Pairwise Distance and Position Estimators From Differences in UWB Channels to Observers

TL;DR

This paper introduces novel estimators for relative positioning of wireless nodes using UWB channel differences, effective even without line-of-sight or precise synchronization, promising low-cost, accurate localization in complex environments.

Contribution

The paper presents new distance and position estimators based on multipath component delays and directions, applicable with known or unknown MPC associations, without requiring environment or observer location knowledge.

Findings

Estimators perform well without line-of-sight conditions.

Position estimators show high potential accuracy.

Methods do not require precise synchronization or environment knowledge.

Abstract

We consider the problem of obtaining relative location information between two wireless nodes from the differences in their ultra-wideband (UWB) channels to observer nodes. Our approach focuses on the delays of multipath components (MPCs) extracted from the observed channels. For the two different cases of known and unknown MPC association between these channels, we present estimators for the distance and for the relative position vector between the two nodes. The position estimators require both MPC directions and MPC delays as input. All presented estimators exhibit very desirable technological properties: they do not require line-of-sight conditions, precise synchronization, or knowledge about the observer locations or about the environment. These advantages could enable low-cost wireless network localization in dynamic multipath environments. The exposition is complemented by a numerical evaluation of the estimation accuracy using random sampling, where especially the position estimators show the potential for great accuracy.