Siga mai fa'ida mai ƙididdige ikon karɓar eriya shineyanki mai tasirikom budewa.A ɗauka cewa igiyar jirgin sama mai polarization iri ɗaya kamar eriyar karɓa ta faru akan eriya.A ci gaba da ɗauka cewa igiyar ruwa tana tafiya zuwa eriya a cikin hanyar eriya ta mafi girman radiation (yankin da mafi yawan iko za a karɓa).
Sai kumam budewasiga yana kwatanta adadin ƙarfin da aka kama daga igiyar jirgin da aka ba da.Baripzama ƙarfin ƙarfin motsin jirgin sama (a cikin W/m^2).IdanP_tyana wakiltar iko (a cikin Watts) a tashoshin eriya da ke samuwa ga mai karɓar eriya, sannan:
Don haka, yanki mai tasiri kawai yana wakiltar adadin ƙarfin da aka kama daga igiyar jirgin da kuma isar da eriya.Wannan yanki yana haifar da asara na asali ga eriya (asarar ohmic, asarar dielectric, da sauransu).
Alaka gabaɗaya don ingantaccen buɗaɗɗen buɗaɗɗiya dangane da ƙimar eriya kololuwa (G) na kowane eriya ana bayarwa ta:
Za'a iya auna madaidaicin buɗaɗɗen buɗaɗɗiyar ko yanki mai tasiri akan eriya na ainihi ta kwatanta da sanannen eriya tare da ingantaccen buɗaɗɗen buɗewa, ko ta hanyar ƙididdigewa ta amfani da ƙimar da aka auna da ma'aunin da ke sama.
Ingantacciyar buɗaɗɗen buɗaɗɗiyar za ta zama ra'ayi mai amfani don ƙididdige ikon da aka karɓa daga igiyar jirgin sama.Don ganin wannan a aikace, je zuwa sashe na gaba akan tsarin watsa Friis.
Equation na watsa Friis
A wannan shafin, mun gabatar da ɗaya daga cikin mahimman ma'auni a ka'idar eriya, daDaidaiton Watsawa Friis.Ana amfani da ma'aunin watsawa na Friis don ƙididdige ikon da aka karɓa daga eriya ɗaya (tare da ribaG1), lokacin da aka watsa daga wata eriya (tare da ribaG2), rabu da nisaR, da kuma aiki a mitafko wavelength lambda.Wannan shafin ya cancanci karanta sau biyu kuma ya kamata a fahimce shi sosai.
Samuwar Formula na watsa Friis
Don fara samo ma'aunin Friis, la'akari da eriya biyu a cikin sarari kyauta (babu wani shinge a kusa) wanda aka raba ta tazara.R:
A ɗauka cewa () Watts na jimlar ƙarfi ana isar da su zuwa eriyar watsawa.A halin yanzu, ɗauka cewa eriyar watsawa ta ko'ina ce, mara asara, kuma eriyar karɓa tana cikin filin nesa na eriyar watsawa.Sai karfin ikop(a cikin Watts a kowace murabba'in mita) na lamarin girgizar jirgin sama akan eriyar karɓa nesaRdaga eriyar watsawa ana bayarwa ta:
Hoto 1. Watsawa (Tx) da Karɓa (Rx) Eriya ta raba taR.
Idan eriya mai watsawa tana da ribar eriya a cikin hanyar eriyar karɓar da aka bayar () , to, ƙimar ƙarfin ƙarfin da ke sama ya zama:
Abubuwan da ake samu a cikin shugabanci da asarar eriya ta gaske.A ɗauka yanzu cewa eriyar karɓa tana da ingantaccen buɗaɗɗen buɗewa da aka bayar().Sannan wutar da wannan eriya ( ) ta samu tana bada:
Tunda ingantaccen buɗaɗɗen eriya kuma ana iya bayyana shi kamar:
Za a iya rubuta sakamakon da aka samu kamar haka:
Daidaito1
Wannan ana kiransa da Tsarin watsa Friis.Yana da alaƙa da asarar hanyar sarari kyauta, ribar eriya da tsayin igiyoyin da aka karɓa da watsawa.Wannan yana ɗaya daga cikin mahimman ma'auni a ka'idar eriya, kuma yakamata a tuna (da kuma abin da aka samo a sama).
An bayar da wani nau'i mai fa'ida na daidaitattun watsawar Friis a cikin Equation [2].Tun da tsayin raƙuman ruwa da mitar f suna da alaƙa da saurin haske c (duba intro zuwa shafi na mitar), muna da Tsarin watsa Friis dangane da mitar:
Daidaitawa2
Ƙididdigar [2] yana nuna cewa ƙarin iko yana ɓacewa a mafi girman mitoci.Wannan babban sakamako ne na daidaitattun watsawar Friis.Wannan yana nufin cewa don eriya tare da ƙayyadaddun riba, canja wurin makamashi zai kasance mafi girma a ƙananan mitoci.Bambanci tsakanin ikon da aka karɓa da ikon da aka watsa ana sani da asarar hanya.An ce ta wata hanya dabam, Friis Transmission Equation ya ce asarar hanyar ta fi girma ga mitoci masu girma.Muhimmancin wannan sakamakon daga Tsarin Watsawa na Friis ba zai yiwu ba.Wannan shine dalilin da ya sa gabaɗaya wayoyin hannu suna aiki a ƙasa da 2 GHz.Ana iya samun ƙarin mitar bakan da ake samu a mitoci mafi girma, amma asarar hanyar da ke da alaƙa ba za ta ba da damar liyafar inganci ba.A sakamakon ƙarin sakamakon Friss Transmission Equation, a ce an tambaye ku game da eriya 60 GHz.Lura cewa wannan mitar yana da girma sosai, zaku iya bayyana cewa asarar hanyar za ta yi yawa don sadarwa mai nisa - kuma kun yi daidai.A mitoci masu girma sosai (60 GHz wani lokaci ana kiranta da yanki mm (millimita wave), asarar hanyar tana da girma sosai, don haka sadarwa ta aya-zuwa kawai zai yiwu.Wannan yana faruwa ne lokacin da mai karɓa da na'urar watsawa suke cikin ɗaki ɗaya, kuma suna fuskantar juna.A matsayin ƙarin bayani na Tsarin Watsa Labarai na Friis, kuna tsammanin masu aikin wayar hannu suna farin ciki game da sabon rukunin LTE (4G), wanda ke aiki a 700MHz?Amsar ita ce e: wannan ƙananan mita ne fiye da eriya da ke aiki a al'ada, amma daga Equation [2], mun lura cewa asarar hanyar za ta kasance ƙasa da ƙasa.Don haka, za su iya "rufe ƙasa mai yawa" tare da wannan mitar bakan, kuma wata zartarwa ta Verizon Wireless kwanan nan ta kira wannan "high quality spectrum", daidai wannan dalili.Bayanin gefe: A gefe guda, masu yin wayar salula za su dace da eriya mai tsayi mai girma a cikin ƙaramin na'ura (ƙananan mitar = babban tsayin raƙuman ruwa), don haka aikin ƙirar eriya ya ɗan ƙara rikitarwa!
A ƙarshe, idan eriya ba ta dace da polarization ba, ƙarfin da aka karɓa na sama zai iya ninka ta hanyar Polarization Loss Factor (PLF) don yin lissafin daidai wannan rashin daidaituwa.Za'a iya canza lissafin [2] na sama don samar da tsarin jujjuyawar juzu'i na Friis, wanda ya haɗa da rashin daidaiton polarization:
Daidaito3
Lokacin aikawa: Janairu-08-2024
