Analysis of position-related information in measured UWB indoor channels

Conventional radio-based indoor localization systems often only make use of the direct signal path between an agent and the anchor nodes. Therefore, performance can deteriorate in non-line-of-sight situations, even though reflected multipath-components carry useful location-dependent information. Using ultra-wideband signals, these components become resolvable. Bringing together previously obtained results on the Cramér-Rao bound on the position error and measurement data along a reference trajectory, we present a methodology for quantifying the position-related information contained in UWB indoor channels. An explicit model for the diffuse part of the channel enables to evaluate its importance realistically. Experimental results verify prior theoretical work. Important parameters and their influence on the system performance are discussed.