Optical Power Budget Guide: Link Loss Calculation
Optical power budget is the maximum allowable loss in a fiber link. Calculate: Transmitter Power - Receiver Sensitivity.
Loss Components
Fiber: 0.35dB/km at 1310nm, 0.22dB/km at 1550nm. Connectors: 0.2-0.5dB per pair. Splice: 0.02-0.05dB. System margin: 2-3dB.
Example
10km fiber at 1550nm: 10x0.22 = 2.2dB. Connector pairs: 0.6dB. Splices: 0.1dB. Total: 2.2+0.6+0.1+3 = 5.9dB. Budget of 19dB, plenty of margin.
Tools
Use power meter and light source for loss testing. Use OTDR for precise measurements. Always document your calculations.
