An Efficiency Maximization Design for SWIPT

A joint power splitting and beamforming design for multiuser multiple-input single-output (MISO) systems where receivers have capability of decoding information and harvesting energy simultaneously from received signals is considered. The objective is to maximize the ratio of the achieved utility to the total power consumption subject to harvested power requirements and power budget at a base station (BS). The utility function of interest combines the sum rate and the total harvested power. The design problem is nonconvex, and thus, global optimality is difficult to achieve. To solve this problem locally we first convert the problem into a more tractable form, and then propose an iterative algorithm which is guaranteed to achieve a Karush-Kuhn-Tucker solution. Numerical results are provided to demonstrate the superior performance of the proposed method.