Novel technique and algorithm of signal interrogation in multi-channel FIBER BRAGG sensing system

To improve the capability and detection precision of the Fiber Bragg sensing system, the novel interrogation technique and detection algorithm based on the tunable ring laser and multiplexing technology are proposed for the multi-channel Fiber Bragg grating sensing system, which can realize the real-time monitoring of 32 channels more than 1,000 FBG sensors. Here, we use the comb filter as multi-wavelength reference instead of the traditional reference grating array. Moreover, a fast wavelength detection algorithm based on the half-power point is proposed. Compared to the Gaussian fitting algorithm, the interrogation method can be greatly improved in the precision, flexibility and working reliability.