| 摘要 |
PURPOSE:To eliminate pseudo synchronism of a phase synchronization system for carrier recovery which is included in a demodulating device by providing a voltage-controlled oscillator, a couple of phase detectors, a couple of A-D converters, and a carrier regeneration control means. CONSTITUTION:A phase control signal E is sent to the voltage-controlled oscillator 3, whose oscillation frequency is controlled with a phase control voltage E. The phase synchronization system for carrier regeneration is composed of a code converter 7, a phase error detector 8, the voltage-controlled oscillator 3, and a pi/2 phase shifter 3, but DX and DY, and EX and EY inputted to the phase error detecting circuit 8 correspond to signal points on a phase plane through the reverse conversion logical processing operation of the code converter 7, so a phase control signal E outputted by the phase error detecting circuit 8 is generated as a phase error signal matched with the phase synchronization system and there is no any possibility of the occurrence of pseudo synchronism at all. |
