针对铁路及城市轨道交通运行环境多变、监测距离较长且监测方法易受雷电影响等问题，提出了一种基于光栅阵列的列车定位及测速方法.该方法利用抗电磁干扰能力强、复用容量大的超弱光栅阵列构成振动传感网络，采用非平衡马赫-曾德尔干涉解调法实现对列车运行振动信号的检测，在小波降噪后通过基于短时能量分布的端点检测法来实现对列车的精确定位，并利用相邻测区之间的距离与列车抵达的时间差来推算列车在该区域的运行速度.为验证该方案的可行性，在武汉地铁7号线湖工站至野芷湖站间搭建了实验系统进行现场测试.实验结果表明，该方案能实现对列车实时位置的精确定位，且测速误差为±2 km/h，且经过长时间的测试，基于该方案的系统具有很好的可靠性和稳定性.

A train positioning and speed measuring method based on grating array was proposed to solve the monitoring problems of railway and urban rail transit, such as variable operating environment, long monitoring distance and vulnerable to lightning. The ultra-weak grating array with strong anti-electromagnetic interference ability and large multiplexing capacity is used to form vibration sensing network, and the unbalanced Mach-Zehnder interference demodulation method is used to realize the detection of train traveling vibration signal. The accurate positioning of the train is realized by the endpoint detection method based on the short-term energy after the wavelet denoising, and the running speed of the train in the area is calculated by the distance between the adjacent measuring areas and the arrival time difference of the train. An experimental system was set up between Hugong and Yezhihu stations of Wuhan Metro Line 7 for field test to verify the feasibility of this scheme. The experimental results show that this scheme can achieve accurate positioning of the real-time position of the train, with the measuring speed error is ±2 km/h. And after a long time of testing, the system based on this scheme has good reliability and stability.