High-Frequency Interrogator for FPI-Based Fiber Sensors

Abstract— The operation of a interrogator fiber sensors based on a Fabry–Perot interferometer (FPI) with a frame update rate of up to 70 kHz is presented. The high performance is achieved due to the combination of a passive optical scheme based on a multichannel arrayed waveguide grating (AWG) and a phase algorithm for data processing. The possibility of high-frequency interrogation of the sensor with an accuracy of \({\sim}1\%\) of the measurement range 1% (50 pm) is experimentally demonstrated.