Patent ID: 6799296
Filing Date: 2004-09-28
Classification: G11B,H03M

Abstract:
A radix-8 Viterbi detector for use in a signal reproduction apparatus for a high speed optical disk, comprising:a frequency dividing unit for dividing a main clock frequency to generate an auxiliary clock at one-third of the main clock frequency; a branch metric calculation unit for calculating each of a plurality of branch metrics via a predetermined transfer function using data input at the main clock frequency; a serial-to-parallel converting unit for outputting each of the branch metrics calculated by said branch metric calculation unit at the main clock frequency in units of 3 state bits; an addition/comparison/selection unit for adding the branch metrics input from said serial-to-parallel converting unit and previous state metrics stored before the 3 state bits are input and for comparing the addition results to select and output the minimum of the addition results as a new state metric, and for outputting a corresponding path selection signal, at the auxiliary clock frequency; a path memory for storing the path selection signal and for outputting parallel data corresponding to said path selection signal, at the auxiliary clock frequency; and a parallel-to-serial converting unit for converting the parallel data output from said path memory into serial data.