Reconfigurable Ultrathin Beam Redirecting Metasurfaces for RCS Reduction

A reconfigurable metasurface concept is proposed for dynamically tuning the direction of the maximum radar cross section (RCS). The basic unit cell of this metasurface is a loaded mushroom-type structure. By capacitively loading the unit cells, the reflection phase across the metasurface can be controlled, thus allowing incident plane waves to be scattered in any arbitrary direction. As a consequence, the RCS of the metasurface can be considerably reduced for the specular direction. Unlike previous static design approaches that yield fixed beam patterns, the reconfigurable aspect of the metasurface allows dynamic control over the placement of the RCS peaks and/or nulls.