Study on the multiplexed sensor system based on tunable fiber laser with fiber Bragg grating

In order to overcome the limited bandwidth and the weak power of the laser and enlarge the range of the multi-point detection effectively,a tunable fiber laser is designed and used as the source of optical sensor system with WDM and TDM technique.Based on the mode couple theory,using a stepper motor to tune the wavelength of FBG to scan the fiber laser demodulation is analyzed theoretically and studied experimentally.Strain resolution of about 2.9με/step is obtained.The system has high signal-to-noise ratio and can multiplex a large number of FBGs,which is economical and practical in sensor array system.