Investigation on a NLOS error mitigation algorithm for TDOA mobile location

In typical Urban environment, non-Line-Sight (NLOS) propagation between the base station (BS) and mobile station (MS) became the main factor of the positioning error. As a result, the study on the mitigation of its negative influence becomes a focus. Base on Chan algorithm, this paper presents a TDOA mobile location algorithm, which can improve the positioning accuracy effectively. The positioning process includes NLOS error identification and its mitigation. First, the Wylie algorithm is used to identify the existence of NLOS. And then, the time of arrival (TOA) is update based on the difference of TOA and the distance between BS and MS. This coordinate of the MS is estimated by using Chan algorithm in the process of this distance calculating. Simulation results show that this algorithm can mitigate the NLOS error and improve the location accuracy in different environment effectually.