Wide-angle flat metasurface corner reflector

Abstract

In this paper, a wide-angle flat corner reflector based on the multiple phase gradient modulated metasurface is proposed and demonstrated. Through designing the related gradient phase, the propagation direction of the reflected electromagnetic wave is just opposite to the propagation of the incidence wave based on the generalized version of the reflection law. This guaranteed a radar cross section (RCS) enhancement in the vicinity of this incidence direction. To derive a uniform mono-static RCS in a wide incidence angle domain, the flat metasurface corner reflector is decomposed into several regions with different areas, which are designed for RCS enhancing under wave incidence in different incidence directions. As an example, the metasurface corner reflector consisted of two different phase gradients operating over the X-band is designed to realize wide-angle RCS enhancement. The simulated results indicate that in the designed incidence directions, the reflected waves are all opposite to the incidence wave for both TE and TM polarized waves. To validate the RCS enhancement performances, the mono-static RCS of the designed metasurface corner reflector is measured. The measured results reveal good accordance with the simulations, and both demonstrated that the designed metasurface corner reflector obtains tremendous RCS enhancement performances in a wide-angle domain (−50°–50°) for both TM and TE polarized waves.