Design of a low-RCS circularly polarized metasurface array using characteristic mode analysis

Abstract

In this paper, a novel design strategy for a circularly polarized metasurface antenna array that integrates low scattering and well-behaved radiation is proposed. Firstly, based on the Jerusalem cross-shaped patch, a metasurface element with 180° reflection phase difference under orthogonal normal incident waves is designed. The characteristic mode theory is utilized to analyze the metasurface element mode to excite the linear polarization radiation. Then, the metasurface antenna elements are arranged orthogonally in a 2×2 subarray and fed with a 90° phase difference, which achieves high port isolation, better circular polarization radiation and low scattering performance. Finally, the 4×4 array is fabricated and measured, and the good agreement between simulation and measurement verifies the effectiveness of the design method.