An inter-carrier interference suppression scheme for OFDM systems in time-varying fading channels

Abstract

Time variations of doubly-selective channels lead to the loss of orthogonality among subcarriers, resulting in inter-carrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) systems. Many schemes have been proposed to suppress ICI, but they are computationally complex or at the price of sacrificing bandwidth. In this paper, we provide an ICI analysis in time domain while existing literatures analyze the ICI effects mainly in frequency domain. Basing on this analysis, we propose a time-domain ICI mitigation method whose complexity is linear in the OFDM symbol length. The method does not reduce any redundancy, and thus has high bandwidth efficiency. Theoretical analysis and simulation results indicate that the proposed method can effectively mitigate ICI with low complexity.