A servo compensation processor includes an input that receives samples of a waveform generated from a servo track, the servo track including servo data and synchronization symbols. A peak estimator estimates a first location of a peak amplitude of the waveform. A phase determiner determines a sampling...http://www.google.com.hk/patents/US7715134?utm_source=gb-gplus-share專利 US7715134 - Demodulation compensation for spiral servo tracks in hard disk drives
