1.Kodi Antenna ndi chiyani?
Monga tonse tikudziwa, pali mitundu yonse ya wzida zolumikizirana zopanda ntchitom'miyoyo yathu, monga drone video downlink,ulalo wopanda waya wa robot, digito ma mesh systemndipo makina otumizira mawayilesiwa amagwiritsa ntchito mafunde a wailesi kufalitsa mauthenga opanda zingwe monga mavidiyo, mawu ndi deta.Mlongoti ndi chipangizo chomwe chimagwiritsidwa ntchito poyatsira ndi kulandira mafunde a wailesi.
2. Chingwe cha bandwidth
Pamene ma frequency ogwiritsira ntchito antenna akusintha, kuchuluka kwa kusintha kwa magawo amagetsi oyenerera a mlongoti kumakhala mkati mwazovomerezeka.Ma frequency ovomerezeka ovomerezeka panthawiyi ndi antenna frequency band wide, yomwe nthawi zambiri imatchedwa bandwidth.Mlongoti uliwonse uli ndi bandwidth inayake yogwiritsira ntchito, ndipo ilibe zotsatira zofanana kunja kwa band frequency.
Mtheradi bandwidth: ABW=fmax - fmin
Chibale bandwidth: FBW=(fmax - fmin)/f0×100%
f0=1/2(fmax + fmin) ndiye ma frequency apakati
Pamene mlongoti umagwira ntchito pakatikati, chiŵerengero cha mafunde oyimilira ndichochepa kwambiri ndipo mphamvu zake zimakhala zapamwamba kwambiri.
Chifukwa chake, mawonekedwe a bandwidth wachibale amafotokozedwa motere: FBW=2(fmax- fmin)/(fmax+ fmin)
Chifukwa bandwidth ya antenna ndi kuchuluka kwa ma frequency ogwiritsira ntchito pomwe chimodzi kapena zina mwamagetsi amagetsi a mlongoti zimakwaniritsa zofunikira, magawo osiyanasiyana amagetsi angagwiritsidwe ntchito kuyeza kuchuluka kwa bandi.Mwachitsanzo, pafupipafupi gulu m'lifupi lolingana ndi 3dB lobe m'lifupi (lobe m'lifupi amatanthauza ngodya pakati pa mfundo ziwiri pamene mphamvu cheza amachepetsa ndi 3dB, ndiko kuti, mphamvu kachulukidwe amachepetsa ndi theka, mbali zonse za malangizo pazipita ma radiation. ya lobe yayikulu), ndi frequency band m'lifupi pomwe mafunde oyimirira amakwaniritsa zofunikira zina.Zina mwa izo, zomwe zimagwiritsidwa ntchito kwambiri ndi bandwidth yomwe imayesedwa ndi chiŵerengero cha mafunde oima.
3.Kugwirizana pakati pa mafupipafupi ogwiritsira ntchito ndi kukula kwa mlongoti
Momwemonso, kuthamanga kwa mafunde a electromagnetic ndikotsimikizika (kufanana ndi liwiro la kuwala mu vacuum, yolembedwa c≈3 × 108m/s).Malinga ndi c=λf, zitha kuwoneka kuti kutalika kwa mafunde kumayenderana ndi ma frequency, ndipo awiriwo ndiwo maubale ogwirizana.
Kutalika kwa mlongoti kumayenderana mwachindunji ndi kutalika kwa mafunde komanso mosiyana ndi pafupipafupi.Ndiko kuti, kumtunda kwafupipafupi, kufupikitsa kutalika kwa mafunde, ndi kufupikitsa mlongoti angapangidwe.Zachidziwikire, kutalika kwa mlongoti nthawi zambiri sikufanana ndi utali umodzi, koma nthawi zambiri ndi 1/4 wavelength kapena 1/2 wavelength (nthawi zambiri utali wofanana ndi ma frequency apakati amagwiritsidwa ntchito).Chifukwa pamene utali wa kondakitala uli wochuluka wochuluka wa 1/4 wavelength, kondakitala amawonetsa mawonekedwe a resonance pamafupipafupi a kutalika kwa mawonekedwewo.Kutalika kwa kondakitala ndi 1/4 wavelength, kumakhala ndi mawonekedwe a resonance, ndipo kutalika kwa kondakitala ndi 1/2 wavelength, kumakhala ndi mawonekedwe ofanana.Munthawi ya resonance iyi, tinyanga timawala kwambiri ndipo kutembenuza ndi kulandirira bwino kumakhala kwakukulu.Ngakhale ma radiation a oscillator amapitilira 1/2 ya kutalika kwa mawonekedwe, ma radiation apitiliza kukulitsidwa, koma ma radiation odana ndi gawo la gawo lochulukirapo amatulutsa kuletsa, kotero kuti mphamvu yonse ya radiation imasokonekera.Chifukwa chake, tinyanga tating'ono timagwiritsa ntchito gawo la kutalika kwa oscillator la 1/4 wavelength kapena 1/2 wavelength.Pakati pawo, mlongoti wa 1/4-wavelength makamaka umagwiritsa ntchito dziko lapansi ngati galasi m'malo mwa theka-wave antenna.
1/4 wavelength antenna imatha kukwaniritsa chiwongola dzanja choyenera komanso kugwiritsa ntchito posintha masanjidwewo, ndipo nthawi yomweyo, imatha kusunga malo oyika.Komabe, tinyanga tautaliwu nthawi zambiri timapeza phindu lochepa ndipo sizingakwaniritse zosowa za njira zina zopezera phindu lalikulu.Pankhaniyi, tinyanga ta 1/2-wavelength nthawi zambiri zimagwiritsidwa ntchito.
Kuonjezera apo, zatsimikiziridwa mu chiphunzitso ndi machitidwe kuti 5/8 wavelength array (kutalika uku kuli pafupi ndi 1/2 wavelength koma ali ndi ma radiation amphamvu kuposa 1/2 wavelength) kapena 5/8 wavelength kutsitsa kufupikitsa array (pali koyilo yotsegula pa theka la mtunda wotalikirapo kuchokera pamwamba pa mlongoti) imathanso kupangidwa kapena kusankhidwa kuti ipeze mlongoti wotchipa komanso wopindula kwambiri.
Tingaone kuti pamene tidziwa pafupipafupi ntchito mlongoti, tikhoza kuwerengera lolingana wavelength, ndiyeno pamodzi ndi chiphunzitso kufala mzere, zinthu unsembe danga ndi kufala zofunika kupindula, tingathe pafupifupi kudziwa kutalika kwa mlongoti chofunika. .
Nthawi yotumiza: Oct-13-2023
