Using gain tilt for local compensation of unwanted power gradients
AssigneeNortel Networks Limited
InventorsBram Peeters, Nigel L. Bragg
Life of this patent
Estimating the term…
Abstract
A compensator for optical transmission systems exploits gain tilt inherent in optical amplifiers. The amount of SRS induced spectral power gradient is determined, and the amplifier gain is changed to cause a compensating gain gradient in the optical amplifier to compensate for the SRS induced spectral power gradient. Fewer components are needed, and so it can be less expensive. It can be implemented as a simple software upgrade to existing systems. Many such compensators can be distributed through the system, without requiring a large inventory of individually specified filters. More accurate compensation can be achieved by making it dependent on the distribution of wavelengths within a band.
Claims21
A compensator for use in an optical path of an optical transmission system, the system having at least one optical amplifier, the amplifier having a gain tilt characteristic, the compensator being arranged to determine an amount of unwanted spectral power gradient in the optical path, determine an amount of gain to cause a gain gradient in the optical amplifier to compensate for the unwanted spectral power gradient, the compensator also having a controller arranged to control the optical amplifier according to the determined amount of gain.
An optical amplifier for use in an optical path of an optical transmission system, the amplifier having a gain tilt characteristic, and having a compensator arranged to determine an amount of unwanted spectral power gradient in the optical path, and to determine an amount of gain to cause a gain gradient in the optical amplifier to compensate for the unwanted power gradient, the compensator also having a controller arranged to control the optical amplifier according to the determined amount of gain.
A compensator for use in an optical transmission system, compensator having:
- a detector arranged to determine an amount of unwanted spectral power gradient,
- a dynamic filter having a controllable wavelength response, and
- a controller arranged to control the wavelength response of the dynamic filter to compensate for the unwanted spectral power gradient.
A method of compensating for unwanted spectral power gradient in an optical transmission system having one or more optical amplifiers, the method having the steps of:
- determining an amount of unwanted spectral power gradient in the optical path,
- determining an amount of gain to cause a gain gradient in the optical amplifier to compensate for the unwanted spectral power gradient, and
- controlling the optical amplifier according to the determined amount of gain.
A method of offering a data transmission service over an optical transmission network having spectral gradient compensation using amplifier gain tilt.
Dependencies are inferred from the claim text.