Passivity Correction of Loewner Macromodeling using Spectral Zeros Method

This paper presents a passive macromodeling technique using the Loewner matrix (LM) algorithm for modeling distributed circuits characterized by frequency-domain data. A methodology is described based on a frequency point selection technique, which increases the likelihood that the unreduced Loewner matrices form a passive system. Then the proposed algorithm reduces the LM descriptor state space (DSS) matrices using the spectral zeros method (SZM). A key feature of the spectral zeros method is that it preserves the passivity of the reduced system, if the original system is passive. A numerical example is provided to illustrate the validity of the proposed work.