A novel method of frequency-offset estimation using time domain PN sequences in OFDM systems

In some OFDM systems, time domain cyclic pseudo-random (PN) sequences are inserted between OFDM symbols. This paper proposes a frequency-offset estimation method utilizing the good correlation property of such PN sequences. By combining three levels of estimations, which have different precisions and ranges, the proposed scheme can achieve accurate frequency estimation under different channel environment. Simulation results show that this approach performs well in both AWGN channels and multipath channels.