Loewner Matrix Macromodeling for Y-Parameter Data With a Priori $\textbf {D}$ Matrix Extraction

Abstract

Macromodeling techniques using Loewner matrix (LM) interpolation were proposed recently as a way to generate time-domain macromodels based on simulated Y -parameters. These approaches scale very well with respect to the number of ports as well as the number of poles in the system. However, these methods become less efficient in terms of accuracy and passivity for Y -parameters obtained using electromagnetic simulators. In this paper, we propose an LM-based interpolation technique that is applicable for large-scale distributed systems described by full-wave Y -parameters. An algorithm to approximate and extract the port impedance matrix $\textbf {D}$ directly from the data is proposed. Additionally, an order selection scheme is proposed that results in an accurate macromodel while maintaining passivity. The efficiency and accuracy of the proposed approach is illustrated using comparisons with a standard technique.