A study on fish acoustic response characteristics of Distributed Acoustic Sensing

Distributed Acoustic Sensing (DAS) based on backscattered Rayleigh scattering in optical fibers is a rapidly developing technology in recent years. It utilizes the backscattered light from Rayleigh scattering in optical fibers for sensing purposes. By demodulating the phase information of the backscattered light, it enables highly sensitive distributed detection of external vibrations. DAS can provide real-time monitoring of small vibration signals near the optical fiber, showcasing extensive applications in the field of marine fishery monitoring. However, there is currently a lack of theoretical knowledge regarding the acoustic response characteristics of DAS to fish sounds. In order to provide theoretical guidance for future cable laying and fish sound monitoring work, this study considers the marine environment as an isotropic homogeneous medium. It investigates the acoustic response characteristics of the DAS system under different fish sounds and cable deployment methods in the marine environment. The feasibility of using a distributed optical fiber acoustic sensing system to monitor fish vocalizations is theoretically demonstrated, further promoting diversification in passive monitoring approaches for marine fisheries.