一种OFDM系统中的符号定时同步方法

A Novel Symbol Timing Synchronization Algorithm for Orthogonal Frequency Division Multiplexing

正交频分调制(OFDM)是一种高效的数据传输技术,具有良好的抗频率选择性衰落能力,并且提高了频谱利用率。但是OFDM对同步误差十分敏感,特别是符号同步误差。传统的MLE算法虽对符号定时估计很有效,但在ISI干扰情况下性能不高。针对MLE算法的不足,提出了一个基于新的算法。同时通过Matlab的模拟仿真表明,在信噪比较高时,新的算法定时估计性能优于MLE算法。

The great advantage of OFDM is that it is robust against frequency selective fading and that it improves frequency utilizing rate simultaneously. But OFDM is very sensitive to synchronization error, especially the symbol synchronization error. Traditionally, the MLE algorithm is an effective method of symbol timing estimation, but it has very low performance when there is ISI. In response to the shortcomings of the MLE algorithm, this paper presents a new method. The result of Matlab simulation shows that the timing estimation performance of the new algorithm is better than the MLE algorithm at higher signal to noise ratio(SNR ).