摘要：The time variations of the channel during oneOFDM symbol interval destroy the orthogonality of thedifferent subcarriers and generate power leakage amongthe subcarriers, resulting in intercarrier Interference (ICI),which degrades the performance considerably. To mitigatethe effects of channel variations, many schemes havebeen proposed, but they are computationally complex orat the price of sacrificing spectral efficiency. In practicalOFDM systems, some known symbols, such as pilots, willbe transmitted with data symbols simultaneously in thefrequency domain.We find that mitigating the ICI generatedby these signals can be performed efficiently with a lowcomputational complexity, since the transmitted symbolsare known at receiver and no error propagation problemshould be considered. In this paper, we propose a novelpilot cancellation scheme for OFDM systems in time-varyingchannels which is implemented by reconstructing the pilotsignal in the time domain at receiver and subtracting itbefore detecting the data signal. Simulation results show thatthe proposed method performs better than the conventionalmethod in which no pilot cancellation is employed andthe gap becomes larger with the increase of the maximumDoppler frequency.
