Modem
Reference Manual for EL470 IP Satellite Modem
Command
DmSpecInv
Rx spectrum inversion Rx spectrum inversion
Location
/Modem/Control/Demodulation
Description
Configuration command for the received spectrum. The selection of the
auto mode allows the device to solve the spectrum ambiguity when the
status of the received spectrum is unknown. When the status of the
received spectrum is known (spectrum inversion on or off), do not use the
auto mode since it will increase the acquisition time. In a converter, the
auto mode is not available and spectral inversion has to be set manually.
RMCP
Command
RMi
Access
Normal user : no access
Expert user : RW
SNMP
Table
ntcDevsMod01DemodulatorEntry
Command
ntcDevsMod01DmSpecInv
OID
1.3.6.1.4.1.5835.3.1.13.1.23.1.1
Values
Factory Default
invertedSpectrum
Enumeration
Value
Auto
Direct
Inverted
0
1
2
Command
DmPLSSignature
Physical Layer
Scrambler signature
PLS signature
Location
/Modem/Control/Demodulation
Description
Configuration of the physical layer scrambler (PLSCRAMBLER) signature.
The physical layer scrambler scrambles all of the physical layer frames
except for their header parts. The sequence is reset at the start of the
frame body.
The physical layer scrambler signature assumes values in the range
between 0 and 262141.It indicates the spreading sequence number. The
use of different physical layer scrambling sequences allows a reduction of
interference correlation between different services. For the same purpose,
it is possible to reuse a shifted version of the same sequence in different
satellite beams. Furthermore the spreading sequence number can be
unequivocally associated to each satellite operator or satellite or
transponder, thus permitting identification of an interfering signal via the
physical layer scrambling signature detection. There is no explicit signaling
method to convey the spreading sequence number to the receiver.
In case of broadcasting services, the default physical layer scrambler
signature (value = 0) shall be used, to avoid manual receiver setting or
synchronisation delays.
RMCP
Command
Pss
Access
Normal user : no
access
Expert user : RW
SNMP
Table
ntcDevsMod01DemodulatorEntry
Command
ntcDevsMod01DmPLSSignature
OID
1.3.6.1.4.1.5835.3.1.13.1.73.1.1
Values
GUI Unit
NA
Cmd Unit
Factory Default (CU)
NA
0
Expert Range (CU)
0 .. 262141
version 3.1
105
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