Localization and Identification of EMI Sources in Shielding Enclosures Based on a Two-Step Source Reconstruction Method

Localization and identification of unknown electromagnetic interference (EMI) sources in shielding enclosures is a great challenge due to the complex electromagnetic environment. In this work, a two-step source reconstruction method is proposed to address this issue. The actual EMI sources are initially modeled by equally distributed equivalent electric dipoles in the shielding enclosure. Effects of surrounding environments are rigorously incorporated using the numerical Green's function which bridges between the equivalent dipoles and planar scanned tangential magnetic near-field. Next, the initial equivalent sources are downsized via evaluating the contribution of each equivalent dipole. The parameters of remaining equivalent dipoles are updated by another source reconstruction process, in which additional equivalent magnetic dipoles are added to improve precision of the equivalent model. The locations and geometries of EMI sources in the shielding enclosure can be identified clearly in terms of the updated equivalent dipoles. Furthermore, the radiated emissions from individual EMI sources can be estimated accurately. The effectiveness of this approach is validated by representative numerical examples.