DIFFRACTION BY A TERMINATED, SEMI-INFINITE PARALLEL-PLATE WAVEGUIDE WITH FOUR-LAYER MATERIAL LOADING: THE CASE OF H POLARIZATION

The diffraction by a terminated, semi-infinite parallel- plate waveguide with four-layer material loading is rigorously analyzed for the H-polarized plane wave incidence by means of the Wiener- Hopf technique. Introducing the Fourier transform for the unknown scattered field and applying boundary conditions in the transform domain, the problem is formulated in terms of the simultaneous Wiener-Hopf equations. The Wiener-Hopf equations are solved via the factorization and decomposition procedure together with the use of the edge condition leading to exact and approximate solutions. The scattered field inside and outside the waveguide is evaluated by taking the inverse Fourier transform and applying the saddle point method. Numerical examples on the radar cross section (RCS) are presented for various physical parameters, and the backscattering characteristics of the waveguide are discussed.