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Diversity combining for long-range acoustic communication in deep water
1Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0238, USA. hcsong@mpl.ucsd.edu
The Journal of the Acoustical Society of America
|August 17, 2012
Summary
This study demonstrates long-range underwater acoustic communication is possible over 550 km. Diversity combining and equalization techniques successfully decoded a signal, enabling robust deep-water data transmission.
Area of Science:
- Underwater acoustics
- Signal processing
- Telecommunications
Background:
- Coherent long-range acoustic communication in deep water presents significant challenges.
- Channel fading and noise degrade signal quality over extended distances.
Purpose of the Study:
- To demonstrate the feasibility of long-range acoustic communication in deep water.
- To show that diversity combining and sparse channel-estimate-based equalization improve signal quality and data rates.
Main Methods:
- Acoustic communication experiment over a ~550 km range in deep water.
- Utilizing a towed source at ~75 m depth and a horizontal line array at ~200 m depth.
- Applying diversity combining and sparse channel-estimate-based equalization to decode an 8 phase-shift-keying signal.
Main Results:
- Successful decoding of a 40 Hz bandwidth (230-270 Hz) communication signal at ~550 km range.
- Achieved an effective data rate of 17 bits/s.
- Demonstrated mitigation of channel fading and increased output signal-to-noise ratio through diversity combining.
Conclusions:
- Coherent long-range acoustic communication is feasible in deep water.
- Diversity combining and advanced equalization techniques are effective for robust underwater data transmission.
- This approach enables reliable communication over hundreds of kilometers.
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