基于统计信道信息的智能反射面辅助物理层广播算法设计  

Physical Layer Broadcasting System Assisted by Intelligent Reflective Surface Based on Statistical Channel Information

作　　者：杨奎[1] 赵海燕 YANG Kui;ZHAO Haiyan(Southwest China Institute of Electronic Technology,Chengdu 610036,China;PLA Navy 701 Factory,Beijing 100016,China)

机构地区：[1]中国西南电子技术研究所,成都610036 [2]中国人民解放军海军701工厂,北京100016

出　　处：《电讯技术》2021年第10期1233-1237,共5页Telecommunication Engineering

摘　　要：智能反射面(Intelligent Reflective Surface,IRS)作为一种非常有前景的新型无线中继技术,可以改变无线传输环境,有效提升无线系统的频谱和能量效率。提出了一种基于统计信道的IRS辅助物理层广播系统的传输方案,在仅已知统计信道时,联合设计基站波束成形和IRS反射相位,最大化最小用户的各态历经容量。目标函数非连续,IRS的模一约束导致对应的优化问题非凸,对此首先得到了近似问题目标函数的闭式表达式,随后将其解耦为两个子问题:子问题1对应基站波束成形设计,可直接求得闭式解;子问题2对应IRS反射相位设计,该问题依然非凸,采用基于软件无线电的方法获得了该问题的近似最优解。仿真结果表明,基于统计信道信息的传输方案在降低系统开销和算法复杂度的同时能够有效提升IRS辅助的物理层广播系统性能。As a very promising new wireless relay technology,intelligent reflective surface(IRS)can change the wireless transmission environment and effectively improve the spectrum and energy efficiency of wireless systems.This paper proposes an IRS-assisted physical layer broadcast system transmission scheme based on statistical channels.When only statistical channels are known,base station beamforming and IRS reflection phase are jointly designed to maximize the minimum user ergonomic capacity.The objective function is not continuous,and the IRS modulus-constraint leads to the corresponding optimization problem being non-convex.For this,this paper first obtains the approximate closed-form expression of the objective function of the equivalent problem,and then decouples it into two sub-problems,one for each sub-problem.The base station beamforming design can directly obtain a closed-form solution.The second sub-problem corresponds to the IRS reflection phase design.This problem is still non-convex.This paper uses the software defined radio(SDR)-based method to obtain the approximate optimal solution of the problem.The simulation results show that the transmission scheme based on statistical channel information can effectively improve the performance of the physical layer broadcast system assisted by IRS while reducing system overhead and algorithm complexity.

关 键 词：智能反射面 物理层广播 统计信道信息 各态历经容量 软件无线电 

分 类 号：TN929.5[电子电信—通信与信息系统]