An efficient low complexity cluster-based MLSE equalizer for frequency-selective fading channels

Recently, a novel MLSE equalizer was reported, that does not require the explicit estimation of the channel impulse response. Instead, it utilizes, in an efficient manner, the estimates of the centers of the clusters formed by the received observations. In this paper, a novel cluster tracking scheme is presented, which extends the application of this equalizer in time-varying transmission environments. The proposed algorithm is shown to be equivalent in tracking performance with the classic LMS-based MLSE equalizer, yet much simpler computationally. This is a consequence of the fact that the new method allows for an efficient exploitation of the symmetries underlying the signaling scheme.