Holistic Optimization of Rate and EE in UAV-Assisted HetNets

Technological advancements are driving a surge in demand for real-time interactive applications, high-speed transmissions, and innovative network designs, necessitating enhancements in both network rate and energy efficiency (EE) to deliver immersive user experiences. This paper introduces a novel network model based unique mathematical optimization problem, employing advanced techniques such as phone user clustering (PUC)-based downlink hybrid multiple access (H-MA) within an unmanned aerial vehicle (UAV)-assisted heterogeneous network (HetNet). The objective is to concurrently improve network rate and EE by optimizing performance indicators (PIs), including phone user (PU) admission in clusters, PU association with cells, power allocation to clusters and PUs, PU fair association with cell (PUFAC), and quality of service (QoS) of PUs. The formulated optimization problem, a mixed-integer non-linear programming (MINLP) problem, is effectively addressed using an outer approximation algorithm (OAA). The paper concludes with a comprehensive assessment of the proposed PUC-based downlink H-MA technique in a UAV-assisted HetNet, considering all PIs. Additionally, it provides a performance comparison against an macro cell (MC)-only network and a HetN et, demonstrating the superior performance of the proposed technique across various metrics, including rate, EE, PU admission, PU-cell association, power allocation, PUFAC, and QoS in a UAV-assisted HetNet compared to both the MC-only network and HetNet.