A Rigorous Numerical Comparison for Parameter Extraction Using Classical and Kullback-Leibler Formulations Illustrated with Full-Wave EM and Equivalent Circuit Models for Microstrip Filters

Numerical circuit parameter extraction (PE) is a key sub-process of space mapping (SM), which is used to efficiently optimize full-wave EM responses of microwave structures exploiting faster but inaccurate physics-based auxiliary models. Any improvement in PE has a positive impact on SM design optimization. In this paper, we apply for the first time a PE formulation based on the Kullback-Leibler distance to microstrip filters using their full-wave EM responses as targets. We perform a rigorous numerical comparison of PE based on the K-L formulation against PE using classical norms. Our results confirm a better PE performance using the Kullback-Leibler formulation than those obtained with traditional PE formulations.