Wideband Shield Door With a Magnetic Absorber

It is necessary to secure a high shielding performance in a wide frequency range for a shield room to defend electrical equipment from high-power electromagnetic (HPEM) threat environments. We proposed a novel shield door with gaskets and magnetic absorbers. The magnetic losses of the magnetic absorbers realize the large shield effectiveness without impairing the door operability. The structures of magnetic absorbers are investigated through finite-difference time-domain (FDTD) analysis and experiments. We found that the multi-layered magnetic absorbers increase the shield effectiveness by 15 dB over a wide frequency range. Therefore, it is found that using the magnetic absorbers, high shielding performance can be achieved without impairing the door operability, which can provide an effective protection from the HPEM environments.