Compact dielectric resonator antenna with bandwidth enhancement via loading of shorting pins

Abstract

A novel compact cylindrical dielectric resonator antenna (DRA) with improved bandwidth is proposed in this study. By loading the shorting pins around the nodal line of electric fields of TM011 mode of the DRA, an additional shorting-pin mode could be excited for the antenna, while keeping an almost constant frequency of TM011 mode. After that, the DRA loaded with two, three, and four shorting pins is further studied. The results indicate that the resonant frequency of the shorting-pin mode is progressively pushed up by increasing its number. With these arrangements, an improved-bandwidth is obtained for the DRA loaded with four pins. Finally, the proposed DRA is fabricated and measured to validate the predicted performances. The results show that the DRA has gained an enhanced-bandwidth (|S11| < –10 dB) of about 17% (3.65–4.33 GHz) under the radiation of dual modes, while keeping the stable conical radiation patterns. Most importantly, the height and diameter of the dielectric radiator are maintained as small as 0.09 and 0.32 free-space wavelength, respectively.