Integrative Ranging and Positioning for IR-UWB Wireless Sensor Networks

Sufficient intercommunication between ranging module and positioning module was lacked during the current research on the localization issue for IR-UWB wireless sensor networks. The idea of integrative ranging and positioning was proposed in this paper. The ranging module was designed to provide not only the range estimation results to the positioning module, but also the corresponding reliability evaluation results and NLOS identification results. Three positioning algorithms that differently utilize the ranging information were proposed, including LS, WLS, and MLE. Simulation results show that WLS and MLE greatly outperform LS. Since the computation complexity of WLS is much less than MLE, WLS is more appropriate for practical application. The effects of pulse energy and NLOS ratio of anchor nodes on positioning performance were also investigated, some useful results which can guide the practical design are drawn.