Abstract

To overcome the effects of fiber loss in a soliton-based communication system, optical amplifications using stimulated Raman scattering have been widely investigated. The idea is to input periodically along the fiber cw lasers with a slightly higher frequency compared with that of the signal. In a multichannel wavelength-multiplexing system, amplification parameters must be chosen carefully to compensate for the fiber losses in all channels. In this consideration, the Raman conversion among channels has to be taken into account. Here we consider a two-channel system and write two coupled equations in the sense that the net integrated gain is equal to the net integrated loss in an amplification period for each channel. By using an approximated curve for a Raman gain coefficient, those equations can be solved for deciding the required input pump intensity and wavelength. Numerical simulations have shown almost complete compensation for both channels if the amplification period is properly chosen. Also, the importance of the Raman conversion between two channels is clearly demonstrated.

© 1988 Optical Society of America