智能反射面辅助的非正交多址系统高能效传输方案研究  

Research on energy-efficient transmission scheme for IRS-assisted NOMA systems

作　　者：张诚 王鸿 ZHANG Cheng;WANG Hong(College of Telecommunication&Information Engineering,Nanjing LDiversity of Posts and Telecommunications,Nanjing 210003,P.R.China)

机构地区：[1]南京邮电大学通信与信息工程学院,南京210003

出　　处：《重庆邮电大学学报（自然科学版）》2023年第1期16-22,共7页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：国家自然科学基金(61801246)。

摘　　要：针对基站(base station, BS)功率分配和智能反射面(intelligent reflecting surface, IRS)相移相互耦合的非凸优化问题,提出一种新的交替优化方案,即交替运用最优能量效率(energy efficiency, EE)功率分配算法和块坐标上升(block coordinate ascent, BCA)技术求解功率分配与相位偏移问题,直至优化的目标值收敛。仿真结果表明,与IRS辅助的正交多址接入(orthogonal multiple access, OMA)、随机相移的IRS辅助非正交多址接入(non-orthogonal multiple access, NOMA)、无IRS辅助的纯NOMA接入技术相比,提出的IRS-NOMA传输方案能够显著提升系统的EE性能。The integration of intelligent reflecting surface(IRS) into non-orthogonal multiple access(NOMA) system is an effective solution to improve the spectrum and energy efficiency(EE) for future communications. In this paper, an EE maximization problem of downlink IRS-assisted NOMA system is formulated, in which both the minimum data rate requirement of each user and the maximum transmit power constraint of the base station(BS) are considered. For this non-convex optimization problem in which the BS power allocation and IRS phase shift are coupled, a novel alternating optimization scheme is proposed, that is, an EE-optimal power allocation algorithm and a block coordinate ascent(BCA) technique are alternatively used to solve the power assignment and the phase shift subproblems until the convergence is reached. Simulation results show that the proposed IRS-NOMA transmission method is capable of improving the EE performance significantly when compared with the IRS-assisted orthogonal multiple access(OMA), the IRS-NOMA with random phase shifts, and the traditional NOMA without IRS.

关 键 词：智能反射面 非正交多址接入 能量效率 相移优化 块坐标上升 

分 类 号：TN929.5[电子电信—通信与信息系统]