TURBO PERMUTATOR AND TURBO DECODER HAVING ITS

摘要

A turbo permutator and a turbo decoder including the same are provided to perform a permutation operation according to forward/reverse direction state metric calculation by pre-calculating a permutation address value of a following step according to a calculation order of the forward/reverse direction state metric. A forward direction address median generator(31) calculates a first median. The first median is used in order to calculate a reverse direction state metric of a first sliding window. A forward/reverse address generator(32) receives the first median, and generates a reverse direction address corresponding to a storage position of a previous log-likelihood ratio. The forward/reverse address generator generates a forward direction address for storing a present log-likelihood ratio. A permutator RAM(33) stores the previous log-likelihood ratio in response to the reverse direction address. The permutator RAM stores a present log ratio in response to the forward direction address.