Method and apparatus for combining add/drop optical signal lines from a plurality of branching units
US5719697A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 10, 1996 |
| Grant date | Feb 17, 1998 |
| Priority date | — |
| Expiry date | Oct 10, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S2301/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An optical signal processing method and apparatus for providing a noise feedback loop that uses existing noise within the optical system to saturate a chain of amplifiers after the branching unit, thereby preventing information channels in a WDM signal containing empty channels from becoming overamplified as they pass through downstream amplifiers. The method and apparatus uses an existing drop amplifier which emits ASE noise as a side effect. A coupler connects the ASE noise to a filter. The filtered ASE noise is fed into an existing trunk amplifier by a second coupler. The trunk amplifier increases gain to the filtered ASE noise to a level high enough to saturate the amplifier chain, without requiring an external noise generating device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.