HIGH-FREQUENCY DIFFRACTION BY A STRIP LOCATED AT THE INTERFACE BETWEEN 2 DIFFERENT MEDIA

The E-polarized plane wave diffraction by a perfectly conducting strip located at the plane interface between two different media is analyze d by the Wiener-Hopf technique. Applying the boundary conditions to th e integral representations for the unknown scattered field, the proble m is formulated in terms of the modified Wiener-Hopf equation (MWHE), which is reduced to a pair of simultaneous integral equations via the factorization and decomposition procedure. The integral equations are solved asymptotically for large strip width via the method of successi ve approximations leading to the first, second and third order solutio ns, which are valid at high frequencies. The scattered far field expre ssion is derived by taking the inverse Fourier transform and applying the saddle point method. It is shown that the high-frequency scattered far field comprises the geometrical optics field. the singly, doubly and triply diffracted fields and the lateral waves. Numerical examples of the radar cross section (RCS) and the lateral waves are presented, and the far field scattering characteristics are discussed in detail.