TELNET GPONDoctor 9500, User Manual

Page: 18 / 105

GPONDoctor 9500
User manual
200080279-00 GPON DOCTOR 9500 user manual EN v0 WEB
18
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 Tables 1 and
2 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 optical splitting module connectors of GPON
Doctor™ 9500.
Figure 9 GPON Doctor™ 9500 splitter where the attenuators might be added.
1. Introduces attenuation
Connection of the optical splitting module to the PON network