Waveguide Components Design in Presence of Complementary Modes

"This paper presents a procedure to design passive waveguide components taking into account the presence of complementary modes in the formulation. The algorithm, based on the Boundary Element Method (BEM), solves the wave equation for each discontinuity plane using two different formulations (TE and TM). The complete waveguide structure is obtained by cascading all discontinuities. The scattering parameters for a rectangular waveguide transformer are presented and it is shown to be computationally affordable."