Measurement technique for pump and signal background absorption of erbium-doped fibres

An explicit analytical expression for the transmission of pump and signal power through an erbium-doped fibre in the presence of background loss is given. Because the solution is explicit, it can easily be fitted to measurement results. This leads to a simple method For determining the erbium absorption constant, saturation power and fibre background absorption constant. The technique is demonstrated for wavelengths of the signal range