Estimate of the shielding effectiveness of an electrically large enclosure made with pierced metallic plate in a well-stirred reverberation chamber

In this document, a simple and efficacious method to estimate the shielding effectiveness of an electrically large enclosure (SEe) made with pierced metallic plate is shown under uniform and isotropic field conditions, which are produced in a reverberation chamber (RC) where the field is well stirred. The estimate is made by the calculation of the transmission cross sections (TCSs) of the walls of an enclosure and absorption cross sections (ACSs) of the inner losses. TCSs and ACSs are connected to the shielding effectiveness (SE) of the walls and inner losses, respectively; the latter are also connected to the reflectivity of the enclosure internal walls. The comparison with measurements made in an RC matches enough. It shows that the method shown here is sound. Moreover, the results support a recent model that connects SEe to SE by the reflectivity of the enclosure internal walls, and show still further that unloaded electrically large enclosures with distributed apertures are not very efficacious.