8-Element circularly polarized microstrip array antenna

In this paper, the development of an eight-element circularly polarized microstrip array at 5.8 GHz is presented. Theory and experiment demonstrate both axial ratio 3 dB bandwidth and the voltage standing wave ratio (VSWR) 2:1 bandwidth of 8.6%. Different half power beamwidth at horizontal plane (16deg) and vertical plane (36deg) is achieved, and the measured array peak gain is 14 dBi at center frequency. The sequential rotation method for the element arrangement and array arrangement is employed to meet these objectives. The use of coplanar corporate feeds for microstrip patch arrays leads to constructional simplicity.