Design And Implementation Of Control Module In Optical Fiber Sensing System

Distributed fibre optic sensing(DFOS)can carry on the monitor to various industrial and civilian infrastructures real-timely.It shows good application value for the monitoring of large-scale facilities with complex structures,large space sizes,random locations of hidden dangers,and harsh detection environments.In the actual application of optical fiber sensors,corresponding control modules are needed to realize real-time monitoring of the sensing system and interactive control of various devices.The thesis uses STM32 single-chip microcomputer as the main controller,and combines Web R&D technology with embedded technology to design and implement a fiber optic sensor system control module that integrates hardware control,system detection,and data processing.The module has the characteristics of low maintenance cost and reasonable and clear UI interface layout,which improves the ease of use of the optical fiber sensing system and brings a better user experience to users.The main work and results of the thesis are as follows:1.The control module of the DFOS system is designed and implemented.This article divides the control module into an embedded part and an upper computer part for development and design.Among them,the embedded part realizes the drive of the hardware device and data collection.The upper computer part adopts the B/S architecture,the server is responsible for data processing and data communication,and the browser is responsible for presenting the data transmitted by the server to the user.Experiments show that the control module designed in this paper can meet the needs of distributed optical fiber sensing systems.2.The control of EDFA working mode and temperature is realized.Combine embedded technology with PID algorithm to realize the control of EDFA working mode and the detection and regulation of pump3.temperature,so that users can understand the working status of the sensing system in real time,and improve the ease of use and reliability of the system.4.The microwave local oscillator module with adjustable output parameters is realized.In order to facilitate accurate measurement of the Brillouin frequency shift and increase the application breadth of the control module,the STM32 is combined with the phase-locked loop ADF5355 to realize a microwave local oscillator source with adjustable start and stop frequency,sweep interval,and sweep step length Module.5.The edge detection algorithm based on wavelet transform is applied to ?-OTDR noise processing to improve the system signal-to-noise ratio.In terms of the issue of low SNR arised from noise during the experiment,an edge detection signal processing algorithm based on wavelet transform is designed.The Matlab simulation are given to verify the practicability of the algorithm,and the algorithm is further verified by the built optical fiber sensing system.The signal-to-noise ratio of the algorithm system designed in this paper is significantly improved.