A fast method for estimating shielding effectiveness of an enclosure with apertures

A new and fast method to determine the shielding effectiveness (SE) of an enclosure with aperture is proposed. This method is based on the Z-parameter analysis combined with a circuit theory to define which configuration of the apertures can result in the optimum SE. The method is based on the fact that an aperture with the least destruction in the current flow due the incident field will have most effective canceling field. To show the effectiveness of the method and its excellent capability in estimating SE two examples, which have been numerically investigated in recent literatures, are solved. The simulation results of this fast and simple technique fit very well with those of the complex and time consuming numerical approaches. Furthermore, using this method the designer is able to recognize the problematic points and easily can optimize the shielding geometry.