Discontinuous Reception Based Energy-Efficient User Association for 5G Heterogeneous Networks

The 5G Heterogeneous Network (HetNet) enables massive connections and diverse applications for User Equipments (UEs), leading to an exponential increase in data traffic. This surge results in extensive overloading at co-tier and inter-tier levels, inefficiencies in UE power usage at the cell edge, and complexities in Quality of Service (QoS) support. In this paper, we propose a scheme to address load balancing among Base Stations (BSs), while simultaneously improving power efficiency and ensuring QoS for UEs. The proposed heuristic scheme comprises three phases. The first phase optimizes the Discontinuous Reception (DRX) configuration parameters for UEs, the second phase evaluates overloading, and the third phase offloads data from overloaded BSs to other BSs. We categorize performance indicators into 1) User Performance Parameters (UPP), including DRX power saving, packet drop rate, and end-to-end delay, and 2) Network Performance Parameters (NPP), such as system throughput. To validate our scheme, we design an analytical model based on a two-dimensional continuous-time Markov chain (2D-CTMC) and a semi-Markov process. In addition, we implement a simulator to validate the scheme's performance. The results demonstrate that the proposed scheme significantly enhances performance in terms of UPP and NPP.