Phase error detecting module and phase error detection method

A phase error detection method, comprising:

• generating a constellation point selection signal according to a position and a radius of data of an input signal in a constellation diagram;
• selecting, according to the constellation point selection signal, a part of all of a plurality of constellation points of the constellation diagram, as a plurality of reference constellation points for calculating an estimated symbol corresponding to the data of the input signal, and a quantity of the plurality of reference constellation points is smaller than a quantity of all of the plurality of constellation points;
• and
• calculating an estimated phase error of the input signal according to the data of the input signal and the estimated symbol,
• wherein the constellation diagram is divided into a plurality of areas, and the step of generating the constellation point selection signal according to the position of the data of the input signal in the constellation diagram comprises:
• determining in which one of the plurality of areas the position of the data of the input signal is located in the constellation diagram to generate an area indication signal;
• determining whether the radius of the data of the input signal in the constellation diagram is greater than a radius threshold to generate a radius indication signal;
• and
• generating the constellation point selection signal according to the area indication signal and the radius indication signal.

A phase error detection module, comprising:

• a constellation point selector, generating a constellation point selection signal according to a position and a radius of data of an input signal in a constellation diagram;
• a symbol estimator, selecting, according to the constellation point selection signal, a part of all of a plurality of constellation points of the constellation diagram, as a plurality of reference constellation points for calculating an estimated symbol corresponding to the data of the input signal, and a quantity of the plurality of reference constellation points is smaller than a quantity of all of the plurality of constellation points;
• and
• a phase evaluator, calculating an estimated phase error of the input signal according to the data of the input signal and the estimated symbol,
• wherein the symbol estimator comprises:
• a plurality of multiplexers, selecting the plurality of reference constellation points from all of the plurality of constellation points according to the constellation point selection signal;
• and
• a symbol estimator, generating the estimated symbol by means of a minimum mean squared algorithm based on the plurality of constellation points