Sensitivity to Doppler shift and carrier frequency errors in OFDM systems-the consequences and solutions

Due to the intercarrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) mobile radio communication systems, the bit error rate (BER) of the received signals are extremely sensitive to Doppler frequency shifts and carrier synchronization errors. This paper studies the mechanism of the ICI signals, and then proposes a new method to overcome such problems without any equalization procedures. The results show that by using the self ICI cancellation scheme proposed, the ICI can be reduced significantly. Therefore this OFDM system suffers much less from performance degradation caused by frequency errors than the normal OFDM systems.