Research On Distributed Optical Fiber Temperature Measurement And Data Processing Technology Based On Raman Scattering

The applications of optical fiber from communication to optical fiber sensor are over the medical, transportation, communication, service, military, entertainment, energy, education and other fields, which have provided an effective medium for the development of the information world. The distributed optical fiber sensing technology is used to monitor the temperature of the space field,which can quickly, accurately and safely complete the measurement task.Distributed optical fiber temperature sensor is mainly carrying temperature information to the use of backward Raman scattering signal light, and through the Anti-Stokes light and Stokes light demodulation principle, on large warehouses, transportation of oil and gas resources, coal power generation plants and other fields, which plays a significant role.Firstly, the DTS distributed systems research at home and abroad, as well as the future prospects of the advantages of the temperature measurement system were generally analyzed, which developed the optical fiber based on backward Raman scattering temperature demodulation scheme and introduced the Raman scattering theory in detail, the principles of distributed optical fiber temperature measurement were specifically addressed. This paper presented a distributed optical fiber temperature measurement system design, a detailed description of hardware features of each module,and the analysis of the various parts of the system design parameters.A detailed analysis of principles and ideas of each module hardware design was presented,including the fiber distributed hardware design, high-frequency narrow pulse laser design, the design of the optical signal detection system, a low noise amplifier design, signal acquisition circuit design and data processing module design. And through the use of MATLAB to signal spectrum characteristics analysis, the Raman noise signal was filtered; the paper designed the different cumulative frequency filtering method of contrast experiments, combining with the analog filter,digital filter, and comprehensive utilization of Butterworth filter to carry the information of temperature signal filtering denoising; the paper proposed RLS algorithm, combining with IIR adaptive filter in FPGA workflow on noise signal processing; the data acquisition card function characteristics were carried out to validate the simulation with LABVIEW; the paper designed the FPGA for the cumulative filter process experimental analysis. Finally, according to the module assembly system, the paper designed the the client software of data channel connecting between the system and computer, the optical fiber temperature measurement experiment based on this has proved the correctness of the theoretical analysis.