SMD 989– User Manual
Page 37 (105)
Modulation/FEC: The modulations and supported code rates are shown in Figure 31. The
supported modes are selectable in the drop down list in the Modulation/FEC field. The listings will
depend on unit licensing and the selected mode in the Modulation Mode field at the top of the
menu.
Figure 31: Supported modulations & code rates for DVB-S/DSNG and DVB-S2
The remaining settings include (Bold indicates default):
Pilot Insertion (Only available in DVB-S2 Modes)
- Enable
- Disable
Description: When enabled, every 16 slots of 90 symbols the modulator will insert 36
non-modulated symbols to aid in receiver synchronization. The use of a pilot allows the
receiver to maintain carrier recovery, even when the user data payload cannot be
decoded.
Frame Size (Only available in DVB-S2 Modes)
- Normal (64,800 bits)
- Short (16,200 bits)
Description: Short frames introduce more overhead but give a shorter encapsulation
delay. Short frames are 4 time shorter than normal frames.
Spectral Inversion
- Normal
- Inverted