Wireless digital kutaurirana: Kushanda musimboti weIQ modulation

Wireless digital kutaurirana: Kushanda musimboti weIQ modulation
IQ modulation ndiyo nheyo yemhando dzakasiyana-siyana dzepamusoro-soro dzekugadzirisa nzira dzinoshandiswa zvakanyanya muLTE uye WiFi minda, yakadai seBPSK, QPSK, QAM16, QAM64, QAM256, etc. Kunzwisisa kushanda kwekushanda kweIQ modulation kunokosha kuti tinzwisise zviri nani nzira yekushanda kweOFDM muLTE neWiFi. Nekuti nzira dzemodulation dzinoshandiswa pane imwe neimwe subcarrier yeOFDM dzichiri dzakasiyana siyana QAM modulation matekiniki zvichibva paIQ modulation, uye zvakanyanya, kuita kweOFDM ndiko kukwirisa kweIQ modulation pane akawanda orthogonal subcarriers.
Mafungiro eI uye Q muIQ modulation anoenderana nepfupiso yemazwi maviri echiRungu: Muchikamu uye Quadrature, zvichiteerana. Kungotaura kubva pane zvazvinoreva, mazita eI neQ masaini haana zvaanoreva. Chii chinonzi in-phase? Chii chinonzi orthogonality? Ndechipi chiratidzo chinoshandiswa sereferensi yekuona mu-phaseuye quadrature? Mukuita kunoshanda, seti ye cosine uye sine mafungu eiyo frequency anowanzo shandiswa seI uye Q masaini. Naizvozvo, iyo cosine chiratidzo chinoshandiswa seI chiratidzo chaicho chiratidzo chereferenzi, icho chiri chokwadi cheIn Phase chiratidzo. Chiratidzo checosine icho chiri 90 madhigirii kunze kwechikamu neI chiratidzo chinowanzova chiratidzo cheQuadrature. Saka nzwisiso yakapusa yeIQ modulation masiginecha ndeye kufunga iyo I chiratidzo senge cosine inotakura chiratidzo, uye iyo Q chiratidzo sesine inotakura chiratidzo ine frequency musiyano we90 madhigirii kubva kuI chiratidzo.

Iyo inodaidzwa kuti IQ modulation ndeye kushandisa seti yezviratidzo zveI, zvinoti cosine masaini, uye masaini eQ, anoti sine masaini (ane mutsauko wechikamu che90 madhigirii uye orthogonal kune mumwe nemumwe) weiyo yakafanana frequency sevatakuri, panguva imwe chete modulate maviri baseband masaini kune maviri anotakura, uyezve kupfuudza iwo maviri edunhu nekuashandura masaini maRF. Mushure mekugamuchira redhiyo frequency chiratidzo, magumo ekugamuchira anoitaIQ demodulation. Munguva yeIQ demodulation, nekuti iwo maviri anotakura ari orthogonal kune mumwe nemumwe, iwo maviri baseband masaini anogona kupatsanurwa kubva kune yakasanganiswa siginecha zvichienderana neI uye Q masaini anotakura anoshandiswa mune yakapfuura modulation process uye kuderedzwa zvakasiyana. Kune ese masaini eI neQ akagadziridzwa neIQ, kuwedzera hukama hwedivi rimwe chete kwete kungowedzera amplitude yechiratidzo chakagadziridzwa, asi zvakare kunokonzeresa kuti chikamu cheiyo modulated chiratidzo chiende kudivi nekuwedzera amplitude. Saka zvakanyanya, IQ modulation ndeye amplitude modulation yakaitwa paI siginecha uye Q chiratidzo, asi modulation mhedzisiro haingokanganisa amplitude yeiyo modulated chiratidzo, asiwo shanduko yechikamu. Iyi ndiyo yekutanga kushanda musimboti weIQ modulation uye demodulation.