Investigating shielded enclosures with double-layers walls

In this paper the use of double-layers walls for shielded enclosures is proposed to increase the shielding effectiveness of them. The effect of distance between two layers and the offset between two apertures in the shielding effectiveness is investigated. The usefulness of inserting a box between two layers around apertures is also presented. To analyze enclosures with double-layers wall, the eigenvector expansion and the Bethe's approximation have been used.