A surface integral equation method for the finite element solution of waveguide discontinuity problems

The surface integral equation method, which is typically used in the finite-element solution of open-region scattering problems, is applied to the solution of waveguide discontinuity problems. The major advantage offered by the surface integral equation approach over other methods is that it allows the mesh-truncating boundaries to be brought as close to the discontinuity as possible, thus helping to reduce the size of the system matrix. Unlike the mode-matching technique, the surface integral equation formulation does not require the solution of any auxiliary matrix system. Numerical results are presented to illustrate the validity of the formulation