Weighted Sum Power Maximization for Movable Antenna Assisted SWIPT Networks

Simultaneous wireless information and power transfer (SWIPT) has been deemed as a key technology for future wireless powered networks. However, conventional SWIPT systems established on fixed-position antennas (FPAs) inherently undergo random wireless channel fading and cannot fully capture the channel variations in a local spatial region, which may result in high energy loss. To overcome this limitation, in this letter, we propose employing movable antenna (MA) to enhance the power transfer in a SWIPT network, where an MA array is deployed at an access point (AP) to serve multiple information decoding users (IDUs) and energy harvesting users (EHUs). Our objective is to maximize the weighted sum power received by EHUs by jointly designing the beamforming vectors of the AP and the positions of all MAs, subject to minimum signal-to-interference-plus-noise ratio (SINR) requirement of each IDU and maximum transmit power budget of the AP. To address the formulated non-convex problem, we propose an efficient algorithm to obtain a suboptimal solution by utilizing alternative optimization (AO) and successive convex approximation (SCA). Simulation results show that our proposed MA-assisted SWIPT system can remarkably enhance the weighted sum power compared to conventional FPA systems and other benchmark schemes.