Ukufiphala kwetshaneli engenazingcingokukutshintsha kwe-amplitude yesignali efunyenweyo, isigaba okanye amandla abangelwa lutshintsho kwindlela yokusasazeka. Inganciphisa umda wekhonkco, itshintshe imiqondiso ye-wideband kwaye yenze kube nzima ukuphinda imilinganiselo ye-RF. Ukuqonda uhlobo lokufiphala olukhoyo kwinkqubo kunceda iinjineli zikhethe ii-antenna ezifanelekileyo, iindlela zovavanyo kunye neendlela zokunciphisa.
Esi sikhokelo sichaza ukufiphala okukhulu nokuncinci, iitshaneli ezithe tyaba nezikhetha amaza, ukufiphala okucothayo nokukhawulezayo, kunye neemodeli zetshaneli zezibalo eziqhelekileyo. Sikwabonisa indlela ipateni ye-antenna, i-polarisation kunye ne-test geometry ezichaphazela ngayo ukulinganiswa kokufiphala okusebenzayo.
Yintoni Ukunyamalala Kwetshaneli Engenazingcingo?
Isignali yerediyo ayifikeleli kumntu ofumana umyalezo ngendlela enye efanelekileyo. Izakhiwo, umhlaba, izithuthi, izixhobo kunye nezinye izinto zinokuvala, zibonakalise, zisasaze okanye zisasaze amaza e-electromagnetic. Iikopi ezininzi zesignali efanayo zinokufika ngokulibaziseka okwahlukeneyo, ubukhulu, izigaba kunye nee-engile zokufika. Ukudibana kwazo kunokuba nokwakha kwindawo enye okanye i-frequency kwaye kutshabalalise kwenye.
Ukufiphala kwahlukile ekulahlekeni kwendlela ekhululekileyo eqinisekileyo. Ukufiphala kwendlela kuchaza ukuncitshiswa kwamandla ngokubanzi njengokunyuka komgama kunye nokwanda kwamaza, ngelixa ukufiphala kuchaza umahluko owongezelelweyo malunga naloo myinge. Iinjineli zihlala zihlela ukufiphala kwii-axes ezimbini ezizimeleyo: isikali sendawo kunye nokukhetha itshaneli.
Umfanekiso 1.Utshintsho olucothayo nolukhawulezayo kwinqanaba lesignali efunyenweyo lubonisa ixesha elahlukileyo lokunyamalala okanye izikali zomgama.
Indlela i-Wireless Fading ehlelwa ngayo
Ukunyamalala okukhuluichaza utshintsho oluhamba kancinci kancinci kumgama omde, ikakhulu ngenxa yokutshintsha kwendlela kunye nokulahleka kwayo kunye nomthunzi.Ukunyamalala okuncinciichaza utshintsho olukhawulezileyo kwimigama emifutshane okanye amaxesha amafutshane ngenxa yeendlela ezininzi kunye nokuhamba.
Ukufiphala okuncinci kunokwahlulwa ngokusasazeka kokulibaziseka njengokuthe tyaba okanye okukhetha imvamisa, kwaye ngokusasazeka kweDoppler njengokucotha okanye okukhawulezayo. Ezi ziindlela ezahlukeneyo zokwahlulahlula: itshaneli inokuba tyaba kwaye ikhawuleze, ithambe kwaye icothe, ikhetha imvamisa kwaye ikhawuleze, okanye ikhetha imvamisa kwaye icothe.
Ukunyamalala Okukhulu: Ukulahleka Kwendlela Nokufiphala
Indlela yokulahleka kwendlela
Ukulahleka kwendlela kukunciphisa okuqhelekileyo kwamandla afunyenweyo ngomgama wokusasazeka. Kwindawo ekhululekileyo engaphazanyiswanga, ukulahleka kunxulumene nobude be-wavelength kunye nomgama. Iindawo zokwenyani zongeza umhlaba, ukuxinana, iziphumo zomoya kunye nokuxhomekeka kokuphakama kwe-antenna, ngoko ke uhlahlo-lwabiwo mali olusebenzayo ludla ngokusebenzisa imodeli yokusasazeka efanelekileyo kwimeko yokusasazeka.
Umthunzi uyaphela
Umthunzi wenzeka xa izinto ezinkulu zithintela indlela yokusasazeka ngokuthe ngqo okanye ngokupheleleyo. Izakhiwo, iinduli, oomatshini kunye nemizimba yezithuthi zinokuvelisa utshintsho olucothayo kwinqanaba elifunyenweyo njengoko umthumeli, umamkeli okanye indawo engqongileyo itshintsha. Ukuphela komthunzi kudla ngokubonakaliswa ngokwezibalo malunga nokulahleka kwendlela ephakathi kwendawo.
Ukuncipha Komlinganiselo Omncinci: Iindlela Ezininzi Nentshukumo
Ukufiphala okuthe tyaba xa kuthelekiswa nokufiphala okukhethwa rhoqo
Itshaneli imalungaukufiphala okuthe tyabaxa i-bandwidth yayo yokuhambelana ibanzi kune-bandwidth yesignali esetyenzisiweyo. Itshaneli emva koko itshintsha ubukhulu besignali kunye nesigaba ngaphandle kokutshintsha ngamandla i-spectrum yayo.
Itshaneli ibaukukhetha rhoqoxa i-bandwidth yesignali inkulu xa ithelekiswa ne-bandwidth yokuhambelana. Iinxalenye ezahlukeneyo ze-spectral zifumana inzuzo kunye nesigaba esahlukileyo. Isizathu esisisiseko kukusasazeka kokulibaziseka kwe-multipath okusombululekayo, okunokubangela ukuphazamiseka kwe-intersymbol kwiikhonkco zedijithali.
Ukufiphala kancinci xa kuthelekiswa nokufiphala ngokukhawuleza
Ukunyamalala kancinci kancincikuthetha ukuba itshaneli ayitshintshi kangako ngexesha lesithuba esifanelekileyo sokubonisa.Ukunyamalala ngokukhawulezakuthetha ukuba itshaneli itshintsha kakhulu kuloo sithuba. Intshukumo enxulumeneyo phakathi kwe-transmitter, i-receiver kunye ne-scatterers ezingqongileyo ivelisa utshintsho lwe-Doppler kwaye inciphisa ixesha lokuvumelana kwetshaneli.
| Ulwahlulo | Uthelekiso oluphambili | Isiphumo esiqhelekileyo |
|---|---|---|
| Ukufiphala okuthe tyaba | I-bandwidth yesignali incinci kune-bandwidth yokuhambelana | Ubungakanani obubanzi kunye nokwahluka kwesigaba kuyo yonke isignali |
| Ukukhetha rhoqo | I-bandwidth yesignali inkulu kune-bandwidth yokuhambelana | Ukuphazamiseka kwe-Spectral kunye nokuphazamiseka okunokwenzeka phakathi kweempawu |
| Ukunyamalala kancinci kancinci | Ixesha lokuvumelana lide xa lithelekiswa nexesha lokubonisana | Ukwahluka kancinci kancinci kwinqanaba lonxibelelwano |
| Ukunyamalala ngokukhawuleza | Ixesha lokuvumelana lifutshane xa lithelekiswa nexesha lokubonisana | Utshintsho olukhawulezayo kunye nokuphazamiseka okunxulumene neDoppler |
Iimodeli eziqhelekileyo zokuFipha kwezibalo
- Ukunyamalala kukaRayleigh:isetyenziswa rhoqo xa kungekho nto iphambili ebonakala ngayo kwaye isignali efunyenweyo yenziwe zizinto ezininzi ezisasazekileyo.
- Ukunyamalala kukaRician:ibandakanya icandelo elilawulayo kunye neenxalenye ze-multipath ezisasazekileyo. I-Rician K-factor ichaza umlinganiselo wamandla phakathi kweenxalenye ezilawulayo kunye nezisasazekileyo.
- Ukunyamalala kweNakagami:usasazo oluguquguqukayo olunokumela uluhlu lobunzima obuphelayo ngeparameter yayo yesimo.
- Ukufiphala kweWeibull:olunye usasazo lwezibalo oluguquguqukayo olusetyenziselwa iindawo ezikhethiweyo zokusasazeka ezilinganisiweyo.
Ukukhethwa kwemodeli kufuneka kusekelwe kwindawo yokwenyani, imvamisa, ukuhambahamba, uqwalaselo lwe-antenna kunye nedatha yokulinganisa. Iindlela zokusebenza zeMATLAB zanamhlanje zisebenzisa izinto ezinjei-comm.RayleighChannelkwayecomm.RicianChannelendaweni yemisebenzi ephelelwe lixesha ekhankanyiweyo kwinguqulelo yangaphambili yale nqaku.
Umfanekiso 3.Ukusasazwa kweemvulophu zezibalo kubonelela ngeemodeli ezincinci zokuziphatha okulinganiselweyo kokuphela.
Indlela Ukufiphala Okuchaphazela Ngayo Ukusebenza Kwenkqubo YeRF
Ukufiphala kunokunciphisa amandla afunyenweyo, umlinganiselo wesignali-kwingxolo uphantsi, ukonyusa izinga leempazamo kunye nokuphazamisa ikhonkco lerediyo. Ukufiphala okukhethwa rhoqo kunokuphazamisa ii-waveforms ze-wideband, ngelixa ukutshintsha ngokukhawuleza kweDoppler kunokwenza uqikelelo lwesiteshi lube nzima ngakumbi.
Iindlela eziqhelekileyo zokunciphisa uxinzelelo ziquka:
- umda wekhonkco owaneleyo kunye nolawulo lokufumana ngokuzenzekelayo;
- ixesha, ukuphindaphinda, ukwahlukahlukana kwendawo okanye ukwahlukahlukana;
- ukulingana kunye noyilo lwe-waveform yeenkampani ezininzi;
- ikhowudi yetshaneli, ukudibanisa kunye nokuguquguquka okuguquguqukayo;
- Ukucubungula i-MIMO kunye nokulawula imiqadi;
- Ukubekwa ngononophelo kwe-antenna, ukukhethwa kweepateni kunye nolawulo lwe-polarization.
Akukho ndlela inye esusa zonke iindlela eziphelayo. Indlela echanekileyo ixhomekeke kwizibalo zesiteshi, i-bandwidth ehlala abantu, ukuhambahamba, iimfuno zokugubungela kunye namathuba okwamkelekileyo okucima.
Umfanekiso 4.Idatha elinganisiweyo kufuneka imisele ukuba usasazo lwezibalo lufanelekile na kwitshaneli ethile.
Ukukhethwa kwee-Antena zoVavanyo lweChannel Sounding kunye neFiding
I-antenna ayidali itshaneli yokusasazeka ngokwayo, kodwa ichaphazela kakhulu iindlela kunye ne-polarizations ezidluliselwayo okanye ezifunyanwayo. I-Gain, i-beadwidth, i-radiation pattern, i-polarization purity, i-phase stability kunye ne-mounting geometry zonke ezi zinokuchaphazela indlela yokuziphatha kwetshaneli elinganisiweyo.
Ukuze ufumane imilinganiselo ephindaphindwayo yetshaneli okanye yokufiphala, bhala:
- uluhlu olupheleleyo lweefrikhwensi kunye ne-bandwidth yokulinganisa ngokukhawuleza;
- ukuzuza kwe-antenna kunye nobubanzi be-beammit ngokuhamba rhoqo;
- iimfuno ze-polarization ezithe tye, ezithe tye okanye ezijikelezayo;
- ukuphakama kwe-antenna, ukujongwa kwayo, isithuba kunye nezakhiwo ezingqongileyo;
- Isixhumi se-RF, ukulahleka kwentambo kunye ne-calibration reference plane;
- intshukumo yomthumeli, umamkeli kunye nomsasazi;
- ukusasazeka kokulibaziseka, ukusasazeka kweDoppler kunye noluhlu oluguqukayo olufunekayo.
Iinketho ze-antenna ze-RF MISO
I-RF MISO iyila kwaye ibonelela ngee-antenna ze-RF kunye nee-microwave zomsebenzi webhubhoratri, intsimi kunye nokudibanisa inkqubo. Ngokuxhomekeke kugubungela okufunekayo kunye nejometri yokulinganisa, iinjineli zinokuqwalaselaii-eriyali zeempondo ze-broadbandukulinganisa i-wideband yecala,ii-antenna ze-log-periodicukuze kugqunywe amaza amaninzi, okanyeii-antenna ezibhekisa kwicala ngalinyekwiinkalo ezikhethiweyo zokugubungela kunye nezifundo zokusasaza.
Hlaziya i-datasheet yemodeli yangoku ukuze ufumane uluhlu lwefrikhwensi, i-gain, i-polarization, i-VSWR, i-connector kunye nobukhulu boomatshini. Ukuze ukhethe uhlobo oluthile lwesicelo, yabelana ngebhendi yovavanyo, i-bandwidth, ipateni efunekayo, i-polarization, imida yokufakela kunye nendawo yokulinganisa neqela le-RF MISO.
Xoxa ngeMfuneko yakho yoKulinganisa i-RF
I-RF MISO inokunceda ekuchongeni iindlela ze-antenna zokusasaza iziteshi, izifundo zokusasaza, uvavanyo lwenkqubo engenazingcingo kunye nokulinganiswa kwe-RF okunxulumene noko.
Iingxelo kunye nokufunda okungakumbi
Ixesha lokuthumela: Agasti-14-2023
