Gain flattening with nonlinear Sagnac amplifiers
US6377391B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Mar 29, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S2301/06
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus and a method provide gain flattening in communications systems wherein a large number of optical signals at different wavelengths must be amplified while maintaining signal power within an acceptable range. Because of differences in gain of typical optical amplifiers as a function of wavelength and input power, the signals at different wavelengths are not amplified by the same amounts. Thus, when amplified multiple times, certain signals tend to become severely attenuated to the point of being no longer useable. The present gain flattening apparatus and method cause signals having higher gain-power products to be attenuated by a greater amount in response to Kerr-induced phase shifting such that after multiple stages of amplification, all the signal powers converge toward a small range of acceptable output powers. The apparatus provides amplification, multiple times, of a series of signals with a plurality of wavelengths covering a very wide spectral range, while maintaining the power of all the signals within a small range. The spread of this signal power range is robust against changes in the signal power, against changes in the number of signals, and, to some degree…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.