Rectangular waveguide filter
The present example considers the rectangular waveguide filter proposed by P. Ibbs and M. Guglielmi in the September 1996 issue of Microwave Engineering Europe.
Rectangular waveguide filter.
The filter is built in a 19.5 x 9.525 mm rectangular waveguide. The irises separating consecutive waveguide sections are symmetric and span full height of the waveguide.
The input section is 19.05 mm long, the first and the second resonator sections are respectively 11.18 and 12.784 mm long. The fourth and the fifth resonator sections and the output waveguide section are of the same length as the second and the first resonator sections and the input waveguide section. Length and width of the following irises are: 11.05 mm and 2 mm, 8.01 mm and 1.96 mm, 8.01 mm and 2.86 mm, 8.01 mm and 1.96 mm, and 11.05 mm and 2 mm.

The described structure is symmetric, what allows us to enforce a magnetic symmetry plane along its symmetry axis and consider only a half of it. The magnetic symmetry plane is placed at Y=0, which is the filter's symmetry plane.
Rectangular waveguide filter project in QW-Modeller - half of the structure.
Rectangular waveguide filter project in QW-Modeller - magnetic symmetry plane enforced at the structure's symmetry axis.
The S-Parameters postprocessing is set from 10 GHz to 15 GHz with the frequency step of 0.01 GHz.
S-Parameters postprocessing configuration dialogue.
Reflection and transmission characteristics of the rectangular waveguide filter.
Distribution of time-maximum envelope of Ez field component at 12.39 GHz.
Distribution of time-maximum envelope of Ez field component at 11 GHz.