Nkhani - Kusintha kwa mphamvu mu ma antenna a radar

Mu ma circuit kapena machitidwe a microwave, dera lonse kapena makina nthawi zambiri amakhala ndi zida zambiri zoyambira za microwave monga zosefera, zolumikizira, zogawa mphamvu, ndi zina zotero. Tikukhulupirira kuti kudzera mu zida izi, ndizotheka kutumiza mphamvu ya chizindikiro kuchokera pamalo amodzi kupita kwina popanda kutayika kwakukulu;

Mu dongosolo lonse la radar ya galimoto, kusintha kwa mphamvu kumaphatikizapo kusamutsa mphamvu kuchokera ku chip kupita ku chodyetsa pa bolodi la PCB, kusamutsa chodyetsa kupita ku thupi la antenna, komanso kuwala kwa mphamvu kogwira mtima ndi antenna. Mu njira yonse yosamutsa mphamvu, gawo lofunika kwambiri ndi kapangidwe ka chosinthira. Zosinthira mu machitidwe a mafunde a millimeter makamaka zimaphatikizapo kusintha kwa microstrip kupita ku substrate integrated waveguide (SIW), kusintha kwa microstrip kupita ku waveguide, kusintha kwa SIW kupita ku waveguide, kusintha kwa coaxial kupita ku waveguide, kusintha kwa waveguide kupita ku waveguide ndi mitundu yosiyanasiyana ya kusintha kwa waveguide. Nkhaniyi ikuyang'ana kwambiri kapangidwe ka kusintha kwa microband SIW.

Mitundu yosiyanasiyana ya zomangamanga zoyendera

Microstripndi imodzi mwa nyumba zowongolera zomwe zimagwiritsidwa ntchito kwambiri pama microwave frequency otsika. Ubwino wake waukulu ndi kapangidwe kosavuta, mtengo wotsika komanso kuphatikiza kwakukulu ndi zigawo zoyikira pamwamba. Mzere wamba wa microstrip umapangidwa pogwiritsa ntchito ma conductor kumbali imodzi ya dielectric layer substrate, ndikupanga malo amodzi pansi mbali inayo, ndi mpweya pamwamba pake. Conductor wapamwamba kwenikweni ndi chinthu chowongolera (nthawi zambiri mkuwa) chopangidwa kukhala waya wopapatiza. M'lifupi mwa mzere, makulidwe, chilolezo choyerekeza, ndi kutayika kwa dielectric kwa substrate ndi magawo ofunikira. Kuphatikiza apo, makulidwe a conductor (monga, makulidwe a metallization) ndi conductivity ya conductor ndizofunikiranso pama frequency apamwamba. Poganizira mosamala magawo awa ndikugwiritsa ntchito mizere ya microstrip ngati gawo loyambira la zida zina, zida zambiri zosindikizidwa za microwave ndi zigawo zake zitha kupangidwa, monga zosefera, ma couplers, ma power dividers/combiners, ma mixer, ndi zina zotero. Komabe pamene ma frequency akuwonjezeka (pamene akusunthira kuma microwave frequency okwera) kutayika kwa ma transmission kumawonjezeka ndipo radiation imachitika. Chifukwa chake, ma waveguide opanda kanthu monga ma waveguide a rectangular amakondedwa chifukwa cha kutayika kochepa pama frequency apamwamba (opanda radiation). Mkati mwa waveguide nthawi zambiri mumakhala mpweya. Koma ngati mukufuna, ikhoza kudzazidwa ndi zinthu zamagetsi, zomwe zimapangitsa kuti ikhale yocheperako kuposa njira yoyendera mafunde yodzaza ndi mpweya. Komabe, njira zoyendera mafunde a chubu chopanda kanthu nthawi zambiri zimakhala zazikulu, zimatha kukhala zolemera makamaka pamafupipafupi otsika, zimafuna zofunikira kwambiri pakupanga ndipo zimakhala zokwera mtengo, ndipo sizingaphatikizidwe ndi nyumba zosindikizidwa za planar.

ZOPANGIRA ANTHENA ZA RFMISO MICROSTRIP:

RM-MA25527-22,25.5-27GHz

RM-MA425435-22,4.25-4.35GHz

Chinanso ndi kapangidwe kowongolera kosakanikirana pakati pa kapangidwe ka microstrip ndi waveguide, kotchedwa substrate integrated waveguide (SIW). SIW ndi kapangidwe kofanana ndi waveguide kophatikizidwa komwe kamapangidwa pa zinthu za dielectric, komwe kali ndi ma conductor pamwamba ndi pansi komanso mzere wa mizere iwiri ya zitsulo zomwe zimapanga makoma am'mbali. Poyerekeza ndi kapangidwe ka microstrip ndi waveguide, SIW ndi yotsika mtengo, ili ndi njira yosavuta yopangira, ndipo imatha kuphatikizidwa ndi zida zozungulira. Kuphatikiza apo, magwiridwe antchito pama frequency apamwamba ndi abwino kuposa a microstrip ndipo ali ndi mawonekedwe ogawa ma waveguide. Monga momwe zasonyezedwera pa Chithunzi 1;

Malangizo a kapangidwe ka SIW

Ma substrate integrated waveguides (SIWs) ndi mapangidwe ofanana ndi mafunde opangidwa pogwiritsa ntchito mizere iwiri ya zitsulo zomwe zimayikidwa mu dielectric yolumikiza mbale ziwiri zachitsulo zofanana. Mizere yachitsulo kudzera m'mabowo imapanga makoma am'mbali. Kapangidwe kameneka kali ndi mawonekedwe a mizere ya microstrip ndi mafunde ozungulira. Njira yopangira imafanananso ndi mapangidwe ena ophwanyika. SIW geometry yachizolowezi ikuwonetsedwa mu Chithunzi 2.1, pomwe m'lifupi mwake (monga kulekana pakati pa mafunde kumbali (as)), m'mimba mwake wa mafunde (d) ndi kutalika kwa pitch (p) zimagwiritsidwa ntchito popanga kapangidwe ka SIW. Ma parameter ofunikira kwambiri a geometric (omwe akuwonetsedwa mu Chithunzi 2.1) adzafotokozedwa mu gawo lotsatira. Dziwani kuti mawonekedwe olamulira ndi TE10, monga momwe mafunde ozungulira amakhalira. Ubale pakati pa mafunde ozungulira fc a mafunde ozungulira odzaza ndi mpweya (AFWG) ndi mafunde ozungulira odzaza ndi dielectric (DFWG) ndi miyeso a ndi b ndiye mfundo yoyamba ya kapangidwe ka SIW. Kwa mafunde ozungulira odzaza ndi mpweya, mafunde ozungulira ndi monga momwe asonyezedwera mu fomula pansipa.

Kapangidwe koyambira ka SIW ndi njira yowerengera [1]

pomwe c ndi liwiro la kuwala mu malo omasuka, m ndi n ndi ma modes, a ndi kukula kwa waveguide yayitali, ndipo b ndi kukula kwa waveguide kochepa. Pamene waveguide ikugwira ntchito mu TE10 mode, imatha kusinthidwa kukhala fc=c/2a; pamene waveguide yadzazidwa ndi dielectric, kutalika kwa broadside a kumawerengedwa ndi ad=a/Sqrt(εr), pomwe εr ndi dielectric constant ya medium; kuti SIW igwire ntchito mu TE10 mode, through hole space p, diameter d ndi wide side monga momwe ziyenera kukhutiritsa fomula yomwe ili kumtunda kumanja kwa chithunzi pansipa, ndipo palinso ma empirical formulas a d<λg ndi p<2d [2];

kumene λg ndi kutalika kwa mafunde otsogozedwa: Nthawi yomweyo, makulidwe a substrate sadzakhudza kapangidwe ka kukula kwa SIW, koma adzakhudza kutayika kwa kapangidwe kake, kotero ubwino wochepa wa substrate zokhala ndi makulidwe apamwamba uyenera kuganiziridwa.

Kusintha kwa Microstrip kukhala SIW
Pamene kapangidwe ka microstrip kakufunika kulumikizidwa ku SIW, kusintha kwa microstrip yopapatiza ndi imodzi mwa njira zazikulu zosinthira zomwe zimakondedwa, ndipo kusintha kopapatiza nthawi zambiri kumapereka machesi ofanana ndi ma transitions ena osindikizidwa. Kapangidwe ka kusintha kokonzedwa bwino kamakhala ndi ma reflections ochepa kwambiri, ndipo kutayika kwa insertion kumachitika makamaka chifukwa cha kutayika kwa dielectric ndi conductor. Kusankhidwa kwa substrate ndi zida za conductor makamaka kumatsimikizira kutayika kwa kusintha. Popeza makulidwe a substrate amalepheretsa m'lifupi mwa mzere wa microstrip, magawo a kusintha kopapatiza ayenera kusinthidwa pamene makulidwe a substrate asintha. Mtundu wina wa coplanar waveguide (GCPW) womwe uli pansi ndi kapangidwe ka mzere wotumizira womwe umagwiritsidwa ntchito kwambiri m'makina apamwamba kwambiri. Ma conductor am'mbali omwe ali pafupi ndi mzere wotumizira wapakati amagwiranso ntchito ngati nthaka. Mwa kusintha m'lifupi mwa feeder yayikulu ndi mpata womwe uli pansi, kulephera kwa khalidwe lofunikira kungapezeke.

Microstrip kupita ku SIW ndi GCPW kupita ku SIW

Chithunzi chomwe chili pansipa ndi chitsanzo cha kapangidwe ka microstrip ku SIW. Medium yomwe imagwiritsidwa ntchito ndi Rogers3003, dielectric constant ndi 3.0, true loss value ndi 0.001, ndipo makulidwe ndi 0.127mm. M'lifupi mwa feeder kumapeto onse awiri ndi 0.28mm, zomwe zikugwirizana ndi m'lifupi mwa antenna feeder. M'mimba mwake mwa dzenje ndi d=0.4mm, ndipo spacing p=0.6mm. Kukula kwa simulation ndi 50mm*12mm*0.127mm. Kutayika konse mu passband ndi pafupifupi 1.5dB (komwe kungachepe kwambiri pokonza spacing ya mbali yayikulu).