Numerical simulation for the shielding effectiveness of enclosure with apertures

For the purpose of ventilation, cooling, and human-computer interaction, the apertures must be added on the enclosure. However, these apertures break the integrity of the enclosure and are considered to be the main reason for electromagnetic energy leakage, which directly influence the shielding effectiveness (SE) of the enclosure. The transmissionline matrix (TLM) method has been employed in this paper to investigate the electromagnetic shielding performance of enclosure with apertures. The effects of some related parameters of aperture such as its shape, quantity, position, depth, ratio, direction etc are analyzed over a broadband (0-2GHz) in detail. Then, the parameters of apertures which influence the SE of enclosure are proposed. The calculated results indicate that the SE can be effected significantly by the aperture´s number, aspect ratio, directions and opening rate. Finally, the design rules for apertures are put forward.