Ocean Acoustic Time-reversal Mirror
نویسندگان
چکیده
Two ocean acoustics experiments demonstrating the implementation of a time reversal mirror have been conducted. Pulsed sound (50-ms with center frequency 445 Hz) was refocused to the position of a probe source out to ranges as great as 30 km in 125-m deep water. In addition, a technique to refocus at ranges other than that of the probe source also was demonstrated. These results are summarized along with examples illustrating the temporal stability of the focused eld. Finally, theoretical considerations are discussed for a time reversal mirror operating at an order of magnitude higher frequency.
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