A code bit of an LDPC code in which a code length is 16200 bits and an encoding rate is 7/15 is interchanged with a symbol bit of a symbol corresponding to any of 8 signal points defined by 8PSK. In the interchanging, when 3 bits of code bits stored in three units of storages having a storage capacity of 16200/3 bits and read bit by bit from the units of storages are allocated to one symbol, a (#i +1)-th bit from a most significant bit of the 3 bits of code bits is set to a bit b#i, a (#i +1)-th bit from a most significant bit of 3 bits of symbol bits of the one symbol is set to a bit y#i, and a bit b0, a bit b1, and a bit b2 are interchanged with a bit y1, a bit y0, and a bit y2.