Abstract: In order to analyze the gain characteristics of forward-pumped fibre Raman amplifier(FRA),comparison of two analysis methods—— both numeric simulation and analytical method is presented.At first,numeric simulation of the coupling equations of FRA was provided with Runge-Kutta method,and the effects of all parameters on gain of the amplifier were  investigated in detail.Then,based on the study before,numeric simulation method was compared with analytical analysis.It is discovered that:they are similar to each other under small signal,and analytical method is simpler;but numeric simulation is more adaptable to apply in characteristics analysis under big signal.

Key words: optical fiber communication, gain, fibre Raman amplifier, forward-pumped