Mobile Location Estimator in Mixed LOS/NLOS Conditions Using UKF Banks

In wireless mobile location systems, NLOS problem has been considered as the key issue that affects the estimation accuracy. In this paper, mobile location in a mixed line-of-sight/non-line-of-sight (LOS/NLOS) condition is considered, and a NLOS error mitigation technique is proposed, which utilizes unscented Kalman filter (UKF) to jointly estimate mobile state and the hidden sight state based on the data collected by each BS. In addition, data fusion method is further applied to achieve high estimation accuracy. Simulation results demonstrate that the performance of the proposed method meet the requirement of the FCC E911 in different LOS/NLOS conditions.