TELNET GPONDoctor 9500, User Manual

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GPONDoctor 9500
User manual
200080279-00 GPON DOCTOR 9500 user manual EN v0 WEB
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Power in Upstream direction: As there is only one ONT connected to the GPON
Doctor™, the power meter will have to measure the optical power between the
ONT and the GPON Doctor™.
The obtained results are an approximate value of the power from each of the directions
at the target capture point.
Calculation of the necessary attenuation
The optical receivers of the capture card have a range of operational power levels that
must be respected. An excess or deficit of power would cause a loss of information or
capture errors.
The calculation of the attenuation must employ the following criteria for each direction
of the communication:

If the measured power is less than the sensitivity value envisioned in Table 1 for
the splitting module, the capture is probably not executed with guarantees. Under
that condition, it is recommended to select another target capture point within the
PON where the power budget is higher. Alternatively, optical amplifiers could be
used at the “Entry from OLT”.

If the optical power measured is greater than the saturation value envisioned in
Table 1 for the splitting module, the attenuation required has to be greater than
the difference between the value measured and the saturation value. For example,
a value measured of 5dBm at the “Entry from OLT” is 4.5dB over the saturation
value (+0.5dBm), therefore an attenuator of minimum 4.5dB is needed at the
“Entry from OLT” connector.
Attenuation of excess optical power
Once the required attenuations have been calculated for each direction of the
communication, they must be added to the connectors of the capture card. Attenuations
must never be inserted into the optical splitting module connectors.
Figure 11 GPON Doctor™ 9500 splitter where the attenuators might be added.
1. Introduces attenuation