Design Of Variable Gain Erbium Doped Fiber Amplifier Based On Super C Band

With the growth of network traffic,the performance requirements of dense wavelength division multiplexing for communication services are getting higher and higher.In order to improve the transmission efficiency,the transmission spectrum is gradually extended to C+L Band transmission.Super C Band transmission come into being.Many companies in China and abroad begin to develop relevant devices for the Super C Band transmission system.Due to the development of the Internet,the demand for amplifiers in the data center is gradually diversified.It requirs amplifiers with wider gain bandwidth and more flexible gain spectrum.Aiming at the new band of Super C Band,this thesis innovates the traditional EDFA.This thesis adds a three-stage pumping mechanism on the basis of the current popular two-stage pump amplifier,and designs an EDFA that can adjust the gain in Super C Band under the premise of changing the input light.It expands the amplification spectral width by 15 nm,and adds the gain adjustment function,which is more suitable for 5G transmission,optical fiber communication between data centers and other occasions.So,amplification of Super C Band is necessary for the spread of spectrum.This thesis mainly focuses on the following aspects of Super C Band EDFA:(1)The basic principle of EDFA is described.Based on Giles model and rate equation,the amplification mechanism of Super C Band is preliminarily analyzed.(2)OASIX simulation software is used to analyze the pump wavelength,erbium fiber length,pump mode,pump power and other parameters of MP-980 erbium-doped fiber;The structure of three-stage pumped EDFA is preliminarily designed,and the parameters of the amplifier are optimized according to the evaluation index of EDFA.The optimal length of erbium fiber and pump power of each stage are obtained,and the corresponding gain flattening filter is designed to reduce Ripple to less than 0.1d B.(3)Analyze the insertion loss of the actual device,adjust the erbium fiber length,and adjust the pump DAC current and VOA according to the actual gain spectrum to make the gain spectrum reach the design level.The experiment proves that 7.5d B～26d B adjustable gain can be achieved by adjusting the pump power and adjustable attenuator in the range of-25 d Bm～-9.8d Bm of incoming light.