Received signal strength based room level accuracy indoor localisation method

Our goal is to achieve room-level accuracy indoor localization of a target, using already deployed WLAN infrastructure, but without actually interfering with the network. The target device only performs passive scans of the existing access points. The currently used methods targets maximum precision and therefore use computationally intensive algorithms. In this paper, a simple covariance based method is presented which can achieve room level accuracy but in the meantime is simple to implement.