UACE2023: IMPROVED ACTIVE SONAR EXPERIMENT FOR MEASURING MATCHED-FILTER LOSS VS BANDWIDTH AND DURATION



  • Session: 11. Large Time-Bandwidth acoustic signals for target detection and tracking
    Organiser(s): Tesei Alessandra
  • Lecture: IMPROVED ACTIVE SONAR EXPERIMENT FOR MEASURING MATCHED-FILTER LOSS VS BANDWIDTH AND DURATION [invited]
    Paper ID: 873
    Author(s): Murphy Stefan M., Hines Paul C., Coffin Matthew E. W., Bates Jeffrey R., LePage Kevin D.
    Presenter: Murphy Stefan M.
    Presentation type: oral
    Abstract: Preliminary results are presented from a fixed-geometry experiment conducted during the Littoral Continuous Active Sonar 2018 (LCAS18) sea trial that was led by the Centre for Maritime Research and Experimentation (CMRE) in November 2018. The objective of the experiment was to measure environmental matched-filter loss as a function of bandwidth and duration independently in shallow water. A stationary source transmitted LFM waveforms with varying bandwidth and duration (up to 2048 Hz and 64 s), which were received on stationary hydrophones at ranges of approximately 100, 200, 300, 5000, 10,000, and 20,000 m (125-m water depth, 75-m source and receiver depths). The experiment was similar to one conducted during the LCAS16 trial, the main difference being that bandwidth was increased to improve the resolution of individual propagation paths, such as the surface reflection, which exhibited matched-filter loss that increased with increasing duration. This is an expected result because motion-related distortion occurs when the surface varies on a timescale shorter than the pulse duration. Furthermore, the LCAS18 experiment employed more hydrophones than LCAS16 in order to capture multiple surface grazing angles. At steeper grazing angles the effective roughness/motion of the surface is greater, so the matched-filter loss is expected to increase with increasing grazing angle.
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  • Corresponding author: Mr Murphy Stefan
    Affiliation: DRDC
    Country: Canada
    e-mail: