Estimation of Electric and Magnetic Shielding Effectiveness of a Metallic Enclosure with Apertures

This work is performed to investigate the effects of apertures on the electric and magnetic shielding effectiveness of a rectangular metallic enclosure with apertures by using an analytical formulation and experimental study. Both electric and magnetic shielding effectiveness were calculated as a function of frequency, enclosure dimensions, aperture dimensions, position within the enclosure and various aperture positions by employing a transmission line equivalent circuit approach. Different aspects are investigated such as the influence of size, position, shape and number of apertures in the calculation of shielding effectiveness. Generally, the analytical results compare well with the measurements results for electric and magnetic shielding effectiveness which were conducted in a gigahertz transverse electromagnetic (GTEM) cell for frequencies in the range 10 MHz to 1 GHz