Analytical model for the calculation of the optical signal-to- noise ratio (SNR) of WDM EDFA chains

A new, simplified analytical model for the calculation of the signal-to-noise ratio (SNR) in multiwavelength erbium-doped fibre amplifier (EDFA) cascades is presented. Comparisons with numerical results give excellent agreement, confirming the validity of this model and its significance for optimising system parameters.