Optical transmission system has cascaded Raman amplifiers with several pump sources with different wavelengths set to achieve flat gain spectrum for signal with several optical channels

摘要

The system has cascaded Raman amplifiers (V1,..), each with several pump sources (LD11,..). 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.