摘要
考虑到未来大型物联网中待服务用户的异构性(接收机产自不同制造商,且具有不同结构、不同功能)和服务需求的多样性,针对功率分割(PS)用户和时间切换(TS)用户共存的异构场景,提出一种IRS辅助的无线携能通信(SWIPT)非正交多址接入(NOMA)通信系统模型。在满足两类用户服务质量的条件下,通过联合优化基站的有源波束成形、IRS的无源相移矩阵、PS用户的功率分割系数、TS用户时间切换系数以及两类用户的串行干扰消除解码顺序来最小化基站的发射功率。为解决该非凸问题,采用基于连续凸逼近的交替迭代方法将问题拆分成多个子问题。针对IRS相移的无源波束成形优化子问题,采用连续秩一约束松弛方法求解。仿真结果表明,IRS辅助的通信系统基站发射功率明显低于无IRS方案;IRS辅助的NOMA通信系统基站发射功率低于IRS辅助的正交多址接入通信系统;IRS辅助的PS-SWIPT系统基站发射功率低于IRS辅助的TS-SWIPT系统。
Considering the heterogeneity of users to be served(different receiver structures)and the diversity of service requirements in the future large-scale Internet of things,an IRS-assisted simultaneous wireless information and power transfer(SWIPT)non-orthogonal multiple access(NOMA)communication system model for heterogeneous scenarios where power splitting(PS)users and time switching(TS)users coexist was proposed.Under the condition of satisfying the quality of service of the proposed scheme was better than other schemes two types of users,the transmit power of the base station was minimized by jointly optimizing the active beamforming of the base station,the passive phase shift matrix of the IRS,the power splitting ratio of the PS users,the time switching coefficient of the TS users and the successive interference cancellation decoding order of the two types of users.In order to solve the non-convex problem,an alternating iterative method based on successive convex approximation was used to split the problem into multiple subproblems.For the passive beamforming optimization sub-problem of IRS phase shift,the sequential rank-one constraint relaxation approach was used to solve it.Simulation results show that the base station transmission power of the IRSassisted communication system is significantly lower than that of the non-IRS scheme,the base station transmission power of IRS-assisted NOMA communication system is lower than that of IRS-assisted orthogonal multiple access communication system,the base station transmission power of the IRS-assisted PS-SWIPT system is lower than that of the IRS-assisted TS-SWIPT system.
作者
季薇
刘子卿
JI Wei;LIU Ziqing(College of Telecommunications and Information Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China)
出处
《通信学报》
EI
CSCD
北大核心
2024年第4期39-53,共15页
Journal on Communications
基金
国家自然科学基金资助项目(No.61871238,No.62271265)。
