Time reversal compared to inverse filtering

Inverse filtering is the compensation of the magnitude and phase distortion caused by a linear time invariant system. Recently, time reversal is proposed as a new technique suitable for UWB systems. In this paper, the theory of electromagnetic time reversal is compared to the process of inverse filter design. From a signal processing point of view, time reversal is equivalent to a phase equalizer. Time reversal can compensate for the phase distortion in UWB, but at the same time it doubles the magnitude distortion. This fact is illustrated experimentally.