Blind channel estimation for OFDM systems

AbstmctA novel approach of blind channel estimation for OFDM systems is proposed. The information bearing blocks are preprocessed by a mimple linear preeading scheme, which does not introduce redundancy to the block, nor it changes the block length. The precoding imposes a correlation structure on the transmitted blocks, which Ebe exploited at the receiver to r e cover the channel via a computationally simpla cross-correlation procedure. For the Eof BPSK signal the channel estimation is possible based on a single black, while for high-order constellations a small lynount of averaging over successive blocks is required. The performance of the proposed approach b tested analytically, thmugh a mean-square error analysis, and also via simulations. Our resulta suggest that, at low SNR. our blind e_ timstion perform better that channel Bstimation based on training data.