Patent ID: 6904084
Filing Date: 2005-06-07
Classification: G11B,H04L

Abstract:
1. A read channel apparatus for reading data recorded on an optical storage system at a predetermined baud rate, comprising: a sampling device for asynchronously sampling an analog read signal generating from the optical storage system to generate a sequence of asynchronous sample values; a subtractor for subtracting an estimated DC offset from the asynchronous sample values to generate a sequence of asynchronous DC-removed sample values; a first interpolator for interpolating the asynchronous DC-removed sample values to generate a sequence of synchronous even-time sample values substantially synchronized to one-half the baud rate; a second interpolator for interpolating the asynchronous DC-removed sample values to generate a sequence of synchronous odd-time sample values substantially synchronized to one-half the baud rate; a first equalizer for equalizing the synchronous even-time sample values in accordance with a target spectrum to generate a sequence of even-time equalized sample values; a second equalizer for equalizing the synchronous odd-time sample values in accordance with the target spectrum to generate a sequence of odd-time equalized sample values; a timing recovery controller, responsive to the even-time equalized sample values and the odd-time equalized sample values, for controlling the first interpolator and the second interpolator respectively in order to synchronize the even-time and odd-time sample values to the baud rate; and a DC offset estimator for generating the estimated DC offset from the even-time equalized sample values and the odd-time equalized sample values; wherein the recorded data are determined from the even-time equalized sample values and the odd-time equalized sample values.