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Q-Lite Satellite Modem Installation and Operating Handbook
6-18
Range:
5%, 10%, 15%, 20%, 25%, 35%
Description:
All spectral roll-off factors are available for all FECs with the
exception of DVB-S2 and
SmartLink
, which cannot be used with
roll-off factors less than 20%.
A comparison of the different spectral roll-offs, including their effect
on carrier power, is provided in the document ‘
Saving Satellite
Bandwidth by Optimising Spectal Roll-off
’. This is available from
the White Papers section of the Paradise web site at
http://www.paradisedata.com
.
Table 6-14 Tx/Rx Spectral Roll-off
6.2.4.15 Tx/Rx Spectral Inversion
Spectral inversion is an On/Off control that controls whether the carrier I and Q
components are swapped or not, allowing the modem to compensate for any other
equipment in the transmit or receive chain that has introduced a spectral inversion.
Paradise recommends keeping the signals in the space segment non-inverted,
particularly when
Paired Carrier™
is being used. If the ground-segment uplink
equipment contains a spectral inversion then transmit spectral inversion should be
enabled in the modem to correct for it. Similarly, if the ground-segment downlink
equipment contains a spectral inversion (e.g. due to an inverting LNB) then receive
spectral inversion should be enabled in the modem to correct for it.
6.2.4.16 L-band Output Power
Range:
0.0dBm to -30.0dBm; step size: 0.1dBm
Description:
This is the transmitted output power when using L-band.
Table 6-15 L-band Output Power
6.2.4.17 Modem/BUC Carrier
These allow the modem and BUC carriers to be switched on/off independently of each
other. BUC carrier control requires a control channel (i.e FSK or RS485) to exist between
the modem and the BUC.
6.2.5 Edit->Tx-Rx->Service->Advanced Screen
The
Edit->Tx-Rx->Service->Advanced
screen is shown in
Figure 6-6
.