Gịnị bụ Antenna Helical?
Antenna helical, nke a makwaara dị ka antenna helix, bụ antenna waya nke e ji waya ma ọ bụ tube na-eduzi mee ka ọ bụrụ helix nwere akụkụ atọ. Otu nsọtụ nke helix na-ejikọkarị na onye na-eduzi etiti nke ahịrị nri, ebe onye na-eduzi mpụta na-ejikọ na mbara ala ígwè ma ọ bụ ihe na-egosipụta ihe.
Ọdịdị ya pụrụ iche na-enye ohere ka antenna rụọ ọrụ n'ụdị radieshon dị iche iche dabere na mmekọrịta dị n'etiti akụkụ helix na ogologo ebili mmiri ọrụ.
N'ime usoro ndị a,ụdị axialdị oke mkpa na injinịa RF na microwave n'ihi na ọ nwere ike inye radieshon ntụziaka, bandwit sara mbara, na polarization gburugburu. Àgwà ndị a na-eme ka antenna helical baa uru na njikọ satịlaịtị, telemetry, tracking, space communication, radio astronomy, na ngwa ndị ọzọ ebe nhazi antenna nwere ike ịgbanwe.
Ugboro ọrụ nke antenna helical abụghị naanị otu eriri edobere. Kama, a na-ekpebi ya site na nha anụ ahụ ya ma e jiri ya tụnyere ogologo ebili mmiri. Ya mere, enwere ike ịmepụta usoro helical maka sistemụ VHF na UHF yana RF ugboro ugboro na ngwa microwave.
Foto 1. Ihe atụ nke antenna helical eji eme ihe na sistemụ nkwukọrịta ntụziaka.
Nhazi Isi nke Antena Helical
Antenna helical nkịtị nwere akụkụ anọ bụ isi:
- Onye nduzi helikọpta
- Ala ma ọ bụ ihe ngosiputa
- Ebe ntinye RF
- Nhazi nkwado igwe
A na-ejikarị waya ọla kọpa, ọkpọkọ, ma ọ bụ ihe ọzọ na-eduzi helix eme ihe. A na-ejikọ otu nsọtụ na onye na-eduzi etiti nke eriri nnyefe coaxial, ebe onye na-eduzi mpụga coaxial jikọtara ya na ala eletrik.
Ala elu ahụ na-enyere aka ijikwa ntụziaka radieshọn ma na-arụ ọrụ dịka akụkụ nke usoro nri antenna. N'ime atụmatụ bara uru, nha ya nwere ike imetụta impedance nke ukwuu, arụmọrụ ihu na azụ, na ụkpụrụ radieshọn na-esi na ya apụta.
Ọtụtụ paramita geometric na-ekpebi omume eletriki nke antenna:
- D — Dayameta helix
- C - Gburugburu otu ntụgharị
- S - Oghere dị n'etiti ntụgharị dị n'akụkụ
- N — Ọnụọgụ nke ntụgharị
- α — Nkuku pitch
- L - Ngụkọta ogologo axial
Gburugburu ahụ bụ:
[C=\pi D]
Enwere ike ịkọwa akụkụ pitch dị ka:
[\alpha=\tan^{-1}\left(\frac{S}{\pi D}\right)]
Enweghị ike ịtụle paramita ndị a n'adabereghị n'otu n'otu n'ihi na ịgbanwe otu akụkụ na-agbanwe impedance nke antenna, polarization, beamwidth, gain, na ugboro ọrụ.
Foto nke 2. Ọdịdị antenna helical nkịtị nwere onye na-eduzi helix na onye na-egosipụta ala.
Ụdị Radiation Abụọ Isi
Otu n'ime ihe ndị kacha atọ ụtọ gbasara antenna helical bụ na otu nhazi ahụ nwere ike imepụta ụdị radieshon dị iche iche dabere na nha eletriki ya.
Ụdị ọrụ abụọ a na-ekwukarị bụ:
- Ụdị nkịtị
- Ụdị Axial
Ịghọta ọdịiche dị n'etiti ụdịdị abụọ a dị mkpa mgbe ị na-ahọrọ ma ọ bụ na-emepụta antenna helical.
Antenna Helical nkịtị
In ọnọdụ nkịtị, dayameta na oghere zuru oke nke helix pere mpe ma e jiri ya tụnyere ogologo ebili mmiri.
A na-eduzi radieshọn dịka ihe dị ka n'akụkụ nke helix kama n'akụkụ ya. Enwere ike ịghọta omume elektrọnik dị ka njikọta nke ubi ndị a na-emepụta site na obere dipole eletriki na obere loop.
Dabere na ọdịdị helix, akụkụ pitch, nhazi nri, na ntụziaka nlele, polarization sitere na ya nwere ike ịbụ ahịrị, elliptical, ma ọ bụ n'ụdị ụfọdụ dị nso na okirikiri.
Helisi ụdị nkịtị na-adịkarị obere, mana obere akụkụ ha n'ihi ọkụ eletrik na-eme ka ha ghara iguzogide radieshon. Nke a nwere ike ibute obere arụmọrụ radieshon na obere bandwidth karịa imewe ụdị axial.
Ya mere, ha bara uru mgbe nha antenna bụ nnukwu ihe mgbochi na ọ dịghị mkpa ka e nweta nnukwu uru.
Foto nke 3. Ihe atụ nke usoro radieshọn nke antenna helical nke ụdị nkịtị.
Antenna Helical nke Ụdị Axial
Iheụdị axial, nke a na-akpọ mgbe ụfọdụ ọnọdụ njedebe-ọkụ, bụ nhazi a na-ejikarị eme ihe na antenna helical dị elu.
N'ụdị a, ike elektrọnik na-agbasakarị n'akụkụ axis nke helix, na-emepụta ìhè ntụziaka.
Nhazi ụdị axial a na-ejikarị okirikiri helix dị ka otu ogologo ebili mmiri:
[C \ihe dị ka \lambda]
Ogologo ntụgharị na-adịkarị gburugburu:
[S \approx 0.2\lambda \text{ to } 0.3\lambda]
ebe ihe dị ka otu ụzọ n'ụzọ anọ nke ogologo ebili mmiri bụ ebe mmalite a na-ahụkarị.
Maka ọtụtụ nhazi ụdị axial a na-emekarị, a na-ejikarị akụkụ pitch gburugburu 12°–14° eme ihe.
N'okpuru ọnọdụ geometric kwesịrị ekwesị, ubi ndị a na-emepụta site na ntụgharị ndị na-esochi na-ejikọta ọnụ n'akụkụ helix. Nke a na-emepụta ogwe ntụaka yana polarization gburugburu ma ọ bụ nke dị nso gburugburu.
Ọnụọgụ ntụgharị na-emetụtakwa arụmọrụ antenna. Ịba ụba ọnụọgụ ntụgharị nwere ike ime ka nduzi na uru dịkwuo elu ebe ọ na-ebelata nnukwu ogwe osisi ahụ, ọ bụ ezie na imewe bara uru ga-atụlekwa ogologo igwe, mfu onye na-eduzi ya, njikọ mgbochi, na mmachi nrụnye.
Foto nke 4. Ụkpụrụ radieshọn antenna helical nke nwere ụdị axial-mode nwere ìhè isi nke na-eduzi.
Mgbasa okirikiri nke aka nri na aka ekpe
Otu n'ime uru dị na antenna helical nke ụdị axial bụ ikike ebumpụta ụwa ya ịmepụta polarization gburugburu.
Dabere na ntụziaka ntụgharị na ntụziaka radieshon, enwere ike ịmepụta helix iji mepụta otu n'ime ihe ndị a:
- RHCP — Mgbasa okirikiri nke aka nri
- LHCP — Mgbawa okirikiri nke aka ekpe
Mgbasa okirikiri bara uru karịsịa mgbe njikọ dị n'etiti antenna nnyefe na nke nnata enweghị ike ịnọgide na-edozi.
Dịka ọmụmaatụ, satịlaịtị, ụgbọelu mbara igwe, ikpo okwu ikuku, sistemụ na-agbagharị agbagharị, na ngwa nkwukọrịta mkpanaka nwere ike ịgbanwe ọnọdụ ha mgbe niile. Antenna gbara okirikiri nwere ike ibelata mmetụta nke njikọ nkwukọrịta na mgbanwe akụkụ a.
Nhazi nke polarization ka dị mkpa. Antena RHCP na-ejikọ nke ọma na antena RHCP, ebe a na-ejikọ antena LHCP na antena LHCP. Polarizations gburugburu dị n'akụkụ nke ọzọ nwere ike ibute nnukwu mfu polarization.
Maka nyocha injinia,oke axialA na-ejikarị ya akọwa àgwà nke ịgba okirikiri na polarization. Ebili mmiri gbara okirikiri nke ọma nwere oke axial nke 0 dB, ebe a na-enyocha antenna ndị gbara okirikiri nke ọma dabere na ihe achọrọ maka oke axial na oke axis n'ofe ugboro na oke angle achọrọ.
Ihe Ndị Na-emetụta Arụmọrụ Antenna Helical
Omume nke antenna helical nwere njikọ chiri anya na ọdịdị ya.
Ihe dị mkpa e ji hazie ihe gụnyere:
Gburugburu Helix
Mmekọrịta dị n'etiti gburugburu na ogologo ebili mmiri na-arụ ọrụ dị mkpa n'ịchọpụta ma antenna ahụ na-arụ ọrụ n'ụdị nkịtị ma ọ bụ n'ụdị axial.
Oghere ntụgharị
Oghere na-emetụta mmekọrịta dị n'etiti ọkụ eletrik na ntụgharị dị n'akụkụ ya, ya mere ọ na-emetụta ntụziaka ìhè, mgbochi, na polarisation.
Akụkụ Pitch
Akụkụ olu na-akọwa etu helix si aga n'ihu ngwa ngwa n'akụkụ ya. Ọ bụ paramita dị mkpa maka ịnọgide na-enwe omume ọnọdụ axial kwụsiri ike.
Ọnụọgụ nke ntụgharị
Ọtụtụ ntụgharị na-eme ka oghere eletriki dịkwuo elu ma nwee ike inye nduzi dị elu, mana ha na-emekwa ka ogologo antenna na mgbagwoju anya igwe dịkwuo elu.
Ụgbọelu Ala
Nha na ọdịdị nke ihe na-egosipụta ìhè na-emetụta ụdị radieshon n'ihu, impedance, na radieshon azụ.
Ndakọrịta Nri na Impedance
Ọ bụrụgodị na e nwere nha helix ziri ezi, njikọ impedance na-adịghị mma nwere ike ime ka ike a na-egosipụta dịkwuo elu ma belata arụmọrụ antenna a na-ahụ anya. Ya mere, atụmatụ ndị bara uru kwesịrị ịtụle mfu nloghachi ma ọ bụ VSWR yana njirimara radieshon.
Ụkpụrụ na Uru Radiation
N'ụdị axial, antenna helical na-emepụta nnukwu ogwe osisi nke dị n'etiti ihe dị ka akụkụ helix.
Ka ogologo na ọnụọgụ nke ntụgharị eletriki na-abawanye, nnukwu ọkụ na-adịkarị warara ma usoro antenna na-abawanye. Akụkụ akụkụ nwekwara ike ịpụta, ọkachasị n'ime ụlọ ndị dị ogologo ma ọ bụ ndị na-anaghị arụ ọrụ nke ọma.
Ya mere, ekwesighi iji uru naanị ya nyochaa antenna ahụ. Ndị injinia na-atụlekarị ọtụtụ njirimara ọnụ:
- Uru
- Uru enwetara
- Ọkara ike ìhè
- Oke axial
- Mfu VSWR ma ọ bụ nloghachi
- Oke ihu na azụ
- Ọkwa akụkụ-lobe
- Ịdị ọcha nke polarization
- Arụmọrụ radieshọn
Njikọta paramita a na-enye nkọwa zuru oke nke arụmọrụ antenna karịa uru uru otu.
Uru nke Helical Antennas
Antenna helical na-enye ọtụtụ uru injinia bara uru:
- Nrụpụta igwe dị mfe
- Ike polarization gburugburu eke na ọnọdụ axial
- Bandwit ọrụ bara uru
- Arụmọrụ ntụziaka dị mma
- Geometry a na-agbanwe agbanwe maka oke ugboro dị iche iche
- Mmejuputa RHCP ma ọ bụ LHCP na-agbanwe agbanwe
- Dabara adaba maka antenna nke ọ bụla ma ọ bụ usoro antenna
Mmachi Nhazi
E nwekwara ọtụtụ ihe ị ga-atụle:
- Nhazi ụdị Axial nwere ike ịchọ ogologo anụ ahụ dị oke mkpa
- Uru dị elu na-achọkarị ntụgharị karịa, ya mere antenna dị ogologo
- Arụmọrụ dabere nke ọma na izi ezi nke geometric
- Akụkụ ala na-emetụta njirimara radieshon
- A ga-ahazi nhazi nri nke ọma
- Nkwado igwe na-aghọ ihe dị mkpa karịa na ọnụọgụgụ ntụgharị dị elu
- Mmetụta polarization gburugburu dị iche iche nwere ike ịkpata mfu enweghị nkwekọ polarization dị elu
Ngwa Ndị A Na-ahụkarị
Enwere ike ịchọta antenna helical n'ọtụtụ sistemụ RF dị iche iche, gụnyere:
- Nkwukọrịta satịlaịtị
- Telemetry na nsochi ụgbọ elu mbara igwe
- Nkwukọrịta n'ọdụ ala
- Nkà mmụta mbara igwe redio
- Sistemụ nkwukọrịta ikuku na nke ikuku
- Telemetry RF
- Njikọ VHF na UHF ntụziaka
- Nchọpụta dịpụrụ adịpụ
- Ntụle na nyocha nke antenna
- Nnwale okirikiri-polarization
- Nnwale sistemụ nkwukọrịta
Ihe kpatara Helical Antennas ji dị mkpa na Injinịa RF
Antenna helical bụ ezigbo ihe atụ nke otu geometry antenna si achịkwa omume elektrọnik.
Site n'ịgbanwe paramita dịka okirikiri, oghere, akụkụ pitch, na ọnụọgụ nke ntụgharị, ndị injinia nwere ike ịkwaga site na obere radiator sara mbara gaa na antenna okirikiri nke nwere polar gburugburu.
Mmekọrịta a dị n'etiti geometry anụ ahụ na arụmọrụ eletriki dịkwa mkpa mgbe a na-amụ teknụzụ antenna ndị ka elu dịka antenna mpi gburugburu, antenna arrays, antenna satịlaịtị, antenna nha broadband, na sistemụ nkwukọrịta microwave.
RF MISO na-emepụta antenna na ihe ndị dị na microwave maka nnwale RF, nkwukọrịta, radar, nha antenna, na ngwa njikọta sistemụ. Ịghọta usoro antenna dị mkpa dịka antenna helical na-enyere ndị injinia aka inyocha paramita dị mkpa nke ọma gụnyere oke ugboro, uru, polarization, axial ratio, beamwidth, VSWR, na ụkpụrụ radieshon.
Iji mụtakwuo maka antenna, biko gaa na:
Oge ozi: Ọgọst-07-2026
