Designs of Notch Filters and Absorbers with Overmoded Waveguides
Date Issued
2014
Date
2014
Author(s)
Wei, Li-Tien
Abstract
An overmoded waveguide is presented through changing the dimension of width. We put a dielectric in middle of the waveguide in order to excite higher order modes. Because of higher order modes can only exist in the wider dimension of width, effectively form a cavity in the waveguide. Then we design notch filters and absorbers by the interference conditions of two modes composition. We choose TE10 mode and TE30 mode as two operating modes in K-band. At the beginning of this work, we simulate the frequency responds of different structures by the simulation program “HFSS”, then put the design structure into the real waveguide for testing. Finally we compare the differences between the simulation results and measurement data and take the temporal coupled-mode theory into consideration for further optimization of the design. We also measure the permittivity and loss tangent of the dielectric in rectangular waveguide for simulation settings.
Subjects
Overmoded waveguide
notch filter
absorber
temporal coupled-mode theory
complex permittivity measurement
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-103-R01941095-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):826f8d0afa8741278bd81eef1f17d21a