TIME-DOMAIN SURFACE IMPEDANCE BOUNDARY-CONDITIONS OF HIGH-ORDER OF APPROXIMATION

The problem of diffusion of transient electromagnetic field into a los sy dielectric homogeneous body is solved by using the perturbations me thod in the small parameter p, equal to the ratio of the electromagnet ic penetration depth and characteristic dimension of the body. Time an d frequency domain solutions for the tangential component of the elect ric field and the normal component of the magnetic field on the smooth curved surface of the body (the surface impedance boundary conditions - SIBCs) are obtained with the accuracy up to O(p(4)). It is shown th at the proposed SIBCs in the frequency domain generalize well-known Le ontovich's and Mitzner's boundary conditions that provide approximatio n errors O(p(2)) and O(p(3)), respectively. A numerical example of usi ng the high order SIBCs with the surface integral equations in time do main is considered to illustrate the method.