In the decoding device which runs maximum likelihood decoding on the basis of with the amplitude and amplitude

摘要

PROBLEM TO BE SOLVED: To determine a highly reliable value indicating signal quality in accordance with the purpose of use.;SOLUTION: An optical disk drive 1 is provided with a viterbi encoder 10 to perform viterbi decoding, and a viterbi decoder 10 is provided with a CHQ calculation part 20 to calculate channel quality. In addition to an amplitude reference value and a reproduction signal for calculating CHQ, a select signal indicating a state of the reproducing signal is inputted to the CHQ calculation part 20. The CHQ calculation part 20 determines a CHQ for each amplitude reference value on the basis of this select signal and registers each CHQ in a dedicated register.;COPYRIGHT: (C)2004,JPO