A model for predicting the scattering by a junction of three dielectric slabs

The aim of this work is to develop a UAPO based model for predicting the scattering by a junction of three dielectric slabs when illuminated by an incident plane wave. The geometrical optics (GO) response is obtained by extending the approach developed by Burnside and Burgener for lossless slabs (Burnside, 1983). The diffraction contribution is evaluated by using a PO approximation of equivalent surface currents densities and by performing a uniform asymptotic evaluation of the resulting radiation integral. Its resulting analytical expression is given in terms of the transition function of the uniform theory of diffraction (UTD) (Kouyoumjian, 1974), and is easy to handle and to implement as subroutine also in complex computer codes. Simulations are presented to demonstrate the validity of the proposed approach.