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Multiple Doppler estimation based ICI elimination scheme in OFDM over high-mobility channels with LoS path

Although Orthogonal Frequency Division Multiplexing (OFDM) is an effective way to combat frequency selective fading of the wireless channel, it is very sensitive to frequency shifts. Doppler spreading due to the mobility of communication terminals or reflectors destroys the orthogonality among the subcarriers, and results in intercarrier interference (ICI). In this paper, we propose a multiple Doppler frequency offsets (DFOs) estimation based scheme to diminish the ICI in an OFDM transceiver for communication between a base station (BS) and a high-speed train. The proposed scheme utilizes a particularly designed preamble to estimate the DFOs by single receiving antenna, and preprocesses the received (downlink) OFDM symbol based on the DFOs estimates so that the post signal-to-interference ratio (SIR) gain can be obtained. Numerical results demonstrate that the proposed scheme can effectively obtain the DFOs estimates and achieve an obvious SIR gain when there exists a strong line-of-sight (LoS) path between the BS and the high-speed train.