A Focusing Meta-surface with High Transmittance and Low Profile for Millimeter-wave Lens Antennas

A focusing meta-surface lens using layered phase compensation is proposed. The meta-surface is designed to converge the propagating plane waves to the focal point with high transmittance in a compact size of
$\mathbf{103}.\mathbf{5}\ \mathbf{mm}\times \mathbf{103}.\mathbf{5}\ \mathbf{mm} \times \mathbf{1}.\mathbf{524}\ \mathbf{mm}$
. A horn operating at 24 GHz is placed at the focal point of the meta-surface as the source for generating mmWaves, which propagate through the meta-surface to form plane waves with well-defined radiation patterns. Compared with a single horn antenna with gain 10.9 dBi, the lens antenna can obtain enhanced gain as high as 25.9 dBi, meanwhile the - 17.6 dB sidelobe is low as well. The proposed focusing meta-surface lens with low profile, high gain, low sidelobe provides a good option for millimeter-wave communications.