Abstract: The present disclosure provides systems and methods for noise tolerant signal processing in a pilot assisted data receiver, including: given received pilots with common pilot components and individual pilot components, computing coefficients associated with the individual pilot components of the received pilots; and applying the computed coefficients to the received pilots to obtain conditioned pilots. The individual pilot components result from relatively slow changes of the received pilots relative to the common pilot components. The common pilot components result from relatively fast changes of the received pilots relative to the individual pilot components.

Abstract: The present invention provides a transmission system, including: a transmitter including a transmitter filter; a receiver including a receiver filter; and a communicative coupling between the transmitter and the receiver; wherein the transmitter filter and the receiver filter are matched for noise reduction, and wherein the combined responses of the transmitter filter and the receiver filter satisfy the Nyquist criteria. Optionally, the transmitter filter includes a pulse shaping quasi digital finite impulse response filter. Optionally, the receiver filter includes an inductor-capacitor ladder based filter.

Abstract: A directionless optical architecture is described for reconfigurable optical add/drop multiplexers (ROADMs) and wavelength selective switches (WSSs). The directionless architecture utilizes a directionless wavelength switch coupled between client devices and ROADMs/WSSs to eliminate the need to hard-wire client devices to a wavelength division multiplexed (WDM) network. Accordingly, client device connections can be automatically routed without manual intervention to provide a highly resilient network design which can recover route diversity during failure scenarios. Additionally, the present invention minimizes deployments of costly optical transceivers while providing superior resiliency. Further, the present invention couples the directionless optical architecture and associated optical protection mechanisms with existing mesh restoration schemes to provide additional resiliency.

Abstract: A Field Programmable Gate Array (FPGA) to implement channel equalization to mitigate group velocity dispersion in an optical system. In one embodiment, a mapping is loaded into the FPGA whereby the in-phase and quadrature components of the baseband sequence to be filtered are routed to accumulators to form various sums, where each sum is multiplied by a corresponding distinct filter tap coefficient value according to the mapping to form various products, and where the products are summed to provide the in-phase and quadrature components of the filtered output.

Abstract: A Field Programmable Gate Array (FPGA) to implement channel equalization to mitigate group velocity dispersion in an optical system. In one embodiment, a mapping is loaded into the FPGA whereby the in-phase and quadrature components of the baseband sequence to be filtered are routed to accumulators to form various sums, where each sum is multiplied by a corresponding distinct filter tap coefficient value according to the mapping to form various products, and where the products are summed to provide the in-phase and quadrature components of the filtered output.

Abstract: The present disclosure provides systems and methods for noise tolerant signal processing in a pilot assisted data receiver, including: given received pilots with common pilot components and individual pilot components, computing coefficients associated with the individual pilot components of the received pilots; and applying the computed coefficients to the received pilots to obtain conditioned pilots. The individual pilot components result from relatively slow changes of the received pilots relative to the common pilot components. The common pilot components result from relatively fast changes of the received pilots relative to the individual pilot components.

Abstract: The present disclosure provides systems and methods for the compensation of signal distortion in fiber optic communication systems and the like. More specifically, the present disclosure provides an orthogonal polarization detection and broadband pilot (OPDBP) technique for the compensation of nonlinear cross polarization (i.e. nonlinear cross polarization modulation) (XPolM) induced noise and nonlinear nonlinear cross phase modulation (XPM) induced noise in a high data rate polarization multiplexed (PM) multilevel-quadrature amplitude modulated (M-QAM) channel due to neighboring channels. This approach allows for the compensation of both XPolM and XPM simultaneously, providing several dBs of optical reach extension. The approach uses a pilot tone based orthogonal polarization detection scheme with broadband (i.e. a few GHz wide) filtering of the pilot tones.

Abstract: The present invention provides a directionless optical architecture for reconfigurable optical add/drop multiplexers (ROADMs) and wavelength selective switches (WSSs). The directionless architecture utilizes a directionless wavelength switch coupled between client devices and ROADMs/WSSs to eliminate the need to hard-wire client devices to a wavelength division multiplexed (WDM) network. Accordingly, client device connections can be automatically routed without manual intervention to provide a highly resilient network design which can recover route diversity during failure scenarios. Additionally, the present invention minimizes deployments of costly optical transceivers while providing superior resiliency. Further, the present invention couples the directionless optical architecture and associated optical protection mechanisms with existing mesh restoration schemes to provide additional resiliency.

Abstract: The present disclosure provides electrical domain suppression of linear crosstalk in optical communication systems using single-carrier implementations. This electrical domain suppression applies spectral shaping in the electronic radio frequency (RF) domain. Advantageously, spectral shaping in the electronic RF domain transfers system complexity from the bulk optical domain into the highly integrated CMOS (or equivalent) domain. The spectral shaping can include electronic circuitry including an electrical filtering block and a signal linearization block prior to optical modulation. The electrical filtering block suppresses coherent interference terms and can include an RF-domain low pass filter. The signal linearization block linearizes modulator response to compensate spectral regrowth due to nonlinear mixing in the modulator.

Abstract: The present invention provides a high-speed 100G optical transceiver for InfiniBand and Ethernet with associated mapping to frame InfiniBand and Ethernet into GFP-T. The optical transceiver utilizes an architecture which relies on standards-compliant (i.e., multi-sourced) physical client interfaces. These client interfaces are back-ended with flexible, programmable Field Programmable Gate Array (FPGA) modules to accomplish either InfiniBand or Ethernet protocol control, processing, re-framing, and the like. Next, signals are encoded with Forward Error Correction (FEC) and can include additional Optical Transport Unit (OTU) compliant framing structures. The resulting data is processed appropriately for the subsequent optical re-transmission, such as, for example, with differential encoding, Gray encoding, I/Q Quadrature encoding, and the like. The data is sent to an optical transmitter block and modulated onto an optical carrier. Also, the same process proceeds in reverse on the receive side.

Abstract: The present disclosure relates to fiber optic networks carrying sensitive information such as classified government communications, sensitive financial information, proprietary corporate information, and associated systems and methods for secure transmission where fiber tampering is easily detected. The present invention provides improved security systems and methods for fiber optic communication links. Specifically, a hollow-core photonic bandgap fiber is deployed as a transmission medium. A secure fiber optic communication link is established over the hollow-core photonic bandgap fiber with a monitoring mechanism. The monitoring mechanism is configured to detect large losses and large spectral variability each indicative of loss introduced by malicious intrusion attempts. Further, the monitoring mechanism allows easy differentiation of intrusion relative to normal system variations thereby reducing false positives and missed intrusions.

Abstract: The present invention provides an optical networking device for re-amplifying, re-shaping, and re-timing an optical signal, as well as providing distortion compensation and performance monitoring of the optical signal. The optical networking device includes an all-optical regenerator device for one or more of re-amplifying, re-shaping, and re-timing the optical signal; a distortion compensator device for compensating for distortion associated with the optical signal; and a quality-of-signal monitoring device for measuring the quality of the optical signal. Preferably, the all-optical regenerator device, the distortion compensator device, and the quality-of-signal monitoring device are disposed within a single module. The quality-of-signal monitoring device measures the optical signal subsequent to distortion compensation. Alternatively, the quality-of-signal monitoring device measures the optical signal subsequent to distortion compensation and all-optical regeneration.

Abstract: In general, the present invention provides novel approaches to signal propagation modeling that utilize the following: 1) geographic segmentation is applied by separating a large fiber optic network into individual non-overlapping segments, defined by optical add/drop placements; 2) impairment segmentation is applied, such that optical noise, self-phase, cross-phase, four-wave mixing, and other impairments are all treated separately; 3) each impairment is calculated by the most efficient approach to achieve the minimum required accuracy, the approaches being fully numeric, semi-analytic, or empirical; 4) impairment concatenation rules are applied to compute an overall impairment experienced by a signal that traverses more than one segment; and 5) impairment scaling rules are applied to rapidly estimate changes in configuration that can lead to improved performance (i.e. higher capacity, longer distance, or lower cost).

Abstract: The present disclosure provides a polarization multiplexed transceiver, including: a transmitter; a receiver; circuitry within the transmitter configured to insert pilot tones as a reference state of polarization for a polarization multiplexed signal; and circuitry within the receiver configured to de-multiplex the polarization multiplexed signal using the pilot tones. The transmitted signal is constructed in such a manner as to facilitate the division of the receiver processing between the analog and digital domains such that the implementation may be simultaneously both highly spectrally efficient and power efficient.

Abstract: The present disclosure provides systems and methods for noise tolerant signal processing in a pilot assisted data receiver, including: given received pilots with common pilot components and individual pilot components, computing coefficients associated with the individual pilot components of the received pilots; and applying the computed coefficients to the received pilots to obtain conditioned pilots. The individual pilot components result from relatively slow changes of the received pilots relative to the common pilot components. The common pilot components result from relatively fast changes of the received pilots relative to the individual pilot components.

Abstract: The present disclosure provides systems and methods for the compensation of signal distortion in fiber optic communication systems and the like. More specifically, the present disclosure provides an orthogonal polarization detection and broadband pilot (OPDBP) technique for the compensation of nonlinear cross polarization (i.e. nonlinear cross polarization modulation) (XPolM) induced noise and nonlinear nonlinear cross phase modulation (XPM) induced noise in a high data rate polarization multiplexed (PM) multilevel-quadrature amplitude modulated (M-QAM) channel due to neighboring channels. This approach allows for the compensation of both XPolM and XPM simultaneously, providing several dBs of optical reach extension. The approach uses a pilot tone based orthogonal polarization detection scheme with broadband (i.e. a few GHz wide) filtering of the pilot tones.

Abstract: The present invention provides a directionless reconfigurable optical add/drop multiplexer (ROADM) system. The present invention provides a scalable all-optical switching element that includes a combination of 1×N wavelength selective switches (WSS), 1×N splitters/combiners, optical amplifiers, and tunable filters to provide a fully non-blocking solution which can be deployed in a scalable manner. The 1×N splitters are configured to split multiples copies of a plurality of drop wavelengths which can be amplified and sent to a tunable filter which selects out a particular wavelength for drop. The 1×N combiners are configured to combine multiple add wavelengths for egress transmission.

Abstract: The present invention provides a serializer/deserializer (SERDES) circuit that can cover both client- and network-side interfaces for high-speed data rates. The present invention leverages commonality between the client and network (also known as line) side, and accommodates differences in a flexible manner. In one exemplary embodiment, the present invention provides a four-channel implementation to meet the requirement of both interfaces. The SERDES circuit can be capable of supporting both 40 Gb/s and 56 Gb/s data rates, can include an integrated DQPSK pre-coder and I/Q input/output signals, and can support RZ clock recovery. Additionally, the SERDES circuit can include differential coding support, electronic pre-emphasis, receiver-side electronic dispersion compensation, and the like.

Abstract: The present disclosure provides a multi-carrier optical transmitter, receiver, transceiver, and associated methods utilizing offset quadrature amplitude modulation thereby achieving significant increases in spectral efficiency, with negligible sensitivity penalties. In an exemplary embodiment, an optical transmitter includes circuitry configured to generate a plurality of optical subcarriers, a plurality of data signals for each of the plurality of subcarriers, and a plurality of modulator circuits for each of the plurality of subcarriers, wherein each of the plurality of modulator circuits includes circuitry configured to offset an in-phase component from a quadrature component of one of the plurality data signals by one-half baud period.

Abstract: An optical switch fabric, including: a first set of horizontal optical waveguides receiving a plurality of wavelengths; a plurality of wavelength-selective drop optical switches associated with the first set of horizontal optical waveguides, wherein the plurality of wavelength-selective drop optical switches are each configured to drop a selected wavelength from a horizontal optical waveguide of the first set of horizontal optical waveguides to an associated vertical optical waveguide of a plurality of vertical optical waveguides; and a plurality of controllable optical switches associated with the plurality of vertical optical waveguides, wherein the plurality of controllable optical switches are each configured to direct a selected wavelength from a vertical optical waveguide of the plurality of vertical optical waveguides to a horizontal optical waveguide of a second set of horizontal optical waveguides, and wherein the second set of horizontal optical waveguides output a plurality of wavelengths.