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System functions
Digital terrestrial and satellite signals are fed to the optical transmitter (OSC 100 micro)
which converts the electrical signals into optical signals, thus allowing distribution over
long paths using a fi bre-optic infrastructure.
Suitable splitters (OVC xxx) and taps (OAC xxxx) are available for distribution of the opti-
cal output signal.
Notes on planning the fi bre optic system
When designing a fi bre optic system, it is important to consider the optical input levels to
the receiver (OEC 40 micro or OEC 44 micro). To ensure that the system fulfi ls the required
parameters, appropriate attenuation must be calculated at each point. The optical output
power from the transmitter (OSC 100 micro) is typ7 dBm. The input level of the op-
tical receiver (OEC 40 micro and OEC 44 micro) lies between -8 dBm and -14 dBm. This
results in an allowable attenuation of the optical network of 15 to 21 dB.
The catalogue contains a whole range of optical attenuators and taps/splitters which have
different attenuation values and enable the optimisation of the system. Please use the
Kathrein CLIKulator to plan and adjust your optical distribution network
(http://clikulator.com/kathrein).
• If directly connected without splitters or taps, attenuators must be used
between the OSC 100 micro and OEC 40 micro/OEC 44 micro. To avoid
overload, the input power on the receiver must not surpass -8 dB.
• If the quality of an input signal is not optimal or if a multi-carrier signal
must be distributed over a large coaxial distribution network, the optical
budget should be decreased.
• The level difference of a satellite transponder polarity (VL/VH/HL/HH)
should not exceed 4 dB. If the transponders have a gain slope on the
inputs of the OSC 100 micro and the level is high enough, you can use
the passive equalizer ERZ 60 in certain circumstances to adjust the
level (use one ERZ 60 for each satellite polarisation). If a long coaxial
cable is used between the LNB and the OSC 100 micro, you can adjust
the level and the gain slope (for each satellite polarisation) with the VWS
2500. If several transmitters (OSC 100 micro) are cascaded, a VWS
2500 satellite distribution amplifi er must be connected between the
third and the fourth OSC 100 micro and also between the fi fth and sixth
in the cascade. The maximum quantity is seven in the OSC 100 micro
cascade.
