High Frequency Acoustics and Signal Processing for Weapons

: Task 1: The long-term goal of this task is to determine, for a broad range of frequencies (nominally 10-100 kHz), the limitations imposed by the oceanic environment on the exploitation of coherent signal structure. This understanding is required in order to optimize sonar signal processing structures (e.g. channel conditioning, especially in shallow water), for wideband signal and processor design, and for acoustic propagation modeling. Task 2: The long-term goal of this task is to develop the capability to predict the dynamic and spatial characteristics, and the corresponding acoustic response (attenuation, local sound speed, and backscattering strength), of the bubbly wakes of Navy warships. We seek a predictive capability for how acoustic propagation and scattering vary with frequency, source-receiver geometry relative to the wake, and the shape and speed of the vessel, as well as the spatial and temporal statistics of attenuation and scattering strength in the wake.