| 摘要 |
PROBLEM TO BE SOLVED: To provide a carrier recovery circuit that discriminates the polarity of detuning frequency. SOLUTION: A TMCC period detection circuit 4 detects the TMCC period from the synchronization detection output of a synchronization detection circuit 1, a signal point arrangement conversion circuit 5 converts a synchronization detection output to a signal point arrangement, a phase rotation circuit 8 rotates the phase of a signal point position signal converted by the signal point arrangement conversion circuit 5 at a predetermined prescribed angular velocity for each TMCC symbol, a phase detector 6 applies phase detection to the signal point position signal whose phase is rotated, an autocorrelation detection circuit 7 obtain an autocorrelation detection circuit 7 obtains the autocorrelation function of a phase detection output for the TMCC period and also angular velocity information based on a period of the autocorrelation function waveform, a subtractor circuit 9 subtracts the phase rotation angular velocity in the phase rotation circuit 8 from the angular velocity information of the autocorrelation detection circuit 7, and a numerically controlled oscillator 2 causes sine wave data and cosine wave data to be generated with a frequency based on the subtraction output and causes them to be given to the synchronization detection circuit 1. |
