Patent ID: 6603598
Filing Date: 2003-08-05
Classification: H01S,H04B

Abstract:
Optical transmission system comprising:an optical transmitting unit (10) for transmitting optical signals, an optical receiving unit (20) to receive said optical signals, an optical fiber link (30) optically coupling said transmitting unit to said receiving unit and adapted to convey said optical signals, and an optical amplifying unit (100) coupled along said link, adapted to amplify said optical signals; said optical amplifying unit (100) comprising: an input (101) for the input of said optical signals, an output (102) for the output of said optical signals, an active fiber (103) having a core codoped throughout with Er and Yb, and having a first end (103a) optically coupled to said input (101) and a second end (103b) optically coupled to said output (102), for the amplification of said optical signals, a first and a second pump source (104, 106) for generating a first and, respectively, a second pump radiation, and a first and a second optical coupler (105, 107) for optically coupling said first pump source (104) and, respectively, said second pump source (106) to said active fibre (103), characterized in that said first pump radiation includes an excitation wavelength for Er and said second pump radiation includes an excitation wavelength for Yb, and the first pump radiation and the second pump radiation are fed throughout the core to excite Er and Yb, respectively.