A Framework for Calibrating NLOS Error To Support LBS in Urban Environments

This paper proposes a new wireless-signal map-matching method for calibrating non-line-of-sight error in urban environments. As compared with the conventional map-matching methods that utilize a continuously-tracked sigle user trajectory, the proposed map-matching method utilizes bulks of different user locations for comparison with ideal map information. By appying the proposed method to the sampled network measurements, non-line-of-sight error correction maps on distorted position domain are generated. Once the non-line-of-sight error correction maps are constructed, they can be applied to the same type of measurements thereafter. Since the proposed wireless-signal map-matching method can be installed either inside or outside the core network structure and applicable to any type of network measurements such as time-of-arrival, time-difference-of-arrival, and angle-of-arrival, it bears good implementation flexibility. A simulation result assuming a typical dense urban environment demonstrates benefits of the proposed wireless-signal map-matching method.