Semi-Blind Channel Estimation in OFDM System

Channel estimation using pilot is common used in OFDM system. The pilot is usually time division multiplexed with the informative sequence. One of main drawbacks is bandwidth losing. In this paper, a new method to perform channel estimation is proposed in OFDM system. The pilot is arithmetically added to the output of OFDM modulator. Receiver uses the hidden pilot to get an accurate estimation of the channel. Then pilot is removed after channel estimation. We also deprive the Cramer-Rao lower bound for this method. The performance of the algorithm is finally shown. Compared with traditional methods, the proposed algorithm increases the bandwidth efficiency dramatically.