Decentralized Beamforming Design for Intelligent Reflecting Surface-Enhanced Cell-Free Networks

Cell-free networks are considered to be a promising distributed network architecture satisfy the increasing number of users and high rate expectations in beyond-5G systems. However, further enhance capacity, an high-cost base stations (BSs) is required. To address this problem inspired by cost-effective intelligent reflecting surface (IRS) technique, we propose fully decentralized design framework for cooperative beamforming IRS-aided cell-free networks. We first transform centralized weighted sum-rate maximization into tractable consensus optimization problem, then incremental alternating direction method multipliers (ADMM) algorithm proposed locally update beamformer. The complexity convergence analyzed, these results show that performance new scheme can asymptotically approach one as iterations increases. Results also IRSs significantly increase system outperforms existing methods.