Frequency and angle spreading for scattering from a rough ocean bottom

An analysis has been performed of the sound scattered from a Gaussian random rough ocean bottom when radiated from a time-harmonic point source and received by an omnidirectional receiver positioned at the same deep depth. Both source and receiver are moving, at low Mach number, in a plane parallel to the ocean’s surface, with arbitrary independent velocities. The problem is idealized and analyzed as a linear system with stochastically varying components, viz., the propagation distances because of the reflections from the random rough bottom. An expression is developed for the power spectral density of the received signal as a function of the source amplitude function. This expression describes the dependence of the frequency shift of the received signal upon the source and receiver speeds and upon the azimuthal angles, grazing angles, and ranges from source to arbitrary scattering facet of the rough bottom to receiver. [Work supported by ONR/AEAS Program.]