A Suppression Scheme of the ICI Caused by Frequency Offset Using the General Correlative Coding in OFDM Systems

The carrier frequency offset (CFO) destroys the orthogonality among subcarriers in orthogonal frequency division multiplexing (OFDM) systems and creates the intercarrier interference (ICI), which results in performance degradation. In this paper, the general correlative coding (GCC) is used to reduce the effect of the ICI caused by the CFO. The expression of the ICI power with GCC is derived and the optimum coefficients of the GCC are obtained based on the minimization of the ICI power. The maximum reduction rate in the ICI power is obtained with respect to the GCC coefficients length from the lower bound of the minimum ICI power and it is shown that the ICI power decreases as the GCC coefficients length increases, leading to CIR improvement. The simulation results show that the general correlative coded OFDM (GCC-OFDM) systems obviously reduces the ICI power without decreasing the bandwidth efficiency