OPTICAL AMPLIFICATION TRANSMISSION SYSTEM AND OPTICAL AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To improve the transmission characteristic by increasing number of multiplexed wavelength bands for wavelength division multiplex transmission. SOLUTION: A band compressor 20 that compresses a frequency band of signal lights subjected to wavelength division multiplex processing is placed to each pre-stage of optical amplifiers 18-1-18-3. A band expander 22 that expands a frequency band of a signal light subjected to wavelength division multiplex processing is placed to a poststage of optical amplifiers 18-1-18-3.