多径衰落信道下OFDM系统的符号同步方法研究  

Research on OFDM Systems About Symbol Synchronization Method over Multipath Fading Channels

作　　者：高亮[1] 谢健[1] 

机构地区：[1]湖南大学信息科学与工程学院,湖南长沙410082

出　　处：《计算技术与自动化》2014年第4期64-67,共4页Computing Technology and Automation

基　　金：国家科技支撑计划项目(2013BAH45F02)

摘　　要：由于在正交频分复用(OFDM)的系统中存在符号时间同步误差,为了消除这种误差,提出了工作在多径衰落信道的符号时间频移(STO)估计方法,即基于CP的符号时间偏移估计和基于训练符号的符号时间偏移估计,通过仿真对基于循环序列(CP)估计技术的最大似然法(ML)和基于训练符号的最小均方差异法(Classen)两类性能比较分析,在无载波频移条件下,ML算法精确度更高,当存在载波频移时,Classen算法精确度更高。Because of the orthogonal frequency division multiplexing （OFDM） symbol time synchronization error in the system, in order to eliminate the error, estimation techniques for symbol time offset over multipath fading channels was pro- posed, the symbol timing offset estimation based on CP and based on training symbols to estimate symbol timing offset, through the analysis and comparison with the maximum-likelihood estimation（ML）scheme, which the scheme are using the Cyclic Prefix（CP） technique and the minimizing the squared difference （Classen）, which the scheme are using the Training Symbol technique, the simulation results that the ML estimation have higher accuracy, when there is no carrier frequency offset（CFO） ,and when the CFO is exist, the Classen estimation have higher accuracy.

关 键 词：正交频分复用 符号时间频移 循环序列 符号间干扰 

分 类 号：TN914[电子电信—通信与信息系统]