Electromagnetic Time Reversal : What does it Imply?

The main goal of this paper is to explain the definition of the term Time-Reversal in Electrical engineering in general, and in electromagnetics for wireless communications to be specific. First, the goal will be to illustrate its claimed capabilities. Some problems with the application of time reversal in electromagnetics will be discussed both theoretically and practically. All of the time reversal papers talk about reciprocal networks, so the fact of the non-reciprocity of a single-antenna system in time domain (the way we generally interpret it) proves from a theoretical point of view that there is a problem with how we interpret time reversal in electromagnetics. Finally, experimental result is shown where time reversal is used in a wireless system. The exact capabilities of time reversal in electrical engineering are exposed.