基于傅立叶变换的OFDM信道估计方法研究  

DFT based channel estimation methods for OFDM

作　　者：张伟[1] 陈前斌[1] 张天骐[1] 邝育军[1] 

机构地区：[1]重庆邮电大学光互联网与无线信息网络研究中心,重庆400065

出　　处：《重庆邮电大学学报（自然科学版）》2007年第4期472-476,498,共6页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：重庆市教委自然科学基金项目(KJ060509);重庆邮电大学科研基金项目(A2006-04)

摘　　要：分析了无线OFDM系统中基于傅立叶变换的信道估计方法,提出了在低信噪比情况下使用LMMSE估计的一种改进方法和在高信噪比情况下使用不需要先验信息的LS估计的改进方法。仿真结果表明,在无线多径慢衰落信道条件下,该改进方法都能够有效对抗频率选择性和先验信息的估计偏差对信道估计的影响,在估计性能与算法复杂度之间取得良好折衷。The DFT based channel estimation algorithms in orthogonal frequency division multiplexing （OFDM） systems is analyzed, and two modified DFT-based methods are proposed to estimate the frequency selective wireless channel.. One method used the modified minimum mean square channel estimation method or a modified least square estimation method at low SNR, and the other used the modified least square channel estimation method without prior information at high SNR. The simulation results show that the proposed methods can withstand the frequency selectivity at slow fading wireless channel and the estimation error of prior information needed in receiver, and the modified methods behave favourably at both channel estimation performance and computation complexity.

关 键 词：正交频分复用 信道估计 最小二乘估计 最小均方差估计 

分 类 号：TN929.5[电子电信—通信与信息系统]