Electrodynamic analysis of eigenmodes in a rectangular waveguide with two L-shaped septa

The novel compact microwave SIW filter based on L-ridged rectangular waveguide

“…One of such waveguides is the rectangular waveguide with two L-ridges. [6] As it was shown in [2], the filters on L-ridged rectangular waveguide has in its transient characteristic not only the traditional resonant frequency but also the frequency of complete rejection (anti-resonance). This feature allows very high attenuation levels in filter stop-band.…”

“…[6] According to this method, the complex cross section area of a rectangular waveguide with L-shaped metal ridge ( Figure 1) is split into four partial rectangular regions.…”

“…the detailed description of matrix elements is given in [6]. By generating the determinant of the homogeneous system (5) and equating it to zero, the transcendental equation for calculation of cutoff wave numbers for TE-and TM-waves is derived.…”

“…[6] Substituting f j (x) in the system of the integral equations and applying Galerkin's method, the homogeneous system of linear algebraic equations with respect to U v jp is received, the system in a matrix form having the following view:…”

“…Using Galerkin's method [6] to solve the system of integral equations, the unknown functions f j (x) are represented in a series form with unknown coefficients on the full and orthogonal basis considering the features of electromagnetic field behavior near the sharp metal edge:…”