Abstract: The invention relates to apparatus for synchronizing the phase of a digital signal constituted by two digital components to be corrected defining two samples of a received signal at each symbol time, said apparatus serving to feed a regenerator for regenerating the signal in baseband by sampling and threshold decision-taking, said apparatus including: a first phase-locked loop (31) driven by a first broadband phase-error integrator (37), said first loop (31) being fed with the input signal (30) of the apparatus, and supplying a first phase error estimate (36); and an auxiliary second phase-locked structure (32) driven by re-processing means (38) for re-processing said first phase error estimate (36) established by said first phase-locked loop (31), and outputting a phase synchronized signal fed to an output regenerator (34) for regenerating the signal in baseband; said auxiliary second phase-locked structure (32) being fed with said input signal (30) of the apparatus via delay means (35).