User Fairness based Energy Efficient Power Allocation for Downlink Cellular NOMA System

The cellular technology in 5G has raised demand for high data rate which requires more resources such as bandwidth and base station (BS) power. But, availability of these resources are generally limited. Shortage of available channel impairs user accommodation within the cell while increased power consumption causes overloading of the BS involving emission of CO2 gas thereby causing adverse effect on the environment and human health. Therefore, making an energy-efficient non-orthogonal multiple access (NOMA) system is an essential need of the day. In view of this, in this paper, we propose a channel assignment technique with user fairness-based power allocation strategy for NOMA cellular network in which the objective is to maximize the overall energy efficiency (EE) while satisfying the minimum required data rate within the available limited power budget of the base station. As a solution to this problem, an iterative algorithm is suggested. The performance efficiency of the proposed algorithm is analyzed, verified and compared with conventional schemes via simulation experiments.