Energy-Efficient THz NOMA for SWIPT-Aided Miniature UAV Networks

Abstract

This letter focuses on maximizing the energy efficiency (EE) of a cooperative network involving miniature unmanned aerial vehicles (UAV) operating at terahertz (THz) frequencies, leveraging simultaneous wireless information and power transfer (SWIPT). In this context, the considered system encompasses a source node that adopts SWIPT, thereby allowing the miniature UAV to receive information and power simultaneously. The harvested energy is then employed to relay data to designated destination nodes. The EE of the system is maximized by optimizing non-orthogonal multiple access (NOMA) power allocation coefficients, SWIPT power splitting (PS) ratios, and UAV's trajectory. This optimization problem is solved in two stages. First, the PS ratios and trajectory are optimized using a successive convex approximation. Next, NOMA power coefficients are optimized using a quadratic transform approach. Simulation results validate the effectiveness of the proposed algorithm compared to baselines.