Optical communication system with cascaded Raman amplifiers, each having multiple pump sources

摘要

The system has cascaded Raman amplifiers (V1,..), each with several pump sources (LD<1>1,..). The pump sources of at least two Raman amplifiers have different sets of wavelengths in order to achieve a flat gain spectrum for an optical signal (S) with several optical channels. Each Raman amplifier has a multiplexer for combining the pump signals of multiple pump sources.