A new uplink interference mitigation in HetNets using macro uplink subframe muting

In this paper, we propose a new method to combat uplink interference for small cell networks and to improve the downlink performance for macro-cell users. The focus of this new method is to tackle directly the uplink problem without having recourse to Cell Range Expansion (CRE) and Almost Blank Subframe (ABS) techniques. The solution consists in reserving a group of uplink subframes during which the users attached to macro cells are partially muted allowing the small-cell users to be served with lower interference. In order to validate the proposed technique and compare it with the available methods, LTE-Sim [1] simulator was deployed, customized and enhanced to include all scenarios proposed in this paper. A major contribution to the system level simulation source code and mainly to the uplink part, was made in order to enhance the uplink algorithm available within LTE-Sim and to have it aligned with real performances of the LTE standard in the uplink. Using the simulation results, we identify the network conditions where the proposed method outperforms standard eICIC.