Abstract
Ultra Wide-band (UWB) indoor positioning provides very accurate location estimates because of extremely narrow time resolution of UWB signals. The most critical part is the estimation of the time of arrival (ToA). In this paper, we propose a novel method for ToA estimation that achieves high accuracy with sub-Nyquist sampling. The proposed method first determines a coarse estimate of ToA by using an energy detection algorithm. Thereafter the power delay profile (PDP) parameters are used to find out the final estimate of ToA. A Cramer-Rao lower bound is analytically derived for the proposed scheme. The simulation results, using the UWB channel models and measured channel responses in an indoor channel environment, show the effectiveness of the scheme in both LOS and NLOS scenarios.