BIT INTERLEAVER FOR A BICM SYSTEM WITH QC LDPC CODES

摘要

Bit interleaving method for interleaving a QC-LDPC codeword made up of N cyclic blocks each consisting of Q cyclic block bits and the constellation word being made up of M bits with N being not a multiple of M. The bit interleaving comprises a cyclic block permutation step, a bit permutation step and a dividing step, where the N-N' cyclic blocks, with N' = N - rem(N, M) and including a cyclic block in a parity section of the codeword, are excluded from the bit permutation process. After the cyclic block permutation process, the N' cyclic blocks are divided so that the Q bits in each of the N' cyclic block are each allocated to a bit of an identical bit index in Q constellation words and said Q constellation words are each made up of one bit from each of M different cyclic blocks, said M different cyclic blocks being common to said Q constellation words.