On the Precise Phase Recovery for Physical-Layer Authentication in Dynamic Channels

Using the channel state information (CSI) for physical-layer authentication is a promising concept in order to distinguish between wireless transmitters. However, the phase of the CSI is usually impeded severely by random distortions. These distortions deteriorate the quality of the phase information significantly. To cope with this effect, in this paper, we propose a novel algorithm based on Kalman filtering and maximum-a-posteriori (MAP) estimation that takes the CSI from previous observations into account. By the simulation results we can show that the proposed algorithm performs better than state-of-the-art approaches specifically in the cases of multipath fading or selective filtering. This is true in both static and dynamic channel environments.