Sum Rate and Fairness Optimization for Intelligent Reflecting Surface Aided Multiuser Systems

In this paper, we propose a new beamforming design for intelligent reflecting surface (IRS) assisted multi-user systems where a base station with multiple antennas support several users with an aid of an IRS. We jointly optimize the sum rate and the user fairness by adopting a single objective function. To tackle the non-convex problem, we present an iterative algorithm based on the successive convex approximation method. Simulation results demonstrate that the proposed scheme outperforms other conventional IRS based schemes in terms of both the sum-rate and user fairness.