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www.TELE-satellite.com —
02-03/2012 —
TELE-satellite International — The World‘s Largest Digital TV Trade Magazine
we were able to build
a small network us-
ing only their compo-
nents. All components
were perfectly finished
off and the splitters
were clearly labeled.
You will not have any
doubt how to hook
them up. In contrast
to the RF stuff with F
type connectors, you
do not have to hurt
your fingertips when
connecting everything
together in fiber op-
tic installations. Just
a delicate push, you
hear a click and a fiber
optic cable is connect-
ed to a splitter. Now
you may guess why
Huber+Suhner brand-
ed their new system
CLIK!
TELE-satellite read-
ers more familiar with
insertion losses ex-
pressed in decibels
rather than the signal
power percentage de-
scription of the splitter
outputs may at first
feel slightly uncom-
fortable. But take it
easy. One corresponds
precisely to the other.
We can easily convert
original
percentage
values to familiar “tap
loss” and trunk “loss
figures” in decibels -
see the table.
We spent some time
wondering what to
measure to make our
test results as practi-
cal for our readers as
possible. We decided
to measure rather the
RF signal that will be
fed to the receiver IF
input than optical sig-
nal before and after
a fiber optic splitter.
In this way, you have
a good idea what you
can expect from the
whole system in which
Huber+Suhner CLIK!
Splitter Box is used.
Our test system in-
cluded: 90cm dish
aimed at HOTBIRD sat-
ellite on 13° E, an opti-
cal LNB, optic fiber ca-
ble, optic splitter and
optic-to-RF signal con-
verter (re-modulator)
that was delivering the
IF signal suitable for a
satellite receiver. The
optical LNB generated
light in the 1310 nm
band. The light car-
rier was modulated
with 0.95-5.45 GHz RF
signal which was Ku-
Band low and high sub
bands of both polariza-
tions stacked one over
the other.
We tested 5 CLIK!
Splitter Box models.
The table below pre-
sents the insertion
losses specified in
manufacturer data.
You can see the re-
sults in the attached
graphs. Please mind
that on top of the optic
splitter losses, there
are losses caused by
nonlinear
transfer
function of the optic-
to-RF signal converter.
Because of that, the
losses for 10, 20 and
30% outputs may ap-
pear slightly higher
than specified for cer-
tain frequencies. This
is due to non ideal
optic-to-RF conversion
- not because of op-
Download this report in
German
www.TELE-satellite.com/
TELE-satellite-1203/
deu
/huber+suhner.pdf
tic splitters imperfec-
tions.
We also measured
the noise performance
and we are happy to
inform you that in
line with theory, op-
tic fiber cable and op-
tic splitters practically
do not add any noise.
No matter what out-
put we tested: 90% or
10% MER or C/N read-
ings were at maximum
(MER was above 14
dB). This means that
your receiver connect-
ed to such network
would also show very
high quality readings
(close to 100%).
Using
a
prop-
er combination of
Huber+Suhner CLIK!
Splitter Boxes, you can
easily build a distribu-
tion network with even
36 optic outputs pro-
vided that your optic
LNB generates about
7 dBm of output power
what is a quite typical
value. Such configura-
tion consists of one 1x4
splitter which splits
the LNB output to four
optic fiber cables. On
every fiber optic cable,
eight 1x2 splitters are
installed: four 10/90,
two 20/80, one 30/70
and one 50/50. In such
configuration, you get
the output levels from
-10.7 dBm through
-13.2 dBm. This is
quite a sufficient level
for an optic-to-RF con-
verter. Now, if your
optic-to-RF converters
are of quad types, you
will be able to connect
not 36 but 144 regular
satellite receivers!
After taking our
measurements, we can
honestly confirm that
this is not just theo-
retical possibility but
something that can be
realized in real world.
Time has indeed come
to focus and switch to
the fiber optical world.