Systems and methods for determining minimal spectrum occupancy in routing and wavelength/spectrum assignment (RWA/RSA) in an optical network include performing, for a new demand request, a set of binary operations using a binary representation for each wavelength or portion of spectrum over all links in the optical network; and selecting, based on the set of binary operations, i) a route and ii) one of a) a wavelength and b) one or more portions of spectrum for the new demand request.

There is provided a distance-adaptive and fragmentation-aware all-optical traffic grooming (DFG) method, which addresses the all-optical traffic grooming problem while considering the transmission reach constraints. The DFG procedure provisions traffic demands in optical channels such that the spectrum requires for guard bands is minimized. The DFG procedure provisions optical channels such that network fragmentation is minimized while ensuring the transmission reach constrains over flexible-grid WDM networks.

Photonic devices, photonic integrated circuits, optical elements, and techniques of making and using the same are described. A photonic device includes an input region adapted to receive an optical signal including a multiplexed channel characterized by a distinct wavelength, a dispersive region optically coupled with the input region to receive the optical signal, the dispersive region including a plurality of sub-regions defined by an inhomogeneous arrangement of a first material and a second material, and a plurality of output regions optically coupled with the input region via the dispersive region. The plurality of sub-regions can include an input channel section, an in-coupler section, a parallel channel section, an out-coupler section, and an output channel section. The plurality of sub-regions together can configure the photonic device to demultiplex the optical signal and to isolate the multiplexed channel at a first output region of the plurality of output regions.

In an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid, it is difficult to improve the usage efficiency of an optical frequency band owing to the occurrence of fragmentation of the optical frequency band; therefore, an optical network controller according to an exemplary aspect of the present invention includes an optical frequency region setting means for setting a plurality of optical frequency regions in an optical frequency band used in an optical network based on a dense wavelength division multiplexing system using a flexible frequency grid; an optical path setting means for setting optical paths having a common attribute in at least one of the plurality of optical frequency regions; and an optical frequency region control means for changing an optical frequency width of the optical frequency region, and instructing the optical frequency region setting means to reconfigure, as the plurality of optical frequency regions, a plurality of optical frequency reconfigured regions each of which having the optical frequency width after having been changed.

Novel tools and techniques are provided for implementing optical frequency spectral optimization in dense wavelength division multiplexing (DWDM) flex grid systems. In various embodiments, based on a determination that one or more gaps of optical spectrum exist in a range of optical spectrum that contains one or more media channels that support transmission of corresponding one or more first signals, a computing system may determine a network wavelength service frequency assignment for shifting frequency of at least one media channel among the one or more media channels to optimize one or more spacings among the one or more media channels in the range of optical spectrum for supporting transmission of one or more second signals; and may cause one or more optical signal devices to shift a center frequency of each of the at least one media channel, based on the determined network wavelength service frequency assignment.

Novel tools and techniques are provided for implementing optical frequency spectral optimization in dense wavelength division multiplexing (DWDM) flex grid systems. In various embodiments, based on a determination that one or more gaps of optical spectrum exist in a range of optical spectrum that contains one or more media channels that support transmission of corresponding one or more first signals, a computing system may determine a network wavelength service frequency assignment for shifting frequency of at least one media channel among the one or more media channels to optimize one or more spacings among the one or more media channels in the range of optical spectrum for supporting transmission of one or more second signals; and may cause one or more optical signal devices to shift a center frequency of each of the at least one media channel, based on the determined network wavelength service frequency assignment.

The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it. In some embodiments, the receiver stage employs polarization-diversity techniques to enable it to operate on unpolarized/randomly polarized input signals.