The scattering of electromagnetic wave at the finite-length branching in E-plane of rectangular waveguide

Abstract

The problem considered in this paper deals with a waveguide bifurcated by finite-length strip partition to two channels filled with dielectrics. The problem was solved by the piercing domain method. The whole complicated domain of the electromagnetic field determination is divided to two piercing regions and two semi-infinite regions when developing a full-wave algorithm. For piercing regions, the second Green’s formula was used to derive integral representations for total fields. Boundary conditions were used further at the ends of partition resulting in the integral equations of the Frendgolm second kind, in semi-infinitive regions. In these equations the Green’s functions of the layered filling media were used. The Galerkin procedure was used to reduce the system of integral equations to an infinitive system of linear algebraic equations solved by the truncation method.

A computer program was written to solve this problem. It has been tested, and numerical convergence has been verified. We have investigated the effect of the following parameters: geometrical size of partition (length and thickness), dielectric constant of the fillings, coupling of the propagating modes E₁₁, E₁₂ in the both channels, on the reflection coefficient of the incident mode E₁₁. The obtained results can be used for a microwave filter computer-aided design.