Scattering from Variable Resistive and Impedance Sheets

Abstract

Scattering from variable planar resistive and impedance sheets with one dimensional variations is studied in this report. An approximate solution is obtained using a perturbation technique in the Fourier domain. It is shown that the solution for a variable resistive sheet with resistivity R (x) is identical to the solution for an impedance surface with impedance η (x) by replacing R(x) with η(x)/2. The solution for the induced current on the sheet in terms of the resistivity (impedance) function is given in a recursive form. The closed form nature of the solution enables us to study the statistical behavior of the scattered field when the perturbation function is a random process. The solutions based on the perturbation technique are compared with those obtained by other methods such as the moment method for periodic resistive and impedance sheets (Appendix A), numerical solution of the integral equation for scattering from a dielectric object above a resistive sheet, and GTD for the problem of impedance insert.