研制了一种基于Sagnac干涉仪的分布式光纤传感器，可实时进行管道泄漏检测与定位．阐述了该传感技术的工作原理和泄漏点定位方法，并推导了泄漏引起的光信号相位变化表达式。管道泄漏实验结果表明，水压为0．3MPa时，该技术能有效地检测到管道泄漏的发生并准确定位。

A distributed optical fiber sensor based on the principle of Sagnac interferometer is developed. It is used to detect pipeline leakage and locate leakage point in real-time. The measuring principle and the leaking point location method for the technology are described. The representation of phase change caused by leakage is formulated for optic signal. An experiment is designed to verify the distributed optical fiber acoustic sensor. The results verify that the detection technology can detect pipeline leakage effectively and locate leak point accurately in the condition that the water pressure is 0.3MPa.