A multiplexed fiber grating sensor system based on injection-locking and high-order Pound-Drever-Hall techniques is presented. In the sensor system, two distributed feedback fiber lasers and a mode…
A digital feedforward-type linewidth narrowing scheme for single tune lasers is presented in this paper. An acousto-optic frequency shifter driven by RF signal generated by a direct digital synthes…
The measurement distance is one of the most important parameters for distributed acoustic sensor (DAS). In this paper, we report a long-distance and high-sensitivity DAS system based on time-gated …