Analysis of the Energy-Cognizant User Association and Load Distribution in a D2D-Enabled 5G Multi-Tier Heterogeneous Cellular Network

For the evolving heterogeneous or multi-tier cellular networks biased factor or power-based user association is one of the most prominent user association schemes to enhance the network coverage. Whereas, device-to-device (D2D) communication enhances the coverage of the cellular network by enabling direct communication between user equipment when sufficient coverage is unavailable in case of a user and initiating communicating with another user having sufficient coverage from the base station. Therefore, the paper presented conceptual research and preliminary analysis considering a three-tier heterogeneous network formed by macro, micro, and femto tiers to analyze the user association with and without enabling D2D communication. The work moreover aimed to measure energy consumption and load distribution i.e. the average number of users in a base station of a selected tier (kth tier).