Method and apparatus for adjusting tilting and level of optical signals
AssigneeSiemens Aktiengesellschaft
InventorErich Gottwald
Life of this patent
Estimating the term…
Abstract
Pump energy with a wavelength which is below the wavelength of an optical signal is fed into a transmission section from a pump laser via a coupler. The received optical signal is attenuated with increasing pump power with signals having higher frequencies being more strongly damped.
Claims25
A method for adjusting tilting of a broadband optical signal transmitted via an optical transmission fiber through injecting pump signals into the optical transmission fiber, the method comprising:
- transmitting a plurality of transmission bands via the optical transmission fiber;
- measuring signal levels of each of the plurality of transmission bands;
- injecting at least one pump signal and at least one further pump signal into the optical transmission fiber to add or subtract energy to and from a signal using a Raman effect when at least two signal levels of the measured signal levels of at least one of the plurality of transmission bands are changed or absent from the transmitted broadband optical, the at least one pump signal having a wavelength less than a minimum wavelength of each of the plurality of transmission bands and the at least one further pump signal having a wavelength that is greater than a maximum wavelength of each of plurality of transmission bands;
- and
- selectively setting a power level for a chosen wavelength of at least one of the at least one pump signal and the at least one further pump signal such that the tilting of a transmission band, in which signal levels do not change, remains at least substantially constant at a receiving end of the optical transmission fiber.
A method for adjusting tilting of an optical signal transmitted via an optical conductor through injecting a plurality of pump signals into the optical conductor, the method comprising:
- transmitting a plurality of transmission bands via the optical conductor;
- measuring signal levels of each of the plurality of transmission bands;
- injecting at least one pump signal into the optical conductor when an absence of a signal level from the transmitted broadband optical signal of the measured signal levels in a transmission band of the plurality of transmission bands occurs;
- and
- setting a level of at least one pump signal such that the tilting of a transmission band in which the absence of the signal level does not occur remains at least substantially constant at a receiving end of the optical conductor causing said tilting;
- wherein a pump wavelength of a pump laser used to compensate an absent transmission band corresponds to a mean wavelength of the absent transmission band.
An apparatus for adjusting tilting and level of an optical signal transmission via an optical transmission fiber comprising:
- at least first and second pump lasers that respectively inject at least first and second pump signals into the optical transmission fiber to add or subtract energy to and from a signal using a Raman effect, the first pump signal having a wavelength less than a minimum wavelength of the optical signal transmission and the second pump signal having a wavelength that is greater than a maximum wavelength of the optical signal transmission;
- and
- a controller for measuring at least two signal levels of one of at least two transmission bands, and selectively adjusting a power level for a chosen wavelength of the first and second pump signals when said at least two measured signal levels of at least one of the plurality of transmission bands are changed in the transmitted broadband optical signal causing said tilting, wherein the tilting of a transmission band in which signal levels do not change remains at least substantially constant at a receiving portion of the optical transmission fiber.
An apparatus for adjusting tilting and level of an optical signal transmission via an optical conductor comprising:
- at least one pump laser that injects pump signals into the optical conductor;
- and
- a controller for measuring at least two signal levels of one of at least two transmission bands, and adjusting a power level of at least one of the respective pump signals when said at least two measured signal levels of at least one of the plurality of transmission bands are changed in the transmitted broadband optical signal causing said tilting, wherein the tilting of a transmission band in which the absence of the signal level does not occur remains at least substantially constant at a receiving end of the optical conductor;
- wherein a pump wavelength of the at least one pump laser used to compensate an absent transmission band corresponds to a mean wavelength of the absent transmission band.
Dependencies are inferred from the claim text.