A fast and accurate intermediate level modelling approach for electromagnetic compatibility analysis of enclosures

Intermediate level circuit models are a very fast and frequently accurate way of modelling the electromagnetic coupling in a range of electromagnetic compatibility (EMC) problems involving shielded enclosures. Typical models run in a few seconds on a personal computer, compared to many hours, or even days, required for full-wave simulations of the same problem. At the same time the accuracy obtained can be comparable, or even superior to full-wave techniques. The intermediate level models achieve this efficiency by utilising the known structure of the fields inside the enclosure and only modelling the dominant coupling mechanisms for a particular problem. While the origins of the intermediate level circuit model technique lie in the established waveguide circuit theory our current work is attempting to extend the method towards something that approaches a general analysis tool for relatively complex structures.