Polarization Reconfigurable Compact and Highly Efficient Cube Antenna

This paper proposes a highly efficient and compact cube antenna that can reconfigure its polarization using artificial magnetic conductor (AMC) side walls. Fabry-Perot (FP) resonance condition was employed along with cavity resonance condition to maximize antenna gain. To calculate cavity modes affected by AMC reflection phases, conventional formulas were modified. Consequently, it became feasible to control polarization by forming TE101 mode for vertical polarization or TE011 mode for horizontal polarization. A conventional microstrip patch antenna was used as a feeding antenna, with a 45° rotated patch, and the AMC reflection phase was adjusted appropriately to radiate the desired polarization. The developed antenna measured 0.48 λ×0.48 λ×0.47 λ and exhibited a remarkable improvement in aperture efficiency, reaching 141 %, compared to the conventional FPC antenna.