Patent ID: 7460593

Claim:
A signal processing device for processing a received signal to generate a sliced signal, comprising: an equalizer for generating an equalized signal according to the received signal; a multilevel quantizer, coupled to the equalizer, for utilizing X threshold/thresholds to quantize the equalized signal to thereby output the sliced signal being one of at least X+1 predetermined levels when a first mode is adopted, and utilizing Y thresholds to quantize the equalized signal to thereby output the sliced signal being one of at least Y+1 predetermined levels when a second mode is adopted, wherein the X and the Y are positive integers, the Y is more than the X, and the at least Y+1 predetermined levels are more than the at least X+1 predetermined levels; and a control logic for adopting one of the first mode and the second mode by executing the following steps: adopting the first mode and then comparing the equalized signal with the sliced signal which is the one of the at least X+1 predetermined levels for obtaining a first difference and comparing the equalized signal with a predetermined value which is different from any of the sliced signal and the X threshold/thresholds for obtaining a second difference; adopting the second mode instead of the first mode when the first difference and the second difference together indicate an unreliable status; and adopting the first mode when the first difference and the second difference together indicate a reliable status.