多臂赌博机赋能的IRS辅助MISO系统传输方案设计  

A multi-armed bandits empowered transmission scheme for IRS-assisted MISO system

作　　者：宋云超 李浩 梁汇彬 汪革 SONG Yunchao;LI Hao;LIANG Huibin;WANG Ge(College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210023,China)

机构地区：[1]南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院,江苏南京210023

出　　处：《物联网学报》2025年第1期128-137,共10页Chinese Journal on Internet of Things

基　　金：国家自然科学基金资助项目(No.62101282)。

摘　　要：智能反射面(IRS,intelligent reflecting surface)是一种能够提升毫米波通信性能并应对传输挑战的技术。然而,传统方法在联合优化预编码和IRS相移时需要准确的信道状态信息,导频消耗随着基站天线数和IRS元件数的增加而增大。为降低导频,提出了一种基于多臂赌博机(MAB,multi-armed bandit)的传输设计方案。具体而言,在IRS辅助单天线用户下行通信系统中,通过双时间尺度的方法,将IRS相移和预编码波束成形问题解耦。利用强化学习中的上下文MAB算法,在每个相干时间块内根据上下文信息和奖励反馈来设计IRS相移矩阵。接着,采用迫零方法设计预编码,并引入贪婪法来选择每一时刻的动作,以避免陷入局部最优。仿真结果表明,与现有的算法相比,所提算法能够实现更高的有效频谱效率。Intelligent reflecting surface(IRS)is an effective technology that can enhance millimeter-wave communication performance and address transmission challenges.However,conventional methods require accurate channel state information when jointly optimizing precoding and IRS phase shifting,and pilot consumption increases with the number of base station antennas and IRS components.To reduce pilot overhead,a transmission design scheme based on multi-armed bandit(MAB)was proposed.Specifically,in IRS-assisted single antenna user downlink communication systems,the problem of IRS phase shift design and precoding beamforming was decoupled through a dual time scale approach.Using the contextual MAB algorithm in reinforcement learning,the IRS phase shift matrix was designed within each coherent time block based on contextual information and reward feedback.Next,the zero forcing method was used to design precoding,and the greedy method was introduced to select actions at each moment to avoid getting stuck in local optima.The simulation results show that the proposed algorithm can achieve higher effective spectral efficiency than the existing algorithms.

关 键 词：毫米波 智能反射面 多输入单输出 上下文多臂赌博机 

分 类 号：TN929.5[电子电信—通信与信息系统]