He aha ka Antenna Helical?
ʻO ka antenna helical, i ʻike ʻia hoʻi he antenna helix, he antenna uea i hana ʻia ma ka wili ʻana i kahi uea alakaʻi a i ʻole ka paipu i loko o kahi helix ʻekolu-dimensional. Hoʻopili maʻamau ʻia kekahi ʻaoʻao o ka helix i ke alakaʻi waena o ka laina hānai, ʻoiai ua hoʻopili ʻia ke alakaʻi waho i kahi mokulele honua metala a i ʻole reflector.
ʻO kona ʻano geometry ʻokoʻa e ʻae i ka antenna e hana i nā ʻano radiation like ʻole ma muli o ka pilina ma waena o nā ana helix a me ka nalu hana.
Ma waena o kēia mau ʻano, nāʻano axialhe mea nui loa ia i ka ʻenekinia RF a me ka microwave no ka mea hiki iā ia ke hāʻawi i ka radiation kuhikuhi, ka bandwidth ākea, a me ka polarization circular. ʻO kēia mau ʻano e hoʻolilo i nā antennas helical i mea pono i nā loulou ukali, telemetry, tracking, kamaʻilio ākea, radio astronomy, a me nā noi ʻē aʻe kahi e loli ai ke kuhikuhi antenna.
ʻAʻole i kaupalena ʻia ke alapine hana o kahi antenna helical i hoʻokahi kāʻei paʻa. Akā, ua hoʻoholo nui ʻia e kona mau ana kino e pili ana i ka nalu. No laila, hiki ke hoʻolālā ʻia nā ʻano helical no nā ʻōnaehana VHF a me UHF a me nā noi RF a me microwave kiʻekiʻe.
Kiʻi 1. Laʻana o nā antenna helical i hoʻohana ʻia i loko o kahi ʻōnaehana kamaʻilio kuhikuhi.
ʻO ke ʻano kumu o kahi Antenna Helical
ʻO kahi antenna helical maʻamau he ʻehā mau ʻāpana nui:
- Alakaʻi helical
- Papahele honua a i ʻole mea hōʻike
- Wahi hānai RF
- ʻAno kākoʻo mīkini
Hana pinepine ʻia ka helix mai ka uea keleawe, ka paipu, a i ʻole kekahi mea alakaʻi ʻē aʻe. Hoʻopili ʻia kekahi ʻaoʻao i ke alakaʻi waena o kahi laina hoʻoili coaxial, ʻoiai ua hoʻopili uila ʻia ke alakaʻi waho coaxial i ka mokulele honua.
Kōkua ka mokulele honua i ka hoʻokele ʻana i ke kuhikuhi o ka radiation a hana ma ke ʻano he ʻāpana o ka ʻōnaehana hānai antenna. I nā hoʻolālā kūpono, hiki i kona mau ana ke hoʻololi nui i ka impedance, ka hana mua-a-hope, a me ke ʻano radiation hopena.
Hoʻoholo kekahi mau ʻano geometric i ke ʻano uila o ka antenna:
- D — Anawaena Helix
- C - Ka pōʻai o hoʻokahi huli
- S — Ka mamao ma waena o nā huli e pili ana
- N — Helu o nā huli
- α — Ke kihi pitch
- L — Ka lōʻihi axial holoʻokoʻa
ʻO ke anapuni:
[C=\pi D]
Hiki ke hōʻike ʻia ke kihi pitch penei:
[\alpha=\tan^{-1}\left(\frac{S}{\pi D}\right)]
ʻAʻole hiki ke noʻonoʻo kūʻokoʻa ʻia kēia mau palena no ka mea ʻo ka hoʻololi ʻana i hoʻokahi ana e hoʻololi i ka impedance, polarization, beamwidth, gain, a me ka alapine hana o ka antenna.
Kiʻi 2. ʻO ke ʻano antenna helical maʻamau me ke alakaʻi helix a me ka mea hōʻike honua.
ʻElua mau ʻano hoʻolaha nui
ʻO kekahi o nā hiʻohiʻona hoihoi loa o kahi antenna helical ʻo ia ka hiki i ke ʻano kumu like ke hana i nā ʻano radiation like ʻole ma muli o kona nui uila.
ʻO nā ʻano hana ʻelua i kūkākūkā pinepine ʻia:
- ʻAno maʻamau
- ʻAno axial
ʻO ka hoʻomaopopo ʻana i ka ʻokoʻa ma waena o kēia mau ʻano ʻelua he mea nui ia i ke koho ʻana a i ʻole ka hoʻolālā ʻana i kahi antenna helical.
ʻAntenna Helical ʻAno Maʻamau
In ʻano maʻamau, he liʻiliʻi uila ke anawaena holoʻokoʻa a me ka mamao o ka helix i ka hoʻohālikelike ʻia me ka nalu.
Hoʻokele nui ʻia ka radiation ma kahi kokoke i ke axis helix ma mua o ia. Hiki ke hoʻomaopopo ʻia ke ʻano electromagnetic ma ke ʻano he hui pū ʻana o nā kahua i hana ʻia e kahi dipole uila pōkole a me kahi loop liʻiliʻi.
Ma muli o ke ʻano helix, ke kihi pitch, ka hoʻonohonoho hānai ʻana, a me ke kuhikuhi nānā ʻana, hiki i ka polarization hopena ke linear, elliptical, a i ʻole ma kekahi mau hoʻolālā kokoke i ka pōʻai.
ʻO ka maʻamau, he liʻiliʻi nā helices mode maʻamau, akā ʻo ko lākou nui liʻiliʻi uila e hopena i ka pale ʻana i ka radiation haʻahaʻa. Hiki i kēia ke alakaʻi i ka pono radiation haʻahaʻa a me ka bandwidth haiki ma mua o kahi hoʻolālā axial-mode.
No laila, he mea pono lākou i ka wā he palena nui ka nui o ka antenna a ʻaʻole koi ʻia ka loaʻa kiʻekiʻe loa.
Kiʻi 3. ʻAno hoʻohālikelike o ka radiation o kahi antenna helical maʻamau.
ʻAntenna Helical Axial-Mode
ʻO kaʻano axial, i kekahi manawa i kapa ʻia ʻo end-fire mode, ʻo ia ke ʻano hoʻonohonoho i pili pinepine ʻia me nā antennas helical hana kiʻekiʻe.
Ma kēia ʻano, hoʻolaha nui ʻia ka ikehu electromagnetic ma ke axis o ka helix, e hana ana i kahi kukuna kuhikuhi.
Hoʻohana kahi hoʻolālā axial-mode maʻamau i kahi anapuni helix e like me hoʻokahi nalu:
[C \approx \lambda]
ʻO ka mamao o ka huli ʻana a puni pinepine:
[S \approx 0.2\lambda \text{ a i } 0.3\lambda]
me kahi hapaha o ka nalu he wahi hoʻomaka maʻamau.
No nā hoʻolālā axial-mode maʻamau he nui, hoʻohana pinepine ʻia nā kihi pitch a puni 12°–14°.
Ma lalo o nā kūlana geometric kūpono, hui pū nā kahua i hana ʻia e nā huli hope ma ke axis helix. Hoʻopuka kēia i kahi kukuna kuhikuhi me ka polarization pōʻai a kokoke paha i ka pōʻai.
Hoʻopilikia pū ka helu o nā huli i ka hana antenna. ʻO ka hoʻonui ʻana i ka helu o nā huli hiki ke hoʻonui i ka directivity a me ka loaʻa ʻana me ka hoʻohaiki ʻana i ke kukuna nui, ʻoiai pono e noʻonoʻo nā hoʻolālā hana i ka lōʻihi mechanical, ka pohō conductor, ka impedance matching, a me nā palena hoʻonohonoho.
Kiʻi 4. Hoʻohālikelike i ke ʻano hoʻohāliʻi antenna helical axial-mode me kahi kukuna nui kuhikuhi.
ʻO ka Polarization Pōʻai Lima ʻĀkau a me ka Lima Hema
ʻO kekahi o nā pono nui o kahi antenna helical axial-mode ʻo kona hiki kūlohelohe ke hana i ka polarization circular.
Ma muli o ke kuhikuhi o ka wili a me ke kuhikuhi o ka radiation, hiki ke hoʻolālā ʻia kahi helix e hana i kekahi:
- RHCP — Polarization Pōʻai Lima ʻĀkau
- LHCP — Polarization Pōʻai Lima Hema
He mea pono loa ka polarization pōʻai i ka wā ʻaʻole hiki ke paʻa ka kuhikuhi pili ma waena o nā antennas hoʻouna a me ka loaʻa ʻana.
Eia kekahi laʻana, hiki i nā satelite, nā mokulele, nā kahua mokulele, nā ʻōnaehana wili, a me nā lako kamaʻilio kelepona ke hoʻololi mau i ke kuhikuhi. Hiki i kahi antenna polarized circular ke hōʻemi i ka ʻike o ka loulou kamaʻilio i kēia ʻokoʻa angular.
He mea nui nō naʻe ka hoʻohālikelike ʻana o ka polarization. ʻO kahi antenna RHCP e kamaʻilio maikaʻi me kahi antenna RHCP, ʻoiai ʻo kahi antenna LHCP e hoʻopili pinepine ʻia me kahi antenna LHCP. Hiki i nā polarizations poepoe ʻē aʻe ke hopena i ka pohō polarization nui.
No ka loiloi ʻenekinia,lakio axialHoʻohana pinepine ʻia e wehewehe i ke ʻano o ka polarization circular. ʻO kahi nalu polarized circular kūpono he 0 dB axial ratio, ʻoiai ua loiloi pinepine ʻia nā antennas polarized circular kūpono e kūʻē i kahi koi axial-ratio i kuhikuhi ʻia ma waena o ke alapine i makemake ʻia a me ka laulā angular.
Nā Kumu e Hoʻopilikia ana i ka Hana Antenna Helical
Pili loa ke ʻano o kahi antenna helical i kona geometry.
ʻO nā palena hoʻolālā koʻikoʻi:
Kaapuni Helix
ʻO ka pilina ma waena o ke anapuni a me ka nalu he kuleana nui ia i ka hoʻoholo ʻana inā hana ka antenna ma ke ʻano maʻamau a i ʻole ke ʻano axial.
Ka Hoʻokaʻawale ʻana o ka Huli
Hoʻopilikia ka hoʻokaʻawale ʻana i ka pilina pae ma waena o nā au ma nā huli e pili ana a no laila e hoʻopilikia i ke kuhikuhi o ke kukuna, ka impedance, a me ka polarization.
Ke kihi o ke kiʻekiʻe
Hōʻike ka kihi pitch i ka wikiwiki o ka holomua ʻana o ka helix ma kona axis. He mea nui ia no ka mālama ʻana i ke ʻano axial-mode paʻa.
Helu o nā Huli
ʻO ka nui o nā huli e hoʻonui i ka puka uila a hiki ke hāʻawi i ke kuhikuhi kiʻekiʻe, akā hoʻonui pū lākou i ka lōʻihi antenna a me ka paʻakikī mechanical.
Papahele Honua
Hoʻopili ka nui a me ke ʻano o ka mea hōʻike i ke ʻano hoʻoheheʻe mua, ka impedance, a me ka hoʻoheheʻe hope.
Ka Hoʻohālikelike ʻana o ka Hānai a me ka Impedance
ʻOiai me nā ana helix pololei, hiki i ka hoʻohālikelike impedance maikaʻi ʻole ke hoʻonui i ka mana i hōʻike ʻia a hōʻemi i ka hana antenna i ʻike ʻia. No laila, pono nā hoʻolālā hana e loiloi i ka pohō hoʻihoʻi a i ʻole VSWR me nā ʻano radiation.
ʻAno Hoʻolaha a me ka Loaʻa
Ma ke ʻano axial, hoʻopuka kahi antenna helical i kahi kukuna nui i kau ʻia ma kahi o ke axis helix.
I ka piʻi ʻana o ka lōʻihi uila a me ka helu o nā huli, lilo ka kukuna nui i mea haiki a piʻi ka kuhikuhi ʻana o ka antenna. Hiki ke ʻike ʻia nā lobes ʻaoʻao, ʻoi aku hoʻi i nā hale lōʻihi a i ʻole nā hale i hoʻonohonoho ʻole ʻia.
No laila, ʻaʻole pono e loiloi ʻia ka antenna ma o ka loaʻa wale nō. Hoʻomaopopo pinepine nā ʻenekinia i kekahi mau ʻano like ʻole:
- Loaʻa
- Loaʻa i ʻike ʻia
- Ka laulā kukuna hapalua mana
- Laki axial
- VSWR a i ʻole ka nalowale hoʻihoʻi
- Laki mua-a-hope
- Pae ʻaoʻao-lobe
- Maʻemaʻe o ka polarization
- Ka pono o ka radiation
Hāʻawi kēia hui pū ʻana o nā palena i kahi kiʻi piha loa o ka hana antenna ma mua o kahi waiwai loaʻa hoʻokahi.
Nā Pōmaikaʻi o nā Antenna Helical
Hāʻawi nā antennas helical i kekahi mau pono pono o ka ʻenekinia:
- Ke kūkulu ʻana i ka mīkini maʻalahi
- Ka hiki ke hoʻopili ʻia ke kaʻapuni kūlohelohe ma ke ʻano axial
- Ka laulā hana pono
- Hana kuhikuhi maikaʻi
- ʻO ke ʻano hoʻonui ʻia no nā pae alapine like ʻole
- Hoʻokō RHCP a i ʻole LHCP maʻalahi
- Kūpono no nā antenna pākahi a i ʻole nā hui antenna
Nā Palena Hoʻolālā
Aia kekahi mau kumu e noʻonoʻo ai:
- Pono paha nā hoʻolālā ʻano axial i ka lōʻihi kino koʻikoʻi
- ʻO ka loaʻa kiʻekiʻe e koi pinepine i nā huli hou aʻe a no laila he antenna lōʻihi
- Pili nui ka hana i ka pololei geometric
- Hoʻopili nā ana o ka honua i nā ʻano radiation
- Pono e hoʻolālā pono ʻia ka hoʻohālikelike ʻana o ka hānai
- ʻOi aku ka nui o ke kākoʻo mīkini i nā helu huli kiʻekiʻe
- Hiki i nā manaʻo circular-polarization kū'ē ke hana i ka pohō mismatch polarization kiʻekiʻe
Nā Hoʻohana Maʻamau
Hiki ke loaʻa nā antennas helical i loko o kahi ākea o nā ʻōnaehana RF, me:
- Kamaʻilio ukali
- ʻO ke telemetry a me ka hahai ʻana o nā moku lewa
- Kamaʻilio kikowaena honua
- Ka ʻike hōkū lekiō
- Nā ʻōnaehana kamaʻilio mokulele a me aerospace
- ʻO ke kelepona RF
- Nā loulou VHF a me UHF kuhikuhi
- ʻIke mamao
- Ke ana ʻana a me ka noiʻi ʻana o ka antenna
- Nā hoʻokolohua polarization pōʻai
- Ka hoʻāʻo ʻana o ka ʻōnaehana kamaʻilio
No ke aha he mea nui nā Antennas Helical i ka ʻenekinia RF
ʻO ka antenna helical kahi laʻana maikaʻi loa o ke ʻano o ka hoʻomalu ʻana o ka geometry antenna i ka hana electromagnetic.
Ma ka hoʻololi ʻana i nā palena e like me ke kaʻina, ka mamao, ke kihi pitch, a me ka helu o nā huli, hiki i nā ʻenekinia ke neʻe mai kahi radiator broadside compact i kahi antenna polarized circularly directional.
He mea nui nō hoʻi kēia pilina ma waena o ke ʻano kino a me ka hana uila i ke aʻo ʻana i nā ʻenehana antenna holomua e like me nā antenna pepeiaohao polarized circularly, nā antenna arrays, nā antennas satellite, nā antennas measurement broadband, a me nā ʻōnaehana kamaʻilio microwave.
Hoʻomohala ʻo RF MISO i nā antennas a me nā ʻāpana microwave no ka hoʻāʻo RF, kamaʻilio, radar, ana antenna, a me nā noi hoʻohui ʻōnaehana. ʻO ka hoʻomaopopo ʻana i nā ʻano antenna kumu e like me ka antenna helical e kōkua i nā ʻenekinia e loiloi maikaʻi i nā palena koʻikoʻi e pili ana i ka laulā alapine, ka loaʻa, ka polarization, ka ratio axial, ka laulā beam, VSWR, a me ke ʻano radiation.
No ka ʻike hou aku e pili ana i nā antennas, e kipa i ka pūnaewele:
Ka manawa hoʻouna: Aug-07-2026
