Plan the optical budget before you build
Good planning of your optical network deployment is essential. When you plan with attenuation values measured in the field, you avoid signal budget risks, and the deployment costs less.
The 3 common mistakes to avoid in PON implementations
1. Use spliceable splitters in street enclosures and ODB boxes. Connectorised splitters look faster to install. After a year, most of our customers had spliced them anyway, because of reflections, dust and signal degradation. The spliced version pays off in fewer interventions.
2. Match the connector colour to the connector inside the device. If the ONU, OLT or EDFA has a blue margin, use a blue patch. Passing the signal from blue (SC-PC) to green (SC-APC), or the other way round, costs between 3 dB and 6 dB and raises the chance of a PON-wide back reflection. Blue goes with blue, green goes with green.
3. Turn the laser off before connecting a patch to an EDFA port. Without that precaution, three out of ten couplings damage the patch silently. Turn the laser off, or turn the EDFA off, while you connect the fibre.
PON optical budget calculator
The calculator estimates the level that reaches the subscriber. It counts splitter loss, 0.35 dB per kilometre of fibre, and 3 dB of tolerance for two connectors, splicing and other losses.