Improving source localization in LOS and NLOS multipath environments for UWB signals

The presence of undetected direct path conditions in the TOA (Time of Arrival)-based indoor geolocation introduces major errors into distance measurements. In the proposed location estimation, an improved procedure is introduced in Ultra-wideband (UWB) systems in Line of Sight (LOS) and Non-Line of Sight (NLOS) multipath environments by incorporating the skewness as new statistic information of multipath channel. Weighted least square error (WLS) algorithm is used to estimate source position in this paper. Simulation results show effectiveness of the proposed algorithm, by reducing source localization error. Uncertainty region between NLOS and LOS identification is reduced in the proposed method compared to previous methods.

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