Single Mode Excitation, Attenuation and Backscatter in Shallow Water
Abstract
Executive Summary: It is well known that in shallow water the ocean bottom exerts a strong influence on acoustic propagation. Two important effects of the bottom influence are attenuation due to bottom interaction and backscatter generated by reflections from the water/sediment interface. For the active sonar application both of these factors are important and affect the design of the active sonar system. In this report the use of a vertical array of sources weighted so as to excite only one mode was considered. It was demonstrated, via simulation, that a vertical array of sources driven in an appropriate frequency band can be used to minimize the combined effects of attenuation and bottom-generated backscatter in shallow water. Several bottom types along with summer and winter sound speed profiles were considered. The results indicate that an optimum frequency band providing both minimum attenuation and minimum bottom-generated backscatter exists, and that the optimum frequency band is dependent oil the bottom type. The results of this study indicate that a vertical source array should provide improvements for active signal detection in shallow water. An experimental system should be built and demonstrated in a variety of shallow-water areas.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1995
- Accession Number
- AD1114942
Entities
People
- D. F. Gingras
Organizations
- SACLANT ASW Research Centre