A UWB-based 3D location system for indoor environments

In this paper we introduce a 3D location system for indoor environments which comprises of a hierarchical location scheme and a UWB-based location network which consists of UWB sensors and tags. By using a UWB-based network, the proposed location system takes advantage of UWB characteristics such as low power transmission, multi-path fading robustness, ultra-fine time resolution and multiple simultaneous transmissions. Using the UWB characteristics and the hierarchical organization of the proposed location scheme, the location system can provide a wide geographical coverage and precise positioning. The location scheme is based on round-trip time-of-arrival ranging measurement and RLS (recursive least square) positioning. Using simulations, we investigate the location scheme performance as a function of a number of parameters such as the reference nodes' density and power range. The simulation results prove the effectiveness of our location scheme.