Patent ID: 8171371

Claim:
A method of generating a parity check matrix for low-density parity check codes, the method comprising: quasi-cyclic matrix generating including generating a regular quasi-cyclic matrix with uniform weights of a row and a column, in which cyclic permutation matrices are arranged in a row direction and a column direction and specific regularity is given to the cyclic permutation matrices; mask-matrix generating including generating a mask matrix for making the regular quasi-cyclic matrix into irregular with nonuniform weights of a row and a column, the mask matrix being capable of supporting a plurality of encoding rates; masking including converting a specific cyclic permutation matrix in the regular quasi-cyclic matrix into a zero-matrix using a mask matrix corresponding to a specific encoding rate to generate an irregular masking quasi-cyclic matrix; and check-matrix generating, by a communication apparatus, including generating an irregular parity check matrix with a low-density generation matrix structure in which the masking quasi-cyclic matrix and a matrix in which the cyclic permutation matrices are arranged in a staircase manner are arranged in a predetermined location.