A Clustering-Based Algorithm for Device-Free Localization in IoT

Device-free localization (DFL) is an emerging technology for locating targets by monitoring the changes of radio frequency (RF) signals. It has many potential applications since this technology does not require the targets to participate in the localization effort by carrying any electronic device. In this paper, we propose a simple line-of-sight (LOS) model and hierarchical clustering filter and localization algorithm (HCFLA) to locate device-free targets. Radio signal strength (RSS) of wireless links in the internet of things was utilized to find out effected links whose attenuation is more than a threshold. We use the HCFLA algorithm to filter out the valueless points of the intersections of effected links, and then to infer the number and location of the targets with the remainder valuable points. The proposed algorithm is validated using measurement data. Results show that the proposed algorithm can detect the number of targets in high probability, and the localization average error reaches to 0.7 meter in 4.5* 4.5 meters indoor square area.