UWB-TOA geolocation techniques in indoor environments

Abstract

Ultra-wideband (UWB) radio is a new carrierless communication scheme using impulses and is a candidate technology for future communication and ranging applications. In this paper, we consider the problem of node localizing in ad-hoc networks, in which positioning algorithm only exploits the high precision ranging capabilities offered by UWB and does not rely on GPS. A Time-of-Arrival (ToA) based ranging scheme using UWB radio link is proposed. In this paper, the problem of ToA estimation in multipath channels, source of estimation error are discussed. Two-way ranging (TWR) scheme was used for network synchronisation. Results show that the accuracy enhancement depends on two principal factors: the strength of multipath components and the variance of non-line-of-sight (NLOS) delays, which it shows that DS-UWB is best suited for ranging, due to its larger bandwidth and its higher frequencies of operation.