Dynamic Frequency Reservation Scheme for Interference Coordination in LTE-Advanced Heterogeneous Networks

Heterogeneous networks are employed in the next generation communication systems to enhance area spectral efficiency (ASE) and reduce system cost. However, the cell splitting gain can only be achieved when both co-tier interference and cross-tier interference are properly handled. To reduce cross-tier interference on the low SINR and interference limited UEs, a dynamic scheme of frequency reservation for interference coordination (DFR-IC) is proposed in this paper. Two factors to model the co-tier and cross-tier interference ratio of user equipments (UEs), namely R_I^macro and R_I^pico, are introduced. Proper numbers of resource blocks (RBs) in each tier are reserved for these UEs to enhance their SINRs. Simulation results show that the proposed scheme can greatly improve the performance of the UEs at cell edge, but it decreases marginal throughput compared to full-reuse and non-reuse scheme.