Intelligent reflecting surface-aided MIMO secrecy rate maximization

This paper considers the intelligent reflecting surface-aided MIMO secrecy rate maximization. We apply the alternating optimization to maximize the secrecy rate of the MIMO wiretap channels. We first provide the closed-form solution to each subproblem of optimizing reflecting unit coefficient and show that the sequence generated by the coordinate descent method converges to a stationary point of the main optimization problem. Numerical results show that the intelligent reflecting surface significantly increases secrecy rates in MIMO wiretap channels.