WDM optical network and switching node with pilot tone communications
US6556321B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 1999 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Aug 12, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0298
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A communications network has a plurality of nodes interconnected by an optical transmission medium. The transmission medium is capable of a carrying a plurality of wavelengths organized into bands. A filter at each node for drops a band associated therewith and passively forwards other bands through the transmission medium. A device is provided at each node for adding a band to the transmission medium. Communication can be established directly between a pair of nodes in the network sharing a common band without the active intervention of any intervening node. This allows the network to be protocol independent. Also, the low losses incurred by the passive filters permit relatively long path lengths without optical amplification.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.