Integral equation solution for truncated slab structures by using a fringe current formulation

Full-wave solutions of truncated dielectric slab problems are interesting for a variety of engineering applications, in particular patch antennas on finite ground planes. For this application a canonical reference solution is that of a semi-infinite slab illuminated by a line source. Standard integral equation (IE) techniques are not easily applied to this problem, since unknown equivalent currents have to be distributed on a semi-infinite domain. In this paper we present a surface/surface approach, applied to an IE which is based on a non-conventional formulation. More precise, the unknowns of this IE are the difference between the actual currents and the currents of the infinite structure (without truncation).