Chapter 11 DSNG Configuration
© 2013 Harmonic Inc. Harmonic All rights reserved.
322
Ellipse 3000 Release 3.0, Rev. B
Common Modulation Parameters
11.4.8
Roll-Off Factor
The Roll-Off Factor parameter sets the modulation roll-off value. The roll-off factor is responsible
for the quality of separation between partly overlapping satellite transmissions frequency
envelopes. Setting a large Roll-off value allows a larger portion of the relevant transmission to be
received, but also receives more irrelevant signals from the adjacent transmission. Setting a
smaller Roll-off value reduces the mount of irrelevant data from the adjacent transmission, but
also loses some information found in the edges of the relevant transmission envelope.
The available options are: 0.20, 0.25 or 0.35. The Roll-Off Factor default value is
0.35
.
Front Panel
To set the Roll-Off Factor parameter on the front panel:
❖
Navigate
Root > IF
or
L-Band Modulation > Roll-Off Factor
.
Web Manager
To set the Roll-Off Factor parameter in the Web Manager:
❖
Select
DSNG > MODULATOR AND UPCONVERTER
(see Figure 11–2 or Figure 11–3).
Roll-Off Factor
ƒ 0.35
‚ 0.25
‚ 0.20
