suna da tsauri.
Stripline ingantaccen fasahar layin watsawa ce, wanda zai iya taka rawa mai kyau a mitar kalaman millimeter.Koyaya, idan aka kwatanta da layin microstrip, mai jagorar tsiri yana kewaye da matsakaici, don haka ba shi da sauƙi haɗa haɗin haɗin ko wasu tashoshin shigarwa/fitarwa zuwa layin sigina don watsa sigina.Za a iya ɗaukar tsiri a matsayin nau'in kebul na coaxial mai lebur, wanda aka nannade madubin ta hanyar dielectric Layer sannan kuma an rufe shi da stratum.Wannan tsarin zai iya samar da tasirin keɓewar kewayawa mai inganci, yayin da yake kiyaye yaduwar siginar a cikin kayan kewayawa (maimakon a cikin iska mai kewaye).Kalaman lantarki ko da yaushe yana yaduwa ta cikin kayan kewayawa.Za a iya siffanta da'irar tsiri bisa ga halaye na kayan da'irar, ba tare da la'akari da tasirin igiyoyin lantarki a cikin iska ba.Duk da haka, na'urar da'irar da ke kewaye da matsakaici tana da rauni ga canje-canje a cikin fasahar sarrafawa, kuma ƙalubalen ciyar da sigina ya sa ya zama da wahala ga igiyar igiya ta jurewa, musamman ma a ƙarƙashin yanayin ƙarami mai girma a mita mita.Don haka, ban da wasu da'irori da ake amfani da su a cikin radars na motoci, yawanci ba a amfani da layin tsiri a cikin da'irar igiyar ruwa ta millimita.
Saboda akwai takamaiman matakin makamashi na lantarki a cikin iska, layin layin microstrip zai haskaka waje cikin iska, kama da eriya.Wannan zai haifar da asarar hasken da ba dole ba ga layin layin microstrip, kuma asarar za ta karu tare da karuwar mita, wanda kuma ya kawo kalubale ga masu zanen da'irar da ke nazarin layin microstrip don iyakance asarar radiation kewaye.Domin rage asarar hasara, ana iya ƙirƙira layin microstrip tare da kayan kewayawa tare da ƙimar Dk mafi girma.Koyaya, haɓakar Dk zai rage saurin yaɗuwar igiyoyin lantarki (dangane da iska), yana haifar da canjin yanayin sigina.Wata hanya kuma ita ce rage hasarar radiation ta amfani da kayan da'ira mafi sira don aiwatar da layin microstrip.Koyaya, idan aka kwatanta da kayan da'irar masu kauri, kayan da'ira masu sirara sun fi saurin kamuwa da tasirin tarkacen bangon bangon jan karfe, wanda kuma zai haifar da ƙayyadaddun lokaci na sigina.
Kodayake daidaitawar da'irar layin microstrip abu ne mai sauƙi, da'irar layin microstrip a cikin bandeji na millimeter yana buƙatar daidaitaccen kulawar haƙuri.Misali, faɗin madugu wanda ke buƙatar kulawa sosai, kuma mafi girman mitar, mafi tsananin haƙuri zai kasance.Sabili da haka, layin microstrip a cikin mitar mitar raƙuman ruwa na millimeter yana da matukar damuwa ga canjin fasahar sarrafawa, da kauri na dielectric abu da jan ƙarfe a cikin kayan, da buƙatun haƙuri don girman kewaye da ake buƙata suna da tsauri.
Stripline ingantaccen fasahar layin watsawa ce, wanda zai iya taka rawa mai kyau a mitar kalaman millimeter.Koyaya, idan aka kwatanta da layin microstrip, mai jagorar tsiri yana kewaye da matsakaici, don haka ba shi da sauƙi haɗa haɗin haɗin ko wasu tashoshin shigarwa/fitarwa zuwa layin sigina don watsa sigina.Za a iya ɗaukar tsiri a matsayin nau'in kebul na coaxial mai lebur, wanda aka nannade madubin ta hanyar dielectric Layer sannan kuma an rufe shi da stratum.Wannan tsarin zai iya samar da tasirin keɓewar kewayawa mai inganci, yayin da yake kiyaye yaduwar siginar a cikin kayan kewayawa (maimakon a cikin iska mai kewaye).Kalaman lantarki ko da yaushe yana yaduwa ta cikin kayan kewayawa.Za a iya siffanta da'irar tsiri bisa ga halaye na kayan da'irar, ba tare da la'akari da tasirin igiyoyin lantarki a cikin iska ba.Duk da haka, na'urar da'irar da ke kewaye da matsakaici tana da rauni ga canje-canje a cikin fasahar sarrafawa, kuma ƙalubalen ciyar da sigina ya sa ya zama da wahala ga igiyar igiya ta jurewa, musamman ma a ƙarƙashin yanayin ƙarami mai girma a mita mita.Don haka, ban da wasu da'irori da ake amfani da su a cikin radars na motoci, yawanci ba a amfani da layin tsiri a cikin da'irar igiyar ruwa ta millimita.
Hoto 2 Zane da kwaikwaya na mai kula da kewaye na GCPW yana da rectangular (sama da adadi), amma ana sarrafa mai gudanarwa zuwa trapezoid (a ƙasa adadi), wanda zai sami tasiri daban-daban akan mitar kalaman millimeter.
Don yawancin aikace-aikacen da'irar igiyar igiyar milimita masu tasowa waɗanda ke kula da martanin sigina (kamar radar mota), ya kamata a rage abubuwan da ke haifar da rashin daidaituwar lokaci.Mitar mitar mitoci GCPW kewaye tana da rauni ga canje-canje a cikin kayan aiki da fasahar sarrafawa, gami da canje-canje a ƙimar Dk abu da kauri.Abu na biyu, aikin da'ira na iya shafar kaurin madubin jan karfe da tarkacen bangon tagulla.Saboda haka, ya kamata a kiyaye kauri na madubin jan ƙarfe a cikin tsananin haƙuri, kuma a rage girman girman murfin jan karfe.Abu na uku, zaɓin rufin saman da'irar GCPW na iya shafar aikin igiyar milimita.Misali, da'irar da ke amfani da zinari na nickel na sinadari yana da asarar nickel fiye da jan karfe, kuma layin nickel plated zai ƙara asarar GCPW ko layin microstrip (Hoto na 3).A ƙarshe, saboda ƙananan tsayin raƙuman ruwa, canjin murfin kauri kuma zai haifar da canjin amsawar lokaci, kuma tasirin GCPW ya fi na layin microstrip.
Hoto 3 Layin microstrip da da'irar GCPW da aka nuna a cikin adadi suna amfani da kayan kewayawa iri ɗaya (Rogers' 8mil kauri RO4003C ™ Laminate), tasirin ENIG akan kewayen GCPW ya fi na layin microstrip a mitar kalaman millimeter.
Lokacin aikawa: Oktoba-05-2022
