Research For Fiber Raman Amplifiers

With development of the optical fiber communication, DWDM emerges as the times require. Internet businessman desires the optical fiber transmission band to be broadened from C band to L band and S band, so the broadband amplification technique has become one of the fiber communication key techniques. Certainly, all kind of amplifiers are found. But the fiber Raman amplifier is the better one.Stimulated Raman Scatter serves as the principal of the fiber Raman amplifier, so its theoretical model is founded in the thesis to receive the express of SRS intensity at first. The express accounts enough for the characteristic of SRS. Secondly the gain coefficient is deduced by the express and the coupled model equation. Thus a new express about the gain coefficient is found from the parameters of the optical fiber and pump. Thirdly a new set of equation is put forward to discuss the manner of pump in optical Raman amplifiers. According as gain coefficient deduced, the design and experiment of gain flatten is brought into effect in addition. Finally the noise induced spontaneous Raman scatter is treated and their results accord with the experiments.