Energy-Efficient Resource Allocation for Simultaneous Wireless Information and Power Transfer in GFDM Cooperative Communications

Simultaneous wireless information and power transfer (SWIPT) for generalized frequency division multiplexing (GFDM) cooperative communications is proposed to save consumed energy of relay and destination. GFDM subsymbols are allocated for information decoding (ID) and energy harvesting (EH), respectively. Energy efficiency of SWIPT based GFDM system is maximized by jointly optimizing subsymbol and power allocations for ID and EH. A joint optimization algorithm is proposed to obtain the optimal solution to the energy-efficiency optimization problem. Simulation results show that energy efficiency of this scheme is 5bps/J/Hz higher than that of power-splitting SWIPT at total transmit power of 5mW.

I. Introduction

Generalized frequency division multiplexing (GFDM) is one of the candidate multi-carrier communication schemes for 5G communications [1]. Compared with the Orthogonal Frequency Division Multiplexing (OFDM), it has the advantages of high spectrum utilization [2], low out-of-band radiation [3], low peak-to-average ratio and setting parameters that meet the requirements of different application scenarios [4]. Different from OFDM, GFDM can use its time-frequency focusing to design a shaping filter suitable for channel delay, which can resist both inter-symbol interference and inter-carrier interference and thus obtain higher spectrum efficiency [5]. However, multi-carrier transmission may consume more energy compared with the single-carrier communication.