Wideband Monostatic/Bistatic RCS Reduction Using Optimized 1-Bit Coding Metasurface

The 1-bit coding metasurface is employed in this paper to demonstrate a technique for decreasing radar cross-section (RCS) in both monostatic and bistatic levels that has been optimized using a binary particle swarm optimization (BPSO) algorithm. The configuration of the design comprises two unit cells, specifically a square and a circular ring, represented as elements ‘0’ and ‘1’. The reflection phase between these unit cells exhibits a phase difference of approximately 180° ± 37°. This design operates within a frequency range of 22.5–30 GHz and achieves an RCS reduction of less than − 10 dB. The design of the coding element utilizes a cost-effective F4B substrate with a thickness of 1.5 mm. The BPSO algorithm, in conjunction with array theory, is employed to determine the optimal positioning of unit cells within the subarray to achieve wideband RCS reduction. Compared to the conventional checkerboard metasurface, the monostatic RCS reduction achieved by the optimized coding metasurface exhibits a wider bandwidth. Furthermore, the performance of the optimized metasurface is evaluated in a bistatic scenario at 27.5 GHz, demonstrating significant RCS reduction when compared to an equivalently sized metallic plate and checkerboard pattern. The simulation results indicate that the optimized coding metasurface presents a feasible solution for achieving significant RCS reduction in both monostatic and bistatic scenarios.