Physical-Layer Authentication for Multi-Carrier Transmission

We propose a novel physical-layer challenge-response authentication scheme for multi-carrier transmission. This new scheme exploits both the reciprocity and randomness of the phase responses over multi-carrier channels, and ensures strong security since the channel-phase response is very sensitive to the distance between the transmitter and receiver. A binary hypothesis testing approach is formulated for authentication, which shows a close connection to the problem of pseudo-noise (PN) code acquisition. The proposed scheme can achieve desirable authentication performance even at the signal-to-noise ratio of 5 dB for Rayleigh fading channels.