RCS Reduction Based on Concave/Convex-Chessboard Random Parabolic-Phased Metasurface

A hybrid design method for broadband radar cross section (RCS) reduction based on reflection diffusion is proposed and successfully demonstrated. To this end, we first analyze the scattering behavior of full parabolic-phased metasurface and find out its weaknesses in achieving perfect diffusive patterns. Then, we alleviate the issue of full parabolic-phased method through hybridizing two strategies, i.e., concave/convex chessboard arrangement and random focal lengths. The proposed hybrid design makes the phase profile aperiodic without any mirror symmetry, which is the key for achieving perfect diffusive scattering behavior within a wide operation band. The numerical and experimental results show that our proposed design features broadband, polarization insensitivity, and wide incidence angle and can efficiently decrease the RCS more than 10 dB within 7.8-23.2 GHz. Our approach comprehensively solves the issues of narrow band, high bistatic RCS value, time-consuming optimization process, and sensitivity to different polarization and incident angles, promising great potential in stealth applications.