Transient Electromagnetic Field Interference through Circular Apertures in a Plane Screen.

摘要

The transfer of an incident transient electromagnetic field disturbance across a set of apertures in a perfectly conducting plane screen is investigated. The time-domain field integral representations are used to express the electric and the magnetic field in the screened region in terms of the tangential electric field in the screened region in terms of the tangential electric field distribution in the aperture. The latter is approximated by its value carried by the incident disturbance (modified Kirchoff approximation). Time-domain expressions are presented for a normally incident plane-wave disturbance. Since in the Kirchoff approximation the transferred field for a collection of apertures is the summation of the contributions for the individual apertures, the result yields an easy-to-use estimate for the screening efficiency of a perforated plate.