A Countermeasure Against RIS Jamming Attack in Physical-Layer Key Generation

The attacker can manipulate a reconfigurable intelligent surface (RIS) to jamming attack to break the channel reciprocity, resulting in an increasing key disagreement rate (KDR) to interrupt the physical layer key generation (PKG). In this letter, a countermeasure for PKG is proposed to resist the RIS jamming attack. The proposed countermeasure includes the atomic norm minimization (ANM)-based multipath separation algorithm and statistic feature-based path detection algorithm, which can reconstruct the reciprocal channel without needing a wide frequency band. Simulation results show that the proposed countermeasure can significantly reduce KDR from 0.33 to 0.03 when SNR is 10 dB and achieve an excellent key generation rate (KGR) compared with existing schemes.