Challenge-Response PLA with Amplify and Forward Relay: Design and Experimental Validation

Future wireless communication systems will require new security mechanisms to support devices with limited capabilities. We consider a wireless communication link assisted by an amplify-and-forward relay and propose a novel challenge-response physical layer authentication (PLA) mechanism. The authentication-verifying receiver randomly configures the relay and verifies that the measured received power changes accordingly. We design the distribution of the random choice to maximize the average capacity while ensuring an upper bound on misdetection and false alarm probabilities of the authentication test. The performance is assessed by experiments in an indoor scenario with a relay, operating at the 60 GHz Industrial Medical and Scientific frequency band, equipped with 16 antennas organized in a planar array. The trade-off between achieved rate and security is investigated.