Patent ID: 8625996

Claim:
An optical transmission system transmitting a wavelength multiplexed signal through a transmission line, the optical transmission system comprising: a time difference given signal generator which generates a time difference, and gives the time difference between an intensity modulation optical signal of a first channel and a phase modulation optical signal of a second channel different from the first channel both of which are included in said wavelength multiplexed signal; and a wavelength multiplexed signal output unit to which said intensity modulation optical signal and said phase modulation optical signal are input from said time difference given signal generator, and which generates and outputs a wavelength multiplexed signal in which said time difference was given between said intensity modulation optical signal and said phase modulation optical signal, wherein said time difference given signal generator comprises: a splitter to split said wavelength multiplexed signal into said intensity modulation optical signal and said phase modulation optical signal; and a time difference giving unit to give a time difference between said intensity modulation optical signal and said phase modulation optical signal split in said splitter, wherein said wavelength multiplexed signal output unit comprises a wavelength-selective switch, and wherein said optical transmission system comprises: an information collector to collect network management information on properties of transmission lines constituting a network to which said optical transmission system is applied, and about methods in which optical signals are modulated; and a controller to control wavelength selection that is performed in said wavelength-selective switch, based on said management information collected in said information collector.