A Novel Dynamic Interference Coordination Scheme in Macrocell-Picocell Heterogeneous Networks

Picocell is an emerging and key item in LTE-Advanced system, for providing improved service coverage and high spectral efficiency with low power. However, in heterogeneous networks (Het-Nets) with macrocells and picocells, more complicated interference scenario can severely degrade the system performance, especially for system capacity and data rate of cell-edge users. Consequently, effective interference coordination schemes are in great demand to mitigate these interference problems. In this paper, we propose a new effective dynamic interference coordination scheme based on an innovative combination of soft frequency reuse (SFR) and improved Graph-based resource allocation in orthogonal frequency-division multiplexing access (OFDMA) macrocell-picocell network. The system-level simulation results show that the proposed scheme can achieve superior system performance improvements, higher cell-edge user data rate and more efficient frequency reuse, comparing with the time domain interference coordination Almost Blank Subframes (ABS) scheme and the conventional co-channel resource allocation scheme.