论文部分内容阅读
为提高测温精度和空间分辨率,搭建了基于电光调制器调制探测光脉冲的布里渊光时域反射分布式温度传感系统。分析并验证了电光调制器输出探测光脉冲信号的特性、电信号解调系统中窄带滤波器中心频率以及检波器响应速率对反射测温精度和空间分辨率的影响。结果显示,中心频率为700 MHz的窄带滤波器进行布里渊增益谱扫描时,布里渊光时域反射测温系统可获得高的测温精度;采用响应速率较快的检波器获得的系统空间分辨率较高。在此基础上,采用电光调制器调制脉宽约10ns的探测光脉冲进行测温实验,在约3km的传感距离上获得了±1.24℃的测温精度和1.217m的空间分辨率,实现了较高空间分辨率和温度精度的分布式光纤传感测量。该实验可为BOTDR温度传感解调系统中器件参数的选择提供参考。
In order to improve the temperature measurement accuracy and spatial resolution, a Brillouin optical time-domain reflection distributed temperature sensing system based on the electro-optic modulator modulation probe light pulse is proposed. The characteristics of the probe optical pulse signal output by the electro-optic modulator, the center frequency of the narrow-band filter in the demodulation system of the electro-optic modulator, and the influence of the detector response rate on the precision of the temperature measurement and the spatial resolution of the reflection are analyzed and verified. The results show that the Brillouin optical time-domain reflectometry system can achieve high temperature measurement accuracy when the narrow-band filter with a center frequency of 700 MHz is used to perform the Brillouin gain spectrum scanning. The system with a fast response detector Spatial resolution is higher. On this basis, using the electro-optic modulator to modulate the probe pulse with pulse width of about 10ns to measure the temperature, the temperature measurement accuracy of ± 1.24 ℃ and the spatial resolution of 1.217m were obtained at the sensing distance of about 3km, Distributed Fiber Optic Sensing with Higher Spatial Resolution and Temperature Accuracy. The experiment can provide reference for the choice of device parameters in BOTDR temperature sensing demodulation system.