  In this paper, we propose a movable antenna (MA) enhanced scheme for wireless
powered mobile edge computing (WP-MEC) system, where the hybrid access point
(HAP) equipped with multiple MAs first emits wireless energy to charge wireless
devices (WDs), and then receives the offloaded tasks from the WDs for edge
computing. The MAs deployed at the HAP enhance the spatial degrees of freedom
(DoFs) by flexibly adjusting the positions of MAs within an available region,
thereby improving the efficiency of both downlink wireless energy transfer
(WPT) and uplink task offloading. To balance the performance enhancement
against the implementation intricacy, we further propose three types of MA
positioning configurations, i.e., dynamic MA positioning, semi-dynamic MA
positioning, and static MA positioning. In addition, the non-linear power
conversion of energy harvesting (EH) circuits at the WDs and the finite
computing capability at the edge server are taken into account. Our objective
is to maximize the sum computational rate (SCR) by jointly optimizing the time
allocation, positions of MAs, energy beamforming matrix, receive combing
vectors, and offloading strategies of WDs. To solve the non-convex problems,
efficient alternating optimization (AO) frameworks are proposed. Moreover, we
propose a hybrid algorithm of particle swarm optimization with variable local
search (PSO-VLS) to solve the sub-problem of MA positioning. Numerical results
validate the superiority of exploiting MAs over the fixed-position antennas
(FPAs) for enhancing the SCR performance of WP-MEC systems.
