Numerical Calculation of Diffraction Coefficients in the Electromagnetic Wave Scattering by a Curvilinear

Abstract

A hybrid method of electromagnetic field calculation in the problem of ray congruence diffraction by a curvilinear impedance surface with edge is suggested. It uses jointly the finite element method and the uniform asymptotic theory with numerical diffraction coefficients. The hybridization procedure proposed allows computing several highest terms of the edge wave asymptotic expansion, the excitation coefficients of several highest creeping or whispering gallery modes, and the excitation coefficients of the impedance surface waves. The electric dipole field diffraction by a parabolic reflector with the impedance shaded surface is solved using the method proposed, and the obtained solution is compared to that obtained with the finite element method.