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TELE-satellite International — The World‘s Largest Digital TV Trade Magazine
— 09-10/2012
— www.TELE-satellite.com
ly sensitive instrument - ca-
pable of processing even
such weak signals. We mean
signals with a MER of 5.5 dB
and less. It corresponds to a
C/N below 8 dB. Such tran-
sponders are hardly receiv-
able by regular receivers.
The optical system we
built had FibreIRS LNBm in-
stalled on the same 90 cm
dish, FibreIRS ODU32, 100
meters of fiber optic cable,
Spit2-OFpro, another 100
meters of fiber optic cable,
Spit4-OFpro, another 100
meters of fiber optics ca-
ble and FibreMDU to which
we connected the satellite
signal analyzer. As you can
calculate, the system had in
total 300 meters of fiber op-
tic cable and two splitters in
series.
The results were really
astonishing! The optical
system was able to deliver
almost all transponders we
had with a classical system
except for the two weakest
transponders (12577HH and
12618HH). As we said be-
fore, those two transpond-
ers were below the recep-
tion threshold of a regular
receiver anyway. So, in fact,
we did not lose anything. All
the remaining transponders
were significantly stronger
in the optical system. MER
was at par with the classi-
cal system. This means that
signal quality did not de-
graded despite 300 meters
of cable and two splitters!
You can see our results on
the attached graphs.
After the first round of
measurements, we changed
the output of Spit2-OFpro
splitter and did the second
run for the optical system.
And finally, we changed the
output of Spit4-OFpro split-
ter and repeated the meas-
urements. As you can see,
there was practically no dif-
ference in performance what
proves that all outputs of
the splitters produced very
similar signal. (graph.1, 2)
All the GlobalInvacom
components we tested were
perfectly finished off and we
had absolutely no problem
in making the connections.
Just click, click, click and
everything was connected.
All optical and RF connec-
tors of the devices had pro-
tective covers so that no
dirt could access it during
transportation or the in-
stallation process. Building
such optical system was like
playing with LEGO blocks. It
was nothing but joy.
If we connected more
fiber optic cables, splitters
and converters, we could
deliver exactly the same
signal as presented on our
graphs to not fewer but 64
satellite receivers. And all
this from a single dish and
single FibreIRS LNBm. If we
used even more splitters
or Spit4-OFpros in place of
Spit2-OFpros, the number
of end users would be much
greater. The only thing one
can expect then is some-
what lower output power