光栅定位是大规模超弱光纤光栅阵列制备及铺设质量检测的关键技术之一。针对传统光时域反射仪定位超弱光栅时存在的问题，提出了一种超弱光栅阵列的相位-强度二维定位方法。该方法采用光栅时域反射技术查询阵列中的单体光栅，通过调节选择脉冲和入射脉冲之间的相位差，捕捉反射信号的光强峰值，实现对目标光栅的准确定位。构建了超弱光栅阵列的定位系统，对1009个平均反射率-34 dB、间隔2.5 m 的超弱光栅阵列进行了定位实验，定位误差小于10 cm。

The location of fiber Bragg grating (FBG) is one of the key technologies for the fabrication and the laying quality of the large ultra-weak FBG array. Aiming at solving the problems existing in the traditional optical time domain reflector for locating ultra-weak FBGs, a two-dimension location method based on phase and intensity is proposed. The method interrogates the single FBG with optical time domain techniques, and locates the target FBG by adjusting the phase difference between the input pulses and the selection pulses and detecting the peak power of reflective signal. The system for the FBG array is constructed to locate the 1009-FBG array with the average reflectivity of -34 dB and the spatial space of 2.5 m, and the 0.1 m position error is obtained.