Characterization of non-Rayleigh Acoustic Scattering by Elongated Scatterers in the Water Column and on Boundaries

The echo statistics associated with a randomly oriented prolate spheroid randomly located in the sonar beam are modeled. The cases of a smooth and rough spheroid, both in the water column (i.e., case in which boundaries are not involved), and on a boundary are investigated. The modeling begins with the analytical physics-based expression for the scattering amplitude of a smooth prolate spheroid. The following properties are then incorporated which leads to a random echo: randomly rough outer boundary of spheroid, random orientation, and random location in the sonar beam. The contributions of each property to the echo statistics are studied both separately and collectively. Graduate student Saurav Bhatia was funded principally to conduct this research as part of his graduate research. Kyungmin Baik, a WHOI post-doctoral fellow, also participated in the research.