Wideband Dual-polarized Programmable Metasurface for Tunable RCS Reduction

A dual-polarized programmable metasurface (DPM) is proposed in this work as a mean of attaining wideband tunable radar cross section (RCS) reduction. A top radiating metal patch layer, two substrate layers, a middle ground layer and a bottom circuit-routing layer make up the DPM element. Due to the structural central symmetry, switching both x-axis or y-axis positive-intrinsic-negative (PIN) diodes independently results in the dual-polarized 1-bit phase differences that are within 180° ± 20° over the whole x band. A 20×20 DPM is built using this element. The simulated far-field results indicates the proposed DPM provides a flexible wideband control of 0-20 dB RCS reduction utilizing alternative spatial coding schemes, for two orthogonally linearly polarized incident waves. Even in the case of oblique incidence, it also shows good modulation performance.