In-fiber two-stage amplifier providing WDM signal conditioning
US5978131A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1998 |
| Grant date | Nov 2, 1999 |
| Priority date | — |
| Expiry date | Apr 7, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0209
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The amplifier is a two-stage amplifier in which dispersion compensation and WDM channel equalization are carried out using a plurality of in-waveguide Bragg gratings placed between the two stages. The first stage has a gain able to raise the intensity of WDM optical communications signals to a high enough level that after dispersion compensation and equalization, the signals fed into the second stage nearly or substantially saturate the second stage amplifier. The noise figure signal-to-noise ratio is thereby of good quality since there are no significant losses at the signal input of the signal into the optical amplifier. Erbium-doped optically pumped fiber amplifiers are used for the two stages. An add/drop filter can be appended to the end of the conditioning Bragg gratings. Residual optical signal from the fiber Bragg grating may be used to optically pump another amplifier for amplifying longer wavelength optical signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.