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A Stable Phantom Material for Optical and Acoustic Imaging
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Covert underwater acoustic communications.

Jun Ling1, Hao He, Jian Li

  • 1Department of Electrical and Computer Engineering, University of Florida, Gainesville, Florida 32611, USA.

The Journal of the Acoustical Society of America
|November 30, 2010
PubMed
Summary
This summary is machine-generated.

This study introduces a covert underwater acoustic communication system using direct-sequence spread-spectrum (DSSS) to enhance security. It focuses on designing waveforms for reliable low probability of interception (LPI) in challenging underwater environments.

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Area of Science:

  • Underwater Acoustic Communications
  • Signal Processing
  • Information Security

Background:

  • Covert communication systems aim for low probability of detection (LPD) or interception (LPI).
  • Underwater acoustic (UWA) channels present unique challenges, including time-varying conditions and frequency selectivity.
  • Direct-sequence spread-spectrum (DSSS) is crucial for achieving processing gain in LPD systems.

Purpose of the Study:

  • To investigate a covert UWA communication system employing DSSS and a coherent RAKE receiver.
  • To design a spreading waveform optimized for UWA channel characteristics and superior LPI.
  • To evaluate the proposed techniques using simulated and experimental UWA data.

Main Methods:

  • Utilized direct-sequence spread-spectrum (DSSS) technique.
  • Employed a coherent RAKE receiver for signal processing.
  • Developed and tested novel spreading waveforms tailored for UWA environments.
  • Validated methods with simulated data and SPACE'08 in-water experimental data.

Main Results:

  • Demonstrated the feasibility of covert UWA communication using DSSS.
  • Showcased a spreading waveform design that balances UWA channel adaptation and LPI.
  • Achieved successful communication in challenging underwater acoustic conditions.

Conclusions:

  • The proposed DSSS-based system offers a viable solution for secure covert communications in UWA environments.
  • Waveform design is critical for overcoming UWA channel impairments and ensuring low probability of interception.
  • The study provides valuable insights for future secure UWA communication system development.