| With the increasing use of the internet, digital business, remote education, information retrieval system, entertainment and community services etc, the needs to the speed and bandwidth of the information transmission line are more and more high. The impact to the world of the optical transmission system will be same as the internet. IP age will be the all optical net age. But the first generation of the WDM optical net can not meet the requirement in the aspect of the quality of the service, bandwidth, transmitted distance with no relay and net extending ability. The characterization of the optical net is based on the advancing of the optical components. As the most important component in the optical transmitting system, The gain of the Er Doped Fiber Amplifier (EDFA) is only cover the C and L band (1529～1561nm, 1570～1610nm), a fraction of the band of optical communication. The bandwidth of the transmission fiber is more than several THz. Raman fiber amplifier (RFA) is becoming more prospective with its character of the low noise and no limitation of bandwidth. It's the key node to the next generation of optical communication network. At the wideband communication system, the EDFA/RFA hybrid amplifier is the solvent way. The important technology of RFA is its pumping system.In this dissertation, the author presents the academic and experimental researches on a new Raman fiber Laser profile. And the researches involve diode laser collimation, thermal effect analysis of the crystal, mode matches of cavity and pumping of the 1342nm solid state Laser, the gain character of fiber based on the mode coupling equation, the resonator based on the fiber grating, modeling and simulation the dynamic process and main makeup parameter of Raman fiber Laser, experimental on the RFL, and so on.(1) Proposes a novel structure of 14xx nm Raman fiber Laser profile which based on the 1342nm solid state laser pumping. The 14xx nm fiber Laser output has been realized through the single Raman frequency shifting mechanism. It is a new, compact, high efficient and stable pumping source of RFA.(2) Based on the nonlinear mode coupling equation, the dynamic process of the stimulated Raman scattering signal power and pumping power evolvement has been modeling and simulating. The gain threshold condition, small signal gain coefficient and the gain saturation characteristics of the stimulated Raman scattering have been simulated. The researches on the gain character of three kind fiber has been experimentally done. The simulation tells that the length of the fiber and the pumping power are the main controlling factors for Raman gain and it also has been verified through experiment later.(3) Set a end pumping 1342nm solid state Laser. Under the profile of end pumping Nd3+:YVO4, firstly proposed a diode Laser collimated system which engages a pair of cylinder lens. The model of this collimator set on the ray trace theory. The designing and optimization way are created. The collimator has got the approving result same as the non-sphere cylinder lens.(4) The thermal lens effect of end pumped Nd3+:YVO4 solid state Laser has been studied. Based on the thermal conduct equation, the temperature distributing of radial and axial with the Guass beam profile pumping has been investigate. The thermal focus length can be estimated from a simplified model. The numerical solution of the thermal focus length of a working crystal is at the same order of the magnitude of measured.(5) Set a end pumping Nd3+:YVO4 Laser mode matching model under the theory of Laser cavity optics and ray trace. Design a way to control the laser cavity mode and the pumping beam waist. Through the simulation, the Laser structure parameter has been achieved and also been validated in the experimental system.(6) From coupling equation, the characteristic wavelength, the reflectivity, the bandwidth and especially the filtering character of the fiber grating has been investigated. The main discussion is the relevant problem of the fiber grating made cavity. According to the fiber laser condition, a pair of fiber grating which be used as laser resonator have been designed. The Laser longitudinal mode is also studied.(7) Set the dual-route Stock's single frequency shift Raman Laser mode coupling equation. The dynamic process of the Laser oscillating has been simulated. Based on the model above, the fiber length, the reflectivity of the output fiber grating and the pumping power has been optimized.(8) Constructs a 14xx nm Raman fiber Laser system. The experimental study is focus on the Laser actions related with the gain fiber length and the reflectivity of output coupling. The academic result matches the Laser with perfect.
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