An OFDM, Orthogonal Frequency Division Multiplexing, signal generation method comprising: an encoding step of encoding information bits into a codeword according to a low density parity check code with code rate 7/15 and a codeword length of 16200, the low density parity check code shown in Table 1-1: a bit-interleaving step of conducting parity interleaving and column-row interleaving on bits of the codeword obtained in the encoding step, the column-row interleaving being conducted with twist; a bit-to-cell demultiplexing step of demultiplexing a sequence of bits interleaved in the bit-interleaving step into 8 sequences of bits v i,j, wherein i denotes one of the 8 sequences and bit v i,j corresponds to bit v i+8×j of said sequence of interleaved bits, and performing a permutation on the 8 sequences of bits according to a predetermined permutation rule so as to permute each set of 8 bits (v 0,q, v 1,q, v 2,q, v 3,q, v 4,q, v 5,q, v 6,q, v 7,q) to a set of 8 bits (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) to obtain 8 sequences of permuted bits, where q is an index; a mapping step of mapping each of 8-bit cell words (y 0,q, y 1,q, y 2,q, y 3,q, y 4,q, y 5,q, y 6,q, y 7,q) each composed of a set of 8 bits (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) of the 8 sequences of permuted bits obtained in the bit-to-cell demultiplexing step, into a complex cell (Re(Z q), Im(Z q)) according to the 256QAM, Quadrature Amplitude Modulation, constellation shown in Tables 1-2 and 1-3; [Table 1-2] y 0,q 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 y 2,q 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 y 4,q 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 y 6,q 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 Re( z q) -15 -13 -11 -9 -7 -5 -3 -1 1 3 5 7 9 11 13 15 [Table 1-3] y 1,q 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 y 3,q 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 y 5,q 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 y 7,q 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 Im( z q) -15 -13 -11 -9 -7 -5 -3 -1 1 3 5 7 9 11 13 15 a frame building step of assembling a transmission frame from the complex cell generated in the mapping step; and an OFDM signal generation step of generating OFDM signals by adding pilots, applying an inverse Fast Fourier Transform, and performing guard interval insertion with respect to the transmission frame assembled in the frame building step, wherein (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) = (y 0,q, y 1,q, y 2,q, y 3,q, y 4,q, y 5,q, y 6,q, y 7,q), and the predetermined permutation rule is: V 0,q = b 2,q, v 1,q = b 6,q, v 2,q = b 0,q, v 3,q = b 1,q, v 4,q = b 4,q, v 5,q = b 5,q, v 6,q = b 3,q, v 7,q = b 7,q. an encoding step of encoding information bits into a codeword according to a low density parity check code with code rate 7/15 and a codeword length of 16200, the low density parity check code shown in Table 1-1: a bit-interleaving step of conducting parity interleaving and column-row interleaving on bits of the codeword obtained in the encoding step, the column-row interleaving being conducted with twist; a bit-to-cell demultiplexing step of demultiplexing a sequence of bits interleaved in the bit-interleaving step into 8 sequences of bits v i,j, wherein i denotes one of the 8 sequences and bit v i,j corresponds to bit v i+8×j of said sequence of interleaved bits, and performing a permutation on the 8 sequences of bits according to a predetermined permutation rule so as to permute each set of 8 bits (v 0,q, v 1,q, v 2,q, v 3,q, v 4,q, v 5,q, v 6,q, v 7,q) to a set of 8 bits (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) to obtain 8 sequences of permuted bits, where q is an index; a mapping step of mapping each of 8-bit cell words (y 0,q, y 1,q, y 2,q, y 3,q, y 4,q, y 5,q, y 6,q, y 7,q) each composed of a set of 8 bits (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) of the 8 sequences of permuted bits obtained in the bit-to-cell demultiplexing step, into a complex cell (Re(Z q), Im(Z q)) according to the 256QAM, Quadrature Amplitude Modulation, constellation shown in Tables 1-2 and 1-3; [Table 1-2] y 0,q 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 y 2,q 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 y 4,q 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 y 6,q 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 Re( z q) -15 -13 -11 -9 -7 -5 -3 -1 1 3 5 7 9 11 13 15 [Table 1-3] y 1,q 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 y 3,q 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 y 5,q 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 y 7,q 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 Im( z q) -15 -13 -11 -9 -7 -5 -3 -1 1 3 5 7 9 11 13 15 a frame building step of assembling a transmission frame from the complex cell generated in the mapping step; and an OFDM signal generation step of generating OFDM signals by adding pilots, applying an inverse Fast Fourier Transform, and performing guard interval insertion with respect to the transmission frame assembled in the frame building step, wherein (b 0,q, b 1,q, b 2,q, b 3,q, b 4,q, b 5,q, b 6,q, b 7,q) = (y 0,q, y 1,q, y 2,q, y 3,q, y 4,q, y 5,q, y 6,q, y 7,q), and the predetermined permutation rule is: V 0,q = b 2,q, v 1,q = b 6,q, v 2,q = b 0,q, v 3,q = b 1,q, v 4,q = b 4,q, v 5,q = b 5,q, v 6,q = b 3,q, v 7,q = b 7,q.