PARALLEL BIT INTERLEAVER

摘要

A bit interleaving method applying a bit permutation process to a QC LDPC codeword made up of N cyclic blocks of Q bits each, dividing the processed codeword into constellation words of M bits each, and applying an intra-cyclic-block permutation process to the cyclic blocks, where the codeword is divided into F×N/M folding sections of M/F cyclic blocks each and the constellation words are each associated with one of the folding sections, and the bit permutation process is applied such that the constellation words are each made up of F bits from each of M/F different cyclic blocks in the associated section, after the permutation process.

主权项

1. A bit interleaving method for interleaving bits of a codeword generated based on a quasi-cyclic low-density parity check coding scheme, including a repeat-accumulate quasi-cyclic low-density parity check coding scheme, the bit interleaving method comprising:
a bit permutation step of applying a bit permutation process to a codeword made up of N cyclic blocks each consisting of Q bits, to reorder the bits of the codeword in accordance with a bit permutation rule defining a reordering of the bits; and a dividing step of dividing the codeword after the bit permutation process into a plurality of constellation words, each of the constellation words being made up of M bits, wherein N is not a multiple of M, the bit permutation rule includes a first rule and a second rule, the first rule being applied to N′=N−X cyclic blocks, the second rule being applied to X cyclic blocks, the first rule and the second rule differing from each other, where X is a remainder of N divided by M, and the reordering of the first rule is equivalent to a column-row permutation process including a writing process and a reading process, the bits of the N′ cyclic blocks being written into a matrix row-by-row during the writing process, the written bits being read out from the matrix column-by-column during the reading process, the matrix having M rows, the Q bits included in one cyclic block being written into a same row sequentially.