Amplitude Modulation of an Acoustic Wave Propagating Near the Ocean Surface.

Abstract

Sixty kHz CW sound was propagated parallel to and near the ocean surface adjacent to an array of four thermistors, a salinometer, a sound velocimeter, a turbulent velocity probe, and a wave-height probe in order to investigate the statistics and environmental causes of amplitude modulation. The temporal variations of the sound amplitude were studied during four twenty-minute runs over a range of 2 meters at varying depths from near the surface to 14 meters during sea-state one conditions in water of 16 meters-depth. Analysis indicated mean percentage amplitude modulation of approximately 5% with a variance of approximately 10-3. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1971
Accession Number
AD0741108

Entities

People

  • Wilton Jeremain Smith Jr

Organizations

  • Naval Postgraduate School

Tags

DTIC Thesaurus Topics

  • Acoustic Waves
  • Amplitude
  • Amplitude Modulation
  • Modulation
  • Salinometers
  • Statistics
  • Thermistors
  • Velocimeters
  • Waves

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Oceanography.