Fairness-Aware Soft Frequency Reuse for Multi-Cell OFDMA Networks with Statistical CSI

Soft frequency reuse (SFR) is a widely adopted frequency reuse mechanism to mitigate inter-cell interference (ICI) in cellular networks, which splits resource blocks (RBs) into two groups to serve cell-edge and cell-center users, respectively. In this paper, the joint design of RB grouping, frequency and power allocation is investigated for downlink transmission in the SFR-based multi-cell networks, where the imperfect knowledge of the statistical channel state information (S-CSI) is considered. Firstly, we derive a closed-form ergodic rate and propose a centralized iterative scheme for maximizing the minimum user ergodic rate to achieve user fairness using successive convex approximation (SCA). Furthermore, to facilitate practical implementation, a decentralized scheme is proposed, where the problem is refor-mulated as a global consensus problem and solved by exploiting alternating direction method of multipliers (ADMM). Simulation results demonstrate that our proposed schemes outperform the state-of-the-art counterpart.