Fault Self-Detection Technique in Fiber Bragg Grating-Based Passive Sensor Network

In this paper, we propose and experimentally investigate a fault self-detection technique in fiber Bragg grating (FBG)-based passive sensor network. Here, once a fault occurs on connecting fiber or FBG sensor, it can be detected directly by the proposed sensing network. Moreover, in the proposed FBG sensor system, the multiple wavelength-division-multiplexing FBG sensor numbers can be reduced significantly and also increase the sensing capability for sensing temperature and strain simultaneously. In the measurement, when the temperature variation is from 20 °C to 75 °C, the measured Bragg wavelength shift of tension is nearly 0.74 nm. While the strain shift of 0.3 mm is applied on FBG, the Bragg wavelength shift of nearly 1.88 nm is observed.