Tracking of an underwater sound source in range, depth and bearing in shallow Pacific water

We present matched-field inversion and tracking results for data collected in a Pacific shallow water environment. The data were collected with a vertical line array (VLA) as part of the Pacific Shelf Sea Trial in a co-operative trial by Defence Research Establishment Pacific (DREP), Victoria, BC and Applied Research Laboratory (ARL), University of Texas at Austin. The primary objective of this Trial was to evaluate matched-field processing (MFP) techniques in a Pacific shallow water environment. The data analysed here was collected while a continuous wave (CW) source was towed downslope towards the VLA. The MFP can be used to localize such sources by exploiting knowledge of the environment. This is accomplished by matching the measured data with an acoustic field prediction based on a model of the environment. The best match will indicate the most likely source position. Alternatively, if the source position is known, the best match for a selection of environmental models would indicate the most likely environment. This process, otherwise referred to as matched-field inversion (MFI), can determine the environmental parameters. These inversions are particularly effective when the position of the source and geometric configuration of the receiving array are well known. In this paper, parameters describing the mean geometric configuration of the VLA during the time of the experiment were found by using MFI