| 摘要 |
PURPOSE:To realize the pseudo lock prevention circuit of a high performance PSK demodulator. CONSTITUTION:A switch means 15 able to interrupt an input signal to a PSK demodulator 16 is provided on an input stage of the PSK demodulator in the case of the Costas PSK demodulator 16 employed for a receiver. The lock state is detected by a lock detection means detecting the lock state of the PSK demodulator based on an output signal from the PSK demodulator, e.g. by a lock detection means utilizing a synchronization detection means 17 detecting a synchronizing signal from an output signal of the PSK demodulator. Then a controller 19 prevents the receiver from being made stable in the pseudo lock state by applying switching control to the switch means for each prescribed timing for a period when the lock state of the PSK demodulator 16 by the lock detection means is not detected. |
