VP310

PRELIMINARY DATA

9

0

1

2

3

4

5

6

7

8

9

10

11

0

1

2

3

4

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9

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Sync word route

17x1

17x2 bytes

17x3 bytes

17x4 bytes

17x5 bytes

17x6 bytes

17x7 bytes

17x8 bytes

17x9 bytes

17x10 bytes

17x11 bytes

one

byte per

position

1.4.3.2 DSS

Before transmission, the data bytes are interleaved with each other in a cyclic pattern of thirteen.

This ensures the bytes are spaced out to avoid the possibility of a noise spike corrupting a group

of consecutive message bytes. The diagram below shows conceptually how the convolutional de-

interleaving system works. On the VP310, this function is realised in the same Random Access

Memory (RAM) as used for DVB, but utilising different addressing algorithm.

12D

12D

12D

0

1

Output

145

Input

2

Figure 6. DSS Conceptual diagram of the convolutional de-interleaver block.