Pulsed Electromagnetic Waves Between Parallel Plates: The Modal-Expansion and Generalized-Ray Approaches

The electromagnetic field propagated between two perfectly electrically conducting screens is investigated in the time domain using two approaches. In addition to a solution based on the well-known eigenfunction expansion, we provide an alternative series expansion composed of generalized-ray constituents. As the constructed closed-form space-time expressions are straightforward and easy to implement in any computational tool, they may serve for educational purposes. In particular, they may be useful for those who want to get acquainted with some basic aspects of the propagation of the pulsed electromagnetic field. Key features of both time-domain approaches are discussed, and illustrative numerical examples are given.