单通道记录信号的OFDM系统频偏估计新方法

New Method of OFDM Carrier Frequency Offset Estimation Using Single Channel Recordings

提出了一种利用独立分量分析(ICA)技术估计正交频分复用(OFDM)系统频偏的新方法.传统的ICA算法进行频偏估计需要通过不同手段获得多路混合信号,该方法只需利用相关检测技术处理单路OFDM信号,获得观测信号向量,通过ICA算法分离出含频偏信息的信号,然后估计OFDM系统的频偏.与传统的频偏估计方法相比较,该方法不需要信道状态信息(CSI)和辅助信息,不需要额外的带宽,大大降低了系统实现的复杂度,因此具有一定的优越性.仿真结果表明,该方法频偏估计准确度较高,估计范围可以达到±0.5倍的子载波间隔.

This paper proposes a novel approach to estimate carrier frequency offset（CFO）of an OFDM system using independent component analysis（ICA）.Classical ICA algorithms require multiple mixed signals to perform signal separation.However,only by processing single channel OFDM data with the correlation detection technology,the new method is capable of separating the independent components,which include CFO information using ICA and then estimate the CFO of OFDM signals.Compared with the traditional frequency offset estimation methods,this method requires no channel state information（CSI）,auxiliary information,and additional bandwidth,thus greatly reducing the complexity of system implementation.The simulation results show that the method is accurate and its range of frequency offset estimation can reach 0.5times of the sub-carrier spacing.