DESIGN OF A BROADBAND SWITCHED-BEAM ANTENNA ARRAY WITHREDUCED MUTUAL COUPLING EFFECTS FOR WIRELESSCOMMUNICATION

摘要

A broadband four-port switched-beam antenna withreduced mutual coupling effects is designed andimplemented. The proposed switched-beam antennasystem including a broadband Butler matrix as a feedingstructure and four bowtie-shaped microstrip antennas asdriver elements provide good radiation patterns only usingfour radiating elements. To reduce the side-lobe level ofantenna array, metallic strips between radiating elementscan be considered. Four bowtie-shaped with reflected-ground plane antennas in conjunction with the broadbandfour-port Butler matrix are applied to create radiationpattern in different directions and to obtain a front-to-backratio for 20dB. From the measured results, the side-lobelevel is approximately below -10dB.