Kodi Antena ya Helical ndi Chiyani?
Antena yozungulira, yomwe imadziwikanso kuti antenna ya helix, ndi antenna ya waya yopangidwa ndi kulumikiza waya woyendetsa kapena chubu kukhala helix ya magawo atatu. Malekezero amodzi a helix nthawi zambiri amalumikizidwa ndi kondakitala wapakati wa mzere wolumikizira, pomwe kondakitala wakunja amalumikizidwa ku pulaneti yachitsulo kapena chowunikira.
Maonekedwe ake apadera amalola antenna kugwira ntchito m'njira zosiyanasiyana za radiation kutengera ubale womwe ulipo pakati pa miyeso ya helix ndi kutalika kwa nthawi yogwirira ntchito.
Pakati pa njira izi,mawonekedwe a axialNdikofunikira kwambiri mu RF ndi microwave engineering chifukwa imatha kupereka kuwala kolunjika, bandwidth yotakata, komanso polarization yozungulira. Makhalidwe amenewa amachititsa kuti ma antenna a helical akhale othandiza pa maulalo a satellite, telemetry, tracking, space communication, radio astronomy, ndi ntchito zina zomwe ma antenna angasinthe.
Kuchuluka kwa ntchito ya antenna yozungulira sikungokhala ndi gulu limodzi lokhazikika. M'malo mwake, kumatsimikiziridwa makamaka ndi miyeso yake yowoneka poyerekeza ndi kutalika kwa nthawi. Chifukwa chake, kapangidwe ka helical kamatha kupangidwira machitidwe a VHF ndi UHF komanso kugwiritsa ntchito ma RF ndi ma microwave okhala ndi ma frequency apamwamba.
Chithunzi 1. Chitsanzo cha ma antenna ozungulira omwe amagwiritsidwa ntchito mu dongosolo lolumikizirana lolunjika.
Kapangidwe Koyambira ka Antena ya Helical
Antena yozungulira imakhala ndi zigawo zinayi zazikulu:
- Woyendetsa helikopita
- Chowunikira pansi kapena chowunikira
- Malo operekera chakudya cha RF
- Kapangidwe kothandizira makina
Chozungulira nthawi zambiri chimapangidwa ndi waya wamkuwa, chubu, kapena chinthu china chowongolera mpweya. Mbali imodzi imalumikizidwa ndi kondakitala wapakati wa chingwe chotumizira mpweya cha coaxial, pomwe kondakitala wakunja wa coaxial amalumikizidwa ndi magetsi ku nthaka.
Denga la pansi limathandiza kulamulira njira ya kuwala ndipo limagwira ntchito ngati gawo la kapangidwe ka chakudya cha antenna. Mu mapangidwe ofunikira, kukula kwake kumatha kukhudza kwambiri impedance, magwiridwe antchito a kutsogolo ndi kumbuyo, komanso mawonekedwe a kuwala komwe kumabwera chifukwa cha kuwalako.
Magawo angapo a geometric amatsimikiza momwe antenna imagwirira ntchito pamagetsi:
- D — M'mimba mwake wa Helix
- C - Kuzungulira kwa kutembenukira kumodzi
- S — Kutalikirana pakati pa makhota oyandikana
- N — Chiwerengero cha maulendo
- α — Ngodya ya phula
- L — Utali wonse wa axial
Mzere wozungulira ndi:
[C=\pi D]
Ngodya ya pitch ingafotokozedwe motere:
[\alpha=\tan^{-1}\left(\frac{S}{\pi D}\right)]
Magawo awa sangaganizidwe paokha chifukwa kusintha gawo limodzi kumasintha impedance ya antenna, polarization, beamwidth, gain, ndi frequency yogwirira ntchito.
Chithunzi 2. Kapangidwe ka antenna yozungulira yokhala ndi helix conductor ndi ground-plane reflector.
Mitundu Iwiri Yaikulu Yopangira Ma radiation
Chimodzi mwa zinthu zosangalatsa kwambiri za antenna yozungulira ndichakuti kapangidwe kofananako kamatha kupanga mitundu yosiyanasiyana ya ma radiation kutengera kukula kwake kwamagetsi.
Njira ziwiri zomwe zimakambidwa kwambiri ndi izi:
- Mawonekedwe wamba
- Mawonekedwe a Axial
Kumvetsetsa kusiyana pakati pa njira ziwirizi ndikofunikira posankha kapena kupanga antenna yozungulira.
Antena ya Helical ya Normal-Mode
In mawonekedwe abwinobwino, kukula ndi mtunda wa helix yonse ndi zazing'ono zamagetsi poyerekeza ndi kutalika kwa mafunde.
Ma radiation amayendetsedwa makamaka molunjika ku helix axis osati mozungulira. Khalidwe la maginito limamveka ngati kuphatikiza kwa minda yopangidwa ndi dipole yamagetsi yayifupi ndi kuzungulira pang'ono.
Kutengera ndi mawonekedwe a helix, ngodya ya pitch, kapangidwe ka chakudya, ndi njira yowonera, kugawanika komwe kumachitika kungakhale kolunjika, kozungulira, kapena m'mapangidwe ena ofanana ndi ozungulira.
Ma helikopita a normal-mode nthawi zambiri amakhala ang'onoang'ono, koma kukula kwawo kochepa kwamagetsi kumapangitsa kuti pakhale kukana kochepa kwa ma radiation. Izi zitha kupangitsa kuti ma radiation asamagwire bwino ntchito komanso kuti bandwidth ikhale yocheperako poyerekeza ndi kapangidwe ka axial-mode.
Chifukwa chake ndi othandiza pamene kukula kwa antenna kuli kovuta kwambiri ndipo sikufunika kukwera kwambiri.
Chithunzi 3. Chithunzi chosonyeza kuwala kwa antenna ya helical ya normal-mode.
Antena ya Helical ya Axial-Mode
Themawonekedwe a axial, nthawi zina imatchedwa end-fire mode, ndi kasinthidwe komwe kamagwirizana kwambiri ndi ma antenna a helical ogwira ntchito kwambiri.
Munjira iyi, mphamvu yamagetsi imafalikira makamaka motsatira mzere wa helix, ndikupanga kuwala kolunjika.
Kapangidwe ka axial-mode kamagwiritsa ntchito helix circumference yofanana ndi wavelength imodzi:
[C \pafupifupi \lambda]
Nthawi zambiri, malo ozungulira amakhala motere:
[S \pafupifupi 0.2\lambda \text{ to } 0.3\lambda]
ndipo pafupifupi kotala la mafunde a wavelength ndi malo oyambira ofala.
Pa mapangidwe ambiri achikhalidwe a axial-mode, ma pitch angles ozungulira 12°–14° amagwiritsidwa ntchito nthawi zambiri.
Pansi pa mikhalidwe yoyenera ya geometrical, minda yopangidwa ndi kutembenuka motsatizana imaphatikizana bwino motsatira mzere wa helix. Izi zimapangitsa kuti kuwala kolunjika kukhale kozungulira kapena kozungulira.
Kuchuluka kwa ma turn kumakhudzanso magwiridwe antchito a antenna. Kuchulukitsa kuchuluka kwa ma turn nthawi zambiri kumatha kuwonjezera kuwongolera ndi kukulitsa pamene kumachepetsa kuwala kwakukulu, ngakhale kuti mapangidwe othandiza ayeneranso kuganizira kutalika kwa makina, kutayika kwa kondakitala, kufananiza impedance, ndi zoletsa zoyikira.
Chithunzi 4. Chithunzi chosonyeza kuwala kwa antenna ya axial-mode helical yokhala ndi kuwala kwakukulu kolunjika.
Kugawanika Kozungulira kwa Dzanja Lamanja ndi Dzanja Lamanzere
Chimodzi mwa ubwino waukulu wa antenna ya axial-mode helical ndi kuthekera kwake kwachilengedwe kopanga polarization yozungulira.
Kutengera ndi komwe kumazungulira komanso komwe kumawongoleredwa ndi ma radiation, helix ikhoza kupangidwa kuti ipange izi:
- RHCP — Kugawanika Kozungulira kwa Dzanja Lamanja
- LHCP — Kugawanika Kozungulira kwa Dzanja Lamanzere
Kuzungulira polarization kumathandiza kwambiri makamaka pamene malo olumikizirana pakati pa ma antenna otumizira ndi olandira sangathe kukhala okhazikika.
Mwachitsanzo, ma satellite, zombo zamlengalenga, nsanja zowuluka m'mlengalenga, makina ozungulira, ndi zida zolumikizirana zam'manja zimatha kusintha mawonekedwe nthawi zonse. Antena yozungulira yozungulira imatha kuchepetsa kukhudzidwa kwa kulumikizana kwa kusiyana kwa angular kumeneku.
Kufananiza polarization ndikofunikirabe. Antena ya RHCP imagwirizana bwino ndi antena ya RHCP, pomwe antena ya LHCP nthawi zambiri iyenera kugwirizanitsidwa ndi antena ya LHCP. Polarization yozungulira yosiyana ingayambitse kutayika kwakukulu kwa polarization.
Pakuwunika kwa uinjiniya,chiŵerengero cha axialamagwiritsidwa ntchito kwambiri pofotokoza khalidwe la polarization yozungulira. Mafunde abwino ozungulira okhala ndi polarized ali ndi axial ratio ya 0 dB, pomwe ma antenna ozungulira okhala ndi polarized nthawi zambiri amayesedwa motsutsana ndi kufunikira kwa axial-ratio yodziwika bwino kudutsa ma frequency ndi angular range omwe amafunidwa.
Zinthu Zomwe Zimakhudza Kugwira Ntchito kwa Antena ya Helical
Khalidwe la antenna yozungulira limagwirizana kwambiri ndi mawonekedwe ake.
Zofunikira pakupanga zinthu ndi izi:
Kuzungulira kwa Helix
Ubale pakati pa circumference ndi wavelength umachita gawo lalikulu pakutsimikiza ngati antenna imagwira ntchito mu normal mode kapena axial mode.
Kutalikirana kwa Malo Ozungulira
Kutalikirana kumakhudza ubale wa magawo pakati pa mafunde omwe ali pafupi ndipo motero zimakhudza kutsogolera kwa kuwala, impedance, ndi polarization.
Ngodya Yoyenda
Ngodya ya pitch imafotokoza momwe helix imayendera mofulumira motsatira mzere wake. Ndi chinthu chofunikira kwambiri kuti munthu akhalebe ndi khalidwe lokhazikika la axial-mode.
Chiwerengero cha Mapeto
Kutembenuka kwambiri nthawi zambiri kumawonjezera kutsegula kwa magetsi ndipo kungapereke chiwongolero chapamwamba, komanso kumawonjezera kutalika kwa antenna ndi zovuta zamakina.
Ndege Yapansi
Kukula ndi mawonekedwe a chowunikiracho zimakhudza mawonekedwe a radiation yakutsogolo, impedance, ndi radiation yakumbuyo.
Kufananiza Chakudya ndi Impedance
Ngakhale ndi miyeso yolondola ya helix, kufananiza kolakwika kwa impedance kumatha kuwonjezera mphamvu yowunikira ndikuchepetsa magwiridwe antchito a antenna. Chifukwa chake, mapangidwe othandiza ayenera kuwunika kutayika kobwerera kapena VSWR pamodzi ndi mawonekedwe a radiation.
Chitsanzo ndi Kupeza Mphamvu ya Radiation
Mu mawonekedwe a axial, antenna yozungulira imapanga kuwala kwakukulu komwe kumazungulira mozungulira mzere wa helix.
Pamene kutalika kwa magetsi ndi kuchuluka kwa ma turn akuwonjezeka, kuwala kwakukulu nthawi zambiri kumakhala kocheperapo ndipo mayendedwe a antenna amawonjezeka. Ma lobes am'mbali amathanso kuwonekera, makamaka m'mapangidwe ataliatali kapena osakonzedwa bwino.
Chifukwa chake, antenna sayenera kuyesedwa ndi phindu lokha. Mainjiniya nthawi zambiri amaganizira makhalidwe angapo pamodzi:
- Phindu
- Phindu lodziwika
- Mpweya wa theka la mphamvu
- Chiŵerengero cha Axial
- VSWR kapena kutayika kobwerera
- Chiŵerengero cha kutsogolo ndi kumbuyo
- Mulingo wa mbali ya lobe
- Kuyera kwa polarization
- Kugwiritsa ntchito bwino kwa kuwala kwa dzuwa
Kuphatikiza kwa magawo kumeneku kumapereka chithunzi chokwanira kwambiri cha momwe antenna imagwirira ntchito kuposa phindu limodzi lokha.
Ubwino wa Ma Helical Antennas
Ma antenna a helical amapereka maubwino angapo othandiza paukadaulo:
- Kapangidwe ka makina kosavuta
- Mphamvu yachilengedwe yozungulira-polarization mu axial mode
- Bandwidth yothandiza yogwiritsira ntchito
- Kuchita bwino kolunjika
- Ma geometry osinthika amitundu yosiyanasiyana ya ma frequency
- Kukhazikitsa kwa RHCP kapena LHCP kosinthasintha
- Yoyenera ma antenna apadera kapena ma antenna osiyanasiyana
Zolepheretsa Kupanga
Palinso zinthu zingapo zofunika kuziganizira:
- Mapangidwe a Axial-mode angafunike kutalika kwakukulu
- Kupeza bwino nthawi zambiri kumafuna kutembenuka kwambiri motero antenna yayitali
- Kugwira ntchito kumadalira kwambiri kulondola kwa jiyomethri
- Miyeso ya pansi pa nthaka imakhudza mawonekedwe a kuwala kwa dzuwa
- Kufananiza chakudya kuyenera kupangidwa bwino
- Thandizo la makina limakhala lofunika kwambiri pa nthawi yowerengera nthawi
- Kuzindikira kozungulira-polarization kosiyana kungapangitse kutayika kwakukulu kwa polarization
Mapulogalamu Odziwika
Ma antenna a helical amapezeka m'njira zosiyanasiyana za RF, kuphatikizapo:
- Kulankhulana kwa satellite
- Telemetry ndi kutsatira za mlengalenga
- Kulankhulana ndi siteshoni yapansi panthaka
- Kupenda zakuthambo kwa wailesi
- Machitidwe olumikizirana ndi ndege ndi ndege
- Telemetry ya RF
- Maulalo a VHF ndi UHF otsogolera
- Kuzindikira patali
- Kuyeza ndi kufufuza ma antenna
- Kuyesera kozungulira-kugawaniza
- Kuyesa kwa makina olumikizirana
Chifukwa Chake Ma Helical Antennas Ndi Ofunika Mu RF Engineering
Antena yozungulira ndi chitsanzo chabwino kwambiri cha momwe mawonekedwe a antena amalamulira machitidwe a maginito.
Mwa kusintha magawo monga kuzungulira, malo, ngodya ya pitch, ndi kuchuluka kwa ma turn, mainjiniya amatha kusuntha kuchokera ku radiator yaying'ono ya broadside kupita ku antenna yozungulira yozungulira.
Ubale uwu pakati pa geometry yeniyeni ndi magwiridwe antchito amagetsi ndi wofunikanso pophunzira ukadaulo wapamwamba kwambiri wa antenna monga ma antenna ozungulira okhala ndi polarized horn, ma antenna arrays, ma antenna a satellite, ma antenna oyezera broadband, ndi machitidwe olumikizirana a microwave.
RF MISO imapanga ma antenna ndi zigawo za microwave kuti zigwiritsidwe ntchito poyesa ma RF, kulumikizana, radar, kuyeza ma antenna, ndi kugwiritsa ntchito njira zolumikizirana ndi makina. Kumvetsetsa kapangidwe ka ma antenna oyambira monga helical antenna kumathandiza mainjiniya kuwunika bwino magawo ofunikira kuphatikiza kuchuluka kwa ma frequency, gain, polarization, axial ratio, beamwidth, VSWR, ndi radiation pattern.
Kuti mudziwe zambiri zokhudza ma antenna, chonde pitani ku:
Nthawi yotumizira: Ogasiti-07-2026
