| 摘要 |
<p>PURPOSE:To provide a digital data detector which follows up only variation due to wows and flutters of a digital received signal and detects digital data having a small data error. CONSTITUTION:A point where the digital received signal sampled by an A/D converter 1 crosses a reference level is detected to output a zero-cross point signal C and the predicted value Pi+J' of a current phase is calculated from the predicted value Pdi+1 of a phase interval, etc., calculated from a last phase Pi and a phase Pi-j which is more than two phases ahead; and the band limitation predicted error Y of the current phase which has its frequency band limited by a digital filter circuit 8 is calculated from the current predicted error X calculated by a subtracting circuit 7 and a data detection clock and digital data are detected from the predicted value Pi+1 of the current phase and phase information on the current phase Pi+1, etc., calculated from the band limitation predicted error Y of the current phase corresponding to the zero-cross signal C.</p> |
