Patent ID: 8745473

Claim:
An encoder comprising: a coding section that generates coded sequence s that is made up of z×n b bits and satisfies equation 1-1, equation 1-2 and equation 1-3 for information bit sequence u; and a selecting section that selects either of a puncturing pattern for removing a column group that corresponds to consecutive y bits and a puncturing pattern for not removing a column group that corresponds to the consecutive y bits as a puncturing pattern having a unit of divisor y of a number of columns z for each y bits from a first bit to a z×n b -th bit, a puncturing section that determines bits to be removed for each y bits based on the selected puncturing pattern, removes the bits determined to be removed from the z×n b bits configuring the coded sequence s to form a transmission information bit sequence, and outputs the transmission information bit sequence, wherein the selecting section selects a column group from a plurality of column groups having column weight of 3 in a matrix that corresponds to the information bit sequence u, the matrix includes a plurality of column groups having column weight of equal to or greater than 3, and the matrix is included in a parity check matrix H of an low density parity check code, and the selecting section selects two column groups in a matrix that corresponds to a parity bit sequence and is included in the parity check matrix H of the low density parity check code: [1] GH T =0 (Equation 1-1) s T =Gu T (Equation 1-2) Hs= 0 (Equation 1-3) where H is a parity check matrix of an low density parity check code of z×m b rows and z×n b columns configured by arranging submatrixes of z rows and z columns in m b rows and n b columns, G is a generator matrix holding a relationship of equation 1-1 with parity check matrix H of the low density parity check code and the coded sequence s is a coded sequence made up of z×n b bits.