| 摘要 |
PURPOSE:To shorten the time taken till establishment of synchronism with another input signal to be next received after a break of an input signal. CONSTITUTION:This demodulator consists on an up/down counter 24 which counts up/down in accordance with the phase detection signal from a phase detector 21, an adding/subtracting part 25 which adds/subtracts the value (DELTAF1 or DELTAF2) of a synchronism pulling-in band to/from the counted output, a counter stop part 31 which monitors a reproduced carrier wave synchronous detection signal INIT and immediately freezes the counted output of the counter 24 at the time of detecting a break of the input signal, and a synchronism pulling-in band setting part 32 for DELTAF2 which extends the synchronism pulling-in band simultaneously. |
