Low-complexity Doppler compensation in mobile SIMO-OFDM systems

In high-mobility OFDM systems, Doppler distortions cause inter-carrier interference (ICI) that may degrade the system performance severely. Although thoroughly studied, hardly any approaches for ICI estimation and compensation exist that maintain the OFDM-specific subcarrier-wise signal processing and thus provide a solution with reasonable demands on complexity. For a multi-antenna receiver, this paper proposes such an approach which relies on optimum combining of the signals from the different receive antennas. The ICI is characterized in terms of a frequency-selective interference function, which can be estimated by simple means using common pilot signals.