Signal identification in optical communications networks
US7551858B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 2006 |
| Grant date | Jun 23, 2009 |
| Priority date | — |
| Expiry date | Sep 17, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0298
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Signals in an optical communications network, such as optical channels in an optical WDM network for example, are each identified by at least two low frequency dither tones with which the signal is modulated. The dither tones alternate with a predetermined periodicity to produce a cyclically repeated sequence of dither tones. A network parameter, such as a channel identifier for example, is obtained by the detection of the particular combination of dither tones in the sequence. To detect a number of network parameters a signal is modulated with a number of cyclically repeated sequences of dither tones each uniquely identifying a respective network parameter. In some implementations each dither tone in a cyclically repeated sequence of dither tones is repeated with substantially the same phase and coherent averaging is performed over a number of periods to detect dither tones on low power signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.