They first were observed in a boat canal in 1834 and now are used in opticalfibercommunications.
它们在1834年在一条运河船中被观察到,现在被用于光纤通讯。
2
The implement applications of erbium doped fiber amplifier (EDFA) and fiber Raman amplifier (FRA) make the launching power in opticalfibercommunications systems increased significantly.