CDM-625 Advanced Satellite Modem
Revision 1
Forward Error Correction Options
MN-0000036 (Ref MN/CDM625.IOM)
1E-9
1E-8
1E-7
1E-6
1E-5
1E-4
1E-3
1E-2
1E-1
1 2 3 4 5 6 7 8 9 10 11 12
Eb/No in dB
Specification
Limit Rate 1/2
and 220,200
Outer Code
Uncoded BPSK/QPSK
1 2 3 4 5 6 7 8 9 10 11 12
BER
Viterbi with
concatenated
RS 220,200
Outer Code
Combined sync
threshold, demod
and Viterbi
Decoder, Rate 1/2
Sync
threshold,
Rate 3/4
Specification
Limit Rate 3/4
and 220,200
Outer Code
Specification
Limit Rate 7/8
and 220,200
Outer Code
Sync
threshold,
Rate 7/8
Typical performance
Figure 7-2. Viterbi with concatenated R-S Outer Code
7–12
