How to Calculate Fiber Optic Loss Budget
A fiber optic loss budget estimates the total signal loss in a fiber link. It sums cable attenuation, connector losses, and splice losses.
Total Loss = (Length x Attenuation/km) + (Connectors x Loss/Connector) + (Splices x Loss/Splice)
The power margin is the difference between the available power budget (TX power minus RX sensitivity) and the total link loss. A positive margin with at least 3 dB of safety is recommended.