Design aspects for HIRF protection of a rectangular metallic cavity using energy selective diode grids

Metallic enclosures effectively reduce electromagnetic interference in high intensity radiated field (HIRF) environments. However, any aperture - e.g. for wireless communication with the outside - will degrade the shielding. In this paper, apertures covered with diode grids are investigated for energy selective field protection. If properly designed, such apertures will effectively block the HIRF environment from the outside while allowing low power wireless communication coming from the inside when HIRFs disappear. Here, both the density of the diode grids and the number of protected apertures are studied with regard to their effects on the shielding of a 0.5 m × 0.5 m × 0.5 m rectangular metallic cavity. The shielding efficiency is evaluated by comparing the maximum transient peaks of incident and received fields. The varying result patterns provide guidelines for a proper diode grid design in practice.