Analytical Waveguide Model Precisely Predicting Loss and Delay Including Surface Roughness

Journal article


Publication Details

Author(s): Lomakin K, Gold G, Helmreich K
Journal: IEEE Transactions on Microwave Theory and Techniques
Publication year: 2018
ISSN: 0018-9480
Language: English


Abstract

This paper describes an accurate modeling approach taking into account
the impact of surface roughness on both the attenuation and the phase
coefficients of the propagating TE10 mode in rectangular
waveguides. The proposed approach is based on a transmission line model
for waveguides and a general surface roughness model, which are both
derived from physical relations, i.e., Maxwell’s equations. Thus, it is
neither limited to explicit frequency bands nor to certain surface
profiles. Based on the proposed approach, the specific influence on the
propagation coefficient and the line impedance of a waveguide is
quantified in the typical transmission frequency region and also around
the cutoff frequency. Also, the roughness-dependent shift of the cutoff
frequency is covered by the proposed model and explained analytically.
Propagation characteristics predicted by the proposed approach
absolutely coincide with full-wave simulation by CST Microwave Studio
with the same input parameters. Furthermore, WR10 waveguide samples are
fabricated and their surface profile is characterized using a confocal
laser scanning microscope. Model predictions agree with electrical
measurements up to 90 GHz for the attenuation coefficient within ≤10%
and within 0.08% for the phase coefficient in the transmission region of
the waveguides. In addition, the difference between normally
distributed and arbitrarily distributed surface profiles is covered by
the model and pointed out in this paper at rigorous measurements even at
very smooth surfaces with root mean square-roughness of less than 300
nm. Finally, different techniques for utilization of this approach and
possible application fields are presented.


FAU Authors / FAU Editors

Gold, Gerald Dr.-Ing.
Professur für Rechnergestützten Schaltungsentwurf
Helmreich, Klaus Prof. Dr.-Ing.
Professur für Rechnergestützten Schaltungsentwurf
Lomakin, Konstantin
Lehrstuhl für Hochfrequenztechnik


How to cite

APA:
Lomakin, K., Gold, G., & Helmreich, K. (2018). Analytical Waveguide Model Precisely Predicting Loss and Delay Including Surface Roughness. IEEE Transactions on Microwave Theory and Techniques. https://dx.doi.org/10.1109/tmtt.2018.2827383

MLA:
Lomakin, Konstantin, Gerald Gold, and Klaus Helmreich. "Analytical Waveguide Model Precisely Predicting Loss and Delay Including Surface Roughness." IEEE Transactions on Microwave Theory and Techniques (2018).

BibTeX: 

Last updated on 2019-04-01 at 01:10