OPTICAL AMPLIFYING UNIT AND OPTICAL TRANSMISSION SYSTEM

摘要

An optical amplifying unit includes an input (101) for the input of optical signals, an output (102) for the output of the optical signals, a single-mode active fib er (103) codoped with Er and Yb, optically connected to the input and the output, and adapted to amplify the optical signals, a first pump source (104) for generating a first pump radiation including an excitation wavelength for Er, a second pump sour ce (106) for generating a second pump radiation including an excitation wavelength for Yb, a first optical coupler (105) for optically coupling the first pump radiation into the core of the active fibre in a co-propagating direction with respect to signa l direction, and a second optical coupler (107) for optically coupling the second pump radiation into the core of the active fiber in a counter-propagating direction with respect to signal direction. (Figure 9)