C band erbium doped fiber amplifier as a flat gain optical amplifier

The most prevalent optical amplifier is erbium doped fiber amplifiers (EDFA) that has a wavelength dependent non-flat gain spectrum. Many configurations are used to flatten the EDFA gain. In this study, the fluctuant at the output signal gain depending on the input signal power was examined and it is shown that a C band EDFA can be used as a flat gain amplifier without a gain flattening tool.