Bandwidth ndi gawo lina lofunikira la antenna. Bandwidth imafotokoza kuchuluka kwa ma frequency omwe antenna imatha kutulutsa kapena kulandira mphamvu molondola. Kawirikawiri, bandwidth yofunikira ndi imodzi mwa magawo omwe amagwiritsidwa ntchito posankha mtundu wa antenna. Mwachitsanzo, pali mitundu yambiri ya antenna yokhala ndi bandwidth yaying'ono kwambiri. Ma antenna awa sangagwiritsidwe ntchito mu mapulogalamu a broadband.
Bandwidth nthawi zambiri imatchulidwa malinga ndi chiŵerengero cha mafunde oima (VSWR). Mwachitsanzo, antenna ingatanthauzidwe kuti ili ndi VSWR <1.5 pa 100-400 MHz. Chikalatacho chimanena kuti coefficient yowunikira ndi yochepera 0.2 kudutsa ma frequency omwe atchulidwa. Chifukwa chake, pa mphamvu yoperekedwa ku antenna, 4% yokha ya mphamvuyo imawonetsedwanso kubwerera ku transmitter. Kuphatikiza apo, kutayika kobwerera S11 = 20* LOG10 (0.2) = 13.98 decibels.
Dziwani kuti zomwe zili pamwambapa sizikutanthauza kuti 96% ya mphamvu imaperekedwa ku antenna mu mawonekedwe a ma radiation amagetsi ofalikira. Kutayika kwa mphamvu kuyenera kuganiziridwa.
Kuphatikiza apo, mawonekedwe a kuwala amasiyana malinga ndi kuchuluka kwa kuwala. Kawirikawiri, mawonekedwe a mawonekedwe a kuwala sasintha kwambiri kuchuluka kwa kuwala.
Pakhoza kukhalanso miyezo ina yogwiritsidwa ntchito pofotokoza bandwidth. Izi zitha kukhala polarizating mkati mwa range inayake. Mwachitsanzo, antenna yozungulira polarized ingatanthauzidwe kuti ili ndi axial ratio ya <3 dB kuchokera ku 1.4-1.6 GHz (yochepera 3 dB). Range iyi ya polarization bandwidth setting ndi pafupifupi ya antenna yozungulira polarized.
Bandwidth nthawi zambiri imatchulidwa mu Fractional Bandwidth yake (FBW). FBW ndi chiŵerengero cha ma frequency range chogawidwa ndi center frequency (highest frequency minus lowest frequency). "Q" ya antenna imakhudzananso ndi bandwidth (higher Q imatanthauza bandwidth yotsika ndi vice versa).
Kuti tipereke zitsanzo zenizeni za bandwidth, nayi tebulo la bandwidth ya mitundu yodziwika bwino ya antenna. Izi ziyankha mafunso, "Kodi bandwidth ya antenna ya dipole ndi chiyani?" ndi "Ndi antenna iti yomwe ili ndi bandwidth yayikulu - chigamba kapena antenna ya helix?". Poyerekeza, tili ndi antenna yokhala ndi pafupipafupi yapakati ya 1 GHz (gigahertz) iliyonse.
Ma bandwidth a ma antenna angapo ofala.
Monga mukuonera patebulo, bandwidth ya antenna imatha kusiyana kwambiri. Ma antenna a patch (microstrip) ndi bandwidth yotsika kwambiri, pomwe ma antenna a helical ali ndi bandwidth yayikulu kwambiri.
Nthawi yotumizira: Novembala-24-2023
