Polarization bụ otu n'ime njirimara bụ isi nke antennas. Anyị kwesịrị ibu ụzọ ghọta polarization nke ebili mmiri ụgbọ elu. Anyị nwere ike kparịta ụdị isi nke polarization antenna.
linear polarization
Anyị ga-amalite ịghọta polarization nke ụgbọ elu electromagnetic ife.
Igwe ọkụ eletrik nke planar (EM) nwere ọtụtụ njirimara. Nke mbụ bụ na ike na-aga n'otu ụzọ (ọ dịghị ubi na-agbanwe na ụzọ abụọ orthogonal). Nke abụọ, ọkụ eletrik na oghere magnetik na-adabere na ibe ya na orthogonal na ibe ya. Ebe eletriki na magnetik na-adabere na ntụzịaka nke ifegharị ụgbọ elu. Dịka ọmụmaatụ, tụlee otu mpaghara ọkụ eletrik otu ugboro (E ubi) nyere site na nhata (1). Ebe electromagnetic na-aga na ntụzịaka +z. A na-eduzi mpaghara eletrik na ntụzịaka +x. Ebe ndọta dị na ntụzịaka +y.
Na nhata (1), debe akara ngosi: . Nke a bụ vector unit (a vector nke ogologo), nke na-ekwu na ebe ọkụ eletrik dị na ntụziaka x. E gosipụtara ife ụgbọ elu na eserese 1.
ọnụ ọgụgụ 1. Ihe ngosi eserese nke mpaghara eletrik na-eme njem na ntụziaka +z.
Polarization bụ nchọta na ọdịdị ọdịdị (contour) nke mpaghara eletrik. Dị ka ihe atụ, tụlee akara n'ọdụ ụgbọ elu na-efegharị ọkụ eletrik (1). Anyị ga-ahụ ọnọdụ ebe ọkụ eletrik dị (X, Y, Z) = (0,0,0) dịka ọrụ nke oge. A na-edobe oke mpaghara a na eserese 2, n'ọtụtụ oge n'oge. Ogige ahụ na-ama jijiji na ugboro ole "F".
ọnụ ọgụgụ 2. Lelee oghere eletrik (X, Y, Z) = (0,0,0) n'oge dị iche iche.
A na-ahụ oghere eletrik na mmalite, na-emegharị azụ na azụ na njupụta. Ebe eletrik na-adị mgbe niile n'akụkụ axis egosipụtara. Ebe ọ bụ na a na-edobe ọkụ eletrik n'otu ahịrị, enwere ike ịsị na ọ bụ akara aka. Na mgbakwunye, ọ bụrụ na axis X dị na ala, a na-akọwakwa mpaghara a dị ka nke kwụ ọtọ. Ọ bụrụ na mpaghara ahụ gbadoro ụkwụ n'akụkụ axis Y, enwere ike ịsị na ebili mmiri ahụ na-agbado n'ụzọ kwụ ọtọ.
Ebili mmiri ndị kwụ ọtọ n'ahịrị adịghị mkpa ka eduzi ya n'akụkụ kwụ ọtọ ma ọ bụ kwụ ọtọ. Dịka ọmụmaatụ, ebili mmiri eletrik nwere mmachi dina n'akụkụ ahịrị dị ka egosiri na foto nke 3 ga-adịkwa n'ahịrị.
oyiyi 3. Igwe ọkụ eletrik njupụta nke ebili mmiri nke linearly polarized nke trajectory bụ akụkụ.
Enwere ike ịkọwa mpaghara eletrik dị na eserese 3 site na nha nha (2). Ugbu a enwere akụkụ x na y nke mpaghara eletrik. Akụkụ abụọ a hà nhata na nha.
Otu ihe ị ga-amabanyere gbasara nha anya (2) bụ mpaghara xy na eletrọnịkị na ọkwa nke abụọ. Nke a pụtara na akụkụ abụọ a nwere otu njupụta mgbe niile.
okirikiri polarization
Ugbu a, were ya na a na-enye oghere eletrik nke ikuku ụgbọ elu site na nha nha (3):
N'okwu a, ihe X- na Y bụ ogo 90 nke oge. Ọ bụrụ na a na-ahụ ubi ahụ dị ka (X, Y, Z) = (0,0,0) ọzọ dị ka ọ dị na mbụ, oghere eletrik na ogologo oge ga-apụta dị ka egosiri n'okpuru na foto 4.
Ọgụgụ 4. Ike ọkụ eletrik (X, Y, Z) = (0,0,0) ngalaba EQ. (3).
Ebe eletrik dị na eserese 4 na-atụgharị na gburugburu. A kọwara ụdị ubi a dị ka ebili mmiri nwere okirikiri. Maka polarization okirikiri, a ga-emezurịrị ụkpụrụ ndị a:
- Ọkọlọtọ maka polarization okirikiri
- Ebe ọkụ eletrik ga-enwerịrị akụkụ abụọ nke orthogonal (perpendicular).
- Akụkụ orthogonal nke mpaghara eletrik ga-enwerịrị nha nha nha.
- Ihe mejupụtara quadrature ga-abụrịrị ogo 90 site na nkeji.
Ọ bụrụ na ị na-eme njem na ihuenyo Wave Figure 4, a na-ekwu na ntụgharị mpaghara na-aga n'ihu elekere na aka nri okirikiri polarized (RHCP). Ọ bụrụ na a na-atụgharị mpaghara ahụ n'akụkụ elekere, ubi ahụ ga-abụ polarization okirikiri aka ekpe (LHCP).
Elliptical polarization
Ọ bụrụ na mpaghara ọkụ eletrik nwere akụkụ abụọ kwụ ọtọ, ogo 90 na-apụ n'oge mana nha nha, ebe ahụ ga-abụ polarized nke ọma. N'ịtụle oghere eletrik nke ụgbọ elu na-efegharị na ntụzịaka +z, nke akara (4) kọwara:
Enyere ebe ebe a na-ahụ n'ọnụ nke vector mpaghara eletrik ga-eche na foto 5
Ọgụgụ 5. Igwe ọkụ eletrik na-efegharị elliptical ozugbo. (4).
Ogige dị na eserese 5, na-eme njem na ntụgharị ihu elekere, ga-abụ elliptical aka nri ma ọ bụrụ na ọ na-apụ na ihuenyo. Ọ bụrụ na vector dị n'okirikiri eletrik na-atụgharị n'akụkụ nke ọzọ, ubi ahụ ga-abụ aka ekpe elliptically polarized.
Ọzọkwa, elliptical polarization na-ezo aka na ya eccentricity. The ruru nke eccentricity na njupụta nke isi na obere axes. Ọmụmaatụ, ebili mmiri eccentricity si nhata (4) bụ 1/0.3= 3.33. A na-akọwakwa ebili mmiri Elliptically polarized site na ntụzịaka nke isi axis. Nhazi ebili mmiri (4) nwere axis nke mejuputara axis x. Rịba ama na axis bụ isi nwere ike ịdị n'akuku ụgbọ elu ọ bụla. Achọghị ka akụkụ ahụ dabara na axis X, Y ma ọ bụ Z. N'ikpeazụ, ọ dị mkpa iburu n'obi na ma okirikiri okirikiri na linear polarization bụ ihe pụrụ iche nke elliptical polarization. 1.0 eccentric elliptically polarized ebili mmiri bụ ebili mmiri nwere okirikiri. Ebili mmiri nwere oghere nwere oghere na-enweghị ngwụcha. Ebili mmiri n'ahịrị kwụ ọtọ.
Antenna polarization
Ugbu a anyị maara mpaghara ikuku elektrọnik nke ikuku polarized, a na-akọwapụta polarization nke antenna.
Antenna Polarization Nleba anya n'ọhịa dị anya, polarization nke ubi na-apụta. Ya mere, a na-edekarị antenna dị ka "anụnụ polarized nke kwụ n'ahịrị" ma ọ bụ "antịnụ nwere okirikiri nwere okirikiri".
Echiche a dị mfe dị mkpa maka nkwukọrịta antenna. Nke mbụ, antenna nwere polarized kwụ ọtọ agaghị ekwurịta okwu na antenna kwụ ọtọ kwụ ọtọ. N'ihi usoro nkwụghachi ụgwọ, antenna na-ebufe ma nata n'otu ụzọ ahụ. Ya mere, antennas kwụ ọtọ kwụ ọtọ na-ebufe ma nata ubi ndị kwụ ọtọ kwụ ọtọ. Ya mere, ọ bụrụ na ị nwaa ibuga antenna polarị kwụ ọtọ kwụ ọtọ, agaghị enwe nnabata.
N'okwu n'ozuzu, maka antennas abụọ kwụ ọtọ na-atụgharị n'akụkụ ibe ha site n'akụkụ (), a ga-akọwapụta mfu ike n'ihi nhụsianya polarization a site na ihe nhụsianya polarization (PLF):
Ya mere, ọ bụrụ na antennas abụọ nwere otu polarization, akụkụ dị n'etiti oghere eletrọn ha na-egbuke egbuke bụ efu ma ọ dịghị ike ọ bụla n'ihi ndakọrịta polarization. Ọ bụrụ na otu antenna kwụ ọtọ na nke ọzọ na-agbaji n'ihu, akụkụ ya dị ogo 90, ọ nweghị ike ga-ebufe ya.
IHE: Ịbugharị ekwentị n'isi gị n'akụkụ dị iche iche na-akọwa ihe kpatara enwere ike ịbawanye nnabata mgbe ụfọdụ. A na-enwekarị eriri ekwentị n'ahịrị n'ahịrị, yabụ ịtụgharị ekwentị nwere ike na-adakọkarị na polarization nke ekwentị, si otú a na-emeziwanye nnabata.
Okirikiri polarization bụ ihe a na-achọsi ike nke ọtụtụ antennas. Antenna abụọ a na-eme okirikiri na-adịghị ata ahụhụ site na mfu mgbaàmà n'ihi ndakọrịta polarization. Antenna ndị a na-eji na sistemu GPS bụ aka nri okirikiri.
Ugbu a were were na antenna nwere eriri nwere eriri na-anata ebili mmiri nwere okirikiri. N'otu aka ahụ, were ya na antenna nwere okirikiri nwere okirikiri na-anwa ịnata ebili mmiri kwụ ọtọ. Kedu ihe kpatara mfu polarization?
Cheta na polarization okirikiri bụ n'ezie ebili mmiri abụọ n'ahịrị kwụ ọtọ, ogo 90 na-apụ apụ. Ya mere, antenna linearly polarized (LP) ga-anata naanị akụkụ nke ebili mmiri okirikiri (CP). Ya mere, antenna LP ga-enwe mgbaghara na-adịghị mma nke 0.5 (-3dB). Nke a bụ eziokwu n'agbanyeghị akụkụ nke antenna LP na-atụgharị. ya mere:
A na-akpọ ihe mfu polarization mgbe ụfọdụ dị ka arụmọrụ polarization, ihe na-adabaghị eri eri, ma ọ bụ ihe nnabata antenna. Aha ndị a niile na-ezo aka n'otu echiche.
Oge nzipu: Dec-22-2023
