Accession Number:

ADA214435

Title:

Wind Speed Dependence of Acoustic Ambient Vertical Directional Spectra at High Frequency

Descriptive Note:

Lecture transcript

Corporate Author:

NAVAL UNDERWATER SYSTEMS CENTER WEST PALM BEACH FL

Report Date:

1989-05-26

Pagination or Media Count:

25.0

Abstract:

A measurement of the acoustic ambient arriving from a horizontal direction along with total acoustic intensity spectra allows one to infer both the total directional spectra and some physical characteristics of the sources of sea surface sound. A long-term measurement of these two quantities was made at high frequency, i.e., 8 kHz, in the Tongue of the Ocean, The Bahamas. The horizontally directed ambient was measured using vertically oriented line arrays and was observed for wind speeds ranging from 1 to 30 knots. The resulting data base was used to estimate the statistics of anisotropic noise gain relative to the isotropic noise gain. Differences in the functional dependence and residual statistics were found for two cases whitecaps present and not present. The relation of these results to the total directional spectra and a model of the near-surface distribution of acoustic sources are discussed. Keywords Underwater acoustics.

Subject Categories:

  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE