Assessment of Complex Radiated EMC Problems Involving Slotted Enclosures Using a 2-D Generalized Circuital Approach

A 2D version of the generalized circuital analysis (GCA) has been used along with the finite element method (FEM) to estimate both the radiated perturbation produced by an arbitrary current distribution (represented by a set of linear current sources) covered by a slotted enclosure, and the field coupled to a slotted screen due to a radiated perturbation. The effect of a given enclosure is modeled by means of a scattering matrix (which depends only on its geometry) obtained by the FEM. On the other hand, any arbitrary perturbating field can be expanded in a series of cylindrical harmonics, and then, the total field is computed everywhere using the scattering matrices. This method has the advantage over conventional FEM approaches that FEM is applied only once, and then a wide range of electromagnetic compatibility (EMC) problems can be solved with almost no extra computational effort. Two-dimensional models of relevant EMC problems involving both emission and immunity have been studied in order to extract useful information for actual 3D systems. In spite of the 2D approach, very interesting conclusions can be derived from the examples presented in this paper (like the effect of slot resonances in the field distribution within slotted enclosures or the coupling between two connected cavities).