Energy Efficiency Optimization in SWIPT Enabled OFDM Systems

Abstract

With the rapid development of fifth generation(5G) mobile communication technology, the energy consumption of the system is also increasing. Radio Frequency (RF) energy harvesting technology can convert the collected radio frequency signal energy into electricity. Simultaneous Wireless Information and Power Transfer (SWIPT) technology is proposed based on the characteristics of RF signals conveying information and carrying energy at the same time. In this paper, SWIPT technology is applied to Orthogonal Frequency Division Multiplexing (OFDM) systems, the transmission scheme of OFDM downlink systems based on Power Splitting strategy is studied. Specifically, an energy efficiency optimization algorithm of SWIPT enabled OFDM system based on ellipsoid method is proposed. The complexity of the algorithm is closely related to the Lagrange multiplier dimension. The simulation results show that when the Lagrange multiplier dimension is not high, the algorithm can achieve faster convergence speed and reduce the algorithm complexity compared with the subgradient method.