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Generation and Coherent Control of Pulsed Quantum Frequency Combs
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Phase-coherent communications without explicit phase tracking.

H C Song1, W S Hodgkiss, P A van Walree

  • 1Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0238, USA.

The Journal of the Acoustical Society of America
|September 7, 2010
PubMed
Summary
This summary is machine-generated.

This study introduces a novel time reversal communication method that eliminates the need for explicit phase tracking after initial training. This approach simplifies underwater acoustic communication systems by adapting to changing channels using previously detected symbols.

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Area of Science:

  • Underwater Acoustic Communications
  • Signal Processing
  • Wireless Communication

Background:

  • Phase-coherent communication systems rely on accurate phase tracking to compensate for channel variations.
  • Doppler shifts caused by motion can disrupt phase coherence, necessitating complex tracking algorithms.

Purpose of the Study:

  • To propose and demonstrate a time reversal communication technique that obviates the need for explicit phase tracking.
  • To simplify receiver complexity in time-varying underwater acoustic channels.

Main Methods:

  • Implemented a block-by-block time reversal communication scheme.
  • Utilized smaller block sizes and adaptive channel estimation on a symbol-by-symbol basis.
  • Leveraged previously detected symbols for channel estimation and phase compensation.

Main Results:

  • Successfully demonstrated a time reversal approach without explicit phase tracking.
  • Experimental data in shallow water (12-20 kHz) validated the proposed method.
  • The technique effectively accommodates time-varying channels.

Conclusions:

  • Explicit phase tracking can be avoided in time reversal communications under specific conditions.
  • The proposed adaptive symbol-by-symbol estimation simplifies underwater acoustic communication receivers.
  • This method offers a more robust and efficient solution for phase-coherent underwater communication.