Modal Expansion Analysis of T-Shaped Waveguide

Abstract

The T-shaped waveguide (T-waveguide for short) is a new kind of wideband waveguide which is easier to fabricate than conventional wideband waveguides. This paper presents the modal expansion analysis of the T-waveguide. The T-waveguide is first divided into four rectangular domains. The electromagnetic fields in each domain are expressed by suitable mode functions. The continuity of tangential electromagnetic fields along the interface of neighboring regions is enforced by the Galerkin's matching process and a matrix equation is thus derived. The cutoff wavenumbers of the T-waveguide are then found from the matrix. The results are in good agreement with those obtained by CST Microwave Studio. The proposed method provides fast calculation of the T-waveguide cutoff wavenumber, which is of guiding significance to the design of T-waveguide.

An Efficient Automatic Mesh Generator With Parabolic Arcs in Julia for Computation of TE and TM Modes for Waveguides

“…In recent times, these problems have been widely highlighted and explored [9], [10]. Techniques such as the BEM [10] and modal expansion analysis [41] have been used to address these problems numerically. To resolve these eigenvalue problems (EVPs), there is a tremendous need for an outstanding numerical technique.…”

“…The concern here is about higher order polynomial approximation for the physical variable, and this will naturally contain four, five and six nodes for cubic, quartic and quintic elements along the curved boundary. It is clearly explained that how to choose the four nodes of cubic element, five nodes of quartic element and six nodes of quintic triangular element along the curved side so that the curve represents a parabolic arc as nearly as possible [33], [37]- [41].…”