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Published on: June 16, 2023
Determination of acoustic waveguide invariant using ships as sources of opportunity in a shallow water marine
Christopher M A Verlinden1, J Sarkar1, B D Cornuelle1
1Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093-0238, USA cmverlin@ucsd.edu, bsarkar@ucsd.edu, bdc@ucsd.edu, wkuperman@ucsd.edu.
Abstract:
The waveguide invariant (WGI) is a property that can be used to localize acoustic radiators and extract information about the environment. Here the WGI is determined using ships as sources of opportunity, tracked using the Automatic Identification System (AIS). The relationship between range, acoustic intensity, and frequency for a ship in a known position is used to determine the WGI parameter β. These β values are interpolated and a map of β is generated. The method is demonstrated using data collected in a field experiment on a single hydrophone in a shallow water environment off the coast of Southern California.
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