The analysis of multi-mode cylindrical enclosure shielding effectiveness with apertures

The destructive effect in electronic products is very serious in high power electromagnetic pulse by coupling into the cavity. The multi-mode shielding effectiveness of cylindrical cavity with apertures was studied in high power electromagnetic pulse in this paper by equivalent circuit and TLM (Transmission Line Method) method. The simulation results show that the electromagnetic shielding effectiveness is poorer with the nearer observation position to the aperture. The polarization direction have great effect on the shielding effectiveness and the electromagnetic shielding effectiveness is high with 0 degrees polarization direction angle before resonance frequency. The minimum electromagnetic shielding effectiveness and the high-order mode appears at the resonant frequency of the cavity therefore the resonant frequency can be obtained by electromagnetic shielding effectiveness.