Improved selective hybrid RSS/AOA weighting schemes for NLOS localization

Due to the bias of range measurements in non-line-of-sight (NLOS) environments, location schemes performances undergo a dramatical degradation. This paper proposes a set of methods that integrate all the available heterogeneous measurements, without identifying NLOS from line-of-sight (LOS) measurements, to achieve more accurate location estimation. The proposed hybrid schemes combine Radio Signal Strength (RSS) at the three best nodes, in terms of higher RSS measurements, and an angular beam around the angle of arrival (AOA) at the serving BS to give location estimation of the mobile station (MS). The proposed schemes mitigate the NLOS effect in two steps: in the first step, the weighted sum of the intersections between the three best RSS measures weighted circles and the AOA angular beam is derived. In the second step, a weighting location method that utilizes the geometrical feature of cell layout and the three selected RSS range measurements is applied. Simulation results show that the proposed methods can achieve better accuracy compared to the conventional schemes in [1].