The Fbg Sensor Demodulation System Based On Ffp - Tf

Compared with other sensors, high resolution, high precision digital opticalFiber grating sensor (FBG) application is convenient, easy to constitute thedistributed control, the Bridges, tunnels, coal mines, stress of surrounding rock,roof, etc. Healthy structure detection has considerable application prospect.Wavelength coding signal demodulation of fiber Bragg grating is the key to therealization of fiber Bragg grating sensing applications. Currently, the FBGsensing demodulation method and apparatus includes: non-equilibrium M-Zinterferometer method, edge filter method, matching FBG filter method andFFP-TF (optical fiber F-P tunable filter) method, etc. Among them, the FFP-TFmethod through micro displacement actuator tuning of F-P cavity lengthscanning sensing FBG, has the advantages of high sensitivity, wide tuning range,more suitable for the multipoint scanning.FBG demodulation system is introduced in this paper the core device is thehigh resolution, high precision digital tunable F-P filter, the system based ontunable F-P filter precision degree is high, the advantages of wide tuning range,designed and developed a FBG demodulation system. The system uses STM32as main control chip, through D/A conversion module generated saw wavedriving voltage, tunable filter is used to drive the optical fiber F-P, A/D samplingmodule is used to light sensor signals of distributed FBG sensor analog dataacquisition, and the signal amplification, filtering and transmission, through PCfor data analysis and processing, get the corresponding change is measured.This article main research content is as follows:1. From the theory and method on the measurement principle of distributedFBG sensor is analyzed, studied the key technology of distributed FBGwavelength demodulation technology and its implementation methods, inparticular, we design a FFP-TF demodulation system;2. Completed the related interface circuit in the photovoltaic system design,to realize the whole of the FBG sensor demodulation system connection,debugging and testing; 3. The successful development of FBG sensor demodulation system basedon STM32. Distributed FBG sensing system using the Lab Windows softwaredesign and debugging, data collection, display, processing, query, modificationand curve drawing, etc.