Performance Evaluation of UWB Active-Passive Two-Way Ranging Distance Estimation Matrix Weighting Methods

This paper explores least squares (LS), median (MED), inverse distance weighting (IDW), distance weighted estimator (DWE) and three different weighted least squares (WLS) methods for Ultra-Wideband (UWB) active-passive two-way ranging (AP-TWR) measurement matrix estimation. The proposed methods were tested with practical experiments in line-of-sight (LOS) and two different non-line-ofsight (NLOS) conditions, and were benchmarked against an active-only single-sided two-way ranging (SS-TWR) method. The results show that the proposed methods MED, IDW and DWE achieve comparable standard deviation values, while outperforming the root-mean-squared-error (RMSE) of SS-TWR ranging by up to 14.3% in LOS and 19.08% in NLOS conditions. The experiments validate that the MED, IDW and DWE methods for AP-TWR are NLOS-robust and achieve better RMSE performance than active-only SS-TWR ranging.