A theoretical model for doppler spread of backscattered sound from a composite roughness sea surface

Abstract

For calculating the Doppler spread of acoustical reverberation from the sea surface, good results are achieved by applying a composite-roughness model. The small wavelets primarily responsible for the backscattering are carried by long waves with higher amplitudes 0 Small roughness results are applied to conceptual "facets" on the long waves. As coupling parameters between shortand long-wave scattering, the rms-slope, the rms-vertical and horizontal velocities of the facets and their cross-correlation coefficients are used. They are calculated from the covariance function of the sea surface as a function of the facet length. For a Pierson-Moscowitz spectrum, some computer results are given.