Common attenuation rates are 0. 2 dB/km for single-mode fiber at 1550nm and 0. Connector loss (dB) = number of connectors × loss per connector. Total loss = cable loss + connector loss. It is often the case to calculate the maximum signal loss across a given fiber link during optical cable installation. First, you should be aware of the fiber loss formula: The Total Link Loss = Cable Attenuation + Connector Loss + Splice Loss Cable Attenuation (dB) = Maximum Cable Attenuation. The power budget refers to the amount of fiber optic cable plant loss that a datalink (transmitter to receiver) can tolerate in order to operate properly. Sometimes the power budget has both a minimum and maximum value, which means it needs at least a minimum value of loss so that it does not. This chart illustrates how total fiber loss (blue) increases with fiber length, showing the contribution from fiber attenuation (green) versus fixed losses from splices and connectors.
[PDF Version]