Newtec EL470 - Page 83

Modem Reference Manual for EL470 IP Satellite Modem
Command
MoGainCtrlMode
Gain control mode Gain control mode
Location /Modem/Control/Modulation/Main
Description
Configuration of the output level gain control mode. The modulator output
level accuracy can be controlled statically in the fixed manual gain control
mode or by using an automatic gain feedback control loop.
In some communication systems with multiple overall automatic gain
control, it might be necessary to set the output level of the modulator to
manual gain control. The automatic gain control mode is used to keep
level changes in output level caused by gain drift of the amplifier stages of
the modulator (due to temperature changes or ageing) small.
RMCP
Command
Gcm Access Normal user : no access
Expert user : RW
SNMP Table ntcDevsMod01ModulatorEntry
Command ntcDevsMod01MoGainCtrlMode
OID 1.3.6.1.4.1.5835.3.1.3.1.12.1.1
Values Factory Default
agc
Enumeration Value
MGC
AGC
0
1
Command
MoOutLevelPlan
Output Level Plan Output Level Plan
Location /Modem/Control/Modulation/Main
Description
Configuration of the output level plan. The modulator features two output
level plans:
• Constant power: In this plan is the output power kept equal for the
different modcods. This is the default mode of operation.
• Constant rim: In this plan, the outer ring of the symbol constellation
is kept equal for the different modcods. As a consequence different
modcods will be transmitted with different output power.The constant
rim mode is used for VCM/ACM demodulator operation with a
saturated transponder. It avoids excessive input back-off for QPSK,
8PSK and 16APSK modcods during VCM/ACM operation. Due to
the dynamic level changes, this mode is only possible with manual
gain control. Since the highest outer ring level occurs for a modcod
of 32APSK-3/4, this modcod is used as the reference for the output
power level setting. The other modcods will be transmitted with
higher power:
RMCP
Command
olp Access Normal user : no access
Expert user : RW
SNMP Table ntcDevsMod01ModulatorEntry
Command ntcDevsMod01MoOutLevelPlan
OID 1.3.6.1.4.1.5835.3.1.3.1.99.1.1
Values Factory Default
const_Power
Enumeration Value
Const. Pwr
Const. Rim
0
1
version 3.1
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