Menene Antenna Mai Helical?
Eriya mai siffar helical, wacce aka fi sani da eriya mai siffar helix, eriya ce ta waya da aka samar ta hanyar naɗe waya ko bututu mai juyi zuwa cikin helix mai girma uku. Ɗayan ƙarshen helix yawanci ana haɗa shi da mai juyi na tsakiya na layin ciyarwa, yayin da mai juyi na waje yana haɗuwa da wani ƙarfe na ƙasa ko mai nuna haske.
Tsarin halittarsa na musamman yana bawa eriya damar aiki a cikin yanayin radiation daban-daban dangane da alaƙar da ke tsakanin girman helix da tsawon aikin.
Daga cikin waɗannan hanyoyin,yanayin axialyana da matuƙar muhimmanci a fannin injiniyan RF da microwave domin yana iya samar da hasken da ke fuskantar hanya, faɗin bandwidth, da kuma rarrabawar zagaye. Waɗannan halaye suna sa eriya masu helical su zama masu amfani a hanyoyin haɗin tauraron ɗan adam, na'urar hangen nesa, bin diddigi, sadarwa ta sararin samaniya, ilmin taurari na rediyo, da sauran aikace-aikace inda yanayin eriya zai iya canzawa.
Mitar aiki ta eriya mai siffar helical ba ta takaita ga wani tsayayyen madauri ɗaya ba. Madadin haka, galibi ana tantance ta ne ta hanyar girmanta na zahiri dangane da tsawon tsayi. Saboda haka, ana iya tsara tsarin helical don tsarin VHF da UHF da kuma aikace-aikacen RF mai yawan mita da microwave.
Hoto na 1. Misalin eriya mai siffar helical da ake amfani da su a tsarin sadarwa na alkibla.
Tsarin Asali na Antenna Mai Helical
Eriya mai siffar helical ta yau da kullun ta ƙunshi manyan sassa huɗu:
- Mai jagora mai helikafta
- Na'urar haskaka ƙasa ko na'urar haskakawa
- Wurin ciyar da RF
- Tsarin tallafin injina
Helix yawanci ana yin sa ne da wayar jan ƙarfe, bututu, ko wani abu mai sarrafa wutar lantarki. Ɗayan ƙarshen yana da alaƙa da mai sarrafa wutar lantarki na tsakiyar layin watsa wutar lantarki, yayin da mai sarrafa wutar lantarki na waje yana da alaƙa da ƙasa.
Tsarin ƙasa yana taimakawa wajen sarrafa alkiblar hasken kuma yana aiki a matsayin wani ɓangare na tsarin ciyar da eriya. A cikin ƙira mai amfani, girmansa na iya yin tasiri sosai ga juriya, aikin gaba-da-baya, da kuma tsarin hasken da ya haifar.
Sigogi da dama na lissafi suna tantance yanayin lantarki na eriya:
- D - Diamita na Helix
- C - Da'irar juyawa ɗaya
- S - Tazara tsakanin juyawar da ke kusa
- N - Adadin juyawa
- α - Kusurwar firam
- L - Jimlar tsawon axial
Da'irar ita ce:
[C=\pi D]
Ana iya bayyana kusurwar faɗakarwa kamar haka:
[\alpha=\tan^{-1}\left(\frac{S}{\pi D}\right)]
Ba za a iya la'akari da waɗannan sigogi daban-daban ba saboda canza girma ɗaya yana canza juriyar eriya, polarization, beamwidth, riba, da mitar aiki.
Hoto na 2. Tsarin eriya mai siffar helical tare da jagorar helix da kuma na'urar haskaka ƙasa.
Manyan Hanyoyi Biyu na Radiation
Ɗaya daga cikin halaye mafi ban sha'awa na eriya mai siffar helical shine cewa tsarin asali ɗaya zai iya samar da nau'ikan radiation daban-daban dangane da girman wutar lantarki.
Hanyoyi biyu da ake yawan magana a kansu su ne:
- Yanayin al'ada
- Yanayin axial
Fahimtar bambancin da ke tsakanin waɗannan hanyoyi guda biyu yana da mahimmanci yayin zaɓar ko tsara eriya mai siffar helical.
Eriya Mai Sauƙi ta Al'ada
In yanayin al'ada, jimlar diamita da tazara tsakanin helix ɗin ƙanana ne idan aka kwatanta da tsawon igiyar.
Ana mayar da hasken rana kusan daidai da axis ɗin helix maimakon a kan shi. Ana iya fahimtar halayen lantarki a matsayin haɗuwar filayen da aka samar ta hanyar ɗan gajeren dipole na lantarki da ƙaramin madauki.
Dangane da yanayin helix, kusurwar siffa, tsarin ciyarwa, da kuma alkiblar lura, rabuwar da ke haifarwa na iya zama layi, elliptical, ko kuma a wasu ƙira kusa da zagaye.
Helice na yanayin al'ada yawanci suna da ƙanƙanta, amma ƙananan girmansu na lantarki yana haifar da ƙarancin juriya ga radiation. Wannan na iya haifar da ƙarancin ingancin radiation da ƙarancin bandwidth fiye da ƙirar yanayin axial.
Saboda haka suna da amfani idan girman eriya babban cikas ne kuma ba a buƙatar babban riba.
Hoto na 3. Tsarin hasken da aka kwatanta na eriya mai siffar helical ta al'ada.
Antenar Helical ta Axial-Mode
Theyanayin axial, wanda wani lokacin ake kira yanayin ƙarewa, shine tsarin da aka fi dangantawa da eriya mai ƙarfin aiki.
A wannan yanayin, makamashin lantarki yana haskakawa galibi a kan axis na helix, yana samar da hasken da ke jagora.
Tsarin yanayin axial na yau da kullun yana amfani da kewayen helix wanda yayi daidai da tsawon tsayi ɗaya:
[C \kimanin \lambda]
Tazarar juyawa sau da yawa tana kusa da:
[S \approx 0.2\lambda \text{ zuwa } 0.3\lambda]
tare da kusan rabin zangon raƙuman ruwa na kwata shine wurin farawa na gama gari.
Ga yawancin ƙirar yanayin axial na gargajiya, ana yawan amfani da kusurwoyin kusurwa kusa da 12°–14°.
A ƙarƙashin yanayin siffofi masu dacewa, filayen da aka samar ta hanyar juyawa a jere suna haɗuwa ta hanyar gini tare da ma'aunin helix. Wannan yana samar da hasken alkibla tare da rarrabawa da'ira ko kusa da da'ira.
Adadin juyawa kuma yana shafar aikin eriya. Ƙara yawan juyawa gabaɗaya na iya ƙara ƙarfin kai tsaye da ƙaruwa yayin da yake rage babban hasken, kodayake ƙira masu amfani dole ne su yi la'akari da tsawon injina, asarar jagoran jagora, daidaita juriya, da ƙuntatawa na shigarwa.
Hoto na 4. Tsarin hasken eriya mai siffar axial-mode mai kama da helical tare da babban hasken alkibla.
Rarrabuwar Zagaye ta Hannun Dama da Hagu
Ɗaya daga cikin manyan fa'idodin eriya mai siffar helical ta axial shine ikonta na halitta na samar da rabuwar zagaye.
Dangane da alkiblar juyawa da kuma alkiblar radiation, ana iya tsara helix don samar da ko dai:
- RHCP — Rarraba Zagaye na Hannun Dama
- LHCP — Rarraba Zagaye na Hagu da Hagu
Polarization na zagaye yana da amfani musamman idan yanayin da ke tsakanin eriya mai watsawa da mai karɓa ba zai iya kasancewa a tsaye ba.
Misali, tauraron dan adam, jiragen sama masu saukar ungulu, dandamalin sama, tsarin juyawa, da kayan aikin sadarwa na wayar hannu na iya ci gaba da canza yanayinsu. Eriya mai zagaye mai rabewa na iya rage saurin haɗin sadarwa zuwa wannan bambancin kusurwa.
Daidaitawar rabuwar ƙasa har yanzu yana da mahimmanci. Eriya ta RHCP ta fi dacewa ta yi mu'amala da eriya ta RHCP, yayin da eriya ta LHCP ya kamata a haɗa ta da eriya ta LHCP. Rarrabawar rabuwar ƙasa mai kusurwa biyu na iya haifar da asarar rabuwar ƙasa mai yawa.
Don kimantawar injiniya,rabon axialana amfani da shi akai-akai don bayyana ingancin juyawar da'ira. Kyakkyawan raƙuman da'ira masu juyawar da'ira suna da rabon axial na 0 dB, yayin da ake kimanta eriya masu juyawar da'ira masu juyawar da'ira akan takamaiman buƙatun rabon axial a cikin mita da kewayon kusurwa da ake so.
Abubuwan da ke Shafar Aikin Antenna na Helical
Halin eriya mai siffar helical yana da alaƙa da yanayinta.
Muhimman sigogin ƙira sun haɗa da:
Da'irar Helix
Alaƙar da ke tsakanin kewaye da tsawon tsayin igiyar ruwa tana taka muhimmiyar rawa wajen tantance ko eriya tana aiki a yanayin da aka saba ko yanayin axial.
Juya Tazara
Tazara tana shafar dangantakar da ke tsakanin kwararar ruwa a kan juyawar da ke kusa da ita, don haka tana shafar alkiblar hasken rana, juriya, da kuma rabuwar haske.
Kusurwar Fitilar
Kusurwar siffa ta bayyana yadda helix ke tafiya da sauri a kan axis ɗinsa. Yana da ma'auni mai mahimmanci don kiyaye yanayin yanayin axial mai ɗorewa.
Adadin Juyawa
Yawancin juyawa gabaɗaya suna ƙara buɗewar lantarki kuma suna iya samar da mafi girman kai tsaye, amma kuma suna ƙara tsawon eriya da sarkakiyar injiniya.
Jirgin Ƙasa
Girman da siffar mai haskakawa suna tasiri ga tsarin hasken gaba, juriya, da kuma hasken baya.
Daidaita Ciyarwa da Impedance
Ko da tare da daidaitaccen girman helix, rashin daidaituwar impedance na iya ƙara ƙarfin da aka nuna da kuma rage aikin eriya da aka samu. Saboda haka, ƙira masu amfani suna buƙatar kimanta asarar dawowa ko VSWR tare da halayen radiation.
Tsarin Haske da Samun Radiation
A yanayin axial, eriya mai siffar helical tana samar da babban katako mai tsayi a tsakiya kusan axis ɗin helix.
Yayin da tsawon wutar lantarki da adadin juyawa ke ƙaruwa, babban hasken gaba ɗaya yana ƙara zama kunkuntar kuma ƙarfin eriya yana ƙaruwa. Lobes na gefe kuma na iya bayyana, musamman a cikin tsarukan da ba a inganta su ba ko kuma a cikin gine-gine masu tsayi.
Saboda haka, bai kamata a kimanta eriya ta hanyar riba kawai ba. Injiniyoyi yawanci suna la'akari da halaye da yawa tare:
- Riba
- Ribar da aka samu
- Faɗin rabin ƙarfin haske
- Rabon axial
- VSWR ko asarar dawowa
- Rabon gaba-da-baya
- Matakin gefe-gefe
- Tsarkakewar rabuwar ƙasa
- Ingancin radiation
Wannan haɗin sigogi yana ba da cikakken hoto na aikin eriya fiye da ƙimar riba ɗaya.
Fa'idodin Antennas na Helical
Antennas na helical suna ba da fa'idodi da yawa na injiniya masu amfani:
- Tsarin injiniya mai sauƙi
- Ƙarfin rarrabawar yanayi na dabi'a a yanayin axial
- Amfani da bandwidth mai aiki
- Kyakkyawan aikin alkibla
- Tsarin lissafi mai iya canzawa don kewayon mita daban-daban
- Aiwatar da RHCP mai sassauƙa ko LHCP
- Ya dace da eriya ɗaya ko jerin eriya
Iyakokin Zane
Akwai kuma abubuwa da dama da za a yi la'akari da su:
- Tsarin yanayin axial na iya buƙatar dogon jiki mai mahimmanci
- Babban riba yawanci yana buƙatar ƙarin juyawa don haka eriya mai tsayi
- Aiki ya dogara sosai akan daidaiton lissafi
- Girman ƙasa yana tasiri ga halayen radiation
- Dole ne a tsara yadda ya kamata a daidaita abincin da aka ciyar
- Tallafin injina ya zama mafi mahimmanci a mafi yawan adadin juyawa
- Ma'anar da ke tsakanin ma'aunin polarization da zagaye na iya haifar da babban asarar rashin daidaiton polarization
Aikace-aikace na yau da kullun
Ana iya samun eriya mai siffar helical a cikin tsarin RF iri-iri, gami da:
- Sadarwar tauraron dan adam
- Tsarin aiki da bin diddigin sararin samaniya
- Sadarwar tashar ƙasa
- Tauraron taurari na rediyo
- Tsarin sadarwa na jiragen sama da na sararin samaniya
- Tsarin RF
- Hanyoyin VHF da UHF na alkibla
- Ganowa daga nesa
- Aunawa da bincike na eriya
- Gwaje-gwajen da'ira-polarization
- Gwajin tsarin sadarwa
Dalilin da yasa Antennas na Helical suke da mahimmanci a Injiniyan RF
Eriya mai siffar helical misali ne mai kyau na yadda tsarin eriya ke sarrafa halayen lantarki.
Ta hanyar canza sigogi kamar kewaye, tazara, kusurwar juyawa, da adadin juyawa, injiniyoyi za su iya canzawa daga ƙaramin radiator mai faɗi zuwa eriya mai zagaye mai juyawa.
Wannan alaƙar da ke tsakanin yanayin zahiri da aikin lantarki tana da mahimmanci yayin nazarin fasahohin eriya masu ci gaba kamar eriya masu ƙaho mai zagaye, jerin eriya, eriya ta tauraron ɗan adam, eriya mai auna broadband, da tsarin sadarwa na microwave.
RF MISO tana haɓaka eriya da abubuwan da ke cikin microwave don gwajin RF, sadarwa, radar, auna eriya, da aikace-aikacen haɗa tsarin. Fahimtar mahimman tsarin eriya kamar eriya mai helical yana taimaka wa injiniyoyi su kimanta mahimman sigogi waɗanda suka haɗa da kewayon mita, riba, polarization, axial ratio, beamwidth, VSWR, da tsarin radiation.
Don ƙarin koyo game da eriya, da fatan za a ziyarci:
Lokacin Saƙo: Agusta-07-2026
