Power transfer of transient electromagnetic fields through a plane conducting screen of finite thickness

The calculation of transient electromagnetic fields is important because of the increasing demands on system design under EMC constraints. The shielding effectiveness of a screen is characterized by the time dependence of the electromagnetic energy transfer into the shielded area caused by switched or pulsed sources. The total energy which is radiated by the transient wave can be calculated by integrating Poynting´s vector over an appropriate closed surface and over the time interval between the switching moment and infinity. In this work the power and energy balance for the electromagnetic fields excited by electromagnetic sources in the presence of a plane conducting and permeable screen are presented. Also, the results obtained by the quasi-stationary method are compared to those calculated via the full-dynamic approach.