基于随机数编码的相位敏感光时域反射仪  

Phase-sensitive OTDR based on random number coding

作　　者：尹康 王宇 李沛峰 苏玉文 白清 刘昕 靳宝全 Yin Kang;Wang Yu;Li Peifeng;Su Yuwen;Bai Qing;Liu Xin;Jin Baoquan(Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education and Shanxi Province,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Transportation Technology Research&Development Co.,Ltd.,Taiyuan 030600,China)

机构地区：[1]太原理工大学新型传感器与智能控制教育部与山西省重点实验室,太原030024 [2]山西省交通科技研发有限公司,太原030600

出　　处：《电子测量与仪器学报》2022年第9期125-131,共7页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(62175175);山西省基础研究计划(202103021222010);山西省基础研究计划(20210302124599);山西省重点研发计划(202102130501021)项目资助。

摘　　要：相位敏感光时域反射仪(Ф-OTDR)的传感距离与空间分辨率相互制约,为进一步提升系统性能,提出了光脉冲随机数编码方法,分析了基于编码的相干探测Ф-OTDR的线性化理论,阐述了随机数编码与解码原理并推导了随机数编码的增益数学模型。实验证明,在1 kHz脉冲重复频率,与40 ns脉冲宽度的条件下,与单脉冲调制的Ф-OTDR相比,使用128 bit 40 ns脉冲宽度的随机数编码可将传感距离从25 km提升至50.26 km,且在接近尾端处还原的振动信号信噪比可达17.51 dB,能够较好还原振动信号。研究表明随机数编码方法为提升Ф-OTDR传感性能提供了有效的解决方案。The sensing distance and spatial resolution of phase-sensitive optical time domain reflectometer(Ф-OTDR) are mutually restricted. In order to further improve the system performance, a random number coding method of optical pulse is proposed in this paper. The linearization theory analysis of the coherent detection Ф-OTDR based on coding and the principle of random number encoding and decoding are described, and the gain mathematical model of random number encoding is deduced. Experimental results show that compared with the single-pulse equivalent, the sensing distance can be increased from 25 km to 50.26 km by using 128 bit random number code with 40 ns pulse width and 1 kHz pulse repetition frequency, and the signal to noise ratio can reach 17.51 dB at 50.22 km, where the vibration signal can be well restored. The research shows that the random number coding method provides an effective solution for improving the performance of Ф-OTDR.

关 键 词：光纤传感 Ф-OTDR 传感距离 随机数编码 

分 类 号：TP212.1[自动化与计算机技术—检测技术与自动化装置]