Individual versus end-to-end gain equalization in erbium-doped fiber amplifier chains: a comparison

Gain equalization of erbium-doped fiber amplifier (EDFAs) is an important problem in lightwave communication systems. We compare two approaches for gain equalization. The two strategies are compared quantitatively by considering power budget, received signal power and signal-to-noise ratio (SNR), and transmission distance. Relative performance is shown as a function of the number of amplifiers and the number of channels, we also consider relative technical advantages of implementing the two equalization schemes. It is shown that as number of channels increase, depending on the number of channels transmitted, the individual equalization scheme results in a 500 km-1000 km increase in transmission distance relative to the end/end equalization scheme at the expense of a more complex and expensive implementation. The results provide an insight into the relative merits of end/end versus individual electronic equalization strategies