posted on 2019-04-04, 11:54authored byJ Tang, J Luo, M Liu, DKC So, E Alsusa, G Chen, KK Wong, J Chambers
IEEE The combination of simultaneous wireless information and power transfer (SWIPT) and non-orthogonal multiple access (NOMA) is a potential solution to improve spectral efficiency (SE) and energy efficiency (EE) of the upcoming fifth generation (5G) networks, especially in order to support the functionality of the Internet of things (IoT) and the massive machine-type communications (mMTC) scenarios. In this paper, we investigate joint power allocation and time switching (TS) control for EE optimization in a TS-based SWIPT NOMA system. Our aim is to optimize the EE of the system whilst satisfying the constraints on maximum transmit power budget, minimum data rate and minimum harvested energy per-terminal. The considered EE optimization problem is neither linear nor convex involving joint optimization of power allocation and time switching factors, and thus is extremely difficult to solve directly. In order to tackle this problem, we develop a dual-layer algorithm where Dinkelbach method is employed both in the inner-layer to optimize the power allocation and in the outer-layer to control the time switching assignment. Furthermore, a simplified but practical special case with equal time switching factors in all terminals is considered. Numerical results validate the theoretical findings and demonstrate that significant performance gain over orthogonal multiple access (OMA) scheme in terms of EE can be achieved by the proposed algorithms in a SWIPT-enabled NOMA system.
Funding
Engineering and Physical Sciences Research Council; National Natural Science Foundation of China
History
Citation
IEEE Journal on Selected Topics in Signal Processing, 2019, in press
Author affiliation
/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Engineering
Version
AM (Accepted Manuscript)
Published in
IEEE Journal on Selected Topics in Signal Processing
Publisher
Institute of Electrical and Electronics Engineers (IEEE)