Wideband Polarization Reconfigurable Dielectric Resonator Antenna

A wideband polarization reconfigurable dielectric resonator antenna excited by quasi-lumped quadrature coupler (QLQC) is proposed. By adjusting the value of varactor diode on the QLQC feed network, both the wideband LP and CP dielectric resonator antennas (DRA) modes can be achieved. By selecting a different feed port, left-and right-handed CP conversion can be realized. It is found that the 10 dB impedance bandwidth of the LP and CP modes are 10.1% and 44.9%, respectively. For the CP mode, a very wide 3 dB axial ratio bandwidth of 37.7% can be obtained which is much larger than that of the microstrip patch counterpart (3.8%). It is worth mentioning that the wideband CP DRA has a stable broadside radiation pattern across the whole operating band where the boresight gain is larger than 3 dBi.