PRSRTI: A Novel Device-Free Localization Method Using Phase Response Shift Based Radio Tomography Imaging

Abstract

Device-free localization (DFL) is a hot topic in passive sensing such as intrusion detection, pose estimation, and contact-tracing. To improve the performance, we propose a novel fine-grained DFL method using the phase response shift (PRS) to localize targets, which can mitigate the effect of multipath, and noise without phase ambiguity. The phases of received multi-frequency signals are linearly fitted as the phase response (PR). The shift of target-induced PR with respect to non-target PR is considered as the PRS. The PRSs at every location of the monitored area are observed with different length communication links, and are summarized as a PRS weight model. The PRS-based radio tomography imaging (PRSRTI) localization model is derived, and utilizes the PRS, and the weight model to localize targets. Experimental results validate that its performance is obviously higher than the received signal strength based radio tomography imaging (RTI).