Wavelength division multiplex transmission system

An optical transmitting apparatus for transmitting optical signals having different wavelengths by using a wavelength division multiplex technique, comprising:

• a transmitting section that uses an electrical-optical converter for generating an optical signal having therein a monitor signal multiplexed with a data signal to be transmitted and having wavelength chirp due to the monitor signal;
• a wavelength multiplexer for multiplexing the optical signal generated by the transmitting section with another optical signal having a wavelength different from a wavelength of the optical signal;
• a control signal generator for generating a control signal based on the monitor signal included in the optical signal after a desired wavelength is extracted based on a transmission characteristic of the wavelength multiplexer;
• and
• a wavelength controller for controlling, based on the control signal, a wavelength of light output from the electrical-optical converter.

An optical transmitting method for transmitting optical signals having different wavelengths by using a wavelength division multiplex technique, comprising:

• generating, by using an electrical-optical converter, an optical signal having therein a monitor signal multiplexed with a data signal to be transmitted and having wavelength chirp due to the monitor signal;
• transmitting the generated optical signal via a wavelength multiplexer, an optical transmission path, and a wavelength demultiplexer;
• generating a control signal based on the monitor signal included in the optical signal after a desired wavelength is extracted based on a transmission characteristic of the wavelength multiplexer or the wavelength demultiplexer;
• and
• controlling, based on the control signal, a wavelength of light output from the electrical-optical converter.