Accession Number : AD0786011

Title :   An Experimental Study of the Reflection of Underwater Sound from the Sea Surface.

Descriptive Note : Technical memo.,

Corporate Author : SACLANT ASW RESEARCH CENTRE LA SPEZIA (ITALY)

Personal Author(s) : Wijmans,Willem

Report Date : 15 AUG 1974

Pagination or Media Count : 59

Abstract : An experimental study of forward scattering of sound from a rough sea surface has been made using an explosive charge as a broadband sound source and a linear array of omnidirectional hydrophones as a receiver. Using the surface-grazing angle of the incident sound and the sea-surface roughness as parameters the signal coherence has been examined for a single hydrophone (temporal coherence) and for the signals from two hydrophones of the array (spatial coherence). A simple theory has been used to guide the analysis. The surface scattering is assumed to consist of a coherent part and an additional incoherent part such that the total average received power is conserved. This time-frequency theory describes the surface-scattering process sufficiently well to agree with the experimental results. (Author)

Descriptors :   *Underwater sound, *Ocean surface, Underwater sound signals, Reflection, Scattering, Roughness, Explosive charges, Broadband, Hydrophones, Coherence, Theorems, Italy

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

Distribution Statement : APPROVED FOR PUBLIC RELEASE