Wireless Powered Relaying for Multiuser Transmission

This paper studies a relay-assisted wireless powered communication network (R-WPCN) consisting of multiple source-destination pairs and a hybrid relay node (HRN). We consider a "charge-then-forward" protocol at the HRN, in which the HRN with constant energy supply first acts as an energy transmitter to charge the sources, and then forwards the information from the sources to their destinations through frequency division multiple access (FDMA). Our goal is to maximize the sum-rate of all transmission pairs by jointly optimizing the time, frequency and power resources.We solve this non-convex problem optimally by the Lagrange duality method. Furthermore, a suboptimal algorithm is proposed to tradeoff the complexity and performance. Finally, the simulation results validate the effectiveness of the proposed schemes.