Patent ID: 6185175
Filing Date: 2001-02-06
Classification: G11B,H04L

Abstract:
A sampled amplitude read channel for reading data recorded on a disk storage medium by detecting an estimated data sequence from a sequence of discrete-time sample values generated by sampling an analog read signal emanating from a read head positioned over the disk storage medium, the sampled amplitude read channel comprising:(a) a sampling device for sampling the analog read signal to generate the discrete-time sample values;(b) a discrete-time equalizer for equalizing the discrete-time sample values according to a desired partial response to generate a sequence of equalized sample values;(c) a discrete-time sequence detector for detecting a preliminary sequence from the equalized sample values; and(d) a post processor for detecting and correcting errors in the preliminary sequence comprising:(i) a remodulator for remodulating the preliminary sequence into a sequence of estimated sample values;(ii) a sample error generator, responsive to the equalized sample values and the estimated sample values for generating a sequence of sample errors;(iii) a sample error filter for filtering the sample errors to generate filtered sample errors;(iv) an error detector, responsive to the filtered sample errors, for detecting errors in the preliminary sequence; and(v) an error corrector, responsive to the error detector, for correcting errors detected in the preliminary sequence,wherein the filtered sample errors are modified to reflect a correction made to the preliminary sequence.