Acoustic backscattering at low grazing angles from the ocean bottom

Abstract

The measurement of acoustic backscattering at low grazing angles from the ocean bottom in a shallow water area near Charleston, South Carolina is described and the results of data analyses are compared with results reported earlier. It was found that, with fixed platforms resting on the bottom in shallow water at both test sites, interference in the form of backscatter from a rough sea surface is a significant problem. A modest frequency dependence and relatively strong azimuthal dependence for bottom backscattering strength were observed at both test sites. No strong relationship could be determined between bottom backscattering strength azimuthal dependence and bottom roughness characteristics.