Improved ICI estimation for mobile OFDM systems

To combat Inter-Carrier Interference (ICI) in mobile OFDM systems, ICI can be reconstructed and removed from the received signal with the aid of channel estimation and decision-feedback. Successful ICI cancellation hinges on accurate channel estimation, which includes both the channel gains and ICI gains, the multiplicative coefficients to the neighbor subcarrier signals representing their power leakage. The channel estimation methods based on the statistical property of the ICI gains were previously proposed by the authors. In this paper, we propose improved ICI gain estimation scheme exploiting the sparse property of the multipath fading channels. The scaling relationship between ICI gain vectors is also further exploited to significantly improve the performance of ICI gain estimation.