Optical amplifier and gain tilt compensation method
AssigneeFujitsu Limited
InventorsMasato Nishihara, Yasushi Sugaya, Etsuko Hayashi
Life of this patent
Estimating the term…
Abstract
The optical amplifier realizes EDFA amplification of optical signals in new bands (the S+- and S-bands), at wavelengths of 1450 to 1530 nm. The amplifier uses multiple erbium-doped fibers to amplify optical signals at wavelengths of 1450 to 1530 nm. Each of the multiple optical filters is interposed between the individual erbium-doped fibers. The sum of the transmission characteristics of the multiple filters is identical to an inverted EDF wavelength gain characteristic at wavelengths of 1450 to 1530 nm which is then shifted to the direction that the transmission increases.
Claims34
An optical amplifier which amplifies optical signals at a range of wavelengths from 1450 to 1530 nm, said optical amplifier comprising:
- a plurality of erbium-doped fibers;
- and
- a plurality of optical filters, each of which is interposed between the individual erbium-doped fibers, said optical filters are configured so that a total of the transmission characteristics, which is a sum of the transmission characteristics of each of said optical filters, is obtained by inverting a wavelength gain characteristic of said erbium-doped fibers in the 1450 to 1530 nm band and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases.
An optical amplifier which amplifies optical signals at a range of wavelengths from 1570 to 1650 nm, said optical amplifier comprising:
- a plurality of erbium-doped fibers;
- and
- a plurality of optical filters, each of which is interposed between the individual erbium-doped fibers, said optical filters are configured so that a total of the transmission characteristics, which is a sum of the transmission characteristics of each of said optical filters, is obtained by inverting a wavelength gain characteristic of said erbium-doped fibers in the 1570 to 1650 nm band and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases.
An optical amplifier, comprising:
- a plurality of rare-earth element doped fibers;
- a plurality of optical filters each of which is interposed between the individual rare-earth doped fibers, each respective individual optical filter having a transmission characteristic that is identical to an inversion of a wavelength gain characteristic of the one of said rare-earth element doped fibers which precedes the respective optical filter;
- and
- said optical filters are configured so that a total of the transmission characteristics, which is a sum of the transmission characteristics of each of said optical filters, is obtained by inverting a wavelength gain characteristic of said rare-earth element doped fibers and shifting the inverted characteristic in a direction as to increase a transmission rate as a wavelength increases.
An optical amplifier, comprising:
- a plurality of rare-earth element doped fibers;
- and
- a plurality of optical filters, each of which is interposed between the individual rare-earth element doped fibers, said optical filters are configured so that a total of the transmission characteristics, which is a sum of the transmission characteristics of each of said optical filters, is obtained by inverting a wavelength gain characteristic of said rare-earth element doped fiber and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases.
An optical amplifier, comprising:
- optical fibers arranged in series;
- optical filters, each respective optical filter being positioned between two adjacent optical fibers in the series of optical fibers, wherein the optical filters are configured so that a sum of the transmission characteristics of each of the optical filters is obtained by inverting a wavelength gain characteristic of the optical fibers and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases.
An optical amplifier, comprising:
- optical fibers arranged in series;
- and
- optical filters, each respective optical filter being positioned between two adjacent optical fibers in the series of optical fibers, wherein the optical filters are configured so that a sum of the transmission characteristics of each of said optical filters is obtained by inverting a wavelength gain characteristic of the optical fibers and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases,
- wherein the transmission characteristics of each of said optical filters is set such that loss of a post-stage optical filter is smaller than loss of a pre-stage optical filter.
An optical amplifier, comprising:
- optical fibers arranged in series;
- and
- optical filters, each respective optical filter being positioned between two adjacent optical fibers in the series of optical fibers, wherein the optical filters are configured so that a sum of the transmission characteristics of each of said optical filters is obtained by inverting a wavelength gain characteristic of the optical fibers and shifting the inverted characteristic in a direction as to increase a transmittance rate as a wavelength increases,
- wherein the transmission characteristics of each of said optical filters is set such that loss of a post-stage optical filter is larger than loss of a pre-stage optical filter.
Dependencies are inferred from the claim text.