Digital 2-bit metasurfaces with coding orientation of anisotropy for RCS reduction

In this work the radar cross section (RCS) reduction using 2-bit digital anisotropic impedance metasurfaces (MSs) consisting of four types of modules is investigated. Modules are differed by orientation of anisotropy and are described by digital bits of “00”, “01”, “10”, and “11”. Monostatic and bistatic RCS diagrams for two on differently coded, 2-bit digital coatings consisting of 8×8 modules are compared. The levels of monostatic RCSs with respect to the metal reference with the same dimensions; the number and the propagating direction of intense diffraction lobes in the bistatic RCS diagrams are evaluated. The possibilities of considered 2-bit and 1-bit digital coatings for reduction of RCS on co- and cross-polarizations are also compared.