UWB ranging error estimation and compensation method for relative navigation

Intelligent swarm based on unmanned aerial vehicles or robots has become a research hotspot. To achieve collaborative control of dense cluster, the key information is to achieve the precise relative distance among adjacent agent clusters. Ultra-wideband (UWB) wireless transmission technology can transmit information and realize centimeter-level theoretical ranging accuracy. It has broad application prospect in coordinated navigation and control of clusters. In this paper, the UWB ranging scheme for centimeter-level ranging requirement of relative navigation is first described. Then, the reason and characteristics of the ranging error caused by the clock offset of UWB antenna in the actual environment, the relative speed between the nodes and the non-line-of-sight environment is analyzed. The state detection, error compensation and estimation methods of UWB distance measurement are studied. Finally, based on the DW1000 ultra-wideband module, the experimental environment is constructed and the method studied in the paper is evaluated. Experimental results show that the error estimation and elimination method can significantly improve the accuracy of UWB in practical application. Compared with the traditional ranging algorithm, the ranging accuracy of the proposed method is improved under the relatively static scenario and a scene with relative speed between nodes. To be specific, the error is reduced by 70% in the line-of-sight environment state and by 50% in the non-line-of-sight environment state. © 2019, Science Press. All right reserved.