Disk drive employing adaptive read/write channel for optimizing head-media-channel performance

摘要

Adaptive channel optimization in a disk drive is achieved by selecting a track of the recording medium and then writing a first data pattern to opposite sides of the selected track. The first data pattern is written a certain percentage off-track in relation to the centerline of the selected track. A second data pattern is then written directly on the selected data track and the off-track margin is determined as a function of how far the recording head can be positioned away from the center of the selected track during reading of the second data pattern while meeting a specified error rate. The off-track margin test is repeated iteratively using a combination of channel variable settings in order to find a set of variable settings which provides an optimal performance criterion for the drive.