Research on DAS probing performance evaluation technology and its application

Distributed Acoustic Sensing (DAS) technology, based on phase-sensitive Optical Time-Domain Reflectometry (φ-OTDR), enables real-time vibration monitoring and finds extensive applications in seismic monitoring, pipeline inspection, and security protection. However, challenges persist in DAS performance quantification, including the empirical dependence of Erbium-Doped Fiber Amplifier (EDFA) gain adjustment and signal quality degradation caused by multi-channel optical switches, which compromise detection accuracy. This paper proposes a DAS signal quality optimization framework featuring: 1) Establishment and experimental validation of quantitative metrics including signal-to-noise ratio (SNR), linearity, and flatness for performance evaluation; 2) Development of an adaptive EDFA adjustment algorithm that dynamically optimizes amplification coefficients through noise energy measurement; 3) Implementation of a multi-channel optical switch module to enhance channel expansion and multi-fiber management capabilities for large-scale distributed monitoring. Experimental results demonstrate that this approach effectively improves DAS signal quality and detection performance, providing technical support for engineering applications in complex environments.