Wavelength division multiplexing optical communication system and optical amplifying device

An optical amplifying device capable of collectively amplifying wavelength division multiplexed signal light from a wavelength division multiplexed signal light source, in which the output light of the optical amplifying device is controlled to be a predetermined output setting level, said optical amplifying device comprising:

• signal light output power controlling means for controlling the optical amplifying operation by correcting said predetermined output setting level based on a noise light power generated, so that signal light power per one wavelength included in the output light, is kept constant irrespectively of the number of wavelengths of signal light.

A wavelength division multiplexing optical communication system, comprising:

• at least one optical amplifying device capable of collectively amplifying wavelength division multiplexed signal light, the output light of said at least one optical amplifying device being controlled to be a predetermined output setting level;
• and
• a signal light output power controlling device controlling an operation of said at least one optical amplifying device by correcting the predetermined output setting level based on a noise light power generated in said at least one optical amplifying device, so that a signal light power per one wavelength included in the output light of said at least one optical amplifying device, is kept constant irrespective of the number of wavelengths of signal light.

An optical amplifying device capable of collectively amplifying wavelength division multiplexed signal light, in which the output light of the optical amplifying device is controlled to be a predetermined output setting level, said optical amplifying device comprising a signal light output power controlling device controlling the optical amplifying operation by correcting the predetermined output setting level based on the noise light power generated in said optical amplifying device, so that signal light power per one wavelength included in the output light of the optical amplifying device, is kept constant irrespective of the number of wavelengths of signal light.

An optical amplifying method for use with an optical amplifying device capable of collectively amplifying wavelength division multiplexed light, comprising:

• controlling an output light of the optical amplifying device to be a predetermined output setting level;
• and
• controlling the optical amplifying operation by correcting the predetermined output setting level based on a noise light power generated, so that signal light power per one wavelength included in the output light, is kept constant irrespective of the number of wavelengths of signal light.