Blind spatio-temporal decision feedback equalization: a self-adaptive approach

It is well known that the performance of any receiver can be improved by means of equalization and diversity combining. However, the problem of blind adaptation is entirely open for a decision feedback equalizer. This paper attempts to introduce a new scheme of blind spatio-temporal equalizer whose main feature is its ability to self-adapt both its structure and its criteria according to the channel severity. Simulation results are given for a 4-QAM signal and compared to those of the classical constant modulus algorithm (CMA) spatio-temporal equalizer. The results are really convincing : the new equalizer exhibits very good performances in terms of the mean square error, bit error rate as well as the convergence speed. From all these points of view, it largely outperforms the classical CMA linear equalizer. As a result, this new blind spatio-temporal equalizer turns out to be very attractive for many applications.