BPSO and Staggered Triangle Layout Optimization for Wideband RCS Reduction of Pixelate Checkerboard Metasurface

A wideband radar cross section (RCS) reduction method is proposed based on checkerboard metasurface, which is one of the promising solutions for higher efficiency and better performance. First, the metasurface is pixelated into a checkerboard, and the algorithm of binary particle swarm optimization is introduced for the artificial magnetic conductor (AMC) pattern design on the checkerboard metasurface. In the proposed method, only one AMC pattern is designed to achieve the phase difference with dielectric substrate that is the necessary condition in RCS reduction, which significantly simplifies the AMC design and greatly improves its designing efficiency. Second, the number of elements in metasurface, which constitutes the unit cells, is optimized by full-wave simulation. Furthermore, we exploit unit cells under a staggered triangle layout for better grating lobe and vertical RCS reduction, and it improves the angle and polarization stability effectively compared with the traditional square layout. Finally, the simulation and experiment results demonstrate the effectiveness of the proposed wideband RCS reduction design.