| 摘要 |
PURPOSE:To enable to make phase synchronization effectively by regenerating a reference carrier signal when the modulation carrier signal when the modulation carrier signal does not contribute to make a phase error signal removing it by an LPF outputting a clock signal from a gate circuit. CONSTITUTION:An input signal sent from a terminal 13 is orthogonally phase detected by phase detectors 11, 12 and converted to modulation signals P, Q. The signals P, Q are sent to a digital quadruplicating circuit 14, and quadruplicated output S1 and a clock signal CL of a terminal 22 are supplied to a gate circuit 25. When the modulation carrier signal is a signal A which is effective to make the phase error signal, the signal S1 becomes the output of the circuit 25, and if the modulation carrier signal is a signal B that does not contribute to make the phase error signal, the signal CL becomes the output of the circuit 25 by output S2 of a discrimination circuit 21. As the signal CL is removed by an LPF15, reference carrier having small carrier jitter is regenerated. Consequently, phase synchronization can be performed effectively. |
