Patent ID: 7409029

Claim:
A transmission device performing a signal regeneration control, comprising: a clock timing extraction circuit dynamically setting a frequency-dividing ratio based on a transmission rate of an input signal to perform a phase synchronization control so that the input signal and an oscillation output have a constant phase difference and extracting a clock timing based on the transmission rate; and a regeneration control circuit sequentially sweeping a voltage threshold level and a phase of an extracted clock with respect to the input signal to determine whether signal logic levels measured at adjacent monitor points match with each other and to automatically measure a decision point within a valid zone of an eye pattern at which there is the least possibility that error occurs and performing the regeneration control by using the decision point as an optimal point, wherein the regeneration control circuit performs said sweeping of the voltage threshold level and the phase of the extracted clock at intervals X in units of seconds determined from a relationship of 1/10 n =C/X, where the target error rate is 10 −n , and C is a cycle period of the input signal in units of seconds.