Understanding RF Shielded Enclosures

Radio frequency shielding is an approach to avoid undesired energy being coupled into equipment under test. The ability of an enclosure to avoid undesired RF fields to couple to the device under test is known as its Shielding Effectiveness (SE) Emerging sensitive wireless devices operate with minimum power levels and require a shielding level of more than 100dB for wireless testing.

In this study a new approach to increase the SE of enclosures to more than 100dB is demonstrated.The enclosure can be considered as a wave-guide with only single mode of propagation (TE10). In this paper,the effect and advantages of double-wall on Shielding Effectiveness of RF enclosures are proposed. The effect of considering a gap “d” between walls of enclosure and an offset on apertures are investigated. An enclosure with aluminum walls is modeled and simulated using finite element method in High Frequency Structural Simulator (HFSS, Ansoft).