Config: Tx  Mod (Modulation) - Comtech EF Data CDM-625A Installation And Operation Manual

CDM-625A Advanced Satellite Modem
Front Panel Operation
Otherwise, when Diff Encoder is selectable on the bottom line:
CONFIG: Tx  FEC  Diff Encoder On
Enc=None(Vit,Seq,TCM,TPC,LDPC,VFEC,ULL)
Diff Encoder=On (Off,On)
Use the arrow keys to select the Diff Encoder as On or Off. Press ENTER:
▲▼
When you select Differential Encoding=OFF, there is no way for the modem to
resolve the phase ambiguities associated with PSK modulations. For BPSK there is a
50% chance that the polarity of the data will be correct. In QPSK there is a 25%
chance that the data will be correct.
6.2.1.3.5 CONFIG: Tx  Mod (Modulation)
Mod=QPSK
FEC Rate=1/2
Use the ◄ ► arrow keys to select the Mod (modulation type) (top line) or the FEC Rate (bottom
line). Press ENTER. Then, use the
Encoder type dictates the Modulation Type and FEC rate selections:
Encoder Type
No Encoder
Non-Turbo Encoder
TPC
(with TPC/LDPC hardware option
installed)
LDPC
(with TPC/LDPC hardware option
installed)
VFEC
ULL
(VersaFEC Ultra-Low Latency)
(B,Q,OQ,8PSK,16Q,8QAM)
(1/2,3/4,7/8)
arrow keys to change that parameter selection. The
▲▼
Modulation Type
BPSK
QPSK, OQPSK
BPSK
TCM 8-PSK (FAST option)
QPSK, OQPSK
16-QAM (Vit+RS only)
BPSK
QPSK, OQPSK
8-PSK (FAST option)
16-QAM (FAST option)
BPSK
QPSK, OQPSK
8-PSK, 8-QAM (FAST)
16-QAM (FAST option)
BPSK
QPSK
8-QAM (FAST option)
16-QAM (FAST option)
BPSK
QPSK
6–18
MN-CDM625A
Revision 4
()
()
FEC Rate Choice
Fixed at 1/1
Fixed at 1/1
Fixed at 1/2
Fixed at 2/3
1/2, 3/4, 7/8
3/4, 7/8
5/16, 21/44
1/2 (aka 21/44), 3/4, 7/8, 0.95
3/4, 7/8, 0.95
3/4, 7/8
Fixed at 1/2
1/2, 2/3, 3/4
2/3, 3/4
Fixed at 3/4
Fixed at 0.488
0.533, 0.631, 0.706, 0.803
0.576, 0.642, 0.711, 0.780
0.644, 0.731, 0.780, 0.829, 0.853
Fixed at 0.493
0.493, 0.654, 0.734