Improving the speed of acoustic propagation modeling, for sonar training applications, with a 3D Gaussian ray bundling model

Abstract

This research improves the calculation speed of acoustic propagation modeling, for sonar training applications in littoral environments, by implementing a 3D Gaussian ray bundling model in the geodetic coordinates of the environmental databases. Tactical decision aids currently transform the three-dimensional environment into two dimensional radials, then compute acoustic propagation as a function of range and depth. This allows them to analyze millions of range, depth, and bearings for potential targets locations in a few minutes. But, it assumes that the cost of transformation is small compared to the speed benefit of computing propagation in Cartesian coordinates. This assumption is violated in applications where the geometry of the sensors and targets is rapidly evolving, results are strongly dependent on location, and answers must be produced faster than real time. Instead of relying on advancements in computer hardware, this research focuses on the development of a new algorithm to compute bistatic, broadband, transmission loss, and reverberation for 100 active sonar acoustic contacts on commodity laptop hardware, at rates ten times faster than the speed of sound, with no measurable impact on accuracy. [Work supported by the High Fidelity Active Sonar Training (HiFAST) Project at the U.S. Office of Naval Research.]