Patents by Inventor George A. Sefler

George A. Sefler has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9413372
    Abstract: A multi-mode optic can receive as input a radio-frequency (RF) signal imposed on an optical carrier, and can output a speckle pattern. A digital representation of the radio-frequency signal can be obtained based on the speckle pattern. An optical sensor can be irradiated with a first portion of the speckle pattern, the first portion of the speckle pattern including an optical intensity profile that is different than an optical intensity profile of a second, spatially separated, portion of the speckle pattern. The multi-mode optic can impose the optical intensity profile on the first portion of the speckle pattern as a function of wavelength of the optical carrier. The optical intensity profiles of portions of the speckle pattern can define a mixing matrix. The digital representation of the RF signal can be obtained based on an output of the optical sensor and the mixing matrix.
    Type: Grant
    Filed: July 30, 2015
    Date of Patent: August 9, 2016
    Assignee: The Aerospace Corporation
    Inventors: George C. Valley, George A. Sefler
  • Patent number: 8902096
    Abstract: Systems and methods for converting wideband signals into the digital domain are provided herein. The system may include an electronic or guided-wave optic based replicator configured to obtain at least M replicas of a signal applied thereto, and an electronic or guided-wave optic based segmenter configured to segment a signal applied thereto into at least N segments based on time or wavelength. Together, the replicator and the segmenter obtain M×N segment replicas of the received signal. An electronic or guided-wave optic based mixer is configured to multiply the M×N segment replicas by a mixing matrix having dimension M×N and then to form M integrations each of N segment replicas so as to obtain a measurement vector of length M. A signal recovery processor is configured to obtain a digital representation of the received signal based on the measurement vector and the mixing matrix.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: December 2, 2014
    Assignee: The Aerospace Corporation
    Inventors: George C. Valley, George Sefler, Thomas Justin Shaw
  • Publication number: 20140266826
    Abstract: Systems and methods for converting wideband signals into the digital domain are provided herein. The system may include an electronic or guided-wave optic based replicator configured to obtain at least M replicas of a signal applied thereto, and an electronic or guided-wave optic based segmenter configured to segment a signal applied thereto into at least N segments based on time or wavelength. Together, the replicator and the segmenter obtain M×N segment replicas of the received signal. An electronic or guided-wave optic based mixer is configured to multiply the M×N segment replicas by a mixing matrix having dimension M×N and then to form M integrations each of N segment replicas so as to obtain a measurement vector of length M. A signal recovery processor is configured to obtain a digital representation of the received signal based on the measurement vector and the mixing matrix.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: The Aerospace Corporation
    Inventors: George C. VALLEY, George SEFLER, Thomas Justin SHAW
  • Patent number: 8750720
    Abstract: Various embodiments are directed to a photonic impulse generator comprising a periodically chirped photonic source a single-frequency photonic source, a photodetector, an optical coupler, and a filter. The optical coupler may be positioned to couple an output of the single-frequency photonic source to an output of the periodically chirped photonic source, resulting in a combined photonic signal. The photodetector may be positioned to receive the combined photonic signal and generate a combined electrical signal. The filter may be in electrical communication with an output of the photodetector to receive the combined electrical signal.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: June 10, 2014
    Assignee: The Aerospace Corporation
    Inventor: George A. Sefler
  • Publication number: 20120224859
    Abstract: Various embodiments are directed to a photonic impulse generator comprising a periodically chirped photonic source a single-frequency photonic source, a photodetector, an optical coupler, and a filter. The optical coupler may be positioned to couple an output of the single-frequency photonic source to an output of the periodically chirped photonic source, resulting in a combined photonic signal. The photodetector may be positioned to receive the combined photonic signal and generate a combined electrical signal. The filter may be in electrical communication with an output of the photodetector to receive the combined electrical signal.
    Type: Application
    Filed: March 1, 2011
    Publication date: September 6, 2012
    Applicant: The Aerospace Corporation
    Inventor: George A. Sefler
  • Patent number: 8026837
    Abstract: Systems and methods for converting wideband signals in the optical domain are provided. A device for obtaining a digital representation of a received signal may include a spatially dispersive element that may be configured to spatially disperse frequencies in an optical-domain representation of the received signal; a spatial light modulator that may be configured to mix the dispersed optical frequencies by imposing a mixing matrix on an optical intensity of the dispersed optical frequencies; an optical sensor that may be configured to obtain an electrical representation of the mixed dispersed optical frequencies; and a signal recovery processor that may be configured to obtain a digital representation of the received signal based on the electrical representation and the mixing matrix. The signal recovery processor may be further configured to determine a modulation format of the digital representation and may demodulate the digital representation based on the modulation format.
    Type: Grant
    Filed: April 22, 2010
    Date of Patent: September 27, 2011
    Assignee: The Aerospace Corporation
    Inventors: George C. Valley, George A. Sefler
  • Patent number: 6657723
    Abstract: A planar spectrograph for demultiplexing optical wavelength signals includes a monolithic substrate. The substrate has a diffraction grating etched therein. The diffraction grating is integrally formed in the substrate to be in operative relationship with input light to diffract and reflect the input light to a detector. A recess is formed in the substrate to accommodate a separate slab waveguide. A slab waveguide is dimensioned and configured to fit within the recess, and the waveguide guides input light to and from the diffraction grating. A silicon-on-insulator spectrographs is also described, as well as, fabrication processes for manufacturing these spectrographs.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: December 2, 2003
    Assignee: International Business Machines Corporation
    Inventors: Mitchell S. Cohen, George A. Sefler, James L. Speidell
  • Publication number: 20030197862
    Abstract: A planar spectrograph for demultiplexing optical wavelength signals includes a monolithic substrate. The substrate has a diffraction grating etched therein. The diffraction grating is integrally formed in the subtstrate to be in operative relationship with input light to diffract and reflect the input light to a detector. A recess is formed in the substrate to accommodate a separate slab waveguide. A slab waveguide is dimensioned and configured to fit within the recess, and the waveguide guides input light to and from the diffraction grating. A silicon-on insulator spectrographs is also described, as well as, fabrication processes for manufacturing these spectrographs.
    Type: Application
    Filed: December 13, 2000
    Publication date: October 23, 2003
    Inventors: Mitchell S. Cohen, George A. Sefler, James L. Speidell