The short answer: A 1×2 splitter introduces ~3. Let's say you have a laser output at 0 dBm (which is 1 milliwatt of optical power). 5 dBm This means each output port now only carries about 0. Your total link budget must also account for fiber attenuation (0. in Watts – W), the loss value in dB is calculated by the formula: Loss (dB) = 10 lg ( mW1 / mW2 ) When both gains are equal, the loss is 0 dB, so there is no loss (doesn't happen obviously). If we operate with absolute gains measured in relation to 1. Free guided onboarding - Validate your first OLT-to-ONU plan with our team. multiple losses in cascaded systems. This extends the maximum distance between OLT and ONT.