Theory And Simulation Of High Power Double Cladding Erbium Ytterbium Co-Doped Optical Amplifier

In high power distribution system, the requirement of optical fiber amplifier with a higher saturation output power is needed. Erbium ytterbium co-doped double-clad fiber amplifier with cladding pumping technology couples the multi-mode high-power pump light into the double clad fiber's inner cladding, increasing the efficiency of the pump light absorption. Yb doping solutes concentration quenching problems caused by traditional high EDFA erbium ion concentration. Yb doping improves the efficiency of the pumping absorption effectively, which makes the 1550nm band high-power fiber amplifier become a research hotspot in the field at home and abroad.The article focuses a simulation study on the erbium ytterbium co-doped double-clad optical amplifier and fiber stimulated Brillouin scattering. Theoretical model of Er/Yb codoped double clad optical amplifier is established. Specific work is as follows:The development of domestic and international overview of optical amplifier is described. This paper studies the amplification of continuous light and pulsed light in Er-Yb codoped fiber amplifier. Stimulated Brillouin Scattering is also stydied in single-mode fiber. Under the condition of continuous light, newton iteration is used to work out the rate equations of particals. Fourth-order Runge-Kutta iterative method is used to work out transport equation of steady signal light, pumping light, Stokes and ASE light with forward pumping way. Different pump power and signal wavelength correspond different optimal fiber length to obtain the best gain. Different pump power correspond different optimal fiber length to obtain the best gain, which the setting value of the noise figure is not exceded. The relationship between signal power and ASE power is studied. The relationship between pump light and noise gain spectrum is studied. Stokes distribution along the fiber is studied. In the case of pulsed light, particle rate equations, signal light, pump, and ASE Stokes equations are solved using the finite difference method. The amplification of certain repetition frequency of the input rectangular pulse sequence is studied. The amplification characteristics of Rectangular pulse and Gaussian pulse is studied. In the single mode fiber, the stimulated Brillouin scattering of Gaussian pulse is studied. Appropriate length of fiber must be selected to avoid stimulated Brillouin Scattering.