A Checkerboard Metasurface for Ultra-wideband Radar Cross Section Reduction

I In this paper, a checkerboard metasurface is designed and characterized for ultra-wideband radar cross section (RCS) reduction. The metasurface is formed of two kinds of elements with different configuration. By appropriately selecting the sizes of basic unit cells which based on minkowski ring patch and square ring patch respectively, a 180 degrees +/- 37 degrees reflection phase difference between two unit cells is obtained over 8.1-22.7 GHz (94.8% bandwidth). The metasurface based on the two unit cells is capable of altering the direction of the fields scattered by a target to four main directions deviating from normal direction, resulting in an ultra-wide frequency band RCS reduction. The 7.5 dB RCS reduction is obtained over 8.6 GHz-22.9 GHz (94.5% bandwidth) by comparing to an equal-sized perfect electric conductor (PEC) surface. Full-wave simulations of monostatic RCSs of the metasurface and the equal-sized PEC surface verify the characteristic.