26 July 2021 in IEEE Transactions on Antennas and Propagation
In this paper, two wideband dual-polarized Dielectric Resonator Antennas (DRA) for X band radar applications are presented. The design procedure is started with designing a linear polarized DRA fed by a microstrip line. The feedline is optimized to excite the HEM11δ mode of DRA which corresponds to magnetic monopole like radiation. Then, a novel quadrature hybrid is designed in the feeding structure to provide both left (LHCP) and right-handed (RHCP) circular polarization. Finally, two antenna prototypes are fabricated and tested: a dual (right hand and left hand) circular polarization DRA with omni-directional pattern, and an enhanced gain version of dual-polarized CP DRA with a directive pattern. The measurement results of antennas confirm wideband impedance bandwidth (34% and 38.8%) as well as wideband Axial Ratio (AR) one (23% and 30%) in element and array structures, respectively. The antennas also provide both RHCP and LHCP radiation. The first antenna contains monopole-like radiation which is aimed at wireless systems with omnidirectional pattern requirements. The second, a 2*1 antenna array, which presents around 9 dB across the entire band. The presented antennas are good candidates for radar applications such as weather monitoring, air traffic control, and vehicle speed detection.