Compact Circularly Polarized Patch Antenna With Wide Axial-Ratio Beamwidth

This letter presents a compact circularly polarized patch antenna with wide axial-ratio (AR) beamwidth. The simulation reveals that by etching two pairs of asymmetric slots on the patch and loading coupled strips, the phase differences between the radiated orthogonal fields become flatter and maintain approximately at 90° over a wide angular range; hence, a wide AR beamwidth is achieved. Experimental results agree well with the simulation results. Particularly, this antenna achieves a wide AR beamwidth of 188° in both the principal and diagonal planes.