一种改进的OFDM联合时间频率快速同步算法  

An Improved Joint Timing and Frequency Fast-synchronization-method for OFDM

作　　者：田野 谈振辉[1] 朱刚[1] 

机构地区：[1]北京交通大学轨道交通控制与安全国家重点实验室,北京100044

出　　处：《铁道学报》2007年第4期52-56,共5页Journal of the China Railway Society

基　　金：国家自然科学基金资助项目(60332020);国家自然科学基金重大研究计划项目(90104016)

摘　　要：对文献[9]和文献[10]的算法进行修改,提出一种改进的OFDM联合时间频率快速同步算法,通过使用1个OFDM符号长度的训练符号,可以很好地完成OFDM通信系统的同步。接收端首先通过搜索1个特殊的训练符号,计算出定时同步位置和小数频偏。然后对训练符号的样点数据进行小数频偏补偿和FFT变换,再估算出整数频偏,通过定量分析得出结论,当整数频偏大于7个子载波间隔时,改进的算法具有更快的同步速度。仿真结果表明,改进的算法具有更小的频偏估计方差。This paper presents a new joint timing and frequency synchronization method for OFDM as a modification of the algorithms presented by Paper[9] and Paper[10]. By using only one training sequence, the presented method can perfectly realize the synchronization task. Firstly, by searching for a special training sequence, the receiver calculates the timing position and the decimal frequency offset. Then, after the compensation for the decimal frequency offset and the FFT transform of the training sequence, the integral frequency offset can be estimated. When the integral frequency offset is larger than seven sub-carrier spacings, the synchronization speed of the proposed method is greater. Simulation results show that the proposed method can give out smaller frequency estimation variance.

关 键 词：OFDM 定时同步 训练符号 频偏 

分 类 号：TN914.51[电子电信—通信与信息系统]