TWO-STAGE MODULAR WIDE-BAND OPTICAL AMPLIFIERS

摘要

A modular architecture for a unidirectional fiber amplifier provides separate optical amplification for a short and long band transmission channels of a wide-band optical signal. The modular amplifier comprises a first gain stage that amplifies the short band and passes through the second-band, and a second gain stage connected in series with the first gain stage that amplifies the long band. The short band by-passes the second stage. The length of the doped fiber and the population inversion of active fiber of the first stage are selected to give an average inversion in excess of about 50%, while the length of the doped fiber and the population inversion of active fiber of the second stage are selected to give an average inversion in excess of about 50%.