基于大尺度衰落系数的联合用户分组和导频分配策略  

Joint User Grouping and Pilot Allocation Strategy Based on Large-Scale Fading Coefficients

作　　者：周围[1] 唐俊 马茂琼[2,3] 陈星宇 ZHOU Wei;TANG Jun;MA Maoqiong;CHEN Xingyu(School of Optoelectronic Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China;School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China;Chongqing Key Laboratory of Mobile Communications Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学光电工程学院,重庆400065 [2]重庆邮电大学通信与信息工程学院,重庆400065 [3]重庆邮电大学移动通信技术重庆市重点实验室,重庆400065

出　　处：《计算机工程》2022年第3期124-130,共7页Computer Engineering

基　　金：国家自然科学基金面上项目(61771085);重庆市基础与前沿研究计划项目(cstc2015jcyjA40040)。

摘　　要：导频长度受限会导致相同的导频复用给不同的小区用户,由此引起导频污染问题。导频污染将使得信道状态信息估计不准,从而降低系统性能。针对小区内不同区域用户遭受导频污染程度不同的问题,分析图着色和部分导频交替复用(AFPR)2种导频分配方案,在这2种方案的基础上进行折中,提出一种基于大尺度衰落系数的联合用户分组以及导频分配方案。对用户与本基站之间的大尺度衰落系数大小进行升序排序,将所有小区用户根据所受导频污染严重程度的不同,依次分类为安全边缘用户、危险边缘用户和中心用户,对于安全边缘用户和非安全边缘用户,分别采用加权图着色方案和AFPR方案进行导频分配。仿真结果表明,相比原有AFPR方案,该方案的用户平均上行可达和速率提高约2.2%,其能够有效利用不同区域用户信道质量的差异性来完成导频分配,并通过具有较低复杂度的策略降低导频污染对用户的影响。The limited pilot length causes the same pilot to be multiplexed to different cell users,resulting in pilot pollution,which in turn leads to inaccurate estimation of Channel State Information(CSI),reducing the system performance. To address the problem that users in different areas in the cell suffer from different degrees of pilot pollution,two pilot allocation schemes,graph coloring and Alternately Fraction Pilot Reuse(AFPR),are analyzed. A joint user grouping and pilot allocation scheme based on large-scale fading coefficient is proposed,employing these two schemes. The large-scale fading coefficients between users and the Base Station(BS)are sorted in ascending order to classify cell users into secure edge users,dangerous edge users,and central users according to the severity of pilot pollution. For secure edge and non-secure edge users,Weighted Graph Coloring(WGC)scheme and AFPR scheme are used for pilot allocation,respectively.Simulation results show that compared with the original AFPR scheme,the average uplink sum-rate of users in this scheme are increased by about 2.2%,it can effectively use the differences of user channel quality in different regions to complete pilot allocation,and reduce the impact of pilot pollution on users through strategies with lower complexity.

关 键 词：导频污染 部分导频交替复用 大尺度衰落系数 用户分组 安全边缘用户 非安全边缘用户 导频分配 

分 类 号：TN92[电子电信—通信与信息系统]