Mocomtech SLM-5650 - Manual (Page 78)

SLM-5650 Satellite Modem Revision 2
Front Panel Operation MN/SLM5650.IOM
4–8
4.3.1.1 Select: CONFIG: Transmit
Mod Permits the user to select: FEC, Type, Rate, RS, Diff, and Scrambler.
DataRate Permits the user to enter a selected data rate and view the symbol rate.
(See Chapter 3.)
Overhead Permits the user to select the overhead type, view the overhead rate, select the
Reed Solomon Code Word, and depth.
Frequency Permits the user to select the desired frequency and spectral inversion.
Power Permits the user to select desired output power level and state of the output.
Clocking Permits the user to select the transmit clock source and SCT reference.
Misc Permits the user to select CLK/DataPhase and BPSK Bit Ordering.
Select: CONFIG: Transmit: Mod
Select the Mod type using the ef arrow keys to scroll through all the choices, as
follows. The user should then press [E].
FEC (Viterbi or None are standard), (TURBO optional) Viterbi is a K=7
convolutional encoder. None means Uncoded. Turbo means Turbo Product
Code, which is a block code. Trellis operation is supported in IESS-310 mode
and MIL-STD-188-165A mode, which for the encoder is just a specific mapping
of the constellation. Trellis is not a displayed choice.
Type
(Modulation) (BPSK, QPSK, OQPSK standard), (8PSK, or 16QAM optional) BPSK stands
for Bi Phase Shift Keying. QPSK stands for Quadrature Phase Shift Keying.
OQPSK stands for Offset Quadrature Phase Shift Keying. 8PSK stands for
8 Phase Shift Keying. 16QAM stands for 16 Quadrature Amplitude Modulation.
Rate Viterbi: 1/2, 2/3, 3/4, 5/6, or 7/8
Uncoded: 1/1
Turbo: 5/16, 21/44, 3/4, 7/8, or 17/18
RS On or Off (Reed Solomon Encoder)
Diff On or Off (Differential Encoder)
Scram:
V.35, M-V.35, IBS, TURBO, OM73, Synch, or Off
(Scrambling is for energy dispersal)
V.35 ITU standard
M-V.35 EF Data Closed Network with Reed Solomon compatible (modified V.35)
IBS Used for IESS-309 and AUPC operation
Turbo Synchronous scrambler synchronized to the Turbo block
OM73 Linkabit OM-73 modem compatibility mode
Synch Synchronous scrambler synchronized to the Reed-Solomon.
Tx: Mod DataRate Overhead Frequency
Power Clocking Misc (
efE)
Mod: FEC:VIT Type:QPSK Rate:1/2
RS:Off Diff:On Scram:OM-73 (
efE)