Circularly Polarized Reconfigurable Omnidirectional Dielectric Resonator Antenna

A circularly polarized reconfigurable omnidirectional dielectric resonator antenna is proposed in this paper. The electric dipole mode of the dielectric resonator and the magnetic dipole mode of the arcs are combined to generate circularly polarized omnidirectional patterns. Six PIN diodes are organized into two groups to control the three arcs, enabling flexible RHCP/LHCP reconfiguration. The proposed antenna achieves circularly polarized radiation with an axial ratio below 2dB, covering the entire horizontal plane. It exhibits 5% (2.38-2.5GHz) -10dB impedance and 3dB axial ratio overlapping bandwidth. The main radiator of the dielectric resonator allows for a compact size $(0.44\lambda_{0}\times 0.44\lambda_{0}\times 0.14\lambda_{0})$ and high radiation efficiency over -1.2dB. Therefore, it is well-suited for WLAN systems to offer diverse polarizations and extensive coverage.