Q-Lite Satellite Modem Installation and Operating Handbook
6-19
Figure 6-6 Edit->Tx-Rx->Service->Advanced Screen
6.2.5.1 FastLink™ Optimisation Mode
The
FastLink optimisation mode
will be shown if
FastLink™
has been selected.
Balanced
Provides performance that is a good balance between low latency
and good BER performance. It is the best compromise between
trying to achieve the low latency of TPC and the BER performance
of conventional LDPC.
Low latency
Provides a lower level of latency that attempts to match or beat
that of TPC. This is at the expense of a small increase (typically
around 0.3dB compared to
Balanced
mode) in Eb/No required to
achieve a specific BER level.
Low BER
Provides better BER performance (typically reducing the Eb/No
required to achieve a particular BER level by around 0.3dB
compared to
Balanced
mode) at the expense of higher latency.
Latency halves as data rate doubles so this mode is suitable for
applications that are not latency sensitive and for higher data rate
applications (nominally 2Mbps and above).
Table 6-16 FastLink™ Optimisation Mode
6.2.5.2 DVB-S2 Tx/Rx Pilot Tones
Pilots are an On/Off control that controls whether DVB-S2/S2X pilots, which are
unmodulated symbols, are injected into the carrier on a regular basis in order to help the
demodulator lock onto the carrier. The pilots are 36 symbols long and are injected every
1440 symbols, representing an additional overhead of around 2.4%.