Flexible WDM network architecture
US6192173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1999 |
| Grant date | Feb 20, 2001 |
| Priority date | — |
| Expiry date | Jun 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/02216
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A unidirectional or bidirectional node for use in an optical communications network, a network consisting of such nodes and a method of maintaining a target loss around a ring. The node comprises one or more optical couplers as well as either or both of drop circuitry connected to an output port and add circuitry connected to an input port. This allows for changes to the wavelength plan without interruption of the ring traffic. If add circuitry is used, the wavelengths in the filtered add signal should be distinct from those of the incoming signal on the main optical path which is merged with the add signal. When separate fibers are used for transmitting and receiving data between a hub and nodes in a ring, the through loss of the couplers is reduced for upstream couplers, which increases the available loss to be assigned to the fiber. The method of maintaining a target loss around a ring relies on the known through loss of the coupler at each node to set the gain of an amplifier connected to the node.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.