Patent application number | Description | Published |
20100046948 | SYSTEM AND METHOD FOR RECEIVING HIGH SPECTRAL EFFICIENCY OPTICAL DPSK SIGNALS - Apparatus and methods are provided for receiving differential phase-shift keyed (DPSK) optical signals subjected to tight optical filtering, such as may be experienced by 40 Gb/s and 100 Gb/s channels in a dense wavelength division multiplexing (DWDM) communications system with 50 GHz channel spacing. An optical DPSK receiver is described which employs an optical delay interferometer (ODI) demodulator having a free spectral range (FSR) that is larger than the symbol rate (SR) of the DPSK signal to be demodulated. The receiver includes means for introducing an additional power imbalance between the outputs of the ODI demodulator, and the additional power imbalance may be related to the ratio of FSR to SR. The additional power imbalance increases the signal tolerance to tight optical filtering, thereby achieving high spectral efficiency in applications such as DWDM. | 02-25-2010 |
20120189303 | OPTICAL TRANSPORT MULTIPLEXING CLIENT TRAFFIC ONTO PARALLEL LINE SYSTEM PATHS - An optical line card system includes one or more input interfaces for receiving information, a line interface comprising a plurality of line transponders, and a multiplexer for multiplexing output of the one or more input interfaces onto the plurality of line transponders. The one or more input interfaces have an aggregate information rate R | 07-26-2012 |
20130070786 | Communication Through Phase-Conjugated Optical Variants - An optical transport system configured to transmit at least two phase-conjugated optical variants carrying the same modulated symbols, with the phase-conjugated optical variants in being different from one another in one or more of polarization of light, the time of transmission, spatial localization, optical carrier wavelength, and subcarrier frequency during transmission. The two phase-conjugated optical variants can be generated by a single polarization-diversity transmitter to be orthogonally polarized, and propagate through an optical transmission link with the same wavelength and spatial path. The optical variants are detected and processed at the receiver in a manner that enables coherent summation of the corresponding electrical signals prior to constellation de-mapping. The coherent summation tends to cancel out the deleterious effects of nonlinear distortions imparted on the individual phase-conjugated optical variants in an optical fiber transmission link because said nonlinear distortions tend to be opposite to each other. | 03-21-2013 |
20130071119 | COMMUNICATION THROUGH PRE-DISPERSION-COMPENSATED PHASE-CONJUGATED OPTICAL VARIANTS - An apparatus comprises an optical transmitter that comprises a processor and at least one optical modulator. The processor is configured to generate electronic representations of at least two pre-dispersion-compensated phase-conjugated optical variants carrying a same modulated payload data for transmission. The at least one optical modulator is configured to modulate the electronic representations, wherein an amount of dispersion induced on the pre-dispersion-compensated phase-conjugated optical variants depends on an accumulated dispersion (AD) of a transmission link through which the pre-dispersion-compensated phase-conjugated optical variants are to be transmitted. The amount of dispersion induced on the phase-conjugated optical variants may be approximately −AD/2, where AD is the accumulated dispersion of the transmission link. The pre-dispersion-compensated phase-conjugated optical variants are different from one another in one or more dimensions such as the polarization of light, the time of transmission, the spatial localization, the optical carrier wavelength, or the subcarrier frequency during transmission. | 03-21-2013 |
20130089339 | System, Method And Apparatus For High-Sensitivity Optical Detection - An apparatus receives data encoded in a format where information bits for transmission are mapped into symbols each carrying a plurality of bits, some of which are encoded through a frequency-shift keyed (FSK) format and the rest of which are encoded through an additional modulation format on at least one FSK carrier. The receiver detects the signal through a dual-polarization coherent receiver front-end, and recovers polarization components of the signal by decoding a first non-zero portion of a plurality of bits carried by a symbol based on frequency slot position of at least one FSK carrier in the polarization components and a second non-zero portion of the plurality of bits carried by the symbol based on the additional modulation carried by at least one FSK carrier in the polarization components. Pilot-assisted orthogonal frequency-division de-multiplexing (PA-OFDM) may be used for spectrally-efficient signal reception, even in the presence of severe FSK errors. | 04-11-2013 |
Patent application number | Description | Published |
20090132101 | SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM FOR ENERGY EXTRACTING VESSEL NAVIGATION - A Supervisory Control And Data Acquisition (SCADA) system guides navigation of a vessel enabled to extract energy from wind and/or water currents primarily in offshore marine environments. An exemplary SCADA system could embody server and client software applications running on microprocessor systems at a remote control central service logging and energy distribution facility, and the vessel itself. The remote control service facility runs Human Machine Interface (HMI) software in the form of a Graphical User Interface (GUI) allowing choices to maximize system performance. The central server accesses information to control vessel position based on transmitted Global Position Satellite (GPS) data from the vessel, and weather information from the Geographic Information System (GIS) provided by multiple spatial temporal data sources. A server-side optimization algorithm fed the parameters delivered from vessel aerodynamic/hydrodynamic performance simulation software models, the vessel onboard sensor data, and integrated real-time weather and environmental data determines an optimal navigation through weather systems and presents choices to the HMI. | 05-21-2009 |
20100198429 | SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM FOR ENERGY EXTRACTING VESSEL NAVIGATION - A Supervisory Control And Data Acquisition (SCADA) system guides navigation of a vessel enabled to extract energy from wind and/or water currents primarily in offshore marine environments. An exemplary SCADA system could embody server and client software applications running on microprocessor systems at a remote control central service logging and energy distribution facility, and the vessel itself. The remote control service facility runs Human Machine Interface (HMI) software in the form of a Graphical User Interface (GUI) allowing choices to maximize system performance. The central server accesses information to control vessel position based on transmitted Global Position Satellite (GPS) data from the vessel, and weather information from the Geographic Information System (GIS) provided by multiple spatial temporal data sources. A server-side optimization algorithm fed the parameters delivered from vessel aerodynamic/hydrodynamic performance simulation software models, the vessel onboard sensor data, and integrated real-time weather and environmental data determines an optimal navigation through weather systems and presents choices to the HMI. | 08-05-2010 |
20100271097 | Pulse Width Modulation Sequence Maintaining Maximally Flat Voltage During Current Transients - A digital circuit implementing pulse width modulation controls power delivered in what one can model as a second order or higher order system. An exemplary control plant could embody a step-down switch mode power supply providing a precise sequence of voltages or currents to any of a variety of loads such as the core voltage of a semiconductor unique compared to its input/output ring voltage. One of several algorithms produce a specific predetermined sequence of pulses of varying width such that the voltage maintains maximally flat characteristics while the current delivered to the load from the system plant varies within a range bounded only by inductive element continuous conduction at the low power extreme and non-saturation of the inductor core at the high power extreme. The specific pulse width modulation sequence controls a plant such that the voltage maintains maximally flat characteristics in one embodiment without a feed-forward or feedback loop physically embodied in the control system thereby reducing the parts cost or control semiconductor production yield cost while enhancing noise immunity and long term reliability of the control system. Several specific algorithms maintain maximally flat voltage despite extreme load variations therewith control plant element parameters otherwise exacerbating excessive voltage fluctuation during the given current transients. | 10-28-2010 |
20110148374 | CONTROL MULTIPLEXOR FOR A SWITCH MODE POWER SUPPLY - A digital circuit directs operation of a pulse width modulation or pulse frequency modulation controller varying its control between closed loop and open loop topology. An exemplary control plant could embody a step-down switch mode power supply providing a precise sequence of voltages or currents to any of a variety of loads such as the core voltage of a semiconductor unique compared to its input/output ring voltage. A state machine monitors pulse width or pulse frequency from the pulse width modulation or pulse frequency modulation controller, respectively, while either type of controller operates in its closed loop topology, to determine if the present power state of the system matches the predicted load as characterized from a predetermined model used in conjunction with design automation tools. The state machine averages pulse widths or pulse frequencies monitored in the closed loop topology. If the average deviates from the predicted pulse width or pulse frequency for the present power state, the state machine updates a corresponding value in a table of pulse width or pulse frequency values from which an open loop controller applying pulse width modulation or pulse frequency modulation, respectively, generates a near critical damped step response during system power state transitions or maintains a maximally flat voltage during system current transients. | 06-23-2011 |
20110172852 | SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM FOR ENERGY EXTRACTING VESSEL NAVIGATION - A Supervisory Control And Data Acquisition (SCADA) system guides navigation of a vessel enabled to extract energy from wind and/or water currents primarily in offshore marine environments. An exemplary SCADA system could embody server and client software applications running on microprocessor systems at a remote control central service logging and energy distribution facility, and the vessel itself. The remote control service facility runs Human Machine Interface (HMI) software in the form of a Graphical User Interface (GUI) allowing choices to maximize system performance. The central server accesses information to control vessel position based on transmitted Global Position Satellite (GPS) data from the vessel, and weather information from the Geographic Information System (GIS) provided by multiple spatial temporal data sources. A server-side optimization algorithm fed the parameters delivered from vessel aerodynamic/hydrodynamic performance simulation software models, the vessel onboard sensor data, and integrated real-time weather and environmental data determines an optimal navigation through weather systems and presents choices to the HMI. | 07-14-2011 |
20120325290 | SOLAR COGENERATION VESSEL - An offshore vessel embodies a mobile buoyant energy recovery system enabled to extract energy from solar power. An exemplary energy recovery system comprises concentrating solar thermal power systems (CSP) or concentrating photovoltaic power (CPV) systems on the deck of the vessel. Within the vessel hull, ballast water serves multiple purposes. The ballast not only stabilizes the vessel, but also provides reactant for hydrogen electrolysis or ammonia synthesis, or steam for a turbine. For CPV systems the ballast conducts heat as a coolant improving the efficiency and durability of photovoltaic cells. For CSP systems the ballast water becomes superheated steam through a primary heat exchanger in the concentrator. In some embodiments, some steam from the CSP primary heat exchanger or from the CPV coolant system undergoes high-pressure electrolysis of enhanced efficiency due to its high temperature. In some embodiments, the remaining steam that did not undergo electrolysis drives a steam turbine providing electrical current for electrolysis. A secondary heat exchanger takes heat from the steam expelled from an energy storage process to efficiently distill ballast water at a lower temperature thus minimizing corrosion and build-up of scale. A remote control Supervisory Control and Data Acquisition System (SCADA) determines position, navigation, configuration, and operation of the preferably unmanned modular mobile buoyant energy recovery structure based on Geospatial Information Systems (GIS), Velocity Performance Prediction (VPP) models, Global Positioning Satellites (GPS) and various onboard sensors and controls. | 12-27-2012 |
20130060402 | SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM FOR ENERGY EXTRACTING VESSEL NAVIGATION - A Supervisory Control And Data Acquisition (SCADA) system guides navigation of a vessel enabled to extract energy from wind and/or water currents primarily in offshore marine environments. An exemplary SCADA system embodies server and client software applications running on microprocessor systems at a remote control central service logging and energy distribution facility, and the vessel itself. | 03-07-2013 |
20130239861 | TURBINE-INTEGRATED HYDROFOIL - A turbine integrated within a hydrofoil extracts energy from a free-flowing motive fluid. In the preferred embodiment, the turbine is of the crossflow variety with runner blades coaxial to the width of the hydrofoil. The foremost edge of the hydrofoil comprises a slot covered by a continuously adjustable gate for controlling the overall drag imposed by the turbine. The hydrofoil mounts to a sailing vessel by means of a gimbal on a structure affixed to the hull, enabling the turbine to optimally respond to changes in direction of the free-flowing motive fluid and facilitating guidance and stability of the vessel. | 09-19-2013 |