Roughly Impedance-Matched Scatterers Constructed With Magnetodielectric Cells

Abstract

The monostatic theorem of Weston states that a null radar cross section (RCS) will be observed for objects with rotational symmetry that are impedance matched to their host medium, i.e., that have their material parameters $\varepsilon_r = \mu_r$ . A study of the generalization of this result applied to heterogeneous magnetodielectric (MD) scatterers is presented. The entire object of interest is divided into a set of small cubical unit cells in a three-dimensional checkerboard format, i.e., two different materials are distributed alternately in lego-like designs. Numerical computations are presented to compare the RCS levels of perfectly impedance-matched scatterers and their lego-based equivalents. The degree of homogenization that can be attributed to these heterogeneous scatterers for a variety of double positive material choices, including extreme values, is addressed specifically in relation to their satisfaction of Weston’s theorem.