r-RADAR: Obtain the Maximum Throughput When an Energy Harvesting Relay Node is Applied in Multiuser OFDMA Networks

—The joint resource allocation for multiuser Orthogonal Frequency Division Multiple Access (OFDMA) relay networks is studied in the paper, where the relay node has renewable energy supplies and can be driven by energy collected from Radio Frequency (RF) signals from the source node. The relay node with green energy supplies uses Power Splitting (PS) scheme for Simultaneous of Wireless Information and Power Transfer (SWIPT). The joint resource allocation problem is formulated to maximize the throughput under several constraints including subcarrier pairing, power splitting ratio, power allocation, and subcarrier pairing allocation while satisfying data rate requirements for multiuser OFDMA relay networks. Due to the specialized problem is non-convex and difficult to be solved in finite polynomial time, a reconfigurable resource allocation by using the decoupling approach in a framework of repetitive (r-RADAR) algorithm with low computational complexity is proposed in the paper, which takes advantage of the unique problem structure and reduce the domain of search space. The global optimality is theoretically proven and well obtained when we using r-RADAR algorithm. Simulation results further validate the better performances of our proposed r-RADAR algorithm when it is compared to the other two related benchmark algorithms.