NICOP - High resolution multi-beam subbottom profiling as a new tool to understand mechanisms of mid frequency
Abstract
High resolution multi-beam subbottom profiling as a new tool to understand mechanisms of mid frequency reverberation and clutter Understanding the mechanisms of reverberation and clutter is a major issue to optimize active sonar performance in shallow water. Recent advanced researches carried out at the Applied Research Laboratory (ARL) Penn State University have put forward an important contribution of particular spatial scales (about 10 cm) in the low to mid frequency reverberation. However, the identification of the physical origin of these impacting scales remains uncertain. There is strong evidence that the underlying feature lies under the water-bottom interface (possibly sediment inhomogeneities or sub-bottom interface roughness or even a combination of both) but neither the exact feature nor mechanism is known yet. To advance our understanding of the reverberation mechanism, additional (local) measurements are required of the scattering parameters. This collaborative work between the French Hydrographic and Oceanographic Office (SHOM) and ARL proposes to exploit a high resolution sub-bottom profiler (SBP) to identify and quantify scattering mechanisms. In particular, the proposal is focused on the Kongsberg SBP120 multi-beam sub-bottom profiler, which operates from 2-7 kHz and is installed on the French Hydrographic and Oceanographic Vessel BEAUTEMPS-BEAUPRÉ. The main objective is to obtain quantitative measures of seabed roughness and volume heterogeneities from the SBP in 3-dimensions. Advanced qualitative imaging methods will also be explored. Our approach is organized in 4 workpackages : (1) Use/adapt an acoustic simulation model (2) Determine the information content of the SBP-120 data (3) Apply the strategy to a selected data set(s) (4) Develop/apply imaging techniques to map the sub-bottom structure. The project will result in ? a capability/methodology for estimating scattering parameters from SBP120 data ? scattering parameter estimates from at least 1 specific area ? potentially deeper understanding of the scales and mechanisms that control seabed scattering
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2017
- Source ID
- N629091712001
Entities
People
- Yann Alain Stephen
Organizations
- Office of Naval Research
- United States Navy