The Brillouin Scattering Distributed Fiber Optic Sensing System For The Study Of High-speed Digital Boxcar

This dissertation is focus on the temperature sensitive mechanism of the Brillouin-scattering signal and on the basis of domestic techniques,the methods and approaches of signal detection and processing in distributed Brillouin fiber-optical sensor system.A digital multi-point average method (Digital BOXCAR) has been proposed based on the characteristics and the sorts of fiber-optical sensors and by analysis the feature of the Brillouin-scattering signal,and also comparisons of all sorts of Weak-Signal Detection theory. On the basis of the research of former graduates,we design the Hardware & Software of Digital BOXCAR by employing the High-speed AD FPGA chip and the USB protocol controller chip,,And we realized the High-speed Sampling,Digital Adding,High-speed Storage,Data Transmission and interface circuits of PC successfully.The principles of system design and key points of the realization process of the blue print are discussed. We also show the new technology details of the system design and all the problems which ones may encounter and the effective solving methods. By testing and adjusting the system again and again,we have the basic functions such as Adding,Storage,Transmission of the Data of Digital BOXCAR,and the basic sampling signal testing. The results proved the feasibility of the scheme of the system design.Finally,the problems and the difficulties of experimental system and some opinions on the future development of the system is given.