Selecting highest reliability sync mark in a sync mark window of a spiral servo track crossing

摘要

A method is disclosed for demodulating a spiral servo track recorded on a disk of a disk drive. The spiral servo track comprises a high frequency signal interrupted by a sync mark at a sync mark interval. A demodulation window is enabled relative to a spiral servo track crossing, and a plurality of sync marks are detected in a sync mark window of the demodulation window. A reliability metric is generated for each of the detected sync marks, wherein the reliability metrics are evaluated to select one of the detected sync marks. A clock is synchronized in response to the selected sync mark.