ACOUSTIC BACKSCATTER FROM A RANDOM ROUGH WATER SURFACE.

Abstract

Acoustic backscattering from a random rough water surface has been studied experimentally to test the application of two scattering theories, a statistical description and a resonance approach. The rough surface was created by wind agitation over an anechoic tank. The wave height distribution was measured with a resistive probe and the wave slope distribution by optical glitter detection using a photocell. The distributions of backscattered sound pressures were recorded for surface roughnesses and sound frequencies corresponding to a very wide range of roughness conditions. Both statistical and resonance theories have regions of applicability and regions where they fail to predict the backscatter. Backscattering may be considered to be due to these two mechanisms, since a summation of the predictions of the two theories fits the experimental data fairly well over the complete range of angles of incidence studied. A method of analysis is suggested to relate the doppler shifted continuous wave sound spectrum to the surface wave spectrum. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1967
Accession Number
AD0825665

Entities

People

  • Ernest Charles Ball
  • John Algot Carlson

Organizations

  • Naval Postgraduate School

Tags

DTIC Thesaurus Topics

  • Backscattering
  • Continuous Waves
  • Diffraction
  • Experimental Data
  • Frequency
  • Resonance
  • Roughness
  • Scattering
  • Sound Pressure
  • Spectra
  • Surface Roughness
  • Surface Waves
  • Waves

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering