Utilizing a single-photon detector, a novel direct-detection optical-fiber sensor for distributed measurement of temperature based on spontaneous Brillouin scattering is proposed and demonstrated experimentally. In our scheme, the ratio of the backscattered Rayleigh signal and the backscattered Brillouin anti-Stokes is adopted to retrieve the monitored temperature information along the optical fiber. Taking advantage of the high sensitivity of the single-photon detector, our proposed system achieves a dynamic range of 20 dB without any optical amplification. The obtainable dynamic range corresponds to a sensing distance of 120 km with a measured temperature error of 0.96°C. Furthermore, the proof-of-concept experiment demonstrates 1.2 m spatial resolution over 4.2 km sensing link with 1.24°C temperature error. Considering the performance we achieved now, and the increasing improvement of the fabrication technology of sing-photon detector, the photon-counting distributed Brillouin sensor is opening a door in the field of optical-fiber sensors.

中文翻译：

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基于布里渊散射效应的单光子探测器分布式温度传感系统

利用单光子探测器，提出了一种新型的基于自发布里渊散射的分布式温度直接测量光纤传感器，并进行了实验验证。在我们的方案中，采用反向散射的瑞利信号与反向散射的布里渊反斯托克斯的比率来沿光纤检索监测到的温度信息。利用单光子检测器的高灵敏度，我们提出的系统无需任何光学放大即可实现20 dB的动态范围。可获得的动态范围对应于120 km的感应距离，测得的温度误差为0.96°C。此外，概念验证实验还证明了在4.2 km的感测链路上1.2 m的空间分辨率和1.24°C的温度误差。