Analysis of Towed Array Reverberation Data from 160 to 4000 Hz During Rapid Response 97
Abstract
This report describes reverberation measurements made during the NATO MILOC Rapid Environmental Assessment exercise Rapid Response 97 August-September 1997. SUS charges were used as sources and data were received on two arrays towed by RJV Alliance: the 256-hydrophone Prakla array and the 32-hydrophone mid-frequency array. The arrays were towed on five-leg tracks at three locations: a deep water site in the lonian Sea and two sites in Kyparissiakos Gulf a small intermediate-depth basin off the west coast of Greece. Reverberation data from the five arrays were analyzed in frequency bands from 160 Hz to 4000 Hz. Polar plots of the reverberation give a map of the prominent bottom-scattering features and provide a snapshot of the directional ambient noise field. Reverberation calculations were made using the Generic Sonar Model. A manual inversion procedure was used to estimate bottom loss and bottom backscattering. The model-data differences were used to produce scattering maps of the area. The polar plots and scattering maps indicated a number of scattering features not on the charts and identified a significant error in the charted position of an underwater escarpment to the south of Kyparissiakos Gulf. Follow-on swath mapping in two areas confirmed the results. The results illustrate the use of directional reverberation measurements as a useful remote sensing tool for providing a rapid map of an unknown area and directing higher-resolution measurements in potentially interesting areas. The bottom loss and backscattering can be used in sonar models to provide improved performance predictions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2000
- Accession Number
- ADA389980
Entities
People
- Dale D. Ellis
- J. Sellschopp
- John R. Preston
- R. Hollett
Organizations
- SACLANT ASW Research Centre