ECE Seminar - Speaker: Dr. Julien Bonnel, Associate Scientist, Woods Hole Oceanographic Institution
Topic: Underwater Acoustics with A Single Hydrophone: Propagation, Physics-Based Processing, and Oceanographic Applications
Speaker: Dr. Julien Bonnel, Associate Scientist, Woods Hole Oceanographic Institution
Abstract:
Inferring information from underwater sounds requires robust experimental and numerical methods that account for a complex ocean environment, highly variable in time and space, and only partially known. Further, when considering low-frequency (f<500 Hz) sound propagation in coastal water (water depth D<200 m), the environment acts as a dispersive waveguide: the acoustic field is described by a set of modes that propagate with frequency-dependent speeds. In this context, to extract relevant information from acoustic recording, one needs to understand the propagation and to use physics-based processing. In this presentation, we will review shallow-water acoustics and modal propagation in an ocean waveguide, as well as time-frequency (TF) analysis. We will then show how modal propagation and TF analysis can be combined into a non-linear signal processing method dedicated to extract modal information from a single hydrophone, and how such information can be used to localize sound sources and/or characterize the oceanic environment. The whole method will be illustrated on several oceanographic examples, including estimation of sediment properties on the US East coast and baleen whale localization in the Arctic.
Biography:
Julien Bonnel is an Associate Scientist with Woods Hole Oceanographic Institution (WHOI, USA) since 2017. His research interests in signal processing and ocean acoustics include time-frequency analysis, source detection/localization, environmental inversion, passive acoustic monitoring, and impact of noise pollution on marine life. Dr. Bonnel is also a faculty of the WHOI-MIT joint program, where he teaches ocean acoustics and array processing.
Dr. Bonnel received the PhD degree in signal processing from Grenoble Institut National Polytechnique, Grenoble, France, in 2010. From 2010 to 2017, he was an Assistant/Associate Professor with Ecole Nationale Superieure de Techniques Avancees de Bretagne, ENSTA Bretagne, Brest, France. Dr. Bonnel is a Fellow of the Acoustical Society of America (ASA), and an Associate Editor for the Journal of the Acoustical Society of America. He was the recipient of the 2019 A.B. Wood Medal from the Institute of Acoustics (U.K.), the 2020 R. Bruce Lindsay Award from the ASA, the 2022 Early Career award from the International Commission of Acoustics, and the 2024 Medwin Prize in Acoustical Oceanography from the ASA.
The Seminars is open to the public free of charge.
*For further information, please contact Dr. John R. Buck via email.
Science & Engineering Building (SENG), Room 212
: 285 Old Westport Road, North Dartmouth, MA / Science & Engineering Building (SENG)
John Buck
508.999.9237
jbuck@umassd.edu