2025_programme: Detection of the Kauai Beacon signal by Ocean Networks Canada’s NEPTUNE observatory



  • Day: June 19, Thursday
      Location / Time: A. TERPSIHORI at 12:20-12:40
  • Last minutes changes: -
  • Session: 12. Observing the Oceans Acoustically
    Organiser(s): Bruce Howe, Kay Gemba
    Chairperson(s): Bruce Howe, Kay Gemba
  • Lecture: Detection of the Kauai Beacon signal by Ocean Networks Canada’s NEPTUNE observatory
    Paper ID: 2351
    Author(s): Lanfranco Muzi, David R. Barclay, David Hughes
    Presenter: Lanfranco Muzi
    Abstract: This study focusses on the reception of the Kauai Beacon signal on the hydrophones of the NorthEast Pacific Time-series Undersea Networked Experiments (NEPTUNE) observatory, operated by Ocean Networks Canada (ONC, a University of Victoria Initiative.)\nThe Kauai Beacon is a low-frequency source designed to support long range acoustic-propagation studies, used e.g. to produce basin-scale estimates of the variability of bulk ocean temperature and transmission loss. Located off of the north shore of the Hawaiian Island of Kauai, the beacon resumed regular transmission of its coded thermometry signal in 2023, after its first operational stint (1998 – 2006.)\nNEPTUNE is a permanent, cabled undersea observatory providing power and communication to hundreds of acoustical, oceanographic, seismic, and geophysical sensors. In its current configuration, the observatory includes 17 offshore hydrophones, distributed over five stations along its 840 km of fiber-optic cable, extending from the Vancouver Island shore across the North American and Juan de Fuca tectonic plates. All sensors stream data continually and the time series are made publicly available in quasi real time on ONC’s data portal, Oceans 3.0.\nThe NEPTUNE stations supported by the Barkley Canyon node have an unobstructed path to the Kauai Beacon. They are located at a distance of about 4100 km from the source, and are bottom mounted at depths close to the deep sound channel axis. The installations include a four-element volumetric array of Ocean Sonics icListen HF hydrophones (deployed at the “Barkley Node” site since 2021) and, since the Summer of 2024, a single icListen AF hydrophone at the “Barkley Upper Slope” site. We illustrate the techniques employed to detect the signal, highlight the results, describe the difficulties met, and elaborate on future developments, particularly with regard to improving the performance of the instrumentation in this particular task.
  • Corresponding author: Dr Lanfranco Muzi
    Affiliation: Ocean Networks Canada, University of Victoria
    Country: Canada