A Low-Profile Dielectric Resonator Antenna with Compact-Size and Wide Bandwidth by Using Metasurface

Abstract

A dielectric resonator antenna (DRA) with the loading of metasurface (MS) is proposed for low-profile, wide-bandwidth and compact-size. Firstly, an MS structure consisting of 6×6 periodic metallic patch cells is loaded above the DRA. It aims to excite an additional TM surface wave above the fundamental TE111 mode of the rectangular DRA. Then, the shorting walls are printed on two sides of the dielectric, thus moving down the operating frequency with respect to its TM surface wave mode. As such, the bandwidth of the antenna is significantly widened with compact-size under the operation of TE111 and TM surface wave modes. Finally, the proposed DRA with enhanced performance is fabricated and tested. The results show that an impedance bandwidth of the antenna is dramatically increased to about 17.2%, covering the frequency range from 1.75 to 2.08 GHz, which is about 9.6 times wider than the traditional DRA at the same thickness (1.8%). Besides, it still maintains the broadside radiation pattern with stable gain of around 6.6 dBi and fairly low cross polarizations of below -26 dB. Particularly, the overall size of the radiator still maintains as small as about 0.32λ0 × 0.32λ0 × 0.044λ0. It should be noted that the analysis of the antenna is carried out by using Ansys HFSS software version 14.0 and ADS 2011.