ROFDR Optical Fiber Temperature Sensor

Temperature has always been an indispensable indicator in safety testing and is used in all aspects of life.Before the advent of optical fiber temperature sensor,people used a traditional point-measuring type of temperature sensor.Because spot detection has certain defects,it gradually can no longer meet people's requirements,thereby promoting the ROTDR(Raman optical time domain reflectometer)fiber.The advent of temperature sensors.Compared to traditional point-of-use temperature sensors,ROTDR fiber-optic temperature sensors have longer measurement distances,higher accuracy,and a wider range of applications.However,the spatial resolution and signal-to-noise ratio of this temperature sensor are mutually constrained,resulting in space for the system.The resolution is not very high and the accuracy is not enough.In order to pursue higher precision and spatial resolution,this paper conducted the ROFDR(Raman optical frequency domain reflectometry)optical fiber temperature sensor after conducting the experiment of the ROTDR optical fiber temperature sensor.,and designed a corresponding simulation experiment through in-depth exploration.The main content of the paper is as follows:1.In-depth study of the optical time domain reflectometry technology,mastered the optical time domain is actually based on the relationship between the optical propagation distance and time in the optical fiber to locate,found that the light generated Raman scattering will produce Stokes light And anti-Stokes light,through the effect of temperature on Stokes light and anti-Stokes light,established the relationship between light intensity and temperature,and obtained several methods of demodulating temperature,and compared and Analysis,select one of the temperature measurement methods for experimentation.2.A ROTDR fiber optic temperature sensor system was set up.The Stokes light and anti-Stokes light produced by Raman scattering were collected.An effective denoising method was used to denoise the acquired signal.The demodulation principle of antiStokes light is demodulated by X-ray light demodulation,and a temperature-controlled box is used to heat one of the optical fibers,and the measurement accuracy is measured as a reference temperature.3.Based on the basic principle of ROFDR optical fiber temperature sensor,deeply mastered the system structure and working method of the entire ROFDR optical fiber temperature sensor,innovatively uses the frequency of the frequency sweeping circuit for positioning,and the basis for temperature demodulation of the ROTDR fiber temperature sensor.The temperature measurement method of ROFDR system was obtained and the simulation steps were designed.4.Based on the analysis of ROFDR theory,a function similar to the light signal emitted by the system light source is designed as a simulation light signal to satisfy the system conditions,and the temperature distribution in various places in the optical fiber is set,and the corresponding demodulation is adopted.The temperature method is used for demodulation,and the accuracy of temperature measurement is measured by comparison with the initially set temperature,and compared with the ROTDR fiber temperature sensor system.