Gain and Bandwidth Improvement of a Cylindrical Dielectric Resonator Antenna (CDRA) by Using of Metamaterial Structures

Using metamaterials on the top of the antenna’s accordance to magneto-dielectric superstrate and near zero refraction index theories causes improvement of radiation efficiency and gain of antennas. In this article, two novel metamaterial unit cells are proposed for gain and bandwidth improvement of Cylindrical Dielectric Resonator Antenna (CDRA). The first metamaterial unit cell is a negative magnetic structure including two rings implemented on both sides of RT/doroid 5880 substrate with dielectric constant of 2.2. Besides, the second metamaterial unit cell is a Double Negative Structure (DNG) realized consisting of two rings printed in one side and a thin wire in other side of RT/doroid 5880 substrate. Two 7 7 arrays of proposed unit cells are considered and used as superstrate layers on the top of a CDRA. Also, the CDRA is made of RT/doroid 6010 material with dielectric constant of 10.2 working at the frequency of 10 GHz. Using proposed metamaterial structures as superstrate layers on the top of the CDRA causes gain and bandwidth improvement up to 3.3 dB and 4.8%, respectively. CDRA in the presence of proposed metamaterial superstrates are analyzed using a 3D full-wave simulator.