Paramita inobatsira pakuverenga simba rekugamuchira reantenna ndiyonzvimbo inoshandakanakuvhurika kunoshandaFungidzira kuti mafungu emudenga ane polarization yakafanana neanogamuchira antenna anoitika pa antenna. Fungidzira zvakare kuti mafungu ari kufamba akananga ku antenna nenzira yemwaranzi yepamusoro ye antenna (nzira iyo simba guru ringagamuchirwa nayo).

Ipapokuvhurika kunoshandaparameter inotsanangura kuti simba rakawanda sei rinotorwa kubva mumhepo yakapihwa.pkuve simba remafungu endege (muW/m^2). KanaP_tinomiririra simba (muWatts) pama terminals e antenna anowanikwa kune anogamuchira antenna, ipapo:

Saka, nzvimbo inoshanda inongoratidza kuti simba rakawanda sei rinotorwa kubva kumafungu endege uye rinounzwa neantenna. Nzvimbo iyi inotarisa mukurasikirwa kuri mukati meantenna (kurasikirwa kwe ohmic, kurasikirwa kwe dielectric, nezvimwewo).

Hukama hwakazara hwekuti aperture inoshanda sei maererano ne peak antenna gain (G) yechero antenna hunopiwa ne:

Aperture inoshanda kana nzvimbo inoshanda inogona kuyerwa pamaantenna chaiwo nekuenzanisa neantenna inozivikanwa ine aperture inoshanda, kana nekuverenga uchishandisa gain yakayerwa uye equation iri pamusoro.

Kuvhura zvakanaka kuchava pfungwa inobatsira pakuverenga simba rinogamuchirwa kubva kumafungu emuchadenga. Kuti uone izvi zvichiitwa, enda kuchikamu chinotevera cheFriis transmission formula.

Iyo Friis Transmission Equation

Papeji rino, tinosuma imwe ye equation dzakakosha mudzidziso ye antenna, iyoFriis Transmission Equation. Friis Transmission Equation inoshandiswa kuverenga simba rinogamuchirwa kubva kune imwe antenna (nekuwedzeraG1), kana ichitumirwa kubva kune imwe antenna (nekuwedzeraG2), yakaparadzaniswa nedaroR, uye kushanda kakawandafkana kuti wavelength lambda. Peji rino rakakodzera kuverengwa kanoverengeka uye rinofanira kunzwisiswa zvizere.

Kutorwa kweFriis Transmission Formula

Kutanga kutora Friis Equation, funga nezvemaantenna maviri ari munzvimbo yakasununguka (hapana zvipingamupinyi zviri pedyo) akaparadzaniswa nedaro.R:

Fungidzira kuti （）Mawatts esimba rese anoendeswa kune antenna inotumira. Parizvino, fungidzira kuti antenna inotumira haina divi rayo, haina kurasikirwa, uye kuti antenna inogamuchira iri kure kwe antenna inotumira. Ipapo simba remagetsi.p(muWatts pa square meter) yechiitiko chemafungu endege pa antenna inogamuchira daroRkubva ku antenna yekutumira inopiwa na:

Mufananidzo 1. MaAntena ekutumira (Tx) nekugamuchira (Rx) akaparadzaniswa neR.

Kana antenna inotumira iine antenna inowedzera zvakananga kune antenna inogamuchira yakapihwa na（）, saka equation yesimba rehuwandu iri pamusoro inova:

Izwi rekuti gain term rinoratidza divi uye kurasikirwa kweantenna chaiyo. Ngatitii zvino kuti antenna inogamuchira ine mukana unoshanda unobva()Zvadaro simba rinogamuchirwa neantenna iyi ( ) rinopihwa na:

Sezvo aperture inoshanda ye antenna chero ipi zvayo inogonawo kuratidzwa se:

Simba rakagamuchirwa rinogona kunyorwa seizvi:

Equation1

Izvi zvinozivikanwa seFriis Transmission Formula. Zvinobatanidza kurasikirwa kwenzira yemahara, kufambirana kweantenna uye wavelength nemasimba anogamuchirwa uye anotumirwa. Iyi ndeimwe ye equation dzakakosha mudzidziso yeantenna, uye inofanira kurangarirwa (pamwe chete nekubva pamusoro apa).

Imwe nzira inobatsira yeFriis Transmission Equation inopiwa muEquation [2]. Sezvo wavelength nefrequency f zvakabatana nekumhanya kwechiedza c (ona sumo kupeji refrequency), tine Friis Transmission Formula maererano nefrequency:

Equation2

Equation [2] inoratidza kuti simba rakawanda rinorasika pamafrequencies akakwira. Uyu ndiwo mhedzisiro huru yeFriis Transmission Equation. Izvi zvinoreva kuti kune maantenna ane gains yakatarwa, kuchinjirwa kwesimba kuchave kwakakwira pamafrequencies akaderera. Musiyano uripo pakati pesimba rinogamuchirwa nesimba rinotumirwa unozivikanwa sekurasikirwa kwenzira. Zvakataurwa neimwe nzira, Friis Transmission Equation inoti kurasikirwa kwenzira kwakakwira pamafrequencies akakwira. Kukosha kwemhedzisiro iyi kubva kuFriis Transmission Formula hakugone kuwedzeredzwa. Ndokusaka nharembozha dzichiwanzo shanda pasi pe2 GHz. Panogona kunge paine mafrequencies akawanda aripo pamafrequencies akakwira, asi kurasikirwa kwenzira kwakabatana hakuzogonese kugamuchira mhando. Semhedzisiro yeFriss Transmission Equation, ngatitii wakabvunzwa nezvemaantenna e60 GHz. Uchiona kuti frequency iyi yakakwira kwazvo, ungati kurasikirwa kwenzira kuchave kwakakwira zvakanyanya pakutaurirana kure - uye wakarurama chose. Pafrequencies yakakwira kwazvo (60 GHz dzimwe nguva inonzi mm (millimeter wave) region), kurasikirwa kwenzira kwakakwira kwazvo, saka kutaurirana kwepoint-to-point chete ndiko kunogoneka. Izvi zvinoitika kana mugamuchiri netransmitter vari mukamuri rimwe chete, uye vakatarisana. Seimwe nzira yeFriis Transmission Formula, munofunga here kuti vanoshanda nefoni vanofara nebhendi idzva reLTE (4G), iro rinoshanda pa700MHz? Mhinduro ndeiyi: iyi ifrequency yakaderera pane maantenna anowanzo shanda pairi, asi kubva kuEquation [2], tinoona kuti kurasikirwa nenzira kuchave kwakadererawo. Nokudaro, vanogona "kuvhara pasi zvakanyanya" nefrequency spectrum iyi, uye mukuru weVerizon Wireless munguva pfupi yapfuura akadana iyi "high quality spectrum", nekuda kwechikonzero ichi. Rutivi Runoti: Kune rumwe rutivi, vagadziri vefoni vanofanirwa kuisa antenna ine wavelength yakakura mumudziyo mudiki (frequency yakaderera = wavelength yakakura), saka basa remugadziri weantenna rakava rakaoma zvishoma!

Chekupedzisira, kana maantenna asina kuenzana ne polarization, simba rakagamuchirwa riri pamusoro rinogona kuwanda ne Polarization Loss Factor (PLF) kuti rionekwe zvakanaka kuti kusawirirana uku hakuna kuenzana. Equation [2] iri pamusoro inogona kuchinjwa kuti igadzire generalized Friis Transmission Formula, iyo inosanganisira kusawirirana kwe polarization: