Millimeter Wave Metasurface Lens for Gain Enhancement

Design of Metasurface (MS) lens operating at 28 GHz frequency is proposed in this work for gain enhancement with focused beam in broadside direction. The transmission type MS lens consists of Huygens' unit cell arranged in a 15×15 matrix in order to provide phase compensation to the incidenting phase profile from the feed. The unit cell provides more than 360° transmission phase coverage with a single dielectric substrate layer. The overall antenna system consists of a feed horn and a planar MS lens with hyperbolic phase profile. The size of the lens is 7.28 λ0×7.28 λ
0
× 0.14 λ
0
(where, λ0is free space wavelength at operating frequency i.e. 28 GHz). The proposed MS lens improves the gain of Ka-band pyramidal horn by 8.4 dB, resulting in a broadside gain of 23.40 dBi. This short focus high gain antenna system can be used for various 5G applications.