An intercarrier interference cancellation method based on cyclic embedding for OFDM communication systems

Abstract

For orthogonal frequency-division multiplexing (OFDM) communication systems, the frequency offsets in mobile radio channels distort the orthogonality between subcarriers resulting in intercarrier interference (ICI), which seriously degrades the performance of systems. Based on ICI coefficients analysis and reasonable estimation on the frequency offset, this paper presents a novel decorrelation interference cancellation method with the use of frequency-domain equalization at the receiver. Compared with convention frequency-domain equalization, without of iterative operation on weighting coefficients and the inverse operation of matrix, ICI can be eliminated by directly using of cyclic embedding algorithm of Toeplitz matrix in term of discrete Fourier transform (DFT), this new scheme has better convergence reliability and lower computational complexity. Simulation results show that OFDM system using the proposed ICI cancellation scheme can effectively eliminate ICI, have significant performance improvement and mitigate the floor effect of OFDM communication system. This scheme works very well in the multipath radio channel and high-speed mobile environment.