Physical Layer Security for Hybrid Reconfigurable Intelligent Surface and Artificial Noise Assisted Communication
A hybrid active-passive Reconfigurable Intelligent reflecting Surface(RIS)and Artificial Noise(AN)based transmission scheme is proposed for the secret communication of the RIS assisted wireless communication system.Aiming at maximizing the secrecy rate,a joint optimization problem over the transmit beamforming and AN vector of the base station and the reflecting coefficient matrix of the RIS is formulated.Then,the Alternating Optimization(AO)method,the weighted Minimum Mean Square Error(MMSE)algorithm and the semi-definite relaxation algorithm are proposed to solve this non-convex optimization problem with highly-coupled variables.The simulation results show that the proposed hybrid RIS and AN based scheme can efficiently improve the secrecy rate of the considered system and overcome the secrecy rate decrease due to the"double fading"effect of the passive RIS.Compared with the full active RIS,the proposed scheme achieves higher energy efficiency.
NETL
NSTL
万方数据
