L64704 LSI Logic Corporation, L64704 Datasheet - Page 152

• Manufacturer Part Number: L64704
• Description: Satellite Decoder Technical Manual 5/97
• Manufacturer: LSI Logic Corporation

Figure 7.5
Block Diagram of
Viterbi Bit Error
Detection Circuit
Configuration
7-8
Parameter
Symbol 1
Symbol 0
Depuncture
Max Data
(VMDC2)
Bit Count
Module
To assist the proper selection of the ratio of the threshold values VMDC1
and VBERC,
centages of symbol errors vs. Eb/No for all the code rates that the
L64704 supports. The upper curve in each graph represents the out-of-
synchronization condition, and the lower curve represents the in-
synchronization condition.
The FEC Decoder Pipeline
Depunctured
24
Data
Figure 7.6
Rate = 1/2
Data Bit
Decoder
Decoder
Viterbi
Count
Delay
Core
Data
Line
through
Figure 7.10
Convolutional
Channel Data
Comparator
Error Count
Encoder
Bit Error Events
Decoded Data
show the plots of the per-
L64704 Sets
VBER Flag
Bit Error
16
Count
To
Microcontroller
Interface