Dual-polarized dielectric resonator array antenna with low cross-polarization

A dual-polarized (DP) dielectric resonator array antenna with low cross-polarization and high isolation is proposed for the synthetic aperture radar (SAR) applications. Owing to its high efficiency, the dielectric resonator antenna (DRA) is adopted as the higher frequency radiator operated in X-band. In order to obtain the dual polarization with a low cross-polarization, the horizontal polarization is excited in the center of the DR while the vertical polarization is fed by two slot feeds with 180° out of phase. The DP DRA element demonstrates a port isolation exceeding 51dB and a cross-polarization level of -35dB As a test model, the array of 1×4 elements is designed and analyzed. Simulation results show that the impedance bandwidth of return loss less than -10 dB is 16.6% from 8.85 GHz to 10.45 GHz. The cross-polarization levels of the test antenna array is -38 dB in both planes.