Accession Number : AD0776242

Title :   Stability of the Acoustic Pathlength of the Ocean Deduced from the Medium Stability Experiment.

Descriptive Note : Technical memo.,

Corporate Author : JOHNS HOPKINS UNIV SILVER SPRING MD APPLIED PHYSICS LAB

Personal Author(s) : Stowe,D. W. ; Wallman,L. H. ; Follin,J. W. , Jr. ; Luke,P. J.

Report Date : JAN 1974

Pagination or Media Count : 47

Abstract : In an extensive ocean test known as the Medium Stability Experiment conducted at the Atlantic Undersea Test and Evaluation Center, rms linearly detrended fluctuations of acoustic pathlength were found to be of the order of lambda/100 at 10 kHz over a 1-minute period. Pathlength stability was deduced from precise measurements of acoustic travel time over a 2500-meter path extending from a 70-meter depth to the bottom of the ocean. A state-of-the-art inertial measurement unit was used to compensate the travel time for motion of the acoustic projector. The report details the analysis used to remove errors in motion compensation from the travel time data order to obtain a measure of the acoustic pathlength stability. (Author)

Descriptors :   *Underwater sound, Phase studies, Sound transmission, Stability, Sonar signals, Time studies

Subject Categories : Physical and Dynamic Oceanography
      Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE