摘要:
In accordance with the invention, an optical communication system is provided with one or more automatic dispersion compensation modules. Each module has an adjustable dispersion element, a data integrity monitor and a feedback network whereby the monitor adjusts the dispersion element to optimize system performance. In a preferred embodiment the dispersion compensating modules comprise chirped fiber Bragg gratings in which the chirp is induced in the grating by passing a current along distributed thin film heaters deposited along the length of the fiber. The magnitude of the applied current determines the dispersion of the grating. A data integrity monitor is configured to sense the integrity of transmitted data and to provide electrical feedback for controlling the current applied to the grating.
摘要:
A high speed optical communication system (≧10 Gbit/s) is compensated for temperature variation by providing it with one or more automatic dispersion compensation modules. Each module has an adjustable dispersion element, a data integrity monitor and a feedback network whereby the monitor adjusts the dispersion element to compensate for temperature variation. In a preferred embodiment the dispersion compensating modules comprise chirped fiber Bragg gratings in which the chirp is induced in the grating by passing a current along distributed thin film heaters deposited along the length of the fiber. The magnitude of the applied current determines the dispersion of the grating. A data integrity monitor is configured to sense the integrity of transmitted data and to provide electrical feedback for controlling the current applied to the grating.
摘要:
In accordance with the invention, an optical waveguide grating with adjustable chirp comprises a waveguide grating in thermal contact with an electrically controllable heat-transducing body which varies the temperature along the length of the grating. The heat-transducing body can generate heat on the fiber or remove heat from the fiber to establish a temperature gradient along the grating. In an exemplary embodiment, the heat-transducing body is a resistive film coating whose local resistance varies along the length of the grating. Electrical current passed through the film generates a temperature gradient along the grating approximately proportional to the local resistance of the film, and the amount of chirp can be adjusted by the current. The resulting devices are simple, compact and power efficient.
摘要:
A tunable chromatic dispersion compensator for optical communication systems is disclosed. An optical grating, such as a fiber Bragg grating, non-chirped, linearly chirped or non-linearly chirped, is coated on its outer surface with a coating have a variable diameter and strained is applied to the fiber. The fiber may be latchably strained so that the grating characteristics may be changed or tuned while avoiding use of a continuous power supply. Various optical networking applications using such dispersion compensating devices are also disclosed.
摘要:
A method for making a chirped grating device capable of a broad bandwith for optical communication systems is disclosed. An intrinsically-chirped optical grating is externally strained to alter the range of chirping. The external strain may be induced by a gradient-generating body bonded onto the length of the fiber grating that may be latchably strained so that the grating characteristics may be changed or tuned while avoiding use of a continuous power supply. Various optical networking applications using such dispersion compensating devices are also disclosed.
摘要:
This invention is predicated upon applicants' discovery that the performance of thermally adjustable fiber grating devices is enhanced by disposing them within a vessel for thermal isolation. The vessel is sufficiently larger than the fiber to avoid contact with the grating yet sufficiently small to isolate the grating from substantial air currents. Conveniently, the vessel is a cylindrical tube having elastomeric end seals. Advantageously microcapillary tubes passing through the elastomeric seals provide openings for the fiber to pass through the tube.
摘要:
A tunable chromatic dispersion compensator for optical communication systems is disclosed. An optical grating, such as a fiber Bragg grating, nonchirped, linearly chirped or non-linearly chirped, is strained to alter the dispersion compensator characteristics, preferably with a gradient-generating body bonded onto the length of the fiber grating. The body may be latchably strained so that the grating characteristics may be changed or tuned while avoiding use of a continuous power supply. Various optical networking applications using such dispersion compensating devices are also disclosed.
摘要:
In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a first plurality of transponders each generating and/or receiving an information-bearing optical signal at a different channel wavelength from one another. An optical coupling arrangement, which may include one or more reconfigurable optical switches, transfers the channel wavelengths between a link connected to the node and the first plurality of transponders. The arrangement is adaptable to reconfigure its operational state to selectively direct different ones of the channel wavelengths from the link to different ones of the transponders without disturbing the optical path through the node traversed by any other channel wavelengths. A communications and configuration arrangement is provided, which transfers data identifying the respective channel wavelengths at which the transponders operate from the transponders to the optical coupling arrangement. In response to the transferred data, the communications and configuration arrangement reconfigures the operational state of the optical coupling arrangement.
摘要:
In a WDM optical communication system that includes a plurality of nodes interconnected by communication links, a node is provided that includes a first plurality of transponders each generating and/or receiving an information-bearing optical signal at a different channel wavelength from one another. An optical coupling arrangement, which may include one or more reconfigurable optical switches, transfers the channel wavelengths between a link connected to the node and the first plurality of transponders. The arrangement is adaptable to reconfigure its operational state to selectively direct different ones of the channel wavelengths from the link to different ones of the transponders without disturbing the optical path through the node traversed by any other channel wavelengths. A communications and configuration arrangement is provided, which transfers data identifying the respective channel wavelengths at which the transponders operate from the transponders to the optical coupling arrangement. In response to the transferred data, the communications and configuration arrangement reconfigures the operational state of the optical coupling arrangement.
摘要:
A programmable encoder is provided that includes at least one optical input for receiving a modulated broadband optical signal and at least one optical output. A dispersion element receives the optical signal from the optical input and spatially separates the optical signal into a plurality of wavelength components. A collimating element is provided for collimating the plurality of wavelength components. An actuatable optical arrangement receives the collimated plurality of wavelength components from the collimating element. The actuatable optical arrangement includes a digital micromirror device (DMD) from which a programmably selected subset of wavelength components are reflected at least twice before being directed to a selected one of optical outputs to thereby encode the CDMA signal.