Experimental demonstration of time reversed reverberation focusing in an oceanic waveguide

Abstract

The robust focusing and pulse compression provided by time reversal techniques may be exploited for active sonar. Backscattering from the rough water–bottom interface can be used as a surrogate probe source [Lingevitch et al., J. Acoust. Soc. Am. 111, 2609–2614]. This method uses a selected time-gated portion of the reverberation signals (or backscattered signals) to provide a transfer function between a time-reversing array (TRA) and a corresponding range interval on the bottom. The potential of a TRA for studying the application of shallow water bottom scattering is investigated experimentally using both sea-data collected in July 2004 in the Mediterranean sea off the Italian coast, and ultrasonic water tank data.