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Updated: May 8, 2026
08:42
Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
Published on: September 3, 2021
Measuring the effect of ambient noise directionality and split-beam processing on the convergence of the
Stephanie E Fried1, Shane C Walker, William S Hodgkiss
1Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0238, USA. eowyn@mit.edu
The Journal of the Acoustical Society of America
|August 24, 2013
Summary
Noise correlation using ambient ocean noise reveals acoustic travel times between sensors. This study examines how array size, shape, duration, and noise directionality impact correlation accuracy in underwater acoustics.
Area of Science:
- Oceanography
- Acoustics
- Signal Processing
Background:
- Ambient noise measurements provide insights into the ocean's acoustic properties.
- Cross-correlation of ambient noise can estimate acoustic travel times between sensor pairs.
- Several factors can influence the accuracy and convergence of noise correlation results.
Purpose of the Study:
- To present results from a 2010 ambient noise experiment using two horizontally separated sensor arrays.
- To investigate the impact of array geometry, duration, and noise field directionality on noise correlation convergence.
Main Methods:
- Utilized experimental data from the 2010 ambient noise experiment.
- Employed two horizontally separated arrays of sensors.
- Analyzed the correlation of ambient noise recorded by the sensor arrays.
Main Results:
- Examined the convergence of noise correlation based on experimental data.
- Assessed the influence of array size and shape on correlation results.
- Investigated the effect of data length and noise directionality on correlation convergence.
Conclusions:
- The study provides experimental evidence on factors affecting ambient noise correlation in the ocean.
- Understanding these factors is crucial for accurate acoustic path travel time estimation.
- Results contribute to the advancement of passive acoustic monitoring techniques.
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