APPARATUS FOR REPRODUCING DIGITAL INFORMATION VIA A TRANSMISSION MEDIUM

摘要

An apparatus is described for reproducing digital information from an optically readable disc. In order to measure the phase difference between a channel clock and the intersections of the data signal being read with a decision level, samples on both sides of said intersections are interpolated and the amplitudes of the samples are compared with the decision level. The amplitude difference is a measure of the phase difference.