Huygens' metalens antenna fed by Integrated Substrate Gap Waveguide antenna

In this paper, a high-gain lens antenna with Huygens' metasurface is proposed. Firstly, a Huygens' metasurface unit is designed, which can achieve a phase coverage of 325° in the transmission amplitude range of -1dB at 28GHz, and only needs a layer of dielectric plate. A metalens with a diameter of
$\boldsymbol{10.2\lambda_{0}\times 10.2\lambda_{0}}$
is designed based on the proposed element. The feed antenna adopts super surface antenna based on integrated substrate gap waveguide (ISGW) design, which has higher gain and bandwidth compared to conventional microstrip patch antenna. The simulation results show that the impedance bandwidth of the metalens antenna is 23.05GHz-30.15GHz, with a relative bandwidth of 26.7%. The peak gain of the antenna is 27.1dBi, and the 3dB gain relative bandwidth is 23.8%. The SLL of the metalens antenna is lower than -25dB from 26GHz to 30GHz. The overall performance of the antenna is excellent.