Leveraging Distributed Acoustic Sensing for monitoring vessels using submarine fiber-optic cables

[william]

Highlights​

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  We developed a migration-based source location method to locate vessels on Distributed Acoustic Sensing data.
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  The algorithm was applied on two DAS datasets acquired from seabed infrastructure.
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  The method showed excellent performance with DAS-derived locations validated by GPS, both for the considered deep- and shallow water case.

Conclusions​

We successfully applied a processing method to automatically detect and locate vessel-induced acoustic events using two DAS datasets from two types of pre-existing seabed infrastructure, each with different field conditions. The location method consists of a migration-based source location approach and subsequent k-means clustering, and results show a clear correlation between DAS derived vessel locations with the locations from independently reported AIS data.

The method makes effective use of the high spatial-temporal density of DAS data through constructive summation of coherent waveforms over space and time. The track, speed and course of the considered vessels could be derived from the analyzed DAS data in the vicinity of the fiber-optic cable and showed consistent agreement with the AIS data. This demonstrates the potential of using DAS measurements to monitor acoustic sources, such as from vessels, in the vicinity of seabed infrastructure. Finally, the method allows for first optimizing the velocity model and then inverting for the acoustic source location in a sequential manner. This highlights the complimentary value of the method for subsurface studies.

So, everything in our on the ocean can be monitored and tracked using the vast arrays of fiber optic cables on the seabed now!

https://www.sciencedirect.com/science/article/pii/S0141118725000100

 

[william]

US, EU navies turning 750,000 miles of seafloor cables into submarine-hunting sonars​

Originally designed for communications, these cables are now adapted to act as giant, passive sonar arrays. Undersea fiber-optic cables, which stretch over 1.2 million kilometers (750,000 miles) across the ocean floor, are being used in a new way for anti-submarine warfare. A developing technology called Distributed Acoustic Sensing (DAS) is making this possible.

Over the past few years, multiple studies have confirmed that DAS can detect and track ships and submarines in shallow and deep-water environments, matching acoustic readings to vessel GPS or AIS data using artificial intelligence.

The Navy and research partners in the United States have progressed from experimental trials off the West Coast to integrating DAS data into operational networks.

The US is testing the fusion of DAS feeds with data from P-8A Poseidon maritime patrol aircraft and undersea drones, exploring how AI can enhance detection capabilities across the Pacific.

Analysts say DAS offers several advantages: it uses existing infrastructure, provides persistent and covert coverage, and scales easily over massive oceanic distances.

US, EU navies to use 750,000-mile cable network to track submarines

Undersea fiber-optic cables, which stretch over 750,000 miles across the ocean floor, are being used in a new way for anti-submarine warfare.

interestingengineering.com