| 摘要 |
PROBLEM TO BE SOLVED: To accurately suppress phase jitters by preventing increase of noise of signals in a phase jitter extraction circuit. SOLUTION: The phase jitter extraction circuit is provided with a phase jitter detection part 4-1 detecting the phase jitter normalized at a prescribed position on a vector plane from input/output information of a signal judging device, a phase jitter prediction part 4-2 predicting the phase jitter to be generated after the phase jitter detected in the phase jitter detection part 4-1, a selector 4-3 selectively outputting the phase jitter or the predicted phase jitter, and a selector control part judging an area of a signal point sent through a transmission line and controlling the selector 4-3 so as to prevent noise increase by the normalized phase jitter from the phase jitter detection part 4-1 on the basis of a judged result. |
