VITERBI DETECTOR, SIGNAL PROCESSING CIRCUIT, RECORDING AND REPRODUCING DEVICE AND INFORMATION PROCESSING SYSTEM

摘要

PROBLEM TO BE SOLVED: To reduce power consumption. SOLUTION: In the case that likelihood calculation is executed on the basis of the Viterbi algorithm, a decoded value series is estimated and they are stored in path memories (630-633), a convergence discriminator (660) discriminates whether an alive path is converged on the basis of the values stored in each stage of the path memories (630-633). When the discriminator (660) discriminates that the alive path has converged, the discriminator (660) stops the operation of the path memories (630-633) that store information prior to the point of time of convergence except one path memory (630) that is selected optionally (but fixedly). Then the discriminator (660) outputs the output of the path memory (630) whose operation has not been stopped as a decoding result. Since the operation of the path memories whose alive path has converged is stopped, the power consumption can be reduced.