New Technique Speeds Underwater Data Transmission
A technique called acoustic time reversal may permit faster underwater communication and data transfer by exploiting the way acoustic signals are clouded by echoes traveling at different speeds, according to researchers at the Scripps Institution of Oceanography in La Jolla, California, USA, and the NATO Undersea Research Centre in La Spezia, Italy. By playing garbled acoustic messages backwards, the sound that took the longest to travel is sent first, the second-slowest next, and the fastest last—allowing all three to arrive at the same time, converging in time and reconstructing the original signal. Researchers say they have used the technique to transmit 15 kilobytes per second at a range of four kilometers; five kilobytes per second at 20 kilometers; and have managed to transmit 100 bytes per second over 3,500 kilometers—a distance comparable to that reached by whale song. Read more
Learn more about underwater data transmissions in IEEE Xplore®
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