Underwater source localization using a fleet of three gliders

The NATO Centre for Maritime Research and Experimentation has been exploring the potentials of passive acoustic payload equipped underwater gliders for maritime intelligence, surveillance and reconnaissance missions. During the CMRE Glider Sensors and Payloads for Tactical Characterization of the Environment 2015 sea trial, it was successfully demonstrated that a fleet of three passive acoustic payload equipped gliders simultaneously detected the ‘anomalous’ sound in shallow water and reported back to the glider control center. This work studies the feasibility of localizing the source (the coordinates and the depth) using the information provided by the glider fleet. The results of three different source localization approaches are compared. The impact of the errors in conventional glider time and location data, as well as insufficient/incorrect knowledge of the ocean environment on underwater source localization is discussed. (Work funded by NATO-Allied Command Transformation.)