FBG sensor demodulation method based on an amplified spontaneous emission light source

A new demodulation method of fiber Bragg grating (FBG) sensing signal, which is by making use of the monotonic decline section of an amplified spontaneous emission (ASE) light source, is proposed. The setup of the system is simple according to the method. It can deal with not only static measurands, but also dynamic measurands. Because there are no moving parts in it, its high-frequency response is excellent. The systems are set up to measure temperature and dynamic strain according to the proposed method. The experiments on measuring temperature and dynamic strain are carried out. Its temperature measuring range is about 300°C. One of the biggest advantages of the method is that the dynamic range and its sensitivity are adjustable through adjusting the ASE light source output power.