A distributed dynamic ABS ratio setting scheme for macro-femto heterogeneous networks

In co-channel deployment of macrocell and indoor femtocells, almost blank subframe (ABS) is considered as an effective enhanced inter-cell interference coordination strategy for mitigating downlink cross-tier interference. In this paper, a novel distributed dynamic ABS ratio setting scheme is proposed for dense residential femtocell deployment with closed subscriber group configuration. Both the overall cell throughput and fairness index are employed to judge the status of the environment around each femtocell, which decides whether and how to change ABS ratios. Simulation results show that the proposed scheme outperforms other static settings, and provides remarkable improvement on cell edge performance with little overall throughput cost.