Two-stage high-gain optical amplifier

Abstract
A two-stage semiconductor optical amplifier is discussed. Net fiber-to-fiber gains as high as 36.5 dB have been achieved. When used in a fiber-optic transmission system, using a commercial 1.7 Gb/s regenerator, the fiber span between transmitter and regenerator is increased to 151 km and 1.3 mu m wavelength. With a 1.55 mu m two-stage amplifier, a transmission distance of 180 km at 3.4 Gb/s is demonstrated.