An Implementation and Optimization Method of RTLS Based on UWB for Underground Mine

To obtain the specific location information of personnel in the underground mine, this paper describes a real-time locating system (RTLS) based on ultra-wideband (UWB) technology. The system consists of wearable active tags, main and sub anchors, servers, and clients. Firstly, alternative double-sided two-way ranging (ADS-TWR) combined with digital filter and linear fitting is used to pre-process the noise and bias of the ranging results, obtaining the anchor-tag distance with an error less than 10cm. In order to resolve the problem of position outliers caused by random factors in the mine, the position of the moving target is estimated by the extended Kalman filter (EKF) initially. Then the mean filter (MF) will perform a secondary optimization of the results. Experimental results show that the positioning accuracy of the system reaches 0.06m in the line-of-sight environment. The positioning accuracy is improved effectively and the system shows a strong anti-noise performance.