Shield degradation in the presence of external conductors

When an external conductor is located in close proximity to apertures in an EMI shield the amount of energy coupled through these apertures can be greatly increased. Earlier work by the authors was limited to problems where the geometry was small compared to the wavelength of interest. Using the finite difference time domain (FDTD) technique a solution can be found for much larger geometries. A variety of geometries have been analyzed and the findings are presented in this paper