Ultrathin Metamaterial Screens With Nonuniform Patches for Reflectivity Reduction From Metallic Surfaces

This paper presents a class of ultrathin metamaterial screens for microwave reflectivity reduction from metallic surfaces. The screens consist of a highly conductive sheet with periodic patterns on top of a thin grounded lossy substrate. The periodic patterns of the screens are composed of nonuniform patches. It is found that the considered screens exhibit about 60% larger working bandwidth than those with uniform patches. A simple analytical equivalent circuit is also derived for mechanism understanding and quick design for the screens.