Wideband Circularly-polarized Dielectric Resonator Antenna Array Based on Simplified Sequential-rotated Feeding Network

Abstract

A wideband circularly-polarized $2\times 2$ dielectric resonator antenna (DRA) array based on simplified sequential-rotated (SR) feeding network is presented. The modified cross-slot is utilized to excite two pairs of orthogonal modes in DRA with equal electric field amplitude and 90° phase difference in the working band. By combining these modes, −10 dB impedance bandwidth of 29.6% and 3-dB axial-ratio (AR) bandwidth of 19.4% can be obtained. Then, the $2\times 2$ DRA array based on simplified sequential-rotated feeding network is developed. Impedance bandwidth of 35.1% and AR bandwidth of 29.5% can be achieved for the proposed DRA array, which means 18.6% and 52.1% improvement when compared with the single DRA-element, respectively. In addition, the array also has stable radiation patterns in the CP operating band with peak gain of 12.3 dBic which is 6.4 dB higher than the DRA-element.