Comparative Wiener–Hopf analysis of the radar cross sections of two canonical, parallel-plate waveguide cavities with material loading

This paper presents a review of the authors' research on the radar cross section (RCS) of two canonical waveguide cavities. A rigorous RCS analysis is carried out using the Wiener-Hopf technique for the two-dimensional cavities formed by a terminated, semi-infinite parallel-plate waveguide with three-layer material loading (cavity I) and a terminated, finite parallel-plate waveguide with three-layer material loading (cavity II). Both <i>E</i>- and <i>H</i>-polarizations are considered. Taking the Fourier transform of the unknown scattered field and applying boundary conditions in the transform domain, these problems are formulated in terms of the simultaneous Wiener-Hopf equations. The Wiener-Hopf equations are solved via application of the factorization and decomposition procedure, leading to exact and approximate solutions. Taking the inverse Fourier transform of the solution in the complex domain, a scattered field in the real space is explicitly derived. For the region inside the cavity, the scattered field is expressed in terms of the waveguide modes, whereas for the region outside the cavity, a scattered far field is derived using the saddle point method. Numerical examples on the RCS are presented for various physical parameters, and far-field scattering characteristics of the cavities are discussed in detail.This article is part of the theme issue 'Analytically grounded full-wave methods for advances in computational electromagnetics'.