Newtec EL470, Справочное руководство

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Modem
Reference Manual for EL470 IP Satellite Modem
Command
MoAESOddKeyISI Odd Key Odd Key
Location /Modem/Control/Modulation/AES/Keys 1-4
Description
This is the AES ODD key (non-encrypted) entered by the user.
This can be either 64bits or 128bits long, depending on the key length
setting.The value is entered as a hexadecimal value:
•
64 bits - 8 bytes (16 text bytes)
•
128 bits - 16 bytes (32 text bytes)
RMCP
Command mOk
array : [1 .. 4] Access Normal user : RW
Expert user : RW
SNMP Table ntcDevsMod01ModulatorExtEntry
Command ntcDevsMod01MoAESOddKeyISI
OID 1.3.6.1.4.1.5835.3.1.3000.1.17.1.1.[1 .. 4]
Values Factory Default
FFFFFFFFFFFFFF
FFFFFFFFFFFFFF
FFFF
String Description
length : 0 .. 32
format : Hexadecimal chars
/Modem/Control/Demodulation
Command
DmACMMode DVB-S2 Coding and
Modulation mode DVB-S2 mode
Location /Modem/Control/Demodulation
Description
Configuration of the DVB-S2 coding and modulation mode.
The DVB-S2 standard defines adaptive coding and modulation (ACM) and
constant coding and modulation (CCM). The modulation parameters in
ACM and CCM mode are:
•
Modcod: Definition which coding and modulation is used.
•
Pilot insertion: Presence or not of pilots in the physical layer frame.
•
Frame type: Short frames (2025 bytes) or normal frames (8100
bytes).Explanation of the different modes:
•
Definition CCM : Constant coding and modulation parameters are
fixed for all input streams (components). The user can change the
settings of these parameters.
•
Definition auto-CCM : CCM mode with auto detection of the
parameters. The adaptable parameters are part of the received
physical layer frame that way the user can not change any of these
parameters. Best practise is to set the demodulator in auto-CCM
mode. In this mode, the demodulator will extract the demodulation
parameters (modcod, pilots and frame type) from the incoming
stream. The demodulator board will look at the physical layer header
of the first received DVB-S2 baseband frame to extract the
demodulation parameters. It will use those parameters for all other
received DVB-S2 baseband frames. In CCM mode, the user has to
tell the demodulator manually what demodulation parameters to use.
•
Definition ACM : Adaptive coding and modulation parameters can
vary on a frame by frame basis (even for a single component). The
adaptable parameters are part of the received physical layer frame.
This way the user can not change any of these parameters. ACM is
needed to handle the discontinuous data stream. The modulator
board receives DVB-S2 baseband frames from the gigabit Ethernet
version 3.1
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