ʻO ka pono o kahiantennapili i ka hiki o ka antenna ke hoʻololi i ka ikehu uila komo i ka ikehu radiated.I nā kamaʻilio uila, he hopena koʻikoʻi ka hana antenna i ka maikaʻi o ka hoʻouna ʻana i nā hōʻailona a me ka hoʻohana mana.
Hiki ke hōʻike ʻia ka maikaʻi o ka antenna e kēia ʻano:
Pono = (Ka mana hoʻomālamalama / mana hoʻokomo) * 100%
Ma waena o lākou, ʻo ka mana Radiated ka ikehu electromagnetic i hoʻoheheʻe ʻia e ka antenna, a ʻo ka mana Input ka hoʻokomo ʻana i ka ikehu uila i ka antenna.
Hoʻopili ʻia ka maikaʻi o kahi antenna e nā kumu he nui, me ka hoʻolālā antenna, ka mea, ka nui, ka pinepine hana, a me nā mea maʻamau, ʻoi aku ka kiʻekiʻe o ka pono o ka antenna, ʻoi aku ka maikaʻi o ka hiki ke hoʻololi i ka ikehu uila komo i ka ikehu radiated, no laila. ka hoʻomaikaʻi ʻana i ka maikaʻi o ka hoʻouna ʻana i ka hōʻailona a me ka hōʻemi ʻana i ka hoʻohana mana.
No laila, he mea koʻikoʻi ka hoʻokō ʻana i ka hoʻolālā ʻana a me ke koho ʻana i nā antenna, ʻoi aku hoʻi i nā noi e koi ana i ka hoʻouna lōʻihi a i ʻole nā koi koʻikoʻi i ka hoʻohana ʻana i ka mana.
1. Antenna pono
![Kiʻi manaʻo o ka pono antenna](http://www.rf-miso.com/uploads/Conceptual-diagram-of-antenna-efficiency1.png)
Helu 1
Hiki ke wehewehe ʻia ka manaʻo o ka pono antenna me ka hoʻohana ʻana i ka Figure 1.
Hoʻohana ʻia ka huina antenna e0 e helu i nā poho antenna ma ka hoʻokomo a i loko o ka hoʻolālā antenna.E pili ana i ke Kiʻi 1(b), ma muli paha kēia mau poho:
1. Nā noʻonoʻo no ka like ʻole ma waena o ka laina hoʻouna a me ka antenna;
2. Nalo ka conductor a me dielectric.
Hiki ke kiʻi ʻia ka huina antenna e pono ai mai kēia ʻano kumu:
![3e0064a0af5d43324d41f9bb7c5f709](http://www.rf-miso.com/uploads/3e0064a0af5d43324d41f9bb7c5f709.png)
ʻO ia hoʻi, ka huina holoʻokoʻa = huahana o ka pono mismatch, conductor efficiency a me dielectric efficiency.
He mea paʻakikī loa ka helu ʻana i ka pono conductor a me ka pono dielectric, akā hiki ke hoʻoholo ʻia e nā hoʻokolohua.Eia naʻe, ʻaʻole hiki i nā hoʻokolohua ke hoʻokaʻawale i nā poho ʻelua, no laila hiki ke kākau hou ʻia ke ʻano o luna e like me:
![46d4f33847d7d8f29bb8a9c277e7e23](http://www.rf-miso.com/uploads/46d4f33847d7d8f29bb8a9c277e7e23-300x62.png)
ʻO ka ecd ka pono o ka radiation o ka antenna a ʻo Γ ka helu hoʻohālikelike.
2. Loaʻa a Loaʻa ʻia
ʻO kekahi metric pono no ka wehewehe ʻana i ka hana antenna ka loaʻa.ʻOiai ʻo ka loaʻa ʻana o kahi antenna e pili kokoke ana i ke kuhikuhi ʻana, he ʻāpana ia e noʻonoʻo ai i ka pono a me ke kuhikuhi ʻana o ka antenna.ʻO Directivity kahi ʻāpana e wehewehe wale i nā hiʻohiʻona kuhikuhi o kahi antenna, no laila e hoʻoholo ʻia e ke ʻano radiation wale nō.
ʻO ka loaʻa ʻana o kahi antenna ma kahi kuhikuhi i kuhikuhi ʻia ʻo "4π mau manawa o ka ratio o ka ikaika o ka radiation i kēlā ʻaoʻao i ka nui o ka mana hoʻokomo."Inā ʻaʻohe kuhikuhi i kuhikuhi ʻia, lawe ʻia ka loaʻa i ke kuhikuhi o ka radiation kiʻekiʻe.No laila, loaʻa maʻamau:
![2](http://www.rf-miso.com/uploads/2167.png)
Ma keʻano laulā, pili ia i ka waiwai pili, i wehewehe ʻia ʻo "ka ratio o ka loaʻa ʻana o ka mana i kahi kuhikuhi i kuhikuhi ʻia i ka mana o kahi antenna kuhikuhi i kahi kuhikuhi kuhikuhi".Pono e like ka mana hookomo i keia antenna.Hiki i ka antenna kuhikuhi ke lilo i vibrator, horn a i ʻole antenna ʻē aʻe.I ka hapanui o nā hihia, hoʻohana ʻia kahi kumu kuhikuhi ʻole e like me ka antenna kuhikuhi.No laila:
![3](http://www.rf-miso.com/uploads/3163.png)
ʻO ka pilina ma waena o ka mana radiated a me ka mana hoʻokomo piha penei:
![0c4a8b9b008dd361dd0d77e83779345](http://www.rf-miso.com/uploads/0c4a8b9b008dd361dd0d77e83779345.png)
Wahi a ka IEEE maʻamau, "ʻAʻole komo ka loaʻa i nā poho ma muli o ka impedance mismatch (reflection loss) a me ka polarization mismatch (loss)."ʻElua mau manaʻo waiwai, kapa ʻia kekahi gain (G) a ʻo kekahi i kapa ʻia ʻo achievable gain (Gre), e noʻonoʻo ana i nā poho noʻonoʻo/mismatch.
ʻO ka pilina ma waena o ka loaʻa a me ka pololei:
![4](http://www.rf-miso.com/uploads/4142.png)
![5](http://www.rf-miso.com/uploads/5114.png)
Inā pili pono ka antenna i ka laina hoʻouna, ʻo ia hoʻi, ua like ka antenna input impedance Zin me ka impedance hiʻona Zc o ka laina (|Γ| = 0), a laila ua like ka loaʻa a me ka loaʻa ʻana (Gre = G. ).
No ka ʻike hou aku e pili ana i nā antenna, e kipa:
![](/wp-content/plugins/bb-plugin/img/pixel.png)
Ka manawa hoʻouna: Iune-14-2024