Improved Frequency Reuse through Sector Offset Configuration in LTE Heterogeneous Networks

In order to realise the potential benefits of cochannel deployments in Heterogeneous Networks (HetNets) and achieve an efficient spectrum reuse, an end-to-end optimisation of small cell and macrocell network operation is highly regarded. In this paper, a novel cellular network and frequency reuse configuration for both small cells and macrocells is proposed to address inter-cell interference and handover issues in HetNets. The proposed configuration complements Release 10 enhanced Intercell Interference Coordination (eICIC), and further increases its inter-cell interference mitigation capabilities. Simulations for LTE show that compared to a network that uses standardised Release 10 Almost Blank Subframes (ABS), the proposed configuration can improve expanded-region User Equipments (UEs) performance by 50% for a given ABS duty cycle. Moreover, for a given targeted expanded-region UEs performance, the proposed configuration can decrease the ABS duty cycle by up to a factor of 2, thus improving macrocell UEs performance up to 31 %. The proposed configuration also mitigates handover failures (HOFs) by 46 %, since handovers start at a higher signal quality.