Application of broadband microstrip patch antenna as a perfect substitute for monopole antenna

A novel broadband omni-directional circular patch antenna is proposed to substitute for a broadband monopole antenna for its proverbial advantages. Considering the inherent narrow bandwidth of conventional microstrip patch antennas, electromagnetic coupling feed technology, shorting pins and matching network designed by means of genetic algorithm (GA) optimizers are used simultaneously to broaden the bandwidth of this circular patch antenna. This presented microstrip circular patch antenna can reach a bandwidth of 65% for voltage standing-wave ratio (VSWR) less than 2.3, and its least horizontal gain is greater than 0.2 dB which is almost the same as that of a monopole antenna working in this frequency band. Its horizontal pattern is as omni-directional as that of a monopole antenna, which enable it to replace a broadband monopole antenna commendably. The experimental results and simulation results agree with each other well.