An Optimized Checkerboard Structure for Cross-Section Reduction: Producing a Coating Surface for Bistatic Radar Using the Equivalent Electric Circuit Model

In this article, checkerboard metallic surfaces are analytically studied for nonabsorptive radar cross-section (RCS) reduction. The patch periodic elements are modeled with the equivalent electric circuit. The circuit model is exploited to achieve an improved reflection phase from the unit cell. By employing the phase difference from the edges of two frequency-selective surfaces (FSSs), a destructive interference takes place. In the wavescattering scenario, a fitness function is derived for RCS reduction (RCSR). The optimum reflection phase for an incident wave frequency interval is obtained with the help of circuit model analysis. A genetic algorithm (GA) is used for reflection phase optimization. An optimum checkerboard is designed based on the analytical and optimization methods. The checkerboard is constructed with two different patch widths as the optimum board to realize a phase difference condition in two dimensions. The designed board is numerically studied for both polarizations, bistatic RCS, and an incident angle span. After evaluating the numerical solution, the designed checkerboard surface is fabricated. Experimental observation validates the analytical results. The studied board uses a wellknown periodic surface and has a concrete analytical basis, optimum design procedure, bistatic RCSR, and far-field investigation.