Application of boundary element method to the analysis of cutoff wavenumbers of ridged rectangular waveguides and ridged circular waveguides

The computation of the cutoff wavenumbers using the boundary element method (BEM) is presented in this paper. Through discretization, the scalar integral equation Green's function is used to determine the spectrum mode in the ridged waveguide. These equations are transformed into a eigenvalue equation, with the eigenvalues as the resonant frequencies, using the Galerkin method. Electric field plots are presented for ridged rectangular waveguides and ridged circular waveguides. Results are given and compared with published data.