Xenaki Angeliki, Gerstoft Peter, Williams Ethan, Abadi Shima
Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece.
Noiselab, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0238, USA.
J Acoust Soc Am. 2025 Jul 1;158(1):801-825. doi: 10.1121/10.0037218.
Extensive monitoring of acoustic activities is important for many fields, including biology, security, oceanography, and Earth science. Distributed acoustic sensing (DAS) is an evolving technique for continuous, wide-coverage measurements of mechanical vibrations, which is suited to ocean applications. DAS illuminates an optical fiber with laser pulses and measures the backscattered wave due to small random variations in the refractive index of the material. External stimuli, such as mechanical strain due to acoustic wavefields impinging on the fiber-optic cable, modulate the backscattered wave. Continuous measurement of the backscattered signal provides a distributed sensing modality of the impinging wavefield. Considering the potential use of existing telecommunication fiber-optic cables deployed across the oceans, DAS has emerged as a promising technology for monitoring the underwater soundscape. This review presents advances in DAS in the last decade and details the underlying physics from electromagnetic to mechanical and eventually acoustic quantities. To guide the use of DAS for ocean applications, the effect of DAS acquisition parameters in signal processing is explained. Finally, DAS is demonstrated on data from the OOI Regional Cabled Array for the detection of sound sources, such as whales, ships, and earthquakes.
对声学活动进行广泛监测对包括生物学、安全、海洋学和地球科学在内的许多领域都很重要。分布式声学传感（DAS）是一种不断发展的技术，用于对机械振动进行连续、宽覆盖范围的测量，适用于海洋应用。DAS用激光脉冲照射光纤，并测量由于材料折射率的微小随机变化而产生的背向散射波。外部刺激，如声波场撞击光缆产生的机械应变，会调制背向散射波。对背向散射信号的连续测量提供了一种对入射波场的分布式传感方式。考虑到现有跨洋部署的电信光缆的潜在用途，DAS已成为一种有前途的水下声景监测技术。本文综述了过去十年中DAS的进展，并详细阐述了从电磁量到机械量最终到声学量的基础物理学原理。为指导DAS在海洋应用中的使用，解释了DAS采集参数在信号处理中的作用。最后，利用海洋观测站区域电缆阵列的数据展示了DAS用于检测声源（如鲸鱼、船只和地震）的情况。
