Proposal of wideband reconfigurable circular-polarized single-port antenna

Reconfigurable circular-polarized antennas are expected to improve ground penetrating radars (GPRs) utilizing high-density arrayed and complexly switched antennas. This report presents a wideband reconfigurable circular-polarized single-feed antenna. It comprises a waveguide and a T-shaped probe. We switch its polarization type by changing the bias state of two PIN diodes on the T-probe. Simulation results show that the 3-dB axial ratio bandwidth of the proposed antenna is 29% at 7.5GHz center frequency. The results also show that the main-polarized beam width is 70 degree in the 3-dB axial ratio bandwidth.