Accession Number : AD0651650

Title :   MODEL TANK STUDY OF THE COHERENCE OF UNDERWATER ACOUSTIC SIGNALS REFLECTED FROM COMPLEX STRUCTURES.

Descriptive Note : Final rept.,

Corporate Author : UNDERWATER SYSTEMS INC SILVER SPRING MD

Personal Author(s) : Weinsteh,Marvin S. ; Aukward,Joseph A.

Report Date : 30 NOV 1966

Pagination or Media Count : 133

Abstract : The spatial coherence of wide band ultrasonic continuous noise signals reflected from and/or transmitted through plates, cylinders, spheres, and complex combinations of these structures, was determined. The measurements were made in a model water tank, in an approximately one octave band, centered at about one megahertz. The reflected signals were found to always be spatially coherent, except when the reflecting structure gave rise to more than one independent reflection. The coherence of the transmitted signal was severely degraded under a number of conditions. (Author)

Descriptors :   (*UNDERWATER SOUND SIGNALS, COHERENT RADIATION), ULTRASONIC RADIATION, REFLECTION, MODEL TESTS, SOUND TRANSMISSION, METAL PLATES, CYLINDRICAL BODIES, SPHERES, MEASUREMENT, EXPERIMENTAL DATA

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE