导频序列长度对多用户大规模MIMO FDD系统速率的性能影响及优化  

Effects and optimization of pilot sequence length on rate in multiuser massive MIMO FDD system

作　　者：王毅 马鹏阁 黄开枝[2] 李春国[3] 黄永明[3] 杨绿溪[3] WANG Yi;MA Pengge;HUANG Kaizhi;LI Chunguo;HUANG Yongming;YANG Lyuxi(School of Electronics and Communication Engineering,Zhengzhou University of Aeronautics,Zhengzhou 450046,China;National Digital Switching System Engineering and Technological Research Center,Zhengzhou 450002,China;School of Information Science and Engineering,Southeast University,Nanjing 210096,China)

机构地区：[1]郑州航空工业管理学院电子通信工程学院,河南郑州450046 [2]国家数字交换系统工程技术研究中心,河南郑州450002 [3]东南大学信息科学与工程学院,江苏南京210096

出　　处：《通信学报》2018年第7期92-102,共11页Journal on Communications

基　　金：国家自然科学基金资助项目(No.61372101;No.61671144;No.61701538;No.U1404615);中央军委十三五预研基金资助项目(No.6140311030207);中国博士后科学基金资助项目(No.2018M633733);河南省高校科技创新团队支持计划基金资助项目(No.17IRTSTHN014);河南省科技攻关计划基金资助项目(No.182102210449);河南省高等学校重点科研基金资助项目(No.19A510024);江苏省高校自然科学研究面上项目(No.16KJB510008)~~

摘　　要：针对多用户大规模MIMO FDD下行链路系统,分析了导频序列长度随基站天线数变化时对系统下行遍历速率的渐进性能影响。利用确定性等价原理,推导出遍历速率的解析表达式,基于此分析得出:归一化导频开销(导频序列长度与天线数之比)趋近于0时,仍可满足传输速率随基站天线数增加而无限增加;固定导频序列长度而只增加基站天线数,系统传输速率将出现饱和效应。进一步地,在有限的信道相干时间内,以系统和速率最大化为目标来优化导频序列长度,并在特殊相关信道模型下,借助于Lambert W函数,推导最优导频序列长度的闭式解。仿真结果验证了理论分析的正确性和最优导频序列闭合解的有效性。The effect of pilot sequence length on the asymptotic performance of the ergodic rate was investigated for the multiuser massive multiple-input multiple-output(MIMO)frequency division duplexing(FDD)downlink system.Firstly,the analytical expression of the ergodic rate was derived by using the principle of deterministic equivalence,based on which,it was discovered from the analytical results in two-fold that the normalized pilot sequence length(defined as the pilot sequence length divided by the number of BS antennas)tends to zero yet the rate was guaranteed to grow large without limit as long as the BS antenna number continues to increase,the rate saturates to a certain level if the BS antenna number becomes large with fixed pilot sequence length.Moreover,the pilot sequence length was optimized based on the sum-rate maximization within a finite channel coherence time,and a closed-form solution was deduced under a special correlated channel by means of Lambert W function.Simulation results validate the correctness of the theoretical analysis results and verify the effectiveness of the proposed closed-form solution of the optimal pilot sequence length.

关 键 词：大规模多输入多输出 频分双工 导频序列长度 下行速率 渐进性能 

分 类 号：TN92[电子电信—通信与信息系统]