| 摘要 |
<p>PURPOSE: To highly accurately execute tracking at high speed by changing a target tracking value, detecting a maximum point of a reproduced output, and adding a correction for a delay time of a servo system to the maximum point, thereby setting a tracking value. CONSTITUTION: A tracking value generator 5, while incrementing a target value for tracking servo per one rotation of a head drum, outputs the value to a servo circuit 7 thereby to control a capstan motor to achieve the target value. At this time, a delay correction generator 6 obtains a response delay of a system generated to the incrementing rate of the target value and a delay time of a detecting system beforehand, and sends a correcting tracking value to the tracking value generator 5. A neural network 4 detects a maximum point and a minimum point of outputs of an envelope detector 2 and feeds to the tracking value generator 5. Accordingly, the tracking value is changed at a higher speed than a response speed of a servo system, so that the maximum point is obtained quickly. At the same time, influences by noises are reduced, and a tracking accuracy is improved.</p> |
