一种改进OFDM定时同步算法

摘要

最大似然算法即ML算法的计算复杂度低,且其以循环前缀与OFDM最后一部分符号的相关性进行OFDM同步估计,节省了系统的带宽资源,因而,ML算法是OFDM同步算法中很经典的算法之一.为改善ML算法在低信噪比时的同步性能,提出了一种新的OFDM同步算法.该算法对ML算法的定时测度函数进行改进,所得的新算法不仅保留了原ML算法的优势,且改善了原ML算法在低信噪比下的均值误差和均方误差.%Maximum likelihood algorithm ( ML algorithm) has low computational complexity,and it implements OFDM synchronization estimation by the correlation between cyclic prefix and the last part symbols of OFDM,which saves the bandwidth resource of the system.So ML algorithm is one of classical OFDM synchronization algorithms.A novel algorithm is proposed by improving the timing metric function of ML algorithm.The proposed method has the advantages of ML algorithm and improves the mean error and MSE of ML algorithm at low SNR.