Kugawa kwa ma antenna ndi chimodzi mwa zinthu zofunika kwambiri pa ma antenna. Choyamba tiyenera kumvetsetsa momwe mafunde a ndege amagawidwira. Kenako tikhoza kukambirana za mitundu ikuluikulu ya kugawa kwa ma antenna.
kugawanika kwa mzere
Tiyamba kumvetsetsa polarization ya mafunde amagetsi a ndege.
Mafunde a planar electromagnetic (EM) ali ndi makhalidwe angapo. Choyamba ndi chakuti mphamvu imayenda mbali imodzi (palibe gawo lomwe limasintha mbali ziwiri). Chachiwiri, mphamvu yamagetsi ndi mphamvu yamagetsi zimakhala zolunjika kwa wina ndi mnzake ndipo zimakhala zolunjika kwa wina ndi mnzake. Mphamvu yamagetsi ndi mphamvu yamagetsi zimakhala zolunjika kwa njira yofalitsira mafunde a ndege. Mwachitsanzo, taganizirani mphamvu yamagetsi yamagetsi ya frequency imodzi (E field) yoperekedwa ndi equation (1). Mphamvu yamagetsi ikuyenda mbali ya +z. Mphamvu yamagetsi imayang'aniridwa mbali ya +x. Mphamvu yamagetsi ili mbali ya +y.
Mu equation (1), onani mawu oti: . Iyi ndi vekitala ya unit (vekitala ya kutalika), yomwe imati mfundo yamagetsi ili mbali ya x. Mafunde a ndege akuwonetsedwa mu Chithunzi 1.
chithunzi 1. Chithunzi chosonyeza mphamvu yamagetsi yomwe ikuyenda mbali ya +z.
Polarization ndi mawonekedwe a trace ndi propagation (contour) ya magetsi. Mwachitsanzo, taganizirani za plane wave electric field equation (1). Tiona malo omwe magetsi ali (X,Y,Z) = (0,0,0) ngati nthawi. Kutalika kwa malowa kwawonetsedwa mu Chithunzi 2, nthawi zingapo panthawi. Malowa akusinthasintha pafupipafupi "F".
chithunzi 2. Yang'anani mphamvu yamagetsi (X, Y, Z) = (0,0,0) nthawi zosiyanasiyana.
Mphamvu yamagetsi imawonekera poyambira, ikugwedezeka mmbuyo ndi mtsogolo mu amplitude. Mphamvu yamagetsi nthawi zonse imakhala motsatira x-axis yomwe yasonyezedwa. Popeza mphamvu yamagetsi imasungidwa motsatira mzere umodzi, mphamvu iyi inganenedwe kuti ndi yolumikizidwa molunjika. Kuphatikiza apo, ngati X-axis ili yofanana ndi nthaka, mphamvu iyi imafotokozedwanso kuti ndi yolumikizidwa mopingasa. Ngati mphamvu yamagetsi ili motsatira Y-axis, mphamvu yamagetsi inganenedwe kuti ndi yolumikizidwa mopingasa.
Mafunde ozungulira mzere safunika kuyendetsedwa motsatira mzere wopingasa kapena wowongoka. Mwachitsanzo, mafunde amagetsi okhala ndi choletsa chomwe chili pamzere monga momwe zasonyezedwera pa Chithunzi 3 nawonso angapangidwe mozungulira mzere.
chithunzi 3. Mphamvu yamagetsi ya mafunde ozungulira omwe ali ndi ngodya.
Munda wamagetsi womwe uli pa Chithunzi 3 ukhoza kufotokozedwa ndi equation (2). Tsopano pali gawo la x ndi y la munda wamagetsi. Zigawo zonse ziwiri ndi zofanana kukula.
Chinthu chimodzi choyenera kudziwa pa equation (2) ndi xy-component ndi electronic fields mu gawo lachiwiri. Izi zikutanthauza kuti zigawo zonse ziwiri zimakhala ndi amplitude yofanana nthawi zonse.
kugawanika kozungulira
Tsopano tiyerekeze kuti mphamvu yamagetsi ya mafunde a ndege yaperekedwa ndi equation (3):
Pankhaniyi, zinthu za X- ndi Y zili kunja kwa gawo la madigiri 90. Ngati gawolo likuwoneka ngati (X, Y, Z) = (0,0,0) monga kale, gawo lamagetsi motsutsana ndi nthawi lidzawonekera monga momwe zasonyezedwera pansipa pa Chithunzi 4.
Chithunzi 4. Mphamvu yamagetsi (X, Y, Z) = (0,0,0) EQ domain. (3).
Mphamvu yamagetsi yomwe ili pa Chithunzi 4 imazungulira mozungulira. Mtundu uwu wa mphamvu yamagetsi umafotokozedwa ngati mafunde ozungulira. Pa kusinthasintha kozungulira, mfundo zotsatirazi ziyenera kukwaniritsidwa:
- Muyezo wa polarization yozungulira
- Malo ogwiritsira ntchito magetsi ayenera kukhala ndi zigawo ziwiri zozungulira (zopingasa).
- Zigawo zozungulira za magetsi ziyenera kukhala ndi ma amplitude ofanana.
- Zigawo za quadrature ziyenera kukhala madigiri 90 kunja kwa gawo.
Ngati mukuyenda pa sikirini ya Wave Figure 4, kuzungulira kwa munda kumanenedwa kuti kuli kozungulira mozungulira ndi dzanja lamanja (RHCP). Ngati munda wazunguliridwa mozungulira, munda udzakhala wozungulira mozungulira ndi dzanja lamanzere (LHCP).
Kugawanika kwa elliptical
Ngati gawo lamagetsi lili ndi zigawo ziwiri zopingasa, madigiri 90 kunja kwa gawo koma zofanana, gawolo lidzagawika mozungulira. Poganizira gawo lamagetsi la mafunde a ndege omwe akuyenda motsatira +z, lofotokozedwa ndi Equation (4):
Malo a nsonga ya vekitala yamagetsi adzaganiziridwa kuti aperekedwa mu Chithunzi 5
Chithunzi 5. Mphamvu yamagetsi ya mafunde ozungulira ozungulira. (4).
Munda womwe uli mu Chithunzi 5, womwe ukuyenda mozungulira wotchi, ungakhale wozungulira ndi dzanja lamanja ngati ukutuluka pazenera. Ngati vector yamagetsi izungulira mbali ina, mundawo udzakhala wozungulira ndi dzanja lamanzere.
Kuphatikiza apo, kugawikana kwa elliptical kumatanthauza kugawikana kwake. Chiŵerengero cha kugawikana ndi kukula kwa ma axes akuluakulu ndi ang'onoang'ono. Mwachitsanzo, kugawikana kwa mafunde kuchokera ku equation (4) ndi 1/0.3 = 3.33. Mafunde ogawikana a elliptical amafotokozedwanso ndi malangizo a axis yayikulu. Equation ya mafunde (4) ili ndi mzere wozungulira womwe uli ndi x-axis. Dziwani kuti mzere waukulu ukhoza kukhala pa ngodya iliyonse. Ngodya sikofunikira kuti igwirizane ndi mzere wa X, Y kapena Z. Pomaliza, ndikofunikira kuzindikira kuti kugawikana kozungulira ndi kolunjika ndi milandu yapadera ya kugawikana kwa elliptical. Mafunde ogawikana a elliptical 1.0 ndi mafunde ozungulira. Mafunde ogawikana a elliptical okhala ndi kugawikana kosatha. Mafunde ogawikana a linearly.
Kugawanika kwa ma antenna
Tsopano popeza tadziwa za malo olumikizirana mafunde a maginito a ndege, kusinthasintha kwa maginito a antenna kumangofotokozedwa mosavuta.
Kugawa kwa Ma Antena Kuwunika kwa ma antenna akutali, kugawa kwa gawo lowala lomwe latuluka. Chifukwa chake, ma antenna nthawi zambiri amalembedwa ngati "ma linearly polarized" kapena "ma antenna ozungulira a dzanja lamanja".
Lingaliro losavuta ili ndi lofunika kwambiri pa kulumikizana kwa antenna. Choyamba, antenna yopingasa singalumikizane ndi antenna yopingasa yopingasa. Chifukwa cha chiphunzitso cha reciprocity, antenna imatumiza ndikulandira mwanjira yomweyo. Chifukwa chake, antenna yopingasa yopingasa imatumiza ndikulandira minda yopingasa yopingasa. Chifukwa chake, ngati muyesa kutumiza antenna yopingasa yopingasa yopingasa, sipadzakhala kulandira.
Kawirikawiri, pa ma antenna awiri ozungulira molunjika omwe amazunguliridwa mozungulira wina ndi mnzake ndi ngodya ( ), kutayika kwa mphamvu chifukwa cha kusagwirizana kwa polarization kumeneku kudzafotokozedwa ndi polarization loss factor (PLF):
Chifukwa chake, ngati ma antenna awiri ali ndi polarization yofanana, ngodya pakati pa minda yawo ya ma electron yowala ndi zero ndipo palibe kutayika kwa mphamvu chifukwa cha kusagwirizana kwa polarization. Ngati antenna imodzi yakhala ndi polarized molunjika ndipo inayo yakhala ndi polarized mopingasa, ngodyayo ndi madigiri 90, ndipo palibe mphamvu yomwe idzasamutsidwa.
ZINDIKIRANI: Kusuntha foni pamwamba pa mutu wanu m'makona osiyanasiyana kumafotokoza chifukwa chake nthawi zina kulandira foni kumatha kuwonjezeka. Ma antenna a foni nthawi zambiri amakhala ndi ma polarized, kotero kuzungulira foni nthawi zambiri kumatha kufanana ndi kupolarization kwa foni, zomwe zimapangitsa kuti foni ilandire bwino.
Kuzungulira polarization ndi khalidwe lofunika kwambiri la ma antenna ambiri. Ma antenna onsewa ali ndi polarization yozungulira ndipo samataya chizindikiro chifukwa cha kusagwirizana kwa polarization. Ma antenna omwe amagwiritsidwa ntchito mu GPS systems ali ndi polarization yozungulira ya dzanja lamanja.
Tsopano tiyerekeze kuti antenna yozungulira yokhala ndi polarized imalandira mafunde ozungulira okhala ndi polarized. Mofananamo, tiyerekeze kuti antenna yozungulira yokhala ndi polarized imayesa kulandira mafunde ozungulira okhala ndi polarized. Kodi zotsatira zake ndi chiyani?
Kumbukirani kuti polarization yozungulira kwenikweni ndi mafunde awiri ozungulira, ozungulira madigiri 90 kunja kwa gawo. Chifukwa chake, antenna yozungulira (LP) idzalandira gawo la mafunde lozungulira (CP) lozungulira. Chifukwa chake, antenna ya LP idzakhala ndi kutayika kwa polarization kwa 0.5 (-3dB). Izi ndi zoona mosasamala kanthu kuti antenna ya LP yazunguliridwa ndi ngodya yanji. Chifukwa chake:
Chinthu chotayika cha polarization nthawi zina chimatchedwa polarization efficiency, antenna mismatch factor, kapena antenna reception factor. Mayina onsewa amatanthauza lingaliro lomwelo.
Nthawi yotumizira: Disembala-22-2023
