采用单工循环编码解码的分布式光纤喇曼温度传感器  

A Distributed Optical Fiber Raman Temprature Sensor with Cyclic Simplex Coding

作　　者：余向东[1] 金尚忠[1] 张在宣[1] 王剑锋[1] 张文平 

机构地区：[1]中国计量学院光电子技术研究所,杭州310018 [2]杭州欧忆光电科技有限公司,杭州310018

出　　处：《光子学报》2014年第7期52-56,共5页Acta Photonica Sinica

基　　金：国家973项目(Nos.2010CB327804)资助

摘　　要：针对连续脉冲编码解码技术在分布式光纤喇曼温度传感器应用中出现被测光纤非线性峰值阀值光功率变低、编码过程较复杂等问题,提出了一种将光脉冲码均匀分布在整条被测光纤的单工循环编码解码技术和应用方案,并在27km单模系统中与传统单脉冲技术系统做了对比实验.结果表明:相比连续编码解码技术,单工循环编码解码技术不仅保持了编码解码技术相对于传统单脉冲技术的信噪比改善能力,而且有效地提高了光纤的非线性峰值阀值光功率.在编码时只需循环发送一组码,就可使系统的信噪比和测量距离获得极大的提高.采用211位循环编码解码技术的多模系统经16万次重复测量后,可在25km处获得±1.5℃的温度不确定度,空间分辨率为3m.In order to solve the problems of lower nonlinear threshold optical peak power in fiber and more complicated coding algorithm caused by continuous pulse coding technique, a cyclic simplex coding technology and ites application system in which the coding optical pulses were evenly distributed along the whole fiber were proposed. The comparative experiment adopting 27 km multimode optical fiber between traditional single pulse system and cyclic simplex coding system were made for validating the correctness of theory. The results show that compared to the continuous pulse coding, the cyclic simplex coding not only keeps same signal-to-noise improvements to traditional single pulse technique, but also increasese nonlinear threshold optical peak power in fiber, and has more simple coding process in which it just transmits one row codes circularly, so the system can improve signal-to-noise ratio and sensing range greatly in the same amount of measurement time. With this coding technology, the system attains ±1.5℃ temperature measuring uncertainty and achieves 3 m spatial resolution on 25 km of multimode optical fiber after 160 000 measurement times.

关 键 词：光纤 传感器 喇曼散射 编码 非线性 温度传感 

分 类 号：TN253[电子电信—物理电子学] O437.3[机械工程—光学工程]