Sonobuoy System and Concept of Operations for Time-Reversal-Based Target Detection

Existing multistatic airborne ASW systems require high power sources and are unable to exploit the significant forward scattering strength of a submarine target due to the blinding presence of the direct blast. Time reversal (TR) is a recent method for focusing acoustic energy at a point using pairs of source and receive arrays. The TR focus provides a measure of propagation channel stability, allowing one to determine when the medium is disrupted as would occur when a scatterer such as a submarine target passes between the two arrays. In Phase II we propose to implement a TR barrier using SSQ-125-XN1 and SSQ-77C DVLA buoys in a controlled experiment. The purpose of this experiment is to demonstrate a TR barrier under typical at-sea conditions using realistic sonobuoy hardware. Using the data from this experiment we will (1) quantify the performance of the system in terms of probability of detection and detection range, (2) develop a procedure to automate target detection in the presence of noise and environmental fluctuations, and (3) validate and improve the models developed in Phase I for predicting TR performance.