Wavelength conversion system and wavelength conversion method

The embodiment of the invention provides a wavelength conversion system and a wavelength conversion method. Specifically, the wavelength conversion system comprises a first wavelength conversion module, a second wavelength conversion module and a third wavelength conversion module. Wherein the first wavelength conversion module and the third wavelength conversion module are used for carrying out cross-band wavelength conversion on an input optical signal, and the second wavelength conversion module is used for carrying out wavelength conversion in a band on the input optical signal. In different scenes, at least one wavelength conversion module can be selected from the three wavelength conversion modules to carry out wavelength conversion according to actual requirements, so that any wavelength conversion in a wave band can be realized, and any wavelength conversion across wave bands can also be realized. Therefore, the wavelength conversion system provided by the invention can realize any wavelength conversion in a wide spectrum range, and meets the requirements of a wide spectrum communication system in the future.