An iterative parallel OFDM demodulation for fast time-varying fading channels

This paper proposes a novel OFDM demodulation scheme, which achieves superior performance even in fast time-varying multipath fading channels where the conventional OFDM demodulator degrades seriously because of time selectivity in the channel. The proposed scheme consists of several equalizers which equalize received signals with channel impulse responses at different time instants in parallel. A selector following these equalizers selects the most reliable signal from the outputs of these equalizers. Furthermore, the proposed demodulator employs an inter-carrier interference (ICI) canceler to mitigate degradation due to the time selectivity in the channels. In this paper, two novel ICI cancelers are proposed. Finally, the performance of the proposed OFDM demodulators are verified by means of computer simulation.

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