NLOS error mitigation method for UWB ranging in dense multi-path environments

To mitigate the NLOS (non-line-of-sight) error of UWB (ultra-wideband) ranging caused by obstructions in dense multi-path environments, an effective NLOS error mitigation method is proposed in this paper. The principles and characteristics of NLOS error are considered, and based on the path loss model of UWB signal, through comparing the energy of paths arriving at different time, the NLOS error estimation is formulated, which is further used to calibrate the original ranging result. A less computational and low complex path detection algorithm is proposed to implement the method. Measured data is used to test the proposed method, and the results show that the ranging precision can be improved significantly.