2023_programme: Real-time underwater acoustic events detection, bearing estimation, and classification with passive ocean acoustic waveguide remote sensing

• Session: 12. Real-time underwater acoustic sensing and imaging systems: Advances- capabilities and results
  Organiser(s): Purnima Ratilal-Makris and Alessandra Tesei
• Lecture: Real-time underwater acoustic events detection, bearing estimation, and classification with passive ocean acoustic waveguide remote sensing [invited]
  Paper ID: 1889
  Author(s): Mohebbi-Kalkhoran Hamed, Schinault Matthew, Makris Nicholas, Ratilal Purnima
  Presenter: Schinault Matthew
  Abstract: Acquiring, analyzing, and monitoring underwater acoustic events in real-time is crucial for making quick decisions and aiding scientific discoveries at sea. This task requires properly optimized hardware resources and software algorithms, especially when data is acquired with a 160-element coherent hydrophone array, each sampled at 100 kHz, where the array data has to be beamformed and analyzed in 147 distinct bearings simultaneously. Here, we implemented algorithms to run on GPU, which enabled considerable speed up compared to run on CPU, such as more than 338x faster beamforming. For real-time data connection and storage between computers, we used effective high-speed network switches and storage components. We applied and adapted efficient fast algorithms widely used in image processing, including morphological image processing for power spectrogram analysis to detect acoustic events and non-maximum suppression for bearing estimation. During sea trial of the Northeastern University (NU) inhouse designed and fabricated 160-element coherent hydrophone array hardware at the U.S. Northeast coast on board the research vessel (RV) Endeavor in September 2021, we utilized the developed and optimized software, as well as high-performance computing hardware, specifically configured and assembled inhouse, to store, process and analyze data sampled at 100 kHz per hydrophone element in order to monitor acoustic events in real time. We monitored a wide range of underwater acoustic events in real-time, including marine mammal vocalizations such as Fin whale 20 Hz pulses, Humpback whale songs, Minke whale buzz sequences, as well Sperm whale and Dolphin high frequency echolocation clicks up to 50 kHz; fish-generated sounds, ship tonal and broadband signals. Furthermore, with the higher array data sampling frequency, we were able to estimate hydrophone positions along the array more accurately using own-ship echo-sounder pulses important for accurate beamforming, especially at higher frequencies.
• Corresponding author: Dr Hamed Mohebbi Kalkhoran
  Affiliation: Massachusetts Institute of Technology
  Country: United States
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