IEC 61757-3-2:2022规定了分布式光纤声传感和振动测量系统中使用的询问单元的术语、特性性能参数、相关测试和计算方法，以及特定的测试设备。本文件仅涉及通过相位敏感相干光时域反射法（OTDR）进行瑞利背散射和相位检测的方法。本文件不包括准静态和低频操作模式。IEC 61757中定义了光纤传感器的通用规范。

IEC 61757-3-2:2022 specifies the terminology, characteristic performance parameters, related test and calculation methods, as well as specific test equipment for interrogation units used in distributed fibre optic acoustic sensing and vibration measurement systems. This document refers to the Rayleigh backscatter and phase detection method by phase-sensitive coherent optical time-domain reflectometry (？-OTDR) only. Quasi-static and low frequency operation modes are not covered by this document. Generic specifications for fibre optic sensors are defined in IEC 61757.