Circularly Polarized (CP) Two-Dimensional Standing-Wave Microstrip Array Antenna with a Single Feed

A novel circularly polarized (CP) microstrip array antenna with a single feed (SF) working at 1.948 GHz is presented. The array design is based on a standing-wave concept. Only one array element is fed by a single coaxial probe to produce a standing wave within the antenna cavity of the array structure. The feed element is designed to produce CP radiation using Bethe holes on the microstrip patch. The resultant microstrip array is compact with a small axial ratio (AR) and excellent CP quality over the entire radiation angle. The design procedure is relatively straightforward.