Research on Blind Inter-Carrier Interference cancellation and Synchronization Method in OFDM Systems

With regard to the inter-carrier interference (ICI) problem of orthogonal frequency division multiplexing (OFDM) systems due to the carrier frequency offset (CFO), Independent component analysis (ICA) based carrier frequency synchronization method is proposed. This algorithm achieves carrier synchronization directly. The CFO estimation based on pilot sequence and the performance loss due to imperfect CFO estimation can be avoided. In this paper, we first build an analogous ICA model for OFDM systems with the CFO. Then the cost function is obtained from the maximum likelihood (ML) principle. Next, the source symbol recovery is acquired by nature gradient for the purpose of carrier frequency synchronization.Theoretical analysis shows that the ICA-based carrier frequency synchronization method not only has maximum likelihood (ML) source recovery ability based CFO compensation, but also can improve signal to noise ratio (SNR) of OFDM systems. At last, simulation analysis verifies the effectiveness of the proposed algorithm.