Patent ID: 9116826
Filing Date: 2015-08-25
Classification: G06F,H03M

Abstract:
1. A communications apparatus comprising: a constrained interleaver configured to rearrange an ordering of a sequence of N=qm input bits in accordance with a permutation function in order to produce a permuted sequence of output bits, wherein N, q, and m are positive integers and the rearrangement of the ordering in accordance with the permutation function is equivalent to performing the following operations: loading a q×m array of bits, wherein the q×m array has q m-bit rows and m q-bit columns, and the bits are serially loaded into the q×m array along rows, applying an i th pseudo-random row permutation function to each row i, for i=1, 2, . . . q, wherein the i th pseudo-random row permutation function pseudo-randomly rearranges an ordering of the bits in the i th row, applying a j th pseudo-random column permutation function to each q-bit column j, for j=1, 2, . . . m, wherein the j th pseudo-random column permutation function pseudo-randomly rearranges an ordering of the bits in the j th q-bit column, and reading bits out of the q×m array along the q-bit columns to form the permuted sequence of output bits; an outer encoder configured to transform a sequence of mk input message bits to the sequence of N=qm input bits, wherein the sequence of N=qm input bits is encoded in accordance with an outer code, the constrained interleaver is configured to be loaded with an integer number p of q-bit outer codewords per row, where p=m/q, and the outer code is a member of the group consisting of a block code, a LDPC (Low Density Parity Check) code, a convolutional code transformed to a block code, and a non-recursive convolutional code; and an inner encoder configured to transform the permuted sequence of output bits to a sequence of inner-encoded bits, wherein the sequence of inner-encoded bits is encoded in accordance with an inner code; whereby the sequence of inner-encoded bits constitutes a serially-concatenated sequence of bits that incorporates coding from both the inner code and the outer code in accordance with a serially-concatenated code that has a minimum Hamming distance of d wherein the outer code has a minimum Hamming distance of d