Patent ID: 8654621

Claim:
A data recovery method executed by a digital signal processing circuit for receiving a plurality of sampling values from a timing recovery unit of a read channel of an optical storage system, the data recovery method comprising steps of: classifying the plurality of sampling values into a first group, a second group, a third group and a fourth group; generating a first channel estimation value according to the sampling values of the second group, and generating a second channel estimation value according to the sampling values of the third group; and judging whether a first sampling value of the first group is lower than the first channel estimation value or a second sampling value of the fourth group is higher than the second channel estimation value, wherein if the first sampling value of the first group is lower than the first channel estimation value or the second sampling value of the fourth group is higher than the second channel estimation value, a polarity of the first sampling value or the second sampling value is changed and then the plurality of sampling values are outputted, wherein if the first sampling value of the first group is higher than or equal to the first channel estimation value or the second sampling value of the fourth group is lower than or equal to the second channel estimation value, the plurality of sampling values are directly outputted.