Patent ID: 7852960

Claim:
A path metric computing unit applied in a Viterbi detector, for generating a first path metric according to a plurality of previous path metrics and a first branch cost, wherein the Viterbi detector receives an input signal, then generates a detecting result based on the input signal, and computes the first branch cost according to at least two input signals corresponding to at least two input timings, the path metric computing unit comprising: a comparator for generating a control signal according to the previous path metrics, wherein the control signal corresponds to the best of the previous path metrics; a first combinational circuit for generating a plurality of first candidate path metrics according to the previous path metrics and the first branch cost; a first multiplexer, electrically connected to the comparator and the first combinational circuit, for determining the first path metric according to the control signal and the first candidate path metrics; a second combinational circuit for generating a plurality of second candidate path metrics according to each previous path metric and a second branch cost; and a second multiplexer, electrically connected to the comparator and the second combinational circuit, for determining the second path metric according to the control signal and the second candidate path metrics.