Patent ID: 7333573

Claim:
An automatic frequency control signal generating circuit comprising: a first frequency error detection unit for extracting from an input signal at least two known different symbols as a first symbol set, detecting a first frequency error of said input signal based on said extracted first symbol set, and delivering said first frequency error; a second frequency error detection unit for extracting from said input signal at least two known symbols having a symbol distance different from that of said first symbol set as a second symbol set, detecting a second frequency error of said input signal based on said extracted second symbol set and delivering said second frequency error; a decision unit for deciding which one of the first and second frequency errors of said first and second frequency error detection units is selected; and a control signal unit for generating a control signal adapted to control the frequency of said input signal based on said one of the first and second frequency errors of said first and second frequency error detection units selected by said decision unit.