The numerical calculation of two-dimensional rough surface scattering by the conjugate gradient method

Numerical simulation studies have been carried out by the conjugate gradient method to compute the solutions of the field integral equation for two-dimensional, perfectly conducting, Gaussian (normal), randomly rough surfaces. The rate of convergence of the conjugate gradient method is fundamentally controlled by the root mean square (r.m.s.) surface slope (gradient). Solutions computed using this method result in a significant reduction in CPU running time compared to those by direct methods, for example Gaussian Elimination method. The backscattering coefficients were calculated and compared with the small perturbation method results and Kirchhoff method results, and a good approximation resulted.