Electromagnetic Band-Gap Leaky-Wave Antennas Based on Grounded Dielectric Lattices

In this paper, we present the design of an Electromagnetic Band-Gap (EBG) leaky-wave antenna consisting of a two-dimensional lattice of dielectric cylinders above a ground plane. The radiation from an electric line source embedded in the EBG open waveguide is modeled by means of suitably excited leaky modes. An in-depth dispersive analysis has showed how a multiplicity of modes, both guided and leaky, propagates within the structure. However, by properly placing an elementary source within the lattice, a single leaky mode of the EBG structure has shown to provide a highly convergent representation of the radiated far field. Based on the knowledge of the leaky-mode attenuation constant, it is possible to truncate the structure longitudinally in order to obtain a radiation efficiency of 96 %. This study led to the design of an antenna operating at a frequency belonging to the 5G millimeter-wave bands. Excellent agreements have been obtained between the theoretical results based on leaky-wave radiation and ad-hoc and full-wave commercial simulators.