Target Localization in Depth and Range from Passive Sonar of Uncertain Orientation using the Elevation Angles Only

This paper presents a method to localize with a passive array an acoustic source emitting high Sound-to-Noise Ratio (SNR) Continuous Waves (CW). The method consists in measuring the elevation angle of the multiple paths between the source and the receiver and to estimate the source location by comparing, with the Hausdorff distance, the measured elevation angles with angles simulated for a sampling of the source possible positions. The procedure is tested on the real acoustic signals collected by DGA Naval Systems during the experimental deepwater 2018 ALMA campaign. During this campaign, both the source and the passive array were hung below a boat so that the orientation of the array was uncertain and varying with time. The localization technique had then to be modified to take into account the movement of the array.