A Wideband Microstrip-Fed Dielectric Resonator Antenna Array With Defected Ground Structure

In this paper, a wideband microstrip-fed dielectric resonator antenna (DRA) array with defected ground structure (DGS) is presented. A 2×2 DRA array fed by parallel microstrip lines is proposed and its impedance bandwidth is further broadened by introducing four dumbbell shaped DGS units on the ground plane. It is found that the array with DGS has a wider impedance bandwidth of 30.4%, which is about 11.5% larger than that of the case without the DGS. The working principle of the DGS in broadening the bandwidth of the array is explored. In addition, the influences of the DGS on the back lobe and cross polarization of the radiation patterns are also observed to be very small.