The Research Of Distributed Fiber Bragg Grating Temperature Monitoring Data Processing System

With the rapid development of industrial construction in recent years, health monitoring of large structures is paid more and more attention. Distributed sensor network can conduct a comprehensive and systemic monitoring to production equipment. Fiber Bragg grating sensor is based on wavelength encoding, easy to reuse and form sense network, and it has the advantages of corrosion resistance, anti electromagnetic interference and so on. It is talent showing itself in many different kinds of sensors, Sensing network formed by the optical fiber grating sensor has a broad application prospect in the field of bridge structure monitoring, oil and mine safety monitoring, the granary temperature monitoring and so on.Firstly, the paper mainly discusses the sense and demodulation technologies of FBG, describes the coupled mode theory and the temperature sensing principle of FBG, and expounds the multiplexing and demodulation technology which is commonly used by fiber grating sensing network.Secondly, the paper builds the distributed FBG sensor demodulation system by using high precision grating demodulator, introduces the working principle of each part of the fiber grating demodulation and the grating multiplexing technology used by sensing network.Then, the paper designs the application of distributed sensing and monitoring network, focus on writing the software of upper computer. The users can real-time online monitor the change of external parameters, save the parameters information, analysis the data of parameters. From requirements analysis to system function design, the paper briefly introduces the programming language and SQL Server database, describes the function of each part of the software realization process.Finally, the paper mainly carries on the running test of distributed temperature monitoring data processing system, the relationship between temperature and wavelength is calibrated by using PC software, analysis temperature sensitivity of FBG on experiment and summary the factors affecting the temperature characteristics of fiber grating.