Real-time phase demodulation and data administration of distributed optical fiber vibration sensing system

Distributed optical fiber sensing system (DOFS) has great potential in areas of petroleum exploration and ocean defense. By algorithm optimization in different coding environment, the multi-point and real-time heterodyne demodulation of DOFS is achieved. In experiments, the length of the optical fiber is 500m, the spatial resolution is 5m and the system sampling rate is 200kHz, under which condition the data rate reaches up to 160MB/s and the system can stilled be demodulated timely. Based on this, by plotting the three-dimensional diagram (vibration intensity versus time and space), the whole DOFS can be detected continuously and accurately.