Extended Kalman Filter for Channel and Carrier Frequency Offset Estimation

In this paper, the algorithms of combining channel estimation with CFO estimation are studied for mobile OFDM system. The comb-type pilot is used for channel estimation. There are some known algorithms for channel estimation such as LS (Least Square), Minimum Mean Square Error (MMSE), some adaptive estimators such as Kalman Filter, Extended Kalman Filter ... To enhance performance, we modified the algorithm of channel estimation by jointly estimating the channel frequency response and CFO (Channel Frequency Offset) from the transmission of known pilot symbols. This new estimator had good performance in fading environments for vehicular model with high mobile speed. Bit Error Rate (BER) performance of the proposed algorithm is verified by computer simulation.