Efficient frequency synchronization and channel estimation method for OFDM wireless systems

Very efficient and robust frequency synchronization and channel estimation method based on pilot tone usage, for OFDM systems in the case of slow time varying channels is proposed. The presented method uses preamble consisting of just one OFDM symbol, for channel and frequency offset estimation and additional two pilot tones embedded in each data symbol, for the neutralization of the cumulative effect of frequency offset in the slow time varying channels. This method enables accurate estimation and correction of all frequency offset values, even those larger than subcarrier spacing. Simulation results show that OFDM system with the proposed frequency synchronization method keeps the BER performance close to the performance of the ideally synchronized system.