Abstract: In high-speed mobile environment, the inter-carrier interference (ICI) caused by the Doppler effect degrades the performance of the orthogonal frequency division multiplexing (OFDM) system. In order to lessen the severe effects of ICI, a novel ICI mitigation algorithm is proposed, which is called the time-domain ICI self-cancellation (TDISC). In this algorithm, the repeated symbol is used at the transmit side, and large numbers of reconstructed OFDM symbols with different additional delays are obtained by some manipulations of the received data, and then diversity combination of these reconstructed OFDM symbols is applied by using the channel statistic property at the receive side, and thus the system performance of ICI suppression is improved. Through simulations and analyses, it is proved that the TDISC can effectively combat the ICI, improve system performance and, consequently, be an effective solution to the implementation of OFDM in high-speed mobile environment.

Key words: orthogonal frequency division multiplexing (OFDM), inter-carrier interference (ICI), time-domain ICI self-cancellation (TDISC), additional delay, channel statistic