Anchor-Free Localization Algorithm with Low-Complexity Method for Node Distance Estimation Enhancement Using ToA

Abstract

We introduce the anchor-free localization algorithm using Time of Arrival node distance estimation technique. ToA using Ultra Wide-Band communication technology is preferred, because it is one of the most promising approaches of the mobile positioning and has a great potential for accurate ranging especially in the harsh indoor environment. Due to very wide bandwidth of the UWB systems, these systems are capable resolving individual multipath components in the received Channel Impulse Response and determining their time of their arrival very precisely. We propose a low-complexity method for mitigation of the Undetected Direct Path effect which causes considerable errors in the node distance estimation. The method combines the mean of the time delay differences of the reflected paths detected in the measured channel power delay profile, overall channel impulse response length and Mean Excess Delay calculated relative to the first detected path. The positioning algorithm has been simulated in LoS, NLoS(OLoS) and NLoS(UDP) communication conditions. © Springer-Verlag Berlin Heidelberg 2013.