Microstrip Square Patch Antenna with Arc Shaped Edges for Circular Polarization

Microstrip square patch antennas with arc shaped grooves on the four edges are proposed and investigated. By cutting asymmetrical grooves on the square microstrip antenna, the single-feed microstrip antennas are realized for circularly polarized radiation. In this paper, several designs with different groove dimensions are listed, and all give good performance, providing a large flexibility in design and fabrication. Experimental results show that the proposed design has good circularly polarized radiation and an antenna-size reduction of about 35% compared to the conventional square patch antenna at a given operating frequency. Detailed results are presented and analyzed.