Parameter Estimation Using Multi-Frequency Range-Dependent Acoustic Data in Shallow Water
Abstract
The localization of targets and knowledge of environmental parameters is essential to both passive and active underwater sonar applications. The use of full field inversion methods or matched field processing for target localization has been shown to be effective for determination of target bearing, range and depth. The performance of these methods is strongly dependent on the accuracy of knowledge of environmental parameters. Previously the lack of this knowledge inhibited the application of these methods in shallow water. The objective of this report is to demonstrate that target localization parameters and environmental parameters can be jointly estimated. The results are based on sea trial data collected by SACLANTCEN in October 1993 in the Mediterranean. This report focuses on estimation of all unknown model parameters - geometric, geoacoustic, and ocean sound-speed - by the inversion of acoustic field observations. The inversion is based on data from a vertical array and carried out using information at multiple frequencies. Global optimization using a directed Monte Carlo (random) search based on genetic algorithms is used. Genetic algorithms are based on analogy with biological evolution, one of the most efficient optimization systems. All geometric parameters are well determined, a range-dependent geoacoustic model is determined, and the ocean sound-speed is estimated.-The use of observations at multiple frequencies provides better resolution of the estimated parameters. To date, these target localization methods have been applied to passive sonars, in the future it is expected that they will also be applied to active sonars.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1996
- Accession Number
- AD1121055
Entities
People
- D. F. Gingras
- P. Gerstofl
Organizations
- Centre for Maritime Research and Experimentation