Mocomtech SLM-5650 - Manual (Page 82)

SLM-5650 Satellite Modem Revision 2
Front Panel Operation MN/SLM5650.IOM
4–12
Note: Framing is applicable only when using externally framed data, with the following
formats:
T1 or E1 G.704
T2 G.743, G.704, G.707
E2 G.742, G.704, G.745
Select: CONFIG: Receive: Demod
Select the Demod, Type, RS, Diff, and Descram. Use the ef arrow keys to scroll
through all the choices. The user should then press [E].
FEC (Viterbi or None are standard), (TURBO optional) Viterbi is a K=7
convolutional decoder. None means Uncoded. Turbo means Turbo Product
Code, which is a block code. Trellis operation is supported in IESS-310 or MIL-
STD-188-165A mode which a different front end is applied the Viterbi decoder.
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. 8-PSK stands for
8 Phase Shift Keying. 16-QAM 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 Decoder)
Diff On or Off (Differential Decoder)
Descram: V.35, M-V.35, IBS, TURBO, OM73, Synch, or Off (Descrambling)
V.35 ITU standard
M-V.35 EF Data Closed Network with Reed Solomon compatible (modified V.35)
IBS Used for IESS-309 operation
Turbo Synchronous descrambler synchronized to the Turbo block
OM73 OM-73 Linkabit modem compatibility mode
Synch Synchronous descrambler synchronized to the Reed-Solomon frame.
IMPORTANT
When changing Modulation type the data rate must be set to a rate
supported by the modulation type or the change to the modulation type
will not be allowed. Some choices will only be visible if the modem is
set to a compatible mode or if an option is installed or enabled.
Demod: FEC:VIT Type:BPSK Rate:3/4
RS:N/A Diff:On Descram:OM-73 (
efE)