Theoretical Analysis of Rayleigh Backscattering Noise in Fiber Raman Amplifiers

摘要

＜正＞ In this paper,a new theoretical model for Rayleigh backscattering（RB）analysis of fiber Raman amplifiersis proposed.The model includes all the interactions among the pumps,signals,and all orders of RB.The results showthat the higher order Rb has a negligible influence on the performance of the amplifier.The co-propagating and counter-propagating RB power of the singal grow quadratically with the net-gain of the amplifier.The signal to double Rayleighbackscattering noise ratio(OSNRDRB)of backward-pumped FRAs is better than that of the forward-pumped ones athigh net-gain level（＞13 dB）,while at low net-gain level the OSNRDRBof the forward-pumped FRAs is slightly betterthan that of the backward-pumped ones.