An EDFA comprises three essential components: a segment of erbium-doped optical fiber, a laser diode serving as the pump source, and a wavelength -selective coupler that merges the pump light with the input signal for simultaneous propagation through the doped fiber. Booster (power) amplifiers: Boost power into transmission fiber, low NF, high Psat. An illustration of the effective gainis given below. Optical amplifiers have become the essential parts in all-optical. EDFA (Erbium-Doped Fiber Amplifier) is an optical device used to compensate optical signal attenuation caused by fibers and components, to increase optical transmission distance. While the EDFA gain saturation is predominately homogeneously broadened (i.