In this paper, we propose a semi-blind channel estimation method based on an Expectation-
Maximization Block algorithm (EM-Block). In the OFDM communication context, such an
algorithm still have a linear arithmetical complexity. However, it yields to an SNR
improvement going up to 3 dB compared to classical training sequences based channel
estimation method in the context of 5 GHz OFDM WLANs. The new algorithm performs better
than already existing recursive algorithms and use much less prior information on the …

In the OFDM communication context, semi-blind algorithms allow to cope with Doppler effect
due to the mobility of wireless systems. For slowly varying channels, the estimation process
can be performed on a block of symbols assuming that the channel is constant over the
block. This algorithm enhances the performance in terms of channel estimation with the
additional advantage of a linear arithmetical complexity. In this paper, we propose an EM-
MAP algorithm which takes into account a channel correlation model between the …