Some Properties and Effects of Reverberation in Acoustic Surveillance,

Abstract

Reverberation or clutter may be considered as a special case of an extended, randomly varying target causing an echo which is like noise in that it is approximately a Gaussian random process. In the general case, the statistical properties are not easy to interpret physically, but when the scatterer reflectivity does not vary with time, the statistical properties of the clutter are described by its scattering function which is shown to be the joint probability density function of the distribution of scatterers in delay and in doppler frequency shift. If the delay distribution of the scatterers is uniform over an interval equal to the duration of the transmitted waveform, then the clutter may be considered wide-sense stationary, at least locally, so that it is described by a power density spectrum. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1967
Accession Number
AD0780462

Entities

People

  • Harry Urkowitz

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Abstracts
  • Acoustic Surveillance
  • Diffraction
  • Doppler Effect
  • Echoes
  • Frequency
  • Frequency Shift
  • Intervals
  • Mathematics
  • Ocean Surveillance
  • Probability
  • Probability Density Functions
  • Reflectivity
  • Reverberation
  • Scattering
  • Surveillance

Readers

  • Acoustical Oceanography.
  • Approximation Theory.
  • Radio communications and signal processing.