Broadband probe-fed patch antenna with a U-shaped ground plane for cross-polarization reduction

A broadband probe-fed patch antenna with a novel three-dimensional (3D) U-shaped ground plane is proposed and experimentally studied. The proposed antenna has a thick air substrate, and by placing the two flanges of the U-shaped ground plane in parallel to and at a suitable distance from the radiating edges of the antenna's radiating patch, a wide impedance bandwidth (>25%) with much reduced cross-polarization radiation can be obtained, compared to the case with a conventional planar ground plane. In addition, enhanced antenna gain for the proposed antenna is also observed. Details of the proposed antenna and experimental results are presented and discussed.