Digital Coding for underwater Acoustic Multipath Channels.

Abstract

Low data rate, multipath propagation, input energy constraints and other considerations make it difficult to transfer conventional radio communications practice to long range (one to five megameter) underwater acoustic multipath channel telemetry. The energy channel capacity CJ in bits/joule, for any waveform channel with well-defined capacity C bits/sec at signal power S watts, is defined as C/S bits/joule. It is shown that for several coherent channels, the supremum of CJ over S is approached as S approaches zero. This implies that the communication system that obtains high channel rate in bits/joule operates at low received signal-to-noise power ratio, S/N. High signal-to-noise energy ratio E/NO and good error performance is achieved by using long codewords. A binary symmetric channel and a waveform distorting channel with Gaussian noise of known power spectral density are considered.

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1984
Accession Number
ADA157170

Entities

People

  • H. Kwon

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Channel Capacity
  • Communication Systems
  • Data Rate
  • Gaussian Noise
  • Multipath Channels
  • Multipath Transmission
  • Noise
  • Radio Communications
  • Telemetry
  • Waveforms

Fields of Study

  • Engineering
  • Physics

Readers

  • Radio communications and signal processing.