Physical layer authentication for 5G/6G millimeter wave communications by using channel sparsity

This paper proposes a comprehensive study for the physical layer channel based authentication (PLA) designs in mmWave communications, which reveals the principles that how does the sparse properties of mmWave channel can benefit the PLA designs and performance. First, by fully investigating the channel perturbations of mmWave channel caused by the environmental changes within the channel coherence time, the generalized detection designs are investigated for mmWave channels. In general, it shows that the mmWave channel perturbations will seriously degrade the detection performance. To solve this problem, a lightweight but effective PLA scheme is proposed by fully utilizing the sparsity of mmWave channel. The key physical factors that impact the detection performance are fully investigated by conducting thoroughly theoretical analysis and simulations, and the detection spoofing probability of the scheme is show to be higher than 95%, while keeping the probability of false rate below 1%. The study indicates that channel sparsity is with great potential to design lightweight but effective PLA mechanisms for the future mmWave communication systems.