OFDM快速频偏估计方法  

Fast frequency offset estimation method for OFDM

作　　者：丁铭[1] 罗汉文[1] 吴赟[1] 徐余法[2] 

机构地区：[1]上海交通大学电子工程系,上海200240 [2]上海电机学院,上海200110

出　　处：《哈尔滨工业大学学报》2009年第9期91-95,共5页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金资助项目(60572157)

摘　　要：提出一种基于前导符号为L等分结构的OFDM快速频偏估计的新方法,该方法只需一个OFDM符号作为前导符号,数据开销较小.接收端先用相关求相角的方法完成细频偏估计,再对经过细频偏补偿后的前导数据进行符号重构,然后对重构符号采用L点FFT运算,通过寻找频域信号峰值,对剩余频偏进行估计,从而完成粗频偏估计.为进一步降低系统的计算开销,采用了多级判决方式.计算机仿真表明,该方案具有计算复杂度低,估计性能较高的优点.A low-overhead oriented method for fast frequency offset estimation of OFDM is proposed, which uses only one OFDM symbot with L identical parts as preamble. By extracting the phase from correlation between two identical halves of the preamble, the fine estimation of frequency offset is obtained and then compensated. After reshaping the compensated preamble into many sub-symbols, L-point FFT algorithm is applied to these sub-symbols. Then, the coarse estimation of frequency offset is achieved by finding the maximum magnitude of resulting frequency domain signals. To further reduce the computational load of the system, the scheme is carried out by means of multistage estimation. Computer simulations show that the proposed method exhibits good estimation performance with low computational complexity.

关 键 词：正交频分复用 频偏 估计 符号重构 前导符号 

分 类 号：TN929.5[电子电信—通信与信息系统]