SMD 989
– User Manual
Page 48 (105)
Configure Modulator
– DVB-S2X
Configure DVB-S2X modulation.
The SMD 912(A) and SMD 910 modulators are capable of
outputting an extended modulation scheme for DVB-S2 known as DVB-S2X. This output is active
and follows licensing as described earlier in this manual.
To
configure the modulator click on the “
Configure Modulator
Options
” button located at the top of the middle section. The
Configure Modulator menu provides selection of the Modulation Mode. Click the dropdown arrow
and select
DVB-S2X(Single)
.
Figure 41: Configure DVB-SX2 Modulation/FEC
The
Modulation
tab provides setup settings of the modulation parameters. First, choose the
Modulation/FEC code to use and then select how you wish to set the output symbol rate. You
may enter the desired output symbol rate or input bit rate or have the internal calculator
recommend a setting. The following section describes entry of these parameters.
The
Enter Rate By
field provides the user a choice of how to setup the output Symbol Rate or
Max Bitrate entry fields. The values in these fields are mathematically related depending on the
modulation mode, modulation type, and FEC settings. The SDM 989 contains an internal symbol
rate or max. input bitrate calculator to assist.
Enter Rate By
-
Output Symbol Rate
-
Input Bitrate
Description:
Output Symbol Rate mode allows the entry of the desired output symbol rate. The
SMD 989 calculates the maximum input bit rate and lists it in the Max. Bitrate field.
Description: Input Bit Rate mode allows the entry of a known input bit rate. The SMD 989 then
calculates the needed symbol rate and lists it in the Symbol Rate field.
With output Symbol Rate you enter the desired output symbol rate. It must be mathematically
proper based upon the input bit rate measured by the system. When a higher than needed
symbol rate is entered, the modulator inserts null packets to achieve the rate. When entering a
lower than needed symbol rate the SMD 989 removes nulls, if they exist, from the stream.
