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Explosion localization via infrasound
The Journal of the Acoustical Society of America
|November 10, 2009
Summary
A new meta-array technique significantly improves infrasound source localization precision. This method enhances accuracy compared to traditional back azimuth methods, offering an order of magnitude improvement in performance.
Area of Science:
- Acoustics
- Geophysics
- Signal Processing
Background:
- Infrasonic data analysis is crucial for monitoring natural and anthropogenic events.
- Traditional acoustic source localization relies on ensembles of small arrays and back azimuth calculations.
- Existing methods face challenges in achieving high precision for low-frequency sources.
Purpose of the Study:
- To compare the performance of a novel meta-array technique against a standard back azimuth approach for infrasonic source localization.
- To evaluate the precision improvements offered by the meta-array method.
Main Methods:
- Applied two acoustic source localization techniques to infrasonic data.
- Compared a standard ensemble of small arrays method with a novel meta-array approach.
- Validated techniques through numerical simulations and a field experiment using a 3-km-aperture meta-array.
Main Results:
- The meta-array technique demonstrated superior localization precision compared to the standard method.
- Improvements in precision were observed across the vicinity of the meta-array.
- Precision gains were often an order of magnitude greater with the meta-array approach.
Conclusions:
- The meta-array technique offers a significant advancement in infrasonic source localization.
- This novel approach provides enhanced precision, particularly valuable for low-frequency acoustic monitoring.
- The findings support the adoption of meta-array configurations for improved geophysical and acoustic sensing.
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