Backscattering by a suspension of spheres

Predictions of backscattering from a suspension of nominally spherical particles are compared with a series of experimental observations. Initially measurements were taken on single particles to establish the form function for the glass spheres employed and comparisons are made with calculations based on resonance scattering theory. The form function description of sphere scattering has been employed to describe the interaction of sound with a suspension of spheres, with first-order multiple scattering being included by accounting for the attenuation introduced by the presence of the suspension itself. The study is in part stimulated by the application of acoustic backscattering for measuring suspended sediment concentrations in the marine environment and some discussion is presented on this topic.