Research on IRS-assisted NOMA energy efficiency transmission scheme

Xiaojuan Bai; Fei Bao; Xingxing Li

doi:10.54097/jceim.v11i2.11756

Authors

Xiaojuan Bai
Fei Bao
Xingxing Li

DOI:

https://doi.org/10.54097/jceim.v11i2.11756

Keywords:

Intelligent reflect surface, Non-orthogonal multiple access, Energy efficiency, Power allocation, Phase shift optimization

Abstract

The combination of intelligent reflect surface (IRS) and non-orthogonal multiple access (NOMA) is an effective solution to improve communication coverage and energy efficiency. Energy efficiency (EE) is an important performance index of communication system. In this paper, the IRS-assisted NOMA downlink multi-cluster system is taken as the research object. Under the requirement of user quality of services (QoS), the energy efficiency of the system is maximized by alternately optimizing the power allocation of the base station and the phase shift of the IRS passive components. However, the non-convexity of the optimization problem and the coupling of the optimization variables make the optimization problem difficult to solve. Therefore, a new alternating optimization scheme is proposed in this paper. The problem is divided into two sub-problems, which are solved by first-order Taylor expansion method, successive convex approximation method and semi-definite relaxation method respectively. The simulation results show that the IRS-NOMA transmission scheme proposed in this paper has better performance than other transmission schemes of RIS-NOMA system.

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