基于压缩感知的OFDM稀疏信道估计中的导频设计  

Pilot Design for Compressed Sensing Based Sparse Channel Estimation in OFDM Systems

作　　者：李姣军 邱天 蒋扬 左迅 杨凡 LI Jiaojun;QIU Tian;JIANG Yang;ZUO Xun;YANG Fan(School of Electrical and Electronic Engineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学电气与电子工程学院,重庆400054

出　　处：《电讯技术》2022年第2期232-237,共6页Telecommunication Engineering

基　　金：重庆市基础科学与前沿技术研究专项基金资助项目(cstc2019jcyj-msxmX0233)。

摘　　要：为了提高基于压缩感知的正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)稀疏信道估计性能,提出以互相关矩阵元素之间的距离立方和作为新的导频设计准则,更加准确地评价采样矩阵整体互相关性;针对传统导频搜索算法效率慢的问题,提出一种基于树的顺序替换导频间隔搜索(Tree-based Sequential Replacement Pilot Interval Search,TSS)算法,避免了间隔过大和过小的导频入选候选集,优化了导频搜索效率。仿真结果表明,与现有的导频设计方案相比,采用新准则设计的导频能够有效减小约4 dB的信道均方误差。同时,新提出的导频搜索算法复杂度更低,且具有更好的收敛效果。In order to improve the performance of orthogonal frequency division multiplexing(OFDM)sparse channel estimation based on compressed sensing,the sum of the distance cubes between the elements of the cross-correlation matrix is proposed as a new pilot design criterion to more accurately evaluate the overall cross-correlation of the sampling matrix.In addition,in view of the slow efficiency of traditional pilot search methods,a tree-based sequential replacement pilot interval search(TSS)algorithm is proposed,which avoids pilots with too large and small intervals from being selected into the candidate set,and optimizes pilot search efficiency.The simulation results show that,compared with the existing pilot design schemes,the proposed criterion can effectively gain 4 dB improvement in the channel mean square error.Furthermore,the newly proposed pilot search method has lower complexity and better convergence performance.

关 键 词：正交频分复用 稀疏信道估计 压缩感知 导频设计 搜索算法 

分 类 号：TN929.5[电子电信—通信与信息系统]