Relay-Assisted Multiuser Wireless Powered Communication with Processing Costs

This paper studies a relay-assisted wireless powered communication network (R-WPCN), consisting of multiple source-destination pairs assisted by a hybrid relay node (HRN), where the HRN first charges the sources by wireless power transfer (WPT), and then forwards the information from the sources to their destinations through time division multiple access (TDMA). The practical non-zero processing costs at the wireless- powered sources are taken into account. The aim of this paper is to maximize the sum-rate of all transmission pairs by jointly optimizing the transmission time and power. By deriving some useful properties of the problem, we design an efficient algorithm to solve this non-convex problem optimally. Furthermore, a suboptimal algorithm is proposed to reduce the complexity. Extensive simulation results demonstrate the effectiveness of the proposed algorithms.