Design of Checkerboard AMC Structure for Wideband RCS Reduction

Abstract

In this paper, we propose a method for designing checkerboard surfaces using strategically placed artificial magnetic conductors (AMCs) for wideband radar cross section (RCS) reduction. The theoretical analysis shows that the reflection phases of the two AMCs should be linear. The cancelation conditions of checkerboard structure are analytically derived using an equivalent transmission line model, and the ideal impedance conditions of the two AMCs are obtained, which serve as guidance to select patterns of two AMCs unit. A planar checkerboard surface with two kinds of AMC elements is designed for wideband RCS reduction. A 10 dB RCS reduction is observed for approximately 91.5% of the relative bandwidth (3.77–10.14 GHz) under normal incidence. A prototype of the proposed checkerboard surface is fabricated, and the measurements results show good coincidence with the synthetic studies. The bistatic RCS of the checkerboard surface is considered for both transverse electric and transverse magnetic polarizations under oblique incidence.