Improving accuracy after stability enforcement in the Loewner matrix framework

Enthalten in
IEEE transactions on microwave theory and techniques 
Volume
70
Issue
2
Start Page
1037
End Page
1047
Citation
IEEE Transactions on Microwave Theory and Techniques 70 (2): 1037-1047 (2022-02-01)
Publisher DOI
10.1109/TMTT.2021.3136234
Scopus ID
2-s2.0-85122568429
Publisher
IEEE
The Loewner matrix (LM) is a powerful macromodeling technique that uses sampled data in the frequency domain for representing dynamical systems in a descriptor form. As stability cannot be enforced during the construction process, a postprocessing step is required to ensure a stable macromodel, which reduces its accuracy. In this article, two techniques are incorporated and evaluated with the LM framework in this postprocessing phase. The first one is an efficient sign-pole-flipping technique for stability enforcement. The other one is a matrix updating technique applied after the stability enforcement of the model. The proposed approaches are evaluated using data in the scattering parameter form for printed circuit board via interconnects examples and an electromagnetic shielding structure and compared to the state-of-the-art stability enforcement algorithms. For completeness, we will also compare the results with respect to the macromodels created by the vector fitting algorithm. It was found that by the proposed flipping and matrix updating approaches, an error reduction by a factor between 2 and 20 was achieved with respect to the previously reported methods.
Schlagworte
Circuit stability
Descriptor systems
Eigenvalues and eigenfunctions
Frequency-domain analysis
Loewner matrix (LM)
macromodeling
Matrix decomposition
passive macromodels
Stability criteria
stability enforcement.
Transfer functions
Transmission line matrix methods
DDC Class
600: Technik