2023_programme: Self-Noise Assessment of a Towed Array SONAR

• Session: 12. Real-time underwater acoustic sensing and imaging systems: Advances- capabilities and results
  Organiser(s): Purnima Ratilal-Makris and Alessandra Tesei
• Lecture: Self-Noise Assessment of a Towed Array SONAR [invited]
  Paper ID: 1979
  Author(s): Schinault Matthew, Radermacher Max, Ratilal Purnima
  Presenter: Schinault Matthew
  Abstract: Towed array SONAR systems give enhanced Signal to Noise Ratio (SNR) over a single hydrophone by providing array gain, directional sensing and the ability to survey wide areas. Towed systems must compensate for vibration noise and Turbulent Boundary Layer (TBL) noise within the mechanical design of the array system as it is the dominant self-noise source. While mitigation measures are taken during the design process, it is often warranted to perform risk reduction testing of a new array design under several tow conditions. A large aperture coherent hydrophone towed array system comprising of 160 elements and an aperture length of 192 meters has been developed for real-time instantaneous wide-area ocean acoustic remote sensing and monitoring. This array has seen its first sea trial off the Northeast U.S. coast. Here, a coherence and a k-omega analysis is applied to sea trial data to determine flow noise. In this analysis, we can isolate spatially correlated and uncorrelated noise sources to quantify them and provide mitigation measures or design changes. During array design a turbulent boundary layer model for flow noise estimation and environmental noise level determined the gains and cutoff frequencies necessary for performance. Using our comprehensive performance model, we compare with a parameter estimation from seatrial data to quantify array performance.
• Corresponding author: Mr Matthew Schinault
  Affiliation: Northeastern University
  Country: United States
  e-mail: