Nera SatLink 1000, Руководство пользователя

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Nera SatLink Terminal User Guide – Revision P
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satellite (the carriers are those you expect). If the polarisation is not well aligned, you will also see the
carriers on the orthogonal polarisation.
Then, continue with the fine adjustment in elevation and azimuth. It is recommended that the span on the
spectrum analyser cover a single transponder. The resolution can be increased for the fine adjustment.
Coarse adjustment of the
antenna.
A frequency spectrum as seen
on the spectrum analyser.
Fine adjustment in elevation and azimuth observing one transponder.
.
If your measurement equipment can measure
BER, you can use this for adjustment. Select the
transponder you want to use. (In the example: IF
centre-frequency 1777 MHz or RF centre-
frequency 12.377 GHz).
The minimum BER without coding should be
better than 1E-4 and 1E-7 after Viterbi decoding
for QPSK. If you do not reach these figures, try to
re-adjust.