Exploitation of Environmental Complexity in Shallow Water Acoustic Data Communications

Abstract

LONG-TERM GOALS. Conduct feasibility experiments and associated algorithm design to explore how complexity of the shallow water acoustic environment can be used advantageously in acoustic data communications. OBJECTIVES. Exploit environmental complexity through both real and synthetic aperture spatial processing to mitigate multipath-related fading and intersymbol interference in acoustic data communications. APPROACH. The origin of this research is our experience with carrying out ocean acoustic time reversal experiments over a broad range of frequencies. Through a series of experiments conducted jointly between MPL and the NATO Undersea Research Centre (NURC), we have demonstrated that complexity of the ocean environment fundamentally is advantageous and facilitates rather than inhibits the resolution of physical processes, detection of targets, and acoustic telemetry of data. Furthermore, the time reversal experiments have illustrated that the ocean maintains a far greater inherent coherence than previously has been thought possible. Thus, the overall goal of this research is to take advantage of the self-adaptive nature of the complex ocean environment and learn how to exploit fluctuations, scattering, and variability. Multiple-Input / Multiple-Output (MIMO) Acoustic Data Communications The active time-reversal approach directly achieves spatial diversity through use of an array of sources. Source array diversity can be complemented with receive array diversity to enable transmitting independent communication sequences in parallel thus increasing the total data rate through the channel. The source array and receive array pair implements a multiple-input/multipleoutput (MIMO) system.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2008
Accession Number
ADA603545

Entities

People

  • William Hodgkiss

Organizations

  • Scripps Institution of Oceanography

Tags

Communities of Interest

  • Sensors

DTIC Thesaurus Topics

  • Acoustic Communications
  • Algorithms
  • Autonomous Underwater Vehicles
  • Communication Channels
  • Communication Systems
  • Data Rate
  • Data Transmission
  • Decoding
  • Detectors
  • Digital Communications
  • Frequency
  • Intersymbol Interference
  • Ocean Environments
  • Oceans
  • Shallow Water
  • Underwater Acoustic Communications
  • Water

Fields of Study

  • Engineering

Readers

  • Acoustical Oceanography.
  • Radio communications and signal processing.
  • Systems Analysis and Design