Electromagnetic coupling through perforated shields due to near field radiators

The electromagnetic coupling through an infinite conducting sheet perforated with a finite field of holes excited by a metal radiator placed in its near field is investigated. The coupling is analyzed numerically by method of moments (MoM) with emphasis on understanding the effect of the interactions between the field of holes and the metal radiator placed in its proximity. The radiation leakage through the field of holes is found to be significant due to the proximity to the antenna, even if the holes are electrically small. Numerical results confirm that classical theory underestimates the electromagnetic coupling through small apertures by antennas placed in their near field.