Differential Frequency Hopping (DFH) Modulation for Underwater Acoustic Communications and Networking

Abstract

The primary technical objective of this effort is to realize theoretical DFH performance in the doubly spread underwater acoustic channel. To do so, we need to develop demodulation schemes that are robust to various aspects of the environment. Variations in water depth, bottom type, sound speed profile, and source/receiver location call provide for wide ranges of multi-path interference (resulting in time spread). Different wind and surface wave conditions in combination with platform motion can result in varying degrees of Doppler spreading. The developed algorithms must work well across the range of conditions that will be encountered in real-life scenarios. Within the doubly-spread underwater acoustic channel, we wish to increase throughput without penalty to the inherent interference and collision tolerant properties of the waveform. This includes channel access by multiple users sharing the same frequency band (and even the same hop set) and the same time interval.

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Document Details

Document Type
Technical Report
Publication Date
Apr 19, 2010
Accession Number
ADA518717

Entities

People

  • Dianne E. Egnor
  • Geoffrey S. Edelson

Tags

Communities of Interest

  • Autonomy
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Channels
  • Acoustic Communications
  • Algorithms
  • Autonomous Underwater Vehicles
  • Coding
  • Data Sets
  • Decoding
  • Demodulation
  • Frequency
  • Frequency Agility
  • Intervals
  • Modulation
  • Multiple Access
  • Teamwork
  • Underwater Acoustic Communications
  • Unmanned Underwater Vehicles
  • Waveforms

Readers

  • Acoustical Oceanography.
  • Radio communications and signal processing.