| 摘要 |
PURPOSE:To detect a synchronizing signal with no effect of error by obtaining the auto-correlation with a prescribed one of digital signals for detection of the synchronizing signal in response to the characteristics of errors caused when the information is read and detecting the value larger than a prescribed level for said auto-correlation. CONSTITUTION:A decoder 1 takes notice of only the part ''1'' of a synchronizing signal pattern to obtain an auto-correlation; while a decoder 2 takes notice of only the part ''0'' of said signal pattern to obtain the auto-correlation respectively. Then an OR is obtained between both correlations by an OR circuit 5 through peak detectors 3 and 4. Thus a synchronizing signal can be detected despite an extra error or a missing error. As a result, both extra and missing errors never arise at a time within a synchronizing signal. Therefore a synchronizing signal detector can have the assured synchronization. |
