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09-10/2012
Global Invacom System
Finally a system to build really large
distribution nets without having to care at all
about attenuation
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TELE-satellite International — The World‘s Largest Digital TV Trade Magazine
— 09-10/2012
— www.TELE-satellite.com
The Battle Is Over and
Fiber Has Won
TEST REPORT
Fibre Optic Distribution System
The carrier-to-noise ratio
is one of the major concerns
when designing large sys-
tems to distribute satellite
tv signals. When you have
to deal with long coaxial
cables and/or many signal
splitters, your signal qual-
ity degrades significantly.
To keep it good enough for
the most peripheral users,
you have to minimize the
number of signal splitter be-
tween the LNB and the very
last receiver and keep the
total cable length as short
as possible. You also need
to install quite a large dish
and low noise LNB to ensure
high carrier-to-noise ratio at
the input of the distribution
system. However, this may
not work well enough for re-
ally large systems.
What then? Until recently,
you had no choice but to in-
stall additional large dishes
and LNBs and build several
separate distribution sys-
tems. Of course, this is not
a welcome solution. It adds
complexity, cost and the an-
tenna farm on the roof does
not make (normal) people
happy. But now GlobalInva-
com comes to our rescue.
Thanks to their innovative
solution based on fiber optic
cables and optical splitters,
building even very exten-
sive networks becomes easy
and manageable.
In order to switch from
coax cable to fiber optic
cable, the very first thing
needed is the conversion of
the electromagnetic waves
coming from a satellite (or
from a DTT transmitter) to
modulated light that can be
then distributed over fiber
optic cables. TELE-satellite
readers remember that we
already introduced Glo-
balInvacom’s FibreMDU Uni-
versal Optical LNB. We first
reported about this innova-
tive LNB in TELE-satellite
04-05/2008 and in a follow-
up story in TELE-satellite
08-09/2009. But this time,
we had the opportunity to
test something else. It was
the FibreIRS LNBm whole-
band LNB with integrated
frequency stacker.
The FibreIRS LNBm is
installed in place of an or-
dinary LNB but it does not
output signal in the familiar
0.95 – 2.15 GHz frequency
range. And it does not re-
The FibreIRS LNBm mounted on a 90cm dish
