Managing gain tilt in an optically amplified transmission system
AssigneeTyco Telecommunications (US) Inc.
InventorStuart Abbott
Life of this patent
Estimating the term…
Abstract
An optical transmission system may include a combination of higher gain repeaters and lower gain repeaters, arranged to manage gain tilt. The higher gain repeaters and lower gain repeaters may be arranged to allow net gain to vary (e.g., above and below zero) within a predetermined acceptable net gain excursion. In one embodiment, the higher gain repeaters have a nominal gain value higher than a nominal span loss value and the lower gain repeaters have a nominal gain value lower than the nominal span loss value.
Claims26
An optical transmission system comprising:
- a plurality of higher gain optical amplifiers, each having a higher nominal gain value across a plurality of optical signal channels;
- a plurality of lower gain optical amplifiers, each having a lower nominal gain value across said plurality of optical signal channels lower than said higher nominal gain value;
- and
- a plurality of optical fiber spans coupling said optical amplifiers, wherein said higher gain optical amplifiers and said lower gain optical amplifiers are arranged to allow a net gain across said plurality of optical signal channels to vary within a predetermined acceptable net gain excursion at an output of each of said higher gain optical amplifiers and said lower gain optical amplifiers.
An optical transmission system comprising:
- a plurality of transmission spans coupled together, each of said transmission spans having a nominal span loss value across a plurality of optical signal channels and comprising a fiber optic cable span and an optical repeater coupled to said fiber optic cable span, wherein said optical repeater in each of said transmission spans has either a higher nominal gain value across said plurality of optical signal channels higher than said nominal span loss value or a lower nominal gain value across said plurality of optical signal channels lower than said nominal span loss value to allow a net gain across said plurality of optical signal channels to vary within a predetermined acceptable net gain excursion at an output of said optical repeater in each of said transmission spans.
A method for managing gain tilt in an optical transmission segment, said method comprising:
- determining a nominal span loss value for transmission spans in said optical transmission segment;
- providing a plurality of higher gain repeaters each having a higher nominal gain value higher than said nominal span loss value;
- providing a plurality of lower gain repeaters each having a lower nominal gain value lower than said nominal span loss value;
- and
- arranging said higher gain repeaters and said lower gain repeaters in said optical transmission segment such that a net gain at different points in said optical transmission segment-varies within a predetermined acceptable net gain excursion.
A method of constructing an optical transmission segment, said method comprising:
- determining a repeater spacing in said optical transmission segment based on a nominal span loss and nominal repeater gain substantially equal to said nominal span loss;
- providing a plurality of fiber optic cable spans corresponding to said repeater spacing;
- providing a plurality of higher gain repeaters each having a higher nominal gain value;
- providing a plurality of lower gain repeaters each having a lower nominal gain value lower than said higher nominal gain value;
- and
- connecting said repeaters to said fiber optic cable spans to form transmission spans, wherein said higher gain repeaters and said lower gain repeaters are arranged such that a net gain at different points in said optical transmission segment varies within a predetermined acceptable net gain excursion.
26-28. (canceled)
Dependencies are inferred from the claim text.