Reconfigurable Intelligent Surface Assisted Physical Layer Key Generation from Wireless Channels

This paper proposes a reconfigurable intelligent surface (RIS) assisted physical layer key generation (PKG) scheme to increase the key generation rate (KGR). Firstly, we provide a high-rate key generation protocol that rapidly and randomly switches the phase of RIS elements. Then, we analyze the key information leaked to passive eavesdroppers and give the closed-form expression of KGR when the number of RIS elements is sufficiently large. Monte Carlo simulation and numerical results show that our proposed scheme can boost KGR in a static environment.