Max–Min Fairness Design for MIMO Interference Channels: A Minorization–Maximization Approach

We address the problem of linear precoder (beamformer) design in a multiple-input multiple-output interference channel. The aim is to design the transmit covariance matrices in order to achieve max-min utility fairness for all users. The corresponding optimization problem is non-convex and NP-hard in general. We devise an efficient algorithm based on the minorization-maximization technique to obtain quality solutions to this problem. The proposed method solves a second-order cone convex program at each iteration. We prove that the devised method converges to stationary points of the problem. We also extend our algorithm to the case where there are uncertainties in the noise covariance matrices or channel state information. Simulation results show the effectiveness of the proposed method compared with its main competitor.