Metasurface with Strip-Shaped Phase Distribution Constructed by Rotation Slots for Backward RCS Reduction

A rectangular reflection-type metasurface for radar cross section (RCS) reduction is proposed. The metasurface can provide a strip discontinuous gradient phase distribution which can reflect incident waves in various directions. The rotation angle of the slots in rectangular unit cells is designed to get the strip-shaped gradient phase distribution. Simulation results indicate that the RCS can be reduced as large as 13.7dB under normal x-polarization incident waves at 13GHz. The introduction of strip phase distribution can reduce the backward RCS in the frequency range of 12G to 21G. RCS reduction is different at different frequencies due to the frequency dependent property of the gradient surface.