Patent ID: 7251274

Claim:
An equalizer device for digital communications systems having a plurality of receive channels, the equalizer device presenting in normal operation a first structure which comprises a first transversal filter for each receive channel, the first transversal filter being connected to summing means for summing the receive channels, and a system downstream from said summing means including a first phase corrector and a first recursive portion including a single recursive filter and decision circuit in its forward branch, said equalizer device including decision-taking means for evaluating its performance as a function of the output signal from said equalizer device and a switch for responding to the result of this evaluation by switching from the first structure which corresponds to a normal mode of operation, also referred to as a tracking mode or an easy reception mode, to a second structure which corresponds to a convergence mode of operation, also referred to as a difficult reception mode, and vice versa, the second structure including a second recursive portion comprising a purely recursive filter in each receive channel, each purely recursive filter being upstream from a second transversal filter in each receive channel, wherein, in the second structure corresponding to the convergence mode, each purely recursive filter of the plurality of receive channels is identical and is adapted for minimizing a cumulated sum of output powers.