矿井下分布式光纤定位精度及感测距离研究

Research on Location Accuracy and Sensing Distance of Distributed Optical Fiber under Mine

煤矿井下分布式光纤定位系统通常采用双Mach-Zehnder干涉仪分布式光纤振动传感技术,针对该技术存在感测距离短、系统空间分辨率低等问题,采用两个分布反馈(DFB:Distributed Feedback)激光束和密集波分复用(DWDM:Dense Wavelength Division Multiplexing)的非对称双Mach-Zehnder干涉仪的分布式光纤振动传感技术,通过奇异值分解(SVD:Singular Value Decomposition)算法进行降噪处理,并提出基于SVD的互相关时延算法。实验证明,该算法能有效提高定位精度和感测距离,当感测距离为61 km时,定位误差为51.2 m。当矿井灾难发生时,能对被困人员精准定位,保障了有效救援时间。

The distributed optical fiber positioning system in coal mine usually adopts the dual Mach-Zehnder interferometer distributed optical fiber vibration sensing technology. The sensing distance is short and the spatial resolution of the system is not high. A distributed optical fiber vibration sensing technique for asymmetric double Mach-Zehnder interferometer is proposed. It uses two DFB （Distributed Feedback ） laser beams and DWDM （Dense Wavelength Division Multiplexing）, the noise reduction is processed by SVD （Singular Value Decomposition） algorithm, and a cross-correlation delay algorithm based on SVD is proposed. Experiments show that the localization method can effectively improve positioning accuracy and sensing distance. When the sensing distance is 61 km, the positioning error is 51.2 m. When the mine disaster happens, it can locate the trapped people accurately, and guarantee the effective rescue time.