Ridge-gap waveguide slot antenna with ENZ medium for millimeter-wave MIMO applications

In this paper a new technique is proposed to obtain a two-dimensional beam-titling radiation pattern for millimeter-wave applications at 60 GHz. The proposed technique consists of a ridge-gap waveguide slot antenna as a TM source. To tilt the main-beam direction in the E and H-planes of the slot antenna, a 3×5 arrays of anisotropic epsilon-near zero (ENZ) metamaterial unit-cells is designed. The simulation results confirm that when a 3×5 arrays of ENZ unit-cells are integrated vertically over the slot antenna in the off-axis, the beam radiation deflects in the E and H-planes by 30 degrees, simultaneously, at 60 GHz. The antenna gain corresponds to 10.8 dBi at 60 GHz with loading ENZ unit-cells.