First Experiment Result of Time-Reversal Communication in Deep Ocean

We have researched time-reversal (phase-conjugate) acoustic technology for long horizontal communication by simulations, and have proposed a method of combining time reversal and the use of an adaptive equalizer to realize communication even with a sparse time-reversal array and the communication with a moving underwater vehicle. An experiment in a real sea was executed in Suruga-bay at a frequency of 500 Hz at a distance of 10 km, and its results are described in this paper. In the trial, the projector oonlyn the array side malfunctioned. Thus only a passive time-reversal communication experiment was performed. It was confirmed that communication could be achieved using only 10 elements of the array by the proposed method at a water depth of 1,100 m.

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