A practical approach towards a timely seafloor interaction database.

Abstract

A seafloor database of physics-based parameters may be considered an ideal resource. However, geoacoustic inversion to a model accurately describing the sediment structure, sub-bottom inhomogeneities, interface roughness, and anisotropy is still a very challenging research topic. While such geoacoustic inversion challenges are resolved, a more practical approach toward the generation of a timely seafloor interaction database is sorely needed. This practical approach must offer the flexibility to accommodate any physics-based and empirical model, direct measurement, and geoacoustic inversion from all research and operational sonars. It must also offer consistency with other seafloor-related databases, sufficiency to be useful to any sonar model, and completeness to model sonar systems across a wide frequency range. Empirical seafloor scattering models have a limited number of parameters to fit all measurements across grazing angle and frequency, while the most complete physics-based models have too many parameters for high-confidence geoacoustic inversion. Therefore, a more practical worldwide seafloor database must also offer enough flexibility to accurately reconstruct the seafloor reflection and scattering functions with a minimum number of parameters. Finally, this approach must quickly arrive at an unambiguous unique solution. Such an approach will be described and demonstrated. [This effort was supported by SPAWAR.]