Spatial Correlation of Detections for Impulsive Echo Ranging Sonar

mpulsive Echo Ranging systems are air-deployed, active, multistatic sonar systems designed to operate in both littoral and open-ocean areas. Sources ensonify a target, and multiple receivers detect resulting short-duration echo signals. Because the source illuminates ocean bottom features, particularly in shallow littoral waters, and the ocean is rich in independently generated transients, the system requires automation dedicated to reducing operator load and enhancing target recognition. The APL-designed Multiple Return Association and Localization (MRAL) algorithm serves as part of this automation. MRAL is an efficient data-fusion algorithm that groups sets of spatially consistent energy detections, collected across pings and receivers, into single operator alerts. Operator classification decisions based on grouped detections are less frequent and more informed than those otherwise made for each detection independently. Also, combined detections provide the means for automation to harness the joint information inherent in the individual detections. (