Time-Reversal Communication in Deep Ocean: Result of Second At-Sea Experiment

Abstract

We have researched long horizontal time-reversal (phase-conjugate) communication through simulations and have proposed a method of combining the effect of time reversal and the processing of an adaptive equalizer for realizing communication with a sparse time-reversal array and communication with a moving target. In the first at-sea experiment, only passive time-reversal experiments were performed. In this second experiment, both trials of active and passive time-reversal communications were executed. As results, it is confirmed that it is possible to achieve bi-directional communication by active and passive time reversals, and that time reversal is superior to conventional methods. It is also proved that at least ten source-receivers for the time-reversal array can achieve time-reversal communication and that the performance of time-reversal communication is hardly affected by the depth of the time-reversal array.