Receiving apparatus and de-interleaving method thereof
A transmitting apparatus and a receiving apparatus are provided. The transmitting apparatus includes: an encoder configured to generate a low density parity check (LDPC) codeword by LDPC encoding based on a parity check matrix; an interleaver configured to interleave the LDPC codeword; and a modulator configured to map the interleaved LDPC codeword onto a modulation symbol, wherein the modulator is further configured to map a bit included in a predetermined bit group from among a plurality of bit groups constituting the LDPC codeword onto a predetermined bit of the modulation symbol.
1. A television (TV) broadcast receiving apparatus comprising:
a receiver configured to receive a broadcast signal from a TV broadcast transmitting apparatus;
a demodulator configured to demodulate the signal to generate values according to a quadrature phase shift keying (QPSK) modulation;
a deinterleaver configured to split the values into a plurality of groups and deinterleave the plurality of groups to provide deinterleaved values; and
a decoder configured to decode the deinterleaved values based on a low density parity check (LDPC) code having a code rate being 5/15 and a code length being 16200 bits,
wherein the plurality of groups are deinterleaved based on a following equation:
Y π( j )= Xj for (0 ≤j<N group ),
where Xj is a jth group among the plurality of groups, Yj is a jth group among the deinterleaved plurality of groups, Ngroup is a total number of the plurality of groups, and π(j) denotes a deinterleaving order for the deinterleaving, and
wherein the π(j) is defined as follows:
Order of deinterleaving
π(j) (0 ≤ j < 45)
Code
j
0
1
2
3
4
5
6
7
8
9
10
11
Rate
23
24
25
26
27
28
29
30
31
32
33
34
5/15
π(j)
35
7
29
11
14
32
38
28
20
17
25
39
5
13
34
37
23
15
36
18
42
16
33
31
Order of deinterleaving
π(j) (0 ≤ j < 45)
Code
j
12
13
14
15
16
17
18
19
20
21
22
Rate
35
36
37
38
39
40
41
42
43
44
5/15
π(j)
19
4
1
12
10
30
0
44
43
2
21
27
22
3
6
40
24
41
9
26
8.
2. The receiving apparatus of claim 1 , wherein each of the plurality of groups comprises 360 values.
3. The receiving apparatus of claim 1 , wherein π(j) is determined based on at least one of the code length, a modulation method and the code rate.