Computer simulation of wave scattering from three-dimensional conducting random surfaces

Numerical simulation studies had been carried out by the conjugate gradient method to compute the solutions of the field integral equation for three-dimensional, perfectly conducting, Gaussian, random rough surfaces. The rate of convergence of the conjugate gradient method was fundamentally controlled by the root mean square (rms.) surface slope. Solutions computed using this method result in a significant reduction in CPU running time compared to those using direct methods, such as the Gaussian Elimination method. The validity of the numerical results of backscattering coefficients is verified by comparing simulation results with Kirchhoff theory, small perturbation theory, and Integral Equation methods at their valid regions. The efficiency and versatility of the numerical simulation algorithm as a practical tool to study rough surface scattering is demonstrated.