L64704 LSI Logic Corporation, L64704 Datasheet - Page 141

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

Table 6.1
Stage 2
Synchronization Values
Bit Error Rate
5.0e - 04
1.0e - 03
2.0e - 03
5.0e - 03
1.0e - 02
2.0e - 02
5.0e - 02
Figure 6.9
L64704 Transport
Packet
Inverting
# frames
Table 6.1
mean time to loss of lock (T
chronization stage 2 as a function of the incoming bit error rate (code
word length = 204 bytes, sync word length = 8 bits, K = 0, L = 2,
60 Mbits/s):
For an expected BER of 1.0e - 03, the decoder requires about four frame
times to establish synchronization, and loss of sync occurs after
9.0e + 15 frames. With one modification, the DVB Standard of the Euro-
pean Broadcast Union has adopted this basic format as a standard for
multiprogram TV via satellite. One out of every eight synchronization
words in the data stream is mod 2 complemented.
data format of the L64704 transport packet.
Given a bit stream that consists of a sequence of these packets, the
second synchronization stage searches for the predefined sync byte and,
upon having met the synchronization acquisition criteria, issues the
control strobes for the modules that follow.
Reed-Solomon Deinterleaver Synchronization
Sync
Byte
3.88
3.91
3.98
4.16
4.48
5.15
7.23
204 Bytes
shows the computed values for mean acquisition time (T
T
ac
1.05e - 04
1.06e - 04
1.07e - 04
1.12e - 04
1.21e - 04
1.39e - 04
1.98e - 04
sec
8 X 204 Bytes
ll
), and probability of false lock (P
9.00e + 15
9.00e + 15
9.00e + 15
4.50e + 15
6.37e + 12
1.39e + 10
5.21e + 06
# frames
Sync
Byte
T
ll
2.44e + 11
2.44e + 11
2.44e + 11
1.22e + 11
1.72e + 08
3.78e + 05
1.41e + 02
sec
Figure 6.9
Inverting
Sync
Byte
5.98e - 08
5.98e - 08
5.98e - 08
5.98e - 08
5.98e - 08
5.98e - 08
5.98e - 08
shows the
fl
) for syn-
sec
P
fl
ac
),
6-9