| 摘要 |
PURPOSE:To shorten a synchronism acquisition time without indicating synchronism misacquisition nor enlarging the device by providing a specific cyclic integration control part. CONSTITUTION:An input signal is inputted to a sliding correlation part 5 and multiplied through a multiplier 3 by a dummy noise signal which is outputted from a dummy noise signal generation part 2 and has a phase difference from the input signal, and then the result is integrated by an integration circuit 4. Those outputs are read by the cyclic integration control part 21 to calculate the spread of all phase differences, and such a minimum frequency M' of cyclic integration that the spread of subsequent cyclic integration outputs is in a specific range is calculated on the basis of the calculated spread and sent to a cyclic integrator 8. The output of a correlation part 5 is integrated M' times by the integrator 8 and an acquisition control part 9 sends an acquisition completion signal and a synchronism end signal to a synchronism tracking part 10 according to the M'-time integration output. The synchronism tracking part 10 demodulates the data by a data demodulation part 11 and outputs the demodulated data over synchronism tracking while controlling the phase of the dummy noise signal from a dummy noise signal part 2. |
