Prediction of clutter on the Malta Plateau.

Abstract

NURC has conducted a series of experiments on the Malta Plateau, Mediterranean Sea, with the focus on collecting environmental and acoustic clutter data. Strong correlation between the environmental and processed acoustic data has been established for certain regions which provides important information to enhance prediction capabilities and signal processing algorithms and to eventually reduce the clutter returns in the sonar processing chain. However, strong clutter-like returns are persistently observed from a confined location on the Plateau with no clear indication of significant scattering features, i.e., no evidence of bathymetric features, variations in sub-bottom stratification, or changes in bottom geoacoustic properties. Only the sub-bottom profiling shows inclusions in the upper 5 m of the sediment, and these inclusions are hypothesized to have slightly different geoacoustic properties than the surrounding. This hypothesis is presented and verified by backscattered time-series computations using a two-way prediction model applied in an environment similar to that of the acquired acoustic data. [Work supported by the NATO Undersea Research Centre, the CLUTTER JRP partners, and the Office of Naval Research OA321.]