A Distributed Inter-Cell Interference Coordination Scheme in Downlink Multicell OFDMA Systems

In this paper, the inter-cell interference coordination (ICIC) is investigated for the downlink transmission in OFDMA-based multi-cellular systems. The utility function is introduced to balance efficiency and fairness. Firstly, the system model is built based on the resource allocation rules of soft frequency reuse (SFR) and the utility-based optimization problem is formulated. Secondly, the problem is simplified and analyzed in the 3-cell layout to obtain a local optimizing allocation rule. Thirdly, a distributed heuristic ICIC scheme is developed in which a part of the spectrum is defined to be the spectrum pool. Cells make occupation decisions of the spectrum pool according to locally available information of traffic load. The proposed scheme has little signaling overhead and low complexity. Simulation results validate it can improve the cell edge throughput performance effectively.