The present invention relates to fiber-optic communications networks, and more particularly, to optical network equipment such as optical amplifiers that have control and data paths.
Fiber-optic networks are used to support voice and data communications. In optical networks that use wavelength division multiplexing, multiple wavelengths of light are used to support multiple communications channels on a single fiber.
Optical amplifiers are used in fiber-optic networks to amplify optical signals. For example, optical amplifiers may be used to amplify optical data signals that have been subject to attenuation over fiber-optic paths. A typical amplifier may include erbium-doped fiber coils that are pumped with diode lasers. Raman amplifiers have also been investigated. Discrete Raman amplifiers may use coils of dispersion-compensating fiber to provide Raman gain. Distributed Raman amplifiers provide gain in the transmission fiber spans that are used to carry optical data signals between network nodes.
It is an object of the present invention to provide optical network equipment such as optical amplifiers that have control and data paths.
It is also an object of the present invention to provide optical network equipment such as optical amplifiers that have control buses and data buses for interfacing with components in the equipment.
These and other objects of the invention are accomplished in accordance with the present invention by providing optical amplifiers and other optical network equipment for use in fiber-optic communications links in fiber-optic networks. The fiber-optic links may be used to carry optical data signals associated with wavelength-division-multiplexing channels.
The equipment may include various optical components such as optical gain stages for providing optical gain for the optical signals, variable optical attenuators, dynamic spectral-filters, add/drop multiplexer components, optical channel monitors, dispersion-compensating elements, temperature controllers and sensors, photodetectors, and optical switches. A control unit may be used to control the operation of the equipment. The control unit may be based on processors, programmable logic devices, and other circuitry.
Circuit boards and other structures may be used to support the control unit circuitry and the components. Communications paths between the control unit circuitry and the components may be used to support communications between the control unit and the components. The communications paths may be paths that support serial communications or parallel communications. Synchronous and asynchronous communications may be supported. Multidrop buses and point-to-point paths may be used. Multiple components may share a bus using time-division-multiplexing arrangements. The use of these different communications arrangements may facilitate the process by which optical network equipment may be modified and expanded by adding components or modules.
Further features of the invention and its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments.