Inverse Design of Broadband AMC Metasurface for RCS Reduction Using Simulated Annealing

In this study, we present a novel design methodology for unit cells in chessboard metasurfaces, aimed at reducing the radar cross-section (RCS) for linearly polarized waves. The design employs rotational symmetry and incorporates ten continuous parameters to define the metasurface units, enabling the creation of flexible 2D structures. The geometrical parameters of the two units are then optimized using a simulated annealing (SA) algorithm to achieve a low RCS chessboard metasurface. Following optimization, the properties of metasurface were ex perimentally verified. Experimental results show a significant RCS reduction of 10 dB within the 7.6–15.5 GHz range, with a peak reduction reaching-28 dB at normal incidence. For bistatic RCS, the metasurface effectively scatters incident waves into four distinct lobes. The proposed method offers an alternative strategy for the inverse design of low RCS metasurfaces and can be extended to applications in polarization control, phase gradient manipulation, and transmissive metasurfaces.