Abstract

The evolution of noise in transmission systems with multiple spans featuring forward pumped distributed Raman fiber amplifiers has been investigated experimentally and by numerical simulations. We found evidence that the transfer of relative intensity noise from the pump to the signal reveals characteristics of a nonlinear process, which cannot fully be captured by a Gaussian random variable added to the signal power. Power fluctuations of the pump radiation result in an intensity modulation of the amplified signal by stimulated Raman scattering. We have observed that a concatenation of multiple forward pumped amplifiers can lead to an increase of the bandwidth of the noise added to the signal compared to a single amplifier. A process acting like modulation instability of the pump radiation during propagation through the fiber was identified as a potential source of the bandwidth increase from span to span.

Analytical characterization of optical power and noise figure of forward pumped Raman amplifiers

Malin Premaratne
Opt. Express 12(18) 4235-4245 (2004)

Noise and transmission performance improvement of broadband distributed Raman amplifier using bidirectional Raman pumping with dual order co-pumps

M. A. Iqbal, M. Tan, L. Krzczanowicz, A. E. El-Taher, W. Forysiak, J. D. Ania-Castañón, and P. Harper
Opt. Express 25(22) 27533-27542 (2017)

Impact of input FBG reflectivity and forward pump power on RIN transfer in ultralong Raman laser amplifiers

Giuseppe Rizzelli, Md Asif Iqbal, Francesca Gallazzi, Paweł Rosa, Mingming Tan, Juan Diego Ania-Castañón, Lukasz Krzczanowicz, Pedro Corredera, Ian Phillips, Wladek Forysiak, and Paul Harper
Opt. Express 24(25) 29170-29175 (2016)

Low-noise Raman fiber amplifier pumped by semiconductor disk laser

A. Chamorovskiy, J. Rautiainen, A. Rantamäki, and O. G. Okhotnikov
Opt. Express 19(7) 6414-6419 (2011)

Relative intensity noise transfer of large-bandwidth pump lasers in Raman fiber amplifiers

Kafing Keita, Philippe Delaye, Robert Frey, and Gérald Roosen
J. Opt. Soc. Am. B 23(12) 2479-2485 (2006)