E-Polarization Diffraction by a Thick Metal-Dielectric Join

Abstract

A solution of the diffraction from a dielectric-metallic join due to an incident E₁ -polarized plane wave is presented. Direct diffraction, coupling, launching, and reflection subproblems associated with a loaded parallel-plate waveguide are first treated via the dual integral equation method. The results are subsequently combined in the context of the generalized scattering matrix formulation to obtain the diffraction from the truncated parallel-plate waveguide with a recessed stub and a dielectric loading extending to infinity. The stub is then restored to the waveguide mouth to obtain the diffraction by the dielectric-metallic join. As expected, the final expressions involve several Wiener-Hopf split functions and an efficient numerical technique for their evaluation is given in an appendix. The convergence of the solution with respect to the number of included modes is examined and a number of scattering patterns are presented.