Design of Nonresonant Metasurfaces for Broadband RCS Reduction

A design method using simple patches with nonresonant mode to achieve broadband phase-gradient metasurfaces of reflective type is proposed and an example to apply it for radar cross section (RCS) reduction is given. The method is based on treating the patch in an element as a pixel and the phase differences are obtained by setting the pixels to be empty or full. As only two states can be guaranteed for a single element, super cell concept and multilayer configuration are introduced to improve the performance. A design example of reflective RCS reduction structure with the -10 dB bandwidth of 5.3-18 GHz is given to prove the efficiency of the method.