
Q-Flex Satellite Modem Installation and Operating Handbook
7-36
If a DVB-S2-only service is required for an interface other than IP
then the Closed Network service should be selected, along with
the
SmartLink
FEC option. This will provide a DVB-S2 service with
no additional SCPC framing overhead. DVB-S2 with IP is
supported directly from the Tx and Rx service menu options.
Once DVB-S2 or
SmartLink
has been enabled, various other configuration menu options
become available, including choice of modulation and FEC rate, as well as DVB-S2 FEC
frame size choice and DVB-S2 pilots. DVB-S2 pilots introduce a regular burst of
unmodulated carrier that helps the demodulator lock onto the signal in poor signal-to-
noise conditions at a cost of increased overheads of around 2.4%.