High Precision TOA-based Direct Localization of Multiple Sources in Multipath

TL;DR

This paper introduces a novel direct localization method for multiple RF sources in multipath environments, leveraging sparse modeling and atomic norm minimization to improve accuracy over complex indoor and outdoor scenarios.

Contribution

It models source localization in a sparse framework, distinguishing LOS from NLOS paths, and provides theoretical guarantees for accurate recovery using atomic norm minimization.

Findings

High accuracy localization in complex multipath scenes

Effective differentiation of LOS and NLOS signals

Theoretical guarantees for source recovery

Abstract

Localization of radio frequency sources over multipath channels is a difficult problem arising in applications such as outdoor or indoor gelocation. Common approaches that combine ad-hoc methods for multipath mitigation with indirect localization relying on intermediary parameters such as time-of-arrivals, time difference of arrivals or received signal strengths, provide limited performance. This work models the localization of known waveforms over unknown multipath channels in a sparse framework, and develops a direct approach in which multiple sources are localized jointly, directly from observations obtained at distributed sources. The proposed approach exploits channel properties that enable to distinguish line-of-sight (LOS) from non-LOS signal paths. Theoretical guarantees are established for correct recovery of the sources' locations by atomic norm minimization. A second-order cone-based algorithm is developed to produce the optimal atomic decomposition, and it is shown to produce high accuracy location estimates over complex scenes, in which sources are subject to diverse multipath conditions, including lack of LOS.