Performance Improvement of Gain in Distributed Raman Amplifier Using Forward and Backward Pumps

摘要

Optical amplifiers have played a revolutionary role in fiber communication systems from early 1990s itself. An optical signal can be amplified within the optical domain without converting to electrical domain using optical amplifiers in an inexpensive way without electronic regenerators. The fiber itself acts as the gain medium for distributed Raman amplifier. The working principle of Raman fiber amplifier is called stimulated Raman scattering (SRS), which is a nonlinear effect and it requires an optical power higher than a threshold of at least 500 mW [1]. An input signal can be amplified while traveling through the fiber in the same direction or in opposite direction with a pump wavelength of appropriate power. By carefully adjusting the forward and backward pump power, the transmission performance can be improved. In this paper, the gain and SNR of the amplifier are studied for different pumping schemes and found that the transmission performance is improved by operating on low pump power ratio which does not require any changes in the existing system.