Patent ID: 8526135
Filing Date: 2013-09-03
Classification: G11B

Abstract:
1. A tracking control method for causing a magnetic head to follow a perpendicular recording-type magnetic tape with a servo signal written therein, in which servo signal a magnetic pattern is repeatedly arranged in a longitudinal direction of the magnetic tape at predetermined intervals, the magnetic pattern being composed of a first portion magnetized in one direction that is one of two opposite thickness directions and a second portion magnetized in a direction opposite to the one direction, the method comprising the steps of: reading out the servo signal and acquiring, from the readout servo signal, a waveform of the servo signal in which a unit waveform having a pair of peaks of opposite polarities corresponding to the magnetic pattern appears periodically, the unit waveform being composed of a crest portion and a trough portion; selecting, from between the crest portion and the trough portion of the unit waveform contained in the acquired waveform of the servo signal, a portion of the waveform containing one of the peaks located rearwardly in a tape transport direction in a time of writing the servo signal; and regulating a position of the magnetic head based on the selected portion of the waveform.