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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
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Multi-source aliasing suppression for distributed fiber acoustic sensing with directionally coherent enhancement
Optics Letters
|October 15, 2020
Summary
Distributed fiber acoustic sensing (DAS) can now suppress overlapping signals from multiple sources. This new directionally coherent enhancement technology improves acoustic detection in noisy industrial environments.
Area of Science:
- Physics
- Engineering
- Signal Processing
Background:
- Distributed fiber acoustic sensing (DAS) is a powerful tool for detecting disturbances along optical fibers.
- A key limitation of DAS is signal superposition from multiple adjacent sources, hindering accurate analysis.
- Existing methods struggle to isolate individual signals in complex acoustic environments.
Purpose of the Study:
- To introduce and demonstrate a novel directionally coherent enhancement technology for DAS.
- To address the challenge of multi-source aliasing in acoustic sensing.
- To improve the signal extraction capabilities of DAS in noisy conditions.
Main Methods:
- Development and application of a directionally coherent enhancement technique tailored for DAS.
- Feasibility verification through preliminary studies involving submerged weak target signals and same-frequency signals from multiple sources.
- Experimental validation of signal separation and reconstruction from superimposed data.
Main Results:
- Effective extraction of weak target signals from strong broadband noise.
- Successful separate rebuilding of two different same-frequency signals from a single detected signal.
- Demonstrated suppression of multi-source aliasing in DAS through the proposed enhancement technology.
Conclusions:
- The proposed directionally coherent enhancement is the first method to suppress multi-source aliasing in DAS.
- This technology significantly enhances DAS capabilities for acoustic detection in large-scale industrial settings.
- Potential applications include discharge detection in high voltage substations and acoustic emission flaw detection in factories.
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