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Simultaneous localization of multiple broadband non-impulsive acoustic sources in an ocean waveguide using the array
Zheng Gong1, Purnima Ratilal2, Nicholas C Makris1
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Journal of the Acoustical Society of America
|December 3, 2015
Summary
A new method generalizes array invariant techniques to pinpoint multiple underwater noise sources using temporal pulse compression. This approach accurately estimates source range and bearing, even for non-impulsive sounds in ocean waveguides.
Area of Science:
- Ocean acoustics
- Signal processing
- Array processing
Background:
- The array invariant method is established for single impulsive source localization in stratified ocean waveguides.
- Existing methods struggle with localizing multiple, non-impulsive broadband noise sources simultaneously.
Purpose of the Study:
- To generalize the array invariant method for localizing multiple uncorrelated broadband noise sources.
- To introduce temporal pulse compression and Radon transform-like image processing for enhanced source localization.
Main Methods:
- Estimating range and bearing from beam-time migration lines of modal arrivals.
- Utilizing differences in modal group velocity and polar angle for localization.
- Applying the generalized array invariant approach to towed horizontal receiver array data.
Main Results:
- Successful localization of a vertical source array and vocalizing humpback whales over wide areas.
- Achieved root-mean-squared errors of approximately 12% for controlled sources compared to GPS data.
- Demonstrated less than 10% discrepancy for humpback whale localization compared to independent triangulation.
Conclusions:
- The generalized array invariant method effectively localizes multiple broadband sources, including biological and artificial ones.
- The technique shows high accuracy in complex underwater environments.
- This advancement offers improved capabilities for underwater acoustic source monitoring and research.
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