Bandwidth adjustment method and associated bandwidth adjustment circuit and phase recovery module

A bandwidth adjustment circuit, for a phase recovery module, comprising:

• a statistics circuit, recording a plurality of phase errors between an input signal that is compensated by the phase recovery module and a reference signal, and calculating a statistical value of the plurality of phase errors to generate a statistical indication signal;
• a control circuit, generating a bandwidth indication signal according to the statistical indication signal, wherein the bandwidth indication signal corresponds to an optimum bandwidth;
• and
• a conversion circuit, generating at least one filter coefficient of a working bandwidth of a phase compensation adjustment circuit in the phase recovery module according to the bandwidth indication signal.

A phase recovery module, comprising:

• a multiplication circuit, multiplying an input signal by a phase compensation signal to generate a compensated input signal;
• a phase error detection circuit, detecting a phase difference between the compensated input signal and a reference clock signal;
• a phase compensation adjustment circuit, generating the phase compensation signal according to the phase difference;
• and
• a bandwidth adjustment circuit, comprising a statistics circuit, a control circuit and a conversion circuit;
• wherein, the bandwidth adjustment circuit obtains an upper bandwidth limit and a lower bandwidth limit according to an initial upper bandwidth limit and an initial lower bandwidth limit, obtains an optimum bandwidth according to the upper bandwidth limit and the lower bandwidth limit, adjusts the initial upper bandwidth limit and the initial lower bandwidth limit according to the optimum bandwidth to obtain an adjusted initial upper bandwidth limit and an adjusted lower bandwidth limit, and adjusts the optimum bandwidth according to the adjusted initial upper bandwidth limit and the adjusted initial lower bandwidth limit.