Transmitting apparatus and interleaving method thereof

A transmitting method comprising:

• encoding input bits to generate a codeword based on a low density parity check (LDPC) code, a code rate of the LDPC code being 5/15 and a code length of the LDPC code being 16200 bits;
• splitting the codeword into a plurality of bit groups;
• interleaving the plurality of bit groups;
• interleaving bits of the interleaved plurality of bit groups;
• mapping the interleaved bits to constellation points for 64-quadrature amplitude modulation (QAM);
• and
• transmitting a signal which is generated based on the constellation points,
• wherein the plurality of bit groups are interleaved as follows:
• Y
• j
• =
• X
• π
• ⁡
• (
• j
• )
• ⁢
• ⁢
• for
• ⁢
• ⁢
• (
• 0
• ≤
• j
• <
• N
• g
• ⁢
• roup
• )
• ,
• where Xj is a j-th bit group among the plurality of bit groups, Yj is a j-th bit group among the interleaved plurality of bit groups, Ngroup is a number of the plurality of bit groups and π(j) denotes an interleaving order for the interleaving, and
• wherein the π(j) is represented as follows:
• The Interleaving Order
• π(j) (0 ≤j <45)
• j
• 0
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• 10
• 11
• 12
• 13
• 14
• 15
• 16
• 17
• 18
• 19
• 20
• 21
• 22
• 23
• 24
• 25
• 26
• 27
• 28
• 29
• 30
• 31
• 32
• 33
• 34
• 35
• 36
• 37
• 38
• 39
• 40
• 41
• 42
• 43
• 44
• π(j)
• 25
• 44
• 8
• 39
• 37
• 2
• 11
• 7
• 0
• 12
• 4
• 31
• 33
• 38
• 43
• 21
• 26
• 13
• 28
• 29
• 1
• 27
• 18
• 17
• 34
• 3
• 42
• 10
• 19
• 20
• 32
• 36
• 40
• 9
• 41
• 5
• 35
• 30
• 22
• 15
• 16
• 6
• 24
• 23
• 14