calculated are used in turn by a kalman estimator to record the channel variations on the basis of the sequence of the calculated a posteriori probabilities the detection is then calculated symbol by symbol with the highest a posteriori probability having a small decision delay application_number US 90198197 A description to facilitate reading there are listed below the symbols and terminology used hereinafter l channel pulse response duration measured in multiples of the symbol interval s size of the constellation i e of the total of the values which the transmitted symbols could assume fig1 shows the traditional architecture of an mlse equalizer for varying time channels in which a decoder based on the viterbi algorithm not shown in the figures is supported by a kalman channel estimator estimator using an algorithm which speeds up convergence of the coefficients of an equalizer for fast signal variation channels usually implemented by the standard square root algorithm the large delay d which must be on the order of 5l in order to optimize the performance of the mlse detector is introduced by the mlse decisional procedure and does not permit an accurate estimate of the channel response under fast variation conditions the switch sw periodically switches from position b data detection mode to position a learning mode an improved but not satisfactory version of the traditional diagram is shown in fig2 in which decision attempts with delay d lt lt d are used by the channel estimator while for the final decision there is the usual delay d better results are obtained with equalizers based on the path survival processing psp principle as shown in fig3 their basic structure consists of an mlse detector and s.