Structure Optimization Of Er/Yb Co-doped Fiber Amplifier

As the rapid development of communication technology, fiber amplifier has become increasingly widely used in the DWDM transmission system, fiber optic CATV and fiber access networks. Pump coupling is one of the key technologies of fiber amplifier. Multi-pump technology which developed based on the side-pumped technology can improve the gain and balance of amplifier.This paper mainly studied the application and structural optimization of multi-point pump in erbium/ytterbium co-doped fiber amplifier (EYDFA). First, using positive approach single-stage pump of EYDFA as the prototype, we analyzed the impact of variable pump power on the amplifier gain; second, by analysis and comparison, a suitable one for multi-point coupling from the wide variety of side-pumped coupling technology was selected; meanwhile, we studied the gain variation of the multi-pumped high-power laser in different situation, which provided a direction for optimization of the multi-pumped fiber amplifier. Finally, on the basis of the prototype we designed a multi-pumped amplifier structure which made the gain increased by nearly 2dB comparing with the prototype. On this basis, by determining the interval between the pump and adjusting the distribution of the three pump power,the structure of multi-point erbium/ytterbium co-doped fiber amplifier was optimized. Experimental results show that comparing with the initial multi-point pump model, the gain of the optimized model increased by nearly 1dB.