| With the fast development of Internet and other data communication, the capability demand of long-haul fiber communication system is increasing dramatically. Fiber Raman Amplifier has the characters of wide-band, using transmit-fiber as gain medium and excellence noise performance, therefore it gets more and more attention. In this thesis, some theoretical analyses of fiber Raman amplifier are given. And with the method of numerical analysis, an arithmetic method which can run in computer is developed from the mathematics' model of gain process of FRA. Then software for FRA's simulation is particularly designed to meet the demand from users. Finally the results of experiment and simulation in the same condition is compared and analyzed. The analysis shows that the software can well meet the demand of simulation of FRA experiment. The main research contents and results are given as follows:The characters of several kinds of optical amplifiers are compared. And the properties, applications and developments of fiber Raman amplifier are recounted.The basic theory of Raman scattering and the characteristics of stimulated Raman scattering in fiber are detailed. The properties of fiber Raman amplifier, such as gain property, noise property, polarization correlation and temperature stability, are discussed.The mathematics' model of fiber Raman amplifier is given at first. Then based on the model, an arithmetic method to simulate gain process of FRA is produced. And as the initial value is the key problem for simulation, different methods to get initial value in different pump-type conditions are detailed. The methods to fit gain curve of fiber and to get noise coefficient are also proposed.The operation principle and function of the pump light source,Raman fiber and passive components, which buildup the FRA communication system, are introduced. And the functions of these devices are expressed in terms of corresponding figures and formulas.With the application of software engineering, the design of FRA simulation software is particular described. The static structures and dynamic situations of software are illustrated by Unified Modeling Language (UML). Then the software is used to simulate FRA experiment. In the experiment, two pumps with both wavelengths of 1428nm and 1455nm are adopted to course C-band amplification. Finally, after a contrast between the results of simulation and experiment, the gain curve of simulation can be found similar to the experiment, and the differences between the gain values of simulation and of experiment in any wavelength do not exceed 1dB. It is showed that the software can be applied to the simulation work in FRA experiment well.
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