ENERGY EFFICIENCY MAXIMIZATION IN RIS-AIDED NETWORKS WITH GLOBAL REFLECTION CONSTRAINTS

This work addresses the issue of energy efficiency maximization in a multi-user network aided by an RIS with global re- flection capabilities. Two optimization methods are proposed to jointly optimize the mobile users’ powers, the RISs coefficients, and the linear receive filters. Both methods are provably convergent and require only the solution of (a sequence of) convex optimization problems, thus having affordable complexity. The numerical results show that carefully optimizing the receive filters provides significant gains, especially with RISs with global reflection constraints.