Analysis Models for Case Design Above 1 GHz

Abstract

This paper describes an analysis method used to provide enclosure (case) design guidance applicable at frequencies above 1 GHz. The models developed herein establish design constraints for EMI gaskets, fastener spacing, cover to case flatness, and case thickness. Additionally, this paper shows the usefulness of the models for evaluating existing design discrepancies uncovered bv tests. Summary This analysis approach, including models, and their application technique, was developed when a need was determined by a 200V/M R.F. Susceptibility requirement up to 40 GHz. Hardware was being designed and no method to determine a higher design confidence was available. This analysis was used to provide early design analysis of equipment enclosures for compliance with the 200V/M requirement above 1 GHz. The shielding effectiveness of cases was evaluated for leakage.