Newtec EL470, Справочное руководство

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Modem
Reference Manual for EL470 IP Satellite Modem
Command
InpRateEstim Estimated input bitrate Estim input bitrate
Location /Modem/Monitor/Modulation
Description
Readout of the estimated input bitrate. The concentrator provides an
estimate of the input bitrate on every input channel in order to help the
operator in determining a suitable output bitrate.
Remark: Only applicable when an auxiliary ASI board is installed.
RMCP
Command DIR Access Normal user : R
Expert user : R
SNMP Table ntcDevsMod01ModulatorEntry
Command ntcDevsMod01InpRateEstim
OID 1.3.6.1.4.1.5835.3.1.3.1.51.1.1
Values GUI Unit
Mbps
Cmd Unit Factory Default (CU)
bps 0
Expert Range (CU)
0 .. 4294967295
Command
MoBufCont Buffer contents Buffer contents
Location /Modem/Monitor/Modulation
Description
Readout of the content of the FIFO buffer between the interface and the
modulator part. The buffer content is expressed in % of the physical buffer
size.
•
In DVB-S operation :The buffer is re-centred in case of underflow or
overflow. When the device operates with external transmit clock,
then a PLL loop maintains the buffer contents at the nominal set
point. For the lower bit-rates, the nominal set point is reduced in
order to minimize overall delay.The nominal buffer set-points are:a)
Set-point = 50% when 1 Mbit/s <= interface rate.b) Set-point = 25%
when 200 kbit/s <= interface rate < 1 Mbit/s.c) Set-point = 12.5%
when 50 kbit/s <= interface rate < 200 kbit/s. The actual buffer
contents varies as function of the timing format of the baseband
input transport stream (for a detailed explanation see timing
format).In byte mode, the actual average buffer contents will be
close to the nominal set-point. In packet mode, the actual average
buffer contents will be about half a DVB packet (188/2 = 94 bytes)
above the nominal set-point due to the bursty nature of this format.
•
In DVB-S2 operation :In DVB-S2 mode, data buffering occurs both in
the input FIFO buffer and in the baseband processing circuits. The
large input FIFO is mainly present for the asynchronous (internal
transmit clock or stuffing mode) operation, but can cause excessive
processing delays in the synchronous slaved mode (external
transmit clock) with short-frames. Therefore the nominal buffer set-
point is no longer fixed but user-programmable via the
MoBufSetp
and MoBufFramSetp commands.Remark: In addition, a minimum-
delay mode is included (see MoDlyMode ) which initializes the
baseband circuits for minimum delay operation. In this case the input
buffer will remain empty.
RMCP
Command Tip Access Normal user : R
Expert user : R
SNMP Table ntcDevsMod01ModulatorEntry
Command ntcDevsMod01MoBufCont
OID 1.3.6.1.4.1.5835.3.1.3.1.5.1.1
version 3.1
147
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