Metamaterial-based 2D multi-beam broadband Luneburg lens antenna

A metamaterial surface composed of non-resonant circular complementary closed ring resonators is designed to obey the refractive index of a Luneburg lens. An array of planar slot antennas placed at the periphery of the lens is used at wave launchers. A prototype of the lens associated with the feed structures has been fabricated using standard printed circuit board (PCB) technology. Measured far-field radiation patterns have shown directive beams in H-plane over the [8 GHz-12 GHz] frequency range. Furthermore, this metasurface lens antenna has demonstrated beam-scanning with a coverage of up to 120°. Far-field measurements agree qualitatively with calculated near-field distributions.