LT Christopher Verlinden, USCG
“Applications of Sources of Opportunity in Passive Ocean Acoustics”
Abstract: Recently in the field of Ocean Acoustics there has been a movement towards the use of passive, rather than active techniques for localizing acoustic sources and extracting information about the environment. Ships, which can be tracked using the Automatic Identification System (AIS) represent an underutilized acoustic source of opportunity that can potentially be used to localize sources, invert for environmental parameters, and extract information about the ocean environment such as the local time dependent Green’s Function. This talk demonstrates an application of using surface ships as a source of opportunity in source localization. Previous passive source localization methods break down due to our inability to model the acoustic environment with sufficient accuracy to create reliable replica signals; this method eliminates the need to model the waveguide by using measured, rather than modeled, replica fields. The method uses AIS ship tracking data to populate a library of replica cross-correlation vectors which are then compared to the cross-correlation of received acoustic signals on two horizontally separated hydrophones in the presence of an unknown acoustic radiator. The coordinates associated with the correlation vector from the library, which most closely corresponds to the measured correlation vector, must be the location of the unknown acoustic radiator. The theory is described, tested using simulations, and validated with data from a field experiment.
Biography: LT Chris Verlinden graduated from the Coast Guard Academy with high honors with a degree in Marine and Environmental Sciences in 2008 whereupon he was stationed aboard the Coast Guard Icebreaker Polar Sea as the Science Officer for two years. Research missions while serving aboard Polar Sea ranged from methane hydrate research to capturing polar bears. In 2010, LT Verlinden transferred to USCGC Sycamore out of Cordova, Alaska where he served as Operations Officer for two years. During this time, LT Verlinden served as task force leader for on scene Coast Guard Assets during the Deepwater Horizon Oil Spill, and as project officer for oil spill response exercises in support of Operation Arctic Shield. LT Verlinden completed his graduate work at Scripps Institution of Oceanography earning an M.S. in Oceanography in 2014 with research focusing on passive ocean acoustics. LT Verlinden currently serves as a Marine Science Instructor at the U.S. Coast Guard Academy.