SAMPLING FREQUENCY CONTROL CIRCUIT

摘要

PURPOSE:To converge reproduced sampling frequency information to required accuracy within a short time. CONSTITUTION:An image signal is sent from the transmitting side to the receiving side through a transmission line provided with a prescribed transmission frequency band. On the receiving side, receiving side frequency information is found out from the transmission line frequency and reproduced sampling frequency by the 1st frequency divider 14 and a counter 15 and an error between the transmitting side frequency information and the receiving side frequency information is found out by a subtractor 18 as frequency error information. A deviation between a previously determined convergent value and the frequency error information is found out by a forecasting device 20 and an adder 19 as a deviation value. The frequency error information is corrected in accordance with the deviation value to obtain corrected frequency error information. A voltage control oscillator 16 controls the reproduced sampling frequency in accordance with the corrected frequency error information.