8-Gb/s-130 km transmission experiment using Er-doped fiber preamplifier and optical dispersion equalization

The authors report an 8-Gb/s lightwave transmission system operating at 1.53- mu m wavelength through 130 km of single-mode fiber having a chromatic dispersion of zero at 1.3- mu m wavelength. A receiver sensitivity of -34.2 dBm (365 photons/bit) was achieved using an erbium-doped fiber preamplifier pumped at 980-nm wavelength. A sensitivity of -31.9 dBm (620 photons/bit) was reached by a preamplifier pumped at a 1480-nm wavelength. By employing a Ti:LiNbO/sub 3/ external modulator and a fiber Gires-Tournois interferometer to equalize fiber chromatic dispersion, the penalty for 130 km transmission was held to only 0.9 dB.>