Patent ID: 7092458

Claim:
A carrier recovery circuit recovering a carrier from an input signal including a mixture of a plurality of PSK modulated signals having different values of M for M-ary encoding, where M is 2 N and N is a positive number, comprising: a first phase detection unit assuming that the input signal is a PSK modulated signal having a minimum M value in detecting a phase error of a recovered carrier; a second phase detection unit assuming that the input signal is a PSK modulated signal having a maximum M value in detecting a phase error of the recovered carrier; a frequency detection unit assuming that the input signal is a PSK modulated signal having a maximum M value in detecting a frequency error of the recovered carrier; a selection unit for selecting one of the phase error detected by said first phase detection unit and the phase error detected by said second phase detection unit; and a carrier recovery unit for recovering the carrier by adjusting a phase of the input signal, based on the phase error selected by said selection unit and the frequency error detected by said frequency detection unit.