Differential Dual-Band Dual-Polarized Dielectric Resonator Antenna

This communication presents a differential dual-band dual-polarized dielectric resonator antenna (DRA) with high isolation and low cross polarization using a cross-shaped DR. In the differential DRA, some of the higher order modes are eliminated and electromagnetic fields of each excited mode have no interaction with its corresponding orthogonal mode. Two groups of modes are utilized to realize dual-band characteristic and each group with two orthogonal modes is used to supply dual-polarized function. Differential feeding provides the DRA with suppression of unwanted modes, much higher isolation and lower cross-polarization in both frequency bands, compared with the traditional single-end feeding. The experimental prototypes of the proposed differential DRA and its single-ended counterpart are designed and implemented. The comparison between them is also made in reflection coefficient, isolation, and radiation properties. Both simulated and measured results show significantly improved performance of the proposed differential DRA.