Acoustic Source Localization System Based on Channel-Merged Fiber Optics Acoustic Sensing Array

Fiber optics acoustic sensing has garnered significant attention due to its distinct advantages. This paper proposes a channel-merged fiber optics acoustic sensing array structure based on Sagnac interferometer and the corresponding single-channel spatial filtering algorithm. The proposed structure simplifies the system and data processing, enabling accurate estimation of the direction-of-arrival for broadband acoustic signals. The simulation and experiment demonstrate the effectiveness and accuracy of the novel structure and algorithm. The single-channel spatial filtering algorithm exhibits better localization accuracy and robustness than broadband fixed beamforming in simulation. Furthermore, the experiment indicates that the novel structure and algorithm achieve accurate direction-of-arrival estimation of broadband signals in the range of 2 kHz to 12 kHz with a root mean square error of 0.6<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{\circ }$</tex-math></inline-formula> and real-time localization of moving acoustic source.