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ETSI ES 201 980 V4.1.2 (2017-04)

Four overall code rates are defined independently for the VSPP as follows.

Table 34: Code rate combinations for the VSPP of MSC with HMsym 64-QAM (robustness modes A, B, C and D)

Protection level

R0

 

0

1/2

 

1

4/7

 

2

3/5

 

3

2/3

NOTE:

These code rates are also used

 

for the real part of HMmix.

Annex J provides the number of input bits per multiplex frame for EEP.

7.5.1.3HMmix

Two protection levels are possible resulting in the use of two overall code rates. The number of input bits LMUX per multiplex frame is calculated with the formulas of clause 7.2.

The MSC shall be encoded according to clause 7.3. The protection level is signalled in the multiplex description data entity of the SDC (see clause 6.4.3.1).

Four overall code rates are defined for the SPP as shown in table 35 and the four possible code rates for the VSPP are defined independently as shown in table 34.

Table 35: Code rate combinations for the SPP of MSC with HMmix 64-QAM (robustness modes A, B, C and D)

Protection level

Rall

R Im

R Re

R Im

R Re

R Im

RYlcm

 

 

0

1

1

2

2

 

0

0,48

1/4

3/10

1/2

3/5

3/4

20

1

0,58

1/3

4/11

2/3

8/11

4/5

165

2

0,71

1/2

4/7

3/4

7/8

7/8

56

3

0,78

2/3

2/3

4/5

8/9

8/9

45

Annex J provides the number of input bits per multiplex frame for EEP.

7.5.2Coding the SDC

The SDC may use either 16-QAM or 4-QAM mapping with code rate 0,5 for robustness modes A, B, C and D and 4-QAM mapping with code rate 0,5 or 0,25 for robustness mode E. In each robustness mode, a choice is available between greater capacity and a more robust error performance. In each case, a fixed code rate is applied.

The constellation and code rate should be chosen with respect to the MSC parameters to provide more robustness for the SDC than for the MSC. When using hierarchical modulation, the SDC shall be coded using 4-QAM.

The number of input bits LSDC per SDC block is calculated as given in clause 7.2.

For 16-QAM the combination given in table 36 shall be used.

Table 36: Code rate combinations for the SDC with 16-QAM (robustness modes A, B, C and D)

Protection level

Rall

R0

R1

0

0,5

1/3

2/3

For 4-QAM one of the code rates given in table 37 or table 38 shall be used.

ETSI

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