OPTICAL TRANSMISSION SYSTEM, OPTICAL TRANSMISSION DEVICE, AND WAVELENGTH INTERVAL MEASURING APPARATUS

摘要

PROBLEM TO BE SOLVED: To easily monitor a wavelength interval of a wavelength multiplex optical signal.SOLUTION: A received input signal obtained through digital coherent reception for a wavelength multiplex optical signal is converted from a time domain to a spectrum signal in a frequency domain, thereby, a wavelength interval of the wavelength multiplex optical signal is monitored on the basis of the spectrum signal.