Optimal beam-focusing design for 6G near-field SWIPT systems

Abstract

This letter investigates a novel 6G near-field simultaneous wireless information and power transfer (SWIPT) system, in which a single hybrid transmitter, equipped with an extremely large-scale antenna array, concurrently provides wireless data and energy access to mobile terminals. In this pioneering scenario, we delve into the optimal beam-focusing design with the goal of maximizing the weighted-sum energy harvested by all energy receivers while ensuring the achievable rate requirements of information receivers. Despite the inherent non-convexity of the associated optimization problem, we achieve a globally optimal solution by employing the technique of semi-definite relaxation. Our numerical results affirm the remarkable effectiveness of the proposed optimal beam-focusing design.