Numerical Modeling of S-Band EDFA Based on Distributed Fiber Loss

A numerical model for the analysis and design of S-band erbium-doped fiber amplifiers has been developed. The model is able to accurately predict the amplifier performances by taking into account the amplified spontaneous emission suppression due to the bending, as well as leakage losses of the fiber used as active medium. The model has been validated by comparing numerical and experimental data of bending loss, amplifier gain, and noise figure of an S-band optical amplifier based on a depressed-cladding erbium-doped fiber. A good agreement has been verified by varying fiber bending radius, input signal power, and wavelength. The model has been then applied to the optimization of the amplifier performances for wavelength-division multiplexer applications. The numerical results show that 20-25 dB gain can be achieved over a 25-30 nm range centered in a different part of the S-band from 1460 to 1525 nm, just by changing the bending radius and the length of a depressed-cladding fiber.