| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To accurately detect pilot signals, which are included in playback signals and have a specific frequency, employing a smaller circuit scale. <P>SOLUTION: A playback device is provided with a playback means that reproduces analog signals, into which pilot signals having the specific frequency are superimposed and digital information is included, from a recording medium, an A/D converter which samples the analog signals reproduced by the playback means and converts the analog signals to digital data having a plurality of bits, a delaying means which delays the output of the A/D converter and an adding means which adds the output of the delaying means and the output of the A/D converter, obtains one bit of the most significant digit of the adding result and outputs the bit. Moreover, the playback device is provided with a pilot signal detecting means which detects the pilot signals from one bit data columns that are outputted from the adding means and a tracking control means which controls tracking operations of the reproducing means based on the pilot signals detected by the pilot signal detecting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
