OPTICAL COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To improve an OSNR and transmission characteristics of an optical communication system. SOLUTION: A first exciting light for Raman-amplifying a signal light and a second exciting light for Raman-amplifying the first exciting light are inputted from an optical multiplexer 5 arranged near an optical signal outputting part 8 to an optical signal to be inputted from an optical signal inputting part 6 to an optical fiber 7, and to be outputted from an optical signal outputting part 8 so that the Raman amplification of the signal light can be performed in the optical fiber 7.