Accelerate IEMI Evaluation in the Design Stage Using Parametric Vector-Fitting

Electromagnetic interference (EMI) evaluation necessitates a crucial first step: electromagnetic (EM) coupling analysis. The field-to-line coupling problem requires a self-consistent solution of the EM problem and the associated circuit. Efficient prediction of circuit responses is paramount for statistical or parametric analysis in EMI evaluation. This article employs parametric vector-fitting (VF) to analyze the EM coupling effect on microstrip lines in a perforated metallic enclosure. The EM coupling problem is converted into a circuit using Thevenin's equivalent circuit and VF, where a rational function with a common pole represents the transfer function at various incident directions. An intentional EMI source is introduced into the circuit in this way and is treated as a load-independent source. The results obtained from equivalent circuit methods exhibit consistency with those computed by full-wave solver for linear and nonlinear loads, showcasing superior time efficiency. The application of parametric VF in field-to-line coupling can expedite EMI evaluations during the product design phase.