A wide-angle scanning leaky-wave antenna loaded with a wideband metasurface

Phased antenna arrays suffer from a degradation in performance when being scanned to the horizon due to the effects of mutual coupling. A classical technique used to help alleviate this issue is wide-angle impedance matching (WAIM), which introduces a dielectric slab above the array, effectively acting as an impedance matching network. Here, we present a WAIM metasurface over a leaky-wave antenna comprising a pair of slotted substrate integrated waveguides, fed with a wideband coupler. It is shown that the introduction of a metasurface over this leaky-wave antenna results in a 2-3 dB improvement as the beam is scanned from 40° to 73° off broadside, over a 2 GHz frequency range centered about 11.2 GHz.