Huygens Metasurface Lens for W-Band Switched Beam Antenna Applications

Abstract

Switched beam antennas provide an efficient and cost effective alternative to complex phased array and digital beam forming techniques. In this paper, we present the design and characterization of an electrically thin Huygens metasurface lens operating at 83 GHz with high transmission efficiency and we demonstrate its applicability to switched beam antenna applications. We accurately characterize the 3D scattered field distribution and determine the focal length and transmission efficiency of the lens by near-field scanning. A model based on ideal Huygens sources is used to predict the focal performance, allowing the geometrical measurement parameters to be determined in advance. Finally, the ability of the lens to operate as a switched beam antenna is experimentally verified by exciting it with an omnidirectional waveguide antenna placed at different positions. The experimental results are in very good agreement with numerical simulations, showing steering angles up to 12? while keeping the side lobe level below-15 dB.