2019_programme: DETECTION LOCALIZATION AND CLASSIFICATION OF MULTIPLE MECHANIZED OCEAN VESSELS AND MARINE MAMMAL SPECIES OVER CONTINENTAL-SHELF SCALE REGIONS WITH PASSIVE OCEAN ACOUSTIC WAVEGUIDE REMOTE SENSING

• Session: 03. Acoustic Monitoring of Ocean Environments and Processes: Biology, Ecology, Geophysics and Man-made activities
  Organiser(s): Ratilal Purnima, Miksis-Olds Jennifer
• Lecture: DETECTION LOCALIZATION AND CLASSIFICATION OF MULTIPLE MECHANIZED OCEAN VESSELS AND MARINE MAMMAL SPECIES OVER CONTINENTAL-SHELF SCALE REGIONS WITH PASSIVE OCEAN ACOUSTIC WAVEGUIDE REMOTE SENSING
  Paper ID: 994
  Author(s): Ratilal Purnima, Zhu Chenyang, Garcia Heriberto, Kaplan Anna, Schinault Matthew, Haandegard Nils Olav, Godo Olav Rune, Makris Nicholas, Huang Wei
  Presenter: Ratilal Makris Purnima
  Presentation type: oral
  Abstract: Multiple mechanized ocean vessels, including both surface ships and\nsubmerged vehicles, can be simultaneously monitored over instantaneous\ncontinental-shelf scale regions > 10,000 km 2 via passive ocean\nacoustic waveguide remote sensing. A large-aperture densely-sampled\ncoherent hydrophone array system is employed in the Norwegian Sea in\nSpring 2014 to provide directional sensing in 360 degree horizontal\nazimuth and to significantly enhance the signal-to-noise ratio (SNR)\nof ship-radiated underwater sound, which improves ship detection\nranges by roughly two orders of magnitude over that of a single\nhydrophone. Here, 30 mechanized ocean vessels spanning ranges from\nnearby to over 150 km from the coherent hydrophone array, are\ndetected, localized and classified. The vessels are comprised of 20\nidentified commercial ships and 10 unidentified vehicles present in 8\nh/day of Passive Ocean Acoustic Waveguide Remote Sensing (POAWRS)\nobservation for two days. The underwater sounds from each of these\nocean vessels received by the coherent hydrophone array are dominated\nby narrowband signals that are either constant frequency tonals or\nhave frequencies that waver or oscillate slightly in time. The\nestimated bearing-time trajectory of a sequence of detections obtained\nfrom coherent beamforming are employed to determine the horizontal\nlocation of each vessel using the Moving Array Triangulation (MAT)\ntechnique. For commercial ships present in the region, the estimated\nhorizontal positions obtained from passive acoustic sensing are\nverified by Global Positioning System (GPS) measurements of the ship\nlocations found in a historical Automatic Identification System (AIS)\ndatabase. We provide time-frequency characterizations of the\nunderwater sounds radiated from the commercial ships and the\nunidentified vessels. The time-frequency features along with the\nbearing-time trajectory of the detected signals are applied to\nsimultaneously track and distinguish these vessels.\n
• Corresponding author: Prof Ratilal Makris Purnima
  Affiliation: Northeastern University
  Country: United States
  e-mail: