Lightwave communication systems using semiconductor optical amplifiers
US6473212B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1999 |
| Grant date | Oct 29, 2002 |
| Priority date | — |
| Expiry date | Feb 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/2914
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Substantially error-free communications is achieved in an optical communication system that includes optical amplifiers by detecting bits transmitted in the amplified optical signal using a detection threshold that is derived as a function of a maximum power level associated with a first bit value, e.g., bit “0”, and a minimum power level associated with a second bit value, e.g., bit “1”. Importantly, this detection scheme can be used to accurately detect bit patterns in the amplified signal even in the presence of nonlinear distortions caused by gain variations, such as inter-modal distortion and saturation induced crosstalk. In a wavelength division multiplexed (WDM) system comprising semiconductor optical amplifiers, for example, the detection threshold can be set at a level corresponding to PTOTAL/2N, where PTOTAL represents the total power in the WDM signal and N represents the number of optical channels in the WDM signal. According to another aspect of the invention, the effect of gain fluctuations becomes smaller as the number of channels increase. In particular, a smoothing effect is realized for the total effective saturation power as gain variation…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.