A High-Gain Wideband Microstrip Patch Antenna With Folded Ground Walls

This paper proposes an approach to improve the gain of a microstrip patch antenna on a suspended substrate without compromising its bandwidth. The ground plane of the antenna is folded upwards to form sidewalls parallel to the non-radiating edges. The distance from the patch edges and the height of the sidewalls are determined to maximize the radiation performance of the resultant antenna. This approach results in a peak gain better than 12 dBi and impedance bandwidth of around 45\%. Simulation studies indicate that sidewalls parallel to radiating edges degrade the antenna performance.