Simplified channel estimation method for OFDM systems in fast fading channels

In frequency-selective fast fading channels, large Doppler spread and multi-path interference can reduce the precision of channel estimation seriously. We develop a channel estimation method for orthogonal frequency division multiplexing (OFDM) systems based on Kalman filter and pilot tracking. The low-dimensional Kalman-filter estimator greatly reduces the complexity of the high-dimensional Kalman filter. We implement least square (LS) estimator to track variable channel fading factor a. The simulation results in the frequency band of 5.5 GHz show that the proposed method achieves a good performance close to the theoretic bound of ideal channel estimation.