| 摘要 |
PURPOSE:To attain multi-stage relay even for a repeater station having logical delay by extracting a serial data string for timing extraction not from the reception end but from the transmission end so as to eliminate the relative phase difference between the extraction clock and a data pattern caused by logic delay. CONSTITUTION:A selector circuit 6 is provided, which selects an input signal to a timing extraction section of the repeater station. Then a signal 13 to start a timing extraction section is given to one input of the selector circuit 6 and the transmission data output 14 of the repeater station is given to the other input of the selector circuit 6. Moreover, a logic processing section 3 uses a monitoring signal 10 of the timing extraction section to control the selection signal of the selector circuit 6 and extracts the timing by using the transmission data output 14 after the timing extraction section is started so as to transmit the data. Thus, accumulation of alignment jitter is eliminated and the data relay system capable of relaying data in multi-stage independently of the presence or absence of logic delay. |
