Amplitude-based approach for detection and classification of hard-disc defect regions

摘要

In a hard-disc drive, a defect region on the hard disc is classified as corresponding to either thermal asperity (TA) or media defect (MD) by generating two statistical measures. A first measure (e.g., α1) is based on (i) the magnitudes of one or both of signal values (e.g., equalizer input or output signal values) and the corresponding expected values of those signal values and (ii) the signs of one or both of the signal values and the expected signal values. A second measure (e.g., α2) is based on the magnitudes of one or both of the signal values and the expected signal values, but not the signs of either the signal values or the expected signal values. The two measures are then compared to determine whether the defect region corresponds to TA or MD.