Miniaturized Broadband dual-polarized Dielectric Resonator Antenna Using Characteristic Modes

This paper presents a compact and broadband dielectric resonator antenna (DRA) with dual polarization radiation. To achieve a compact size the high permittivity technique is used which results in a narrow bandwidth. In an effort to improve the resultant bandwidth of the DRA, the characteristic mode analysis (CMA) is used. First, a conventional rectangular DRA is analyzed by CMA, as a result, two pairs of degenerate modes resonating at two different frequencies (0.41GHz and 0.61 GHz) are selected for having dual polarization performances. Based on that and to adjust the selected modes so that to merge them for broadband radiation, the DRA's shape has been changed to a cross-notch shape with a size of 0.2 lambda x 0.2 lambda. The simulation results show a bandwidth of 20.6%, a gain of 5dBi, and high isolation of more than 50 dB. Having these features, the proposed antenna can be of great use in massive MIMO antenna applications in the low band (<1GHz).