Q-Lite Satellite Modem Installation and Operating Handbook
6-95
Figure 6-48 Rx Constellation Monitor
The Rx Constellation Monitor can be used to check for correct modem operation including
checking for signal distortion and phase noise. The persistence mode is useful for
showing any long-term effects due to phase noise and interference. Excessive phase
noise can cause cycle skips, seen as unwanted rotations within the constellation.
Note that MER and EVM figures are available on the panel on the right hand side. These
concepts are explained in the following information panel.
Modulation Error Ratio (MER) and Error Vector Magnitude (EVM)
MER and EVM (as displayed on the Rx Constellation Monitor)
measure how imperfect the received signal is in relation to an
ideal signal as in the following example.
Содержание Q-Lite
Страница 96: ...Q Lite Satellite Modem Installation and Operating Handbook 6 63 Figure 6 28 Edit IP Advanced Screen ...
Страница 146: ...Q Lite Satellite Modem Installation and Operating Handbook 6 113 6 4 2 Status Menu Figure 6 64 Front panel Status Menus ...
Страница 147: ...Q Lite Satellite Modem Installation and Operating Handbook 6 114 6 4 3 Edit Menu Figure 6 65 Front panel Edit Menus ...
Страница 233: ...Q Lite Satellite Modem Installation and Operating Handbook 12 11 Figure 12 2 PER for DVB S2 Short Frames ...
Страница 234: ...Q Lite Satellite Modem Installation and Operating Handbook 12 12 Figure 12 3 PER for DVB S2X Normal Frames ...
Страница 235: ...Q Lite Satellite Modem Installation and Operating Handbook 12 13 Figure 12 4 PER for DVB S2X Short Frames ...
Страница 237: ...Q Lite Satellite Modem Installation and Operating Handbook 12 15 12 14 4 DVB S DSNG Figure 12 7 BER for DVB S DSNG ...