I-bandwidth yenye iparameter ye-antenna esisiseko. I-bandwidth ichaza uluhlu lweefrikhwensi ezinokuthi i-antenna ikwazi ukuzisasaza okanye ifumane amandla ngokuchanekileyo. Ngokwesiqhelo, i-bandwidth efunekayo yenye yeeparameter ezisetyenziselwa ukukhetha uhlobo lwe-antenna. Umzekelo, kukho iintlobo ezininzi ze-antenna ezine-bandwidth encinci kakhulu. Ezi antenna azinakusetyenziswa kwizicelo ze-broadband.
I-bandwidth idla ngokucatshulwa ngokwemilinganiselo ye-voltage standing wave ratio (VSWR). Umzekelo, i-antenna inokuchazwa njengene-VSWR <1.5 ngaphezulu kwe-100-400 MHz. Ingxelo ithi i-reflection coefficient ingaphantsi kwe-0.2 kuluhlu lwe-frequency olucatshulweyo. Ke ngoko, kumandla anikezelwa kwi-antenna, yi-4% kuphela yamandla abonakaliswayo abuyela kwi-transmitter. Ukongeza, ilahleko yokubuyisela i-S11 =20* LOG10 (0.2) = 13.98 decibels.
Nceda uqaphele ukuba oku kungasentla akuthethi ukuba i-96% yamandla ithunyelwa kwi-antenna ngohlobo lwemitha ye-electromagnetic esasazekileyo. Ukulahleka kwamandla kufuneka kuqwalaselwe.
Ukongeza, ipateni yemitha iya kwahluka ngokwexesha. Ngokubanzi, imilo yepateni yemitha ayitshintshi ngokupheleleyo ixesha.
Kusenokubakho neminye imigangatho esetyenziselwa ukuchaza i-bandwidth. Oku kungaba yi-polarization ngaphakathi koluhlu oluthile. Umzekelo, i-antenna ejikelezileyo enoburhabaxa inokuchazwa njengenomlinganiselo we-axial we-<3 dB ukusuka kwi-1.4-1.6 GHz (ngaphantsi kwe-3 dB). Olu luhlu lokuseta i-bandwidth yoburhabaxa lumalunga nee-antenna ezijikelezileyo ezinoburhabaxa.
I-bandwidth idla ngokuchazwa kwi-Fractional Bandwidth yayo (FBW). I-FBW ngumlinganiselo woluhlu lweefrikhwensi olwahlulwe yi-center frequency (i-frequency ephezulu ngaphandle kwe-frequency esezantsi). I-"Q" ye-antenna ikwanxulumene ne-bandwidth (i-Q ephezulu ithetha i-bandwidth esezantsi kunye ne-vice versa).
Ukunika imizekelo ethile ye-bandwidth, nantsi itheyibhile ye-bandwidths yeentlobo ze-antenna eziqhelekileyo. Oku kuya kuphendula imibuzo ethi, "Yintoni i-bandwidth ye-antenna ye-dipole?" kunye "Yeyiphi i-antenna ene-bandwidth ephezulu - i-patch okanye i-antenna ye-helix?". Ukuthelekisa, sinee-antenna ezine-frequency ephakathi ye-1 GHz (gigahertz) nganye.
Ububanzi bee-antenna ezininzi eziqhelekileyo.
Njengoko ubona kwitheyibhile, ububanzi be-antenna bunokwahluka kakhulu. Ii-antenna ze-patch (microstrip) zibubanzi be-bandwidth obuphantsi kakhulu, ngelixa ii-antenna ze-helical zine-bandwidth enkulu kakhulu.
Ixesha lokuthumela: Novemba-24-2023
