Ultrawideband pulse correlation and distance error estimation

In a given number of wireless systems, and ultrawideband (UWB) in particular, a way to communicate between transceivers is by correlating received pulses with one or several referencepulse templates. The reference template(s) aim to give a good representation of the transmitted signal. However, even for unscattered signals, resulting from line-of-sight (LOS) transmissions, radiated pulses may differ as a function of the antennas’ angle of departure/capture or may “look different” due to limited spatial resolution at the receiver. As these inaccuracies are often neglected and may have an impact on the robustness of a communication’s link, unscattered LOS UWB measurements, from 3.5 GHz to 10.5 GHz, are used in this paper to explore: (i) the effects of correlating received signals with different pulse templates as a result of distance changes between antennas (shorter than the spatial resolution of the system) and different angles of antenna radiation/capture; and (ii) the error in distance prediction from a system relaying on peak detection and limited by its spatial resolution. As a result, pulse correlation values were found to fluctuate from one and up to a value of 0.4 in some cases. Also, errors in distance estimation were characterised against different interpolation factors, from which modelling parameters are presented.