DIRECTIONAL PROPERTIES OF UNDER-ICE AMBIENT ACOUSTIC NOISE,

Abstract

The outputs of a pair of hydrophones suspended beneath the ice and separated sometimes vertically (210 feet) and sometimes horizontally (359 feet) were tape recorded. In order to measure directional properties of the ambient noise so recorded, the tapes were analyzed using polarity coincidence crosscorrelation. The results showed low frequency correlation as high as 34 percent and some high frequency correlation, probably resulting from marine life and strumming antenna wires in camp, as high as 6 percent. The correlation was generally stable over a period of minutes and often hours. Selected correlation functions are shown. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 28, 1963
Accession Number
AD0420335

Entities

People

  • C. R. Greene Jr.

Organizations

  • Naval Ordnance Laboratory

Tags

DTIC Thesaurus Topics

  • Ambient Noise
  • Directional
  • Doppler Effect
  • Frequency
  • Frequency Bands
  • Frequency Shift
  • Human Factors Engineering
  • Hydrophones
  • Noise
  • Polarity
  • Radio Frequency
  • Strumming

Readers

  • Acoustical Oceanography.
  • Electrical Engineering
  • Mathematics or Statistics