Numerical time reversal of waves

A numerical time reversal of waves is proposed instead of the conventional time reversal of wave procedure used in underwater acoustics. In the numerical method, the test sound source and the receiving arrays are used, as in the conventional method, but the transmission of the received signals after their time reversal into the same medium, as well as the measurement of the field obtained in this way at the point of the test source, is replaced by computations. To use the proposed technique for obtaining the same results as those provided by the conventional time reversal of waves, the teset source should be placed at different depths. A simplified numerical algorithm with the test source operating at a single depth is proposed and justified. This version of the time reversal of waves is successfully applied to the experiment in the Barents Sea. In contrast to the conventional method, the proposed technique allows one to study the stability of the sea medium with currents.