Hybrid Channel Gain Access Cell Association for Load Balancing in Downlink LTE-Advanced HetNets

The LTE-Advanced HetNets deployment is meant to address the increasing demand for quality of service (QoS), high data rates, and coverage extension to mobile users especially in hotspot areas. One of the main challenges of the deployment, where different network tiers share spectrum, is how users associate with the cells to achieve load balancing for improving system performance. The importance of joint metrics based cell association is stressed here, by combining channel gain and channel access as a single metric to maximize the spectral efficiency as well as achieve a balanced load among the network tiers. The load balancing performance of the hybrid channel gain and access scheme was found to be midway when compared with the extreme cell association schemes: conventional reference signal receive power (RSRP) and the high bias RSRP. Although the cell edge users of the proposed scheme have the worst spectral efficiency performance compared to the interference-aware cell selection schemes considered in this work, the cell centre users exhibit the best spectral efficiency performance.