Optimum Design of a Beam-Forming Array of S-Shaped DRA Elements With a Superstrate on an SIW Feed for 5G Mobile Systems

In this letter, an array of dielectric resonator antennas (DRAs) is proposed for the fifth-generation mobile network. A novel S-shaped DRA is presented as array elements. The proposed configuration is achieved by making two symmetrical segments on a conventional rectangular DRA. The results show that in this configuration the higher order modes of antenna are excited, and therefore, the 3 dB gain bandwidth and impedance bandwidth of antenna are increased. The volume of the proposed DRA without ground plane is 0.38 λ
_g
³
. The proposed DRA provides maximum bandwidth and gain per unit volume compared to similar designs in the literature. Furthermore, the benefit of a mutual coupling (MC) compensation approach in a linear DRA array is investigated. The results show that the accuracy of a computed MC matrix is better at the resonance frequency relative to other frequencies. Also, the performance of a beam-forming algorithm is improved by using this matrix for compensating the MC effects. The proposed array is fabricated and its characteristics are measured. A very good agreement between the numerical and measured results is obtained.