Izindaba - I-Helical Antenna: Ukukhetha Okuhle Kokuhlukaniswa Kwesiyingi Se-Broadband – Kusukela Ku-Theory Kuya Kuzinhlelo Zokusebenza

AI-Antenna Ejikelezayoiyisibonelo esivamile se-antenna yocingo, ebonakala ngesakhiwo sayo esimise okwesiyingi. Iyi-antenna ye-broadband efanelekela ama-VHF nama-UHF band.

I-antenna ejikelezayo isebenza ngaphezu kwebanga lemvamisa elicishe libe ngu-30 MHz kuya ku-3 GHz, ikakhulukazi imboza ama-VHF kanye nama-UHF band.

Izimiso Zokwakha Nokusebenza ze-Spiral Antenna

I-Spiral Antenna yakhiwa ngokugoqa umqhubi abe yisimo esijikelezayo bese uyixhuma endizeni yomhlabathi nge-feedline. Ngesakhiwo esilula, ikhiqiza ngokwemvelo amagagasi ahlukaniswe ngendilinga futhi isetshenziswa kabanzi ekuxhumaneni kwangaphandle komhlaba njengezinhlelo zokudlulisa amasathelayithi.

Isithombe esingenhla sibonisa uhlelo lwe-Spiral Antenna olusetshenziselwa ukuxhumana ngesathelayithi. Ama-antenna anjalo ngokuvamile adinga isikhala esanele sokufakwa ngaphandle.

I-Spiral Antenna yakhiwe yi-coil yocingo lwethusi olujiyile noma ipayipi elakhiwe nge-helix, elisebenza ngokubambisana ne-ground plane yensimbi eyisicaba. Ukuphela kwe-helix kuxhunywe ku-coaxial cable ephakathi nendawo, kuyilapho i-coaxial yangaphandle ixhunywe ku-ground plane.

Isithombe esingenhla sibonisa isakhiwo se-Spiral Antenna, ngombono oningiliziwe wezingxenye zayo.

Izici zokukhanya kwe-Spiral Antenna zinqunywa kakhulu ububanzi be-helix, isikhala esiphakathi kokujika (iphimbo), kanye ne-angle yephimbo.

I-angle yephimbo ichazwa njenge-angle ephakathi kwe-tangent kuya ku-helix kanye nendiza evamile ku-axis ye-helix, futhi inikezwa yi:

Kuphi:

•U-D ububanzi be-helix

•S yi-pitch (isikhala esiphakathi nendawo phakathi kokujika okuseduze)

•α yi-engeli yephimbo

Imodi Yokusebenza

Ama-Antenna ajikelezayo asebenza ngezindlela ezimbili eziyinhloko:

•Imodi Ejwayelekile (eyaziwa nangokuthi imodi yemisebe eqondile)

•Imodi ye-Axial (eyaziwa nangokuthi imodi yokuphela komlilo noma imodi yokukhanya kwe-beam)

Imodi ngayinye ichazwe ngokuningiliziwe ngezansi.

Kwimodi yokukhanya evamile, insimu ekhanyayo iqonde ngqo ku-axis ye-helix, kanti igagasi elikhanyayo lijikeleza ngokujikeleza. Le modi ifinyelelwa lapho ubukhulu be-helix buncane uma buqhathaniswa nobude be-wavelength. Kulokhu, izici zokukhanya ze-antenna ye-helical zingabhekwa njengenhlanganisela ye-antenna emfushane ye-dipole kanye ne-antenna ye-loop.

Isithombe esingenhla sibonisa iphethini yemisebe ye-Spiral Antenna esebenza ngendlela evamile.

Le modi inqunywa ububanzi be-helix D kanye nesikhala phakathi kokujika kuka-S. Okubi kwale modi yokusebenza kufaka phakathi ukusebenza kahle kwemisebe ephansi kanye nomkhawulokudonsa omncane; ngakho-ke, ayisetshenziswa kakhulu ezisetshenziswayo ezingokoqobo.

Imodi ye-Axial

Kumodi yemisebe ye-axial, insimu ekhishwa imisebe ibonisa izici zomlilo wokuphela eceleni kwe-axis ye-helix, kanti igagasi elikhishwa imisebe lihlukaniswe ngokuzungeza noma cishe ngokuzungeza. Le modi ifinyelelwa lapho umjikelezo we-helix ukhuliswa ukuya ku-oda lobude obulodwa (λ) futhi isikhala phakathi kokujika cishe singu-λ/4. Ngaphansi kwalezi zimo, iphethini yemisebe ibanzi eceleni kwe-axis enezimpawu zokuqondisa, futhi ama-lobe aseceleni avela kuma-engeli ahlukene ne-axis.

Isithombe esingenhla sibonisa iphethini yemisebe ye-Spiral Antenna esebenza kwimodi ye-axial.

Uma i-antenna iklanyelwe amagagasi ajikelezwe yi-circularly polarized (RHCP) kwesokudla, ngeke ithole amagagasi ajikelezwe yi-circularly polarized (LHCP) ngakwesokunxele, futhi okuphambene nalokho. Le ndlela yokusebenza kulula ukuyisebenzisa futhi isetshenziswa kakhulu ezinhlotsheni ezisebenzayo.

Izinzuzo eziyinhloko ze-Spiral Antenna yilezi ezilandelayo:

• Isakhiwo esilula futhi kulula ukusiklama

•Isiqondiso Esiphezulu

•Umkhawulokudonsa obanzi

•Iyakwazi ukuhlukaniswa okujikelezayo

•Kufanelekela amabhendi e-HF ne-VHF

Izicelo eziyinhloko ze-Spiral Antenna yilezi ezilandelayo:

•Ama-antenna ajikelezayo noma ama-array awo asetshenziselwa ukudlulisa nokwamukela isignali ye-VHF

•Kusetshenziswa kabanzi ezinhlelweni zokuxhumana zesathelayithi kanye ne-deep-space probe

•Kusetshenziswa ekuxhumaneni kwe-telemetry phakathi kwemicibisholo ye-ballistic, amasathelayithi, kanye neziteshi zomhlaba

•Isetshenziselwa ukusungula ukuxhumana phakathi kweNyanga noMhlaba

•Iphinde idlale indima ebalulekile ekusetshenzisweni kwezinkanyezi zomsakazo