A pilot-based frequency offset tracking scheme in OFDM systems

In this paper, a new carrier frequency offset detection scheme is introduced. Compared to previously proposed schemes that utilize the phase offset due to carrier frequency offset, this new scheme utilizes the change of amplitude of received signal by transmitting a pilot symbol through the channel. To enhance the amplitude variation due to carrier frequency offset, a special pilot pattern is designed. The performance of this proposed scheme is investigated with computer simulation and compared with existing amplitude-detect scheme in both additive white Gaussian noise (AWGN) and multipath channels. In both cases, significant performance gain over the conventional amplitude-detect scheme is observed. This proposed scheme is suitable to be used to track the carrier frequency offset.