Multipath-Enhanced Device-Free Localization in Wideband Wireless Networks

TL;DR

This paper introduces a multipath-enhanced device-free localization system that leverages multipath propagation in wireless networks to improve accuracy and extend the observation area, especially indoors.

Contribution

It proposes a novel method to incorporate multipath components into localization, utilizing environmental information to geometrically derive propagation paths.

Findings

Improved localization accuracy with multipath information

Extended effective observation area indoors

Theoretical bounds show performance enhancement

Abstract

State-of-the-art device-free localization systems infer presence and location of users based on received signal strength measurements of line-of-sight links in wireless networks. In this letter, we propose to enhance device-free localization systems by exploiting multipath propagation between the individual network nodes. Particularly indoors, wireless propagation channels are characterized by multipath propagation, i.e., received signals comprise multipath components due to reflection and scattering. Given prior information about the surrounding environment, e.g., a floor plan, the individual propagation paths of multipath components can be derived geometrically. Inherently, these propagation paths differ spatially from the line-of-sight propagation path and can be considered as additional links in the wireless network. This extended network determines the novel multipath-enhanced device-free localization system. Using theoretical performance bounds on the localization error, we show that including multipath components into device-free localization systems improves the overall localization performance and extends the effective observation area significantly.