Abstract:
Systems and techniques to optically boost a router. In general, in one implementation, the technique includes: receiving an optical signal defining a packet of data, initiating electronic routing of the optical packet, and initiating optical routing of the optical packet. The optical routing involves determining forwarding information based on a routing field in the optical packet, and if optical forwarding is available, terminating the electronic routing of the packet before completion of the electronic routing, and forwarding the optical signal, which defines the packet, based on the determined forwarding information.
Abstract:
Techniques, devices, and systems for generating tunable dispersions to control or compensate for dispersions in optical signals by using wave-guiding grating elements with nonlinear group delays.
Abstract:
Techniques for monitoring polarization-mode dispersion in a fiber span and location such fiber span in a fiber system based on the stimulated Brillouin scattering process.
Abstract:
A nonlinearly chirped fiber grating for achieving tunable dispersion compensation, dispersion slope compensation, polarization mode dispersion, chirp reduction in directly modulated diode lasers, and optical pulse manipulation. A dynamical dispersion compensation mechanism can be implemented in a fiber communication system based on such a nonlinearly chirped fiber grating.
Abstract:
Methods and systems used to perform sweep-free stimulated Brillouin scattering-based fiber optical sensing are described. In one aspect, a method includes interrogating different parts of a Brillouin gain spectrum using multiple optical tones in an optical fiber. The interrogating includes sending at least two pump tones into the optical fiber from one end of the optical fiber, such that a frequency spacing between the pump tones is larger than a width of the Brillouin gain spectrum. The interrogating also includes sending at least two probe tones into the optical fiber from another end of the optical fiber, such that a frequency spacing between the probe tones is different from the frequency spacing between the pump tones. The method further includes generating a sensing output based on the interrogating.
Abstract:
Methods and systems for implementing polarization division multiplexing to allow recovery of data in different multiplexed channels at a receiving end without recovering multiplexed polarizations used in the transmitting stage.
Abstract:
Techniques for compensating for PMD in multiple WDM channels by processing all WDM channels in the same manner without demultpliexing the channels. A feedback control is provided to decrease the worst-case power penalty and the channel fading probability by optimizing over the entire group of WDM channels.
Abstract:
Techniques and devices based on a wave-guiding element which has a spatial grating pattern that is an oscillatory variation along its optic axis. The wave-guiding element is configured to receive an input optical signal and to produce an output optical signal by reflection within a Bragg reflection band produced by the spatial grating pattern so as to produce time delays of different reflected spectral components as a nonlinear function of spatial positions along said optic axis at which the different reflected spectral components are respectively reflected. Such a wave-guiding element may be a nonlinearly chirped fiber grating A control unit may be engaged to the wave-guiding element and is operable to change a property of the spatial grating pattern along the optic axis to tune at least relative time delays of the different reflected spectral components nonlinearly with respect to wavelength.
Abstract:
An adaptive optics compensation approach for an OAM multiplexed FSO communication system is described, in which a Gaussian beam is used to probe the turbulence-induced wavefront distortions and derive the correction pattern for compensating the OAM beams. Using this approach, we demonstrate simultaneous compensation of multiple OAM beams each carrying a 100-Gbit/s data channel through emulated atmospheric turbulence. The results indicate that the turbulence-induced crosstalk and power penalty could be efficiently mitigated by ˜12.5 dB and ˜11 dB respectively.
Abstract:
In at least one aspect, a device for Orbital Angular Momentum (OAM) based optical communication includes a first spatial light modulator configured to down-convert a first plurality of higher-order OAM modes from a communication signal to a second plurality of higher-order OAM modes and a first Gaussian mode, a second spatial light modulator configured to drop the first Gaussian mode and add a second Gaussian mode to the second plurality of higher-order OAM modes, and a third spatial light modulator configured to up-convert the second plurality of higher-order OAM modes and the second Gaussian mode to a third plurality of higher-order OAM modes for further communications.