Work out optical power margin instantly with clear inputs, formula shown and shareable results.
The optical budget is the transceiver's output power minus its receive sensitivity, and the margin is what remains after subtracting measured link loss and an allowance for ageing, connector degradation and future repair splices. A margin below about 2 dB means the link will fail as connectors get dirty or the plant is repaired.
Optical margin
budget = Tx power - Rx sensitivity; margin = budget - link loss - ageing allowance; received power = Tx - link loss
Yes. Exceeding the receiver's overload threshold causes errors just as surely as too little power, which is why short links sometimes need an attenuator.
Connector contamination, additional repair splices over the cable's life, temperature variation and transceiver output decline. Three dB is a common figure.