Shielding effectiveness of rectangular metallic enclosures with apertures

The determination of the shielding effectiveness of a rectangular enclosure with rectangular apertures by using analytical formulation and measurements are presented in this paper. The present analytical formulation has been extended to include modes higher than TE₁₀. Measurements conducted in a Gigahertz transverse electromagnetic (GTEM) cell show good agreement with theoretical values. The works show that the shielding effectiveness is dependent on frequency, orientation of apertures, aperture dimensions, enclosure dimensions and positions within the enclosure. Our approximate solution is computationally very efficient but may be improved further to include points nearer to the aperture.