Harvested Power Fairness-Based Multi-Carrier NOMA IoT Networks With SWIPT

The integration of simultaneous wireless information and power transfer (SWIPT) in multi-carrier non-orthogonal multiple access (NOMA) systems has been recently investigated as a potential paradigm to improve the lifespan of energy-constrained Internet-of-Things networks. In this letter, we develop a fairness-aware design for a multi-carrier NOMA SWIPT-based system that attempts to maximize the minimum harvested power subject to quality-of-service constraints. With this design, each user’s power allocation, and the power splitting ratio are jointly computed by solving the corresponding optimization problem. To deal with the non-convexity nature of the formulated max-min optimization problem, an iterative mechanism with a second-order cone method is proposed. Simulation results indicate that our design maintains a better user fairness with respect to the harvested power.