Intercarrier interference cancellation in OFDM mobile systems

Orthogonal frequency division multiplexing (OFDM) is the projected modulation of choice for fourth-generation broadband multimedia wireless systems. However, for mobile applications, channel variations during one OFDM symbol introduce intercarrier interference (ICI), which degrades the performance. This gets more severe as mobile speed, carrier frequency or OFDM symbol duration increases. We analyze ICI for mobile OFDM systems in terms of the complex weighting coefficients, which give the contribution of each transmitter subcarrier to each demodulated subcarrier. Then, we propose a new cancellation method to reduce the effects of Doppler frequency shift. The results show that by using the proposed cancellation scheme, the ICI can be reduced significantly.