Beam-Squinting Reduction of Leaky-Wave Antennas Using Huygens Metasurfaces

A novel approach is presented to reduce the beam squinting of radiating structures with emphasis on leaky-wave antennas (LWAs). This is achieved by taking advantage of the interesting frequency-dependent variation of the generalized law of refraction in metasurfaces, in combination with the beam-squinting characteristics of LWAs dictated by their dispersion diagram. An X-band coplanar waveguide leaky-wave antenna (CPW-LWA) and a Huygens metasurface are fabricated and experimental results verify that the proposed concept can reduce the beam squinting of the LWA by 50% over a 10% bandwidth at angles around broadside. The proposed method is shown to be an excellent approach to build simple, low-profile, and lowcost communication systems composed of LWAs with low beam-squinting characteristics over a reasonably wide frequency range.