DIRECTIVITY OF RECEIVED OCEAN NOISE.

Abstract

At a point under the ocean the noise intensity received from ships and waves on the surface has a directivity pattern which could be observed by a directive receiving array. The report derives simple theoretical formulas for the mean noise intensity pattern or, equivalently, the average pattern over a long period of time. The derivations use ray propagation theory. They assume an ocean with plane surface and bottom and with propagation velocity depending on depth only. Noise sources have constant probability density over the surface. To use the formulas it is not necessary to trace rays, except to include the effect of dissipation of sound energy into heat. This dissipation, although small, has an important influence on the directivity pattern in some cases. A numerical example is included for a deep ocean that exhibits a sound channel at 666 fathoms. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 03, 1967
Accession Number
AD0653102

Entities

People

  • E. N. Gilbert

Tags

Communities of Interest

  • Air Platforms
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Deep Oceans
  • Directives
  • Dissipation
  • Intensity
  • Oceans
  • Probability

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Oceanography.
  • Phased Array Antenna Design.