RIS辅助的混合RF/THz系统性能分析  

Performance analysis of RIS-assisted mixed RF/THz system

作　　者：黎赛 杨亮 崔琪楣[2] 于思源[3] LI Sai;YANG Liang;CUI Qimei;YU Siyuan(College of Computer Science and Electronic Engineering,Hunan University,Changsha 410082,China;School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China;School of Astronautic,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]湖南大学信息科学与工程学院,湖南长沙410082 [2]北京邮电大学信息与通信工程学院,北京100876 [3]哈尔滨工业大学航天学院,黑龙江哈尔滨150001

出　　处：《通信学报》2022年第1期49-58,共10页Journal on Communications

基　　金：湖南省重点研发计划基金资助项目(No.2022GK2051);湖南省高新技术产业科技创新引领计划基金资助项目(No.2022GK4004);国家自然科学基金资助项目(No.91838302)。

摘　　要：针对太赫兹(THz)链路传输距离短的问题,研究了智能反射表面(RIS)辅助的混合双跳射频(RF)/THz系统的性能。RIS用于增强信号强度,从而提升系统性能。采用固定增益放大转发协议,推导了混合RF/THz链路端到端信噪比的累积分布函数和概率密度函数表达式。利用这些统计特性,进一步推导了该混合中继系统的中断概率、平均误码率和平均信道容量的分析表达式。此外,还对中断概率和平均误码率进行了渐近分析,获得了混合RF/THz系统的分集度。仿真结果表明,RIS可以有效提高混合RF/THz系统的性能。此外,系统的性能还与信道衰落参数、指向误差和距离有关。To solve the problem of the short transmission distance of terahertz(THz)links,the performance of the reconfigurable intelligent surface(RIS)-assisted mixed dual-hop radio frequency(RF)/THz system was studied.An RIS was used to enhance signal strength,thereby improving the system performance.Using the fixed-gain amplify-and-forward protocol,the cumulative distribution function and probability density function of the end-to-end signal-to-noise ratio of the RF/THz link were derived.Capitalizing on the statistical characteristics,the analytical expressions of outage probability,average bit error rate,and average channel capacity of the mixed relaying system were further derived.In addition,the asymptotic analyses of the outage probability and the average bit error rate were carried out to obtain the diversity order of the mixed RF/THz system.Simulation results show that the RIS can effectively improve the performance of the mixed RF/THz system.Furthermore,the system performance is related to the channel fading,pointing errors,and propagation distance.

关 键 词：可重构智能表面 太赫兹通信 混合双跳系统 性能分析 

分 类 号：TN92[电子电信—通信与信息系统]