Patents by Inventor Andrew F. Schaefer

Andrew F. Schaefer 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: 10581527
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Grant
    Filed: November 27, 2017
    Date of Patent: March 3, 2020
    Assignee: LOCKHEED MARTIN CORPORATION
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Publication number: 20180083708
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Application
    Filed: November 27, 2017
    Publication date: March 22, 2018
    Inventors: Andrew F. SCHAEFER, Paul T. COYNE, John C. CECCHERELLI
  • Patent number: 9831955
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Grant
    Filed: June 8, 2017
    Date of Patent: November 28, 2017
    Assignee: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Publication number: 20170279536
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Application
    Filed: June 8, 2017
    Publication date: September 28, 2017
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Patent number: 9755754
    Abstract: A system and method for adaptive equalization in a communication system. The system can include a modulator, a processor coupled to the modulator, and a memory coupled to the processor. The memory can store software instructions that, when executed by the processor, cause the processor to perform operations that can include generating, for each of one or more scan frequencies of interest, an optimal bias setting of the modulator. Data indicating a selection of a range of frequencies to be processed by the communication system can be received at the processor. The operations can include determining, responsive to the receiving, the optimal bias setting corresponding to the selected range of frequencies. A bias of the modulator can be adjusted based on the determined optimal bias setting, the adjusting providing adaptive equalization of the flatness response of the communication system.
    Type: Grant
    Filed: February 24, 2015
    Date of Patent: September 5, 2017
    Assignee: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, John C Ceccherelli, Paul T. Coyne, Daniel S. Parsons, Stephen V. Robertson
  • Patent number: 9705280
    Abstract: A system, method, and device for efficiently maintaining a stable operational temperature for precise operation of a laser. The system can include an ambient temperature sensor, a cooler controller adapted to control a cooler having an adjustable setpoint, a processor, and a memory coupled to the processor. The memory can store software instructions that, when executed by the processor, cause the processor to perform operations that can include receiving data from the sensor and determining the ambient temperature based on the received data. The determined ambient temperature can be compared to a current setpoint. When the delta exceeds a predetermined threshold, the setpoint can be adjusted to enable the operating environment of the laser to reach a control temperature closer to ambient conditions (and within a predetermined operating temperature range of the laser). Adjusted setpoint data can be transmitted to the cooler controller to adjust the setpoint of the cooler.
    Type: Grant
    Filed: February 24, 2015
    Date of Patent: July 11, 2017
    Assignee: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, John C Ceccherelli, Paul T. Coyne, Stephen V. Robertson
  • Patent number: 9698911
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: July 4, 2017
    Assignee: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Patent number: 9658477
    Abstract: A system, method, and device for RF upconversion is provided. The system can include a laser, a local oscillator, and an RF mixer, an EAM, a photonic filter, and a photodiode. The mixer can receive an LO signal from the local oscillator. The mixer can be configured to mix LO with an IF signal and output a mixed signal. The EAM can receive an optical signal from the laser, receive the mixed signal from the mixer, and be configured to convert the mixed signal into the photonic domain by modulating the optical signal based on the mixed signal to output a modulated optical signal. The photonic filter can receive the modulated optical signal and can be configured to output a filtered optical signal. The photodiode can receive the filtered optical signal and can be configured to convert the filtered optical signal into the RF domain to output upconverted RF output.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: May 23, 2017
    Assignee: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Publication number: 20170005732
    Abstract: A system, method, and device for RF upconversion. The system can include a laser, two EAMs, a photonic filter, a photonic service filter, two photodiodes, and a mixer. The first EAM can convert a received RF signal into the photonic domain by modulating an optical signal (received from the laser) based on the received RF signal to output a modulated optical signal. The photonic filter can output a filtered optical signal based on the modulated optical signal to the first photodiode which can output a filtered RF signal in the RF domain. The second EAM can output an LO modulated optical signal based on a received LO to the service filter which can output a filtered LO optical signal to the second photodiode which can output a filtered LO signal in the RF domain. The mixer can mix the filtered RF and LO signals to generate an IF signal.
    Type: Application
    Filed: June 30, 2015
    Publication date: January 5, 2017
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Publication number: 20170003524
    Abstract: A system, method, and device for RF upconversion is provided. The system can include a laser, a local oscillator, and an RF mixer, an EAM, a photonic filter, and a photodiode. The mixer can receive an LO signal from the local oscillator. The mixer can be configured to mix LO with an IF signal and output a mixed signal. The EAM can receive an optical signal from the laser, receive the mixed signal from the mixer, and be configured to convert the mixed signal into the photonic domain by modulating the optical signal based on the mixed signal to output a modulated optical signal. The photonic filter can receive the modulated optical signal and can be configured to output a filtered optical signal. The photodiode can receive the filtered optical signal and can be configured to convert the filtered optical signal into the RF domain to output upconverted RF output.
    Type: Application
    Filed: June 30, 2015
    Publication date: January 5, 2017
    Applicant: Lockheed Martin Corporation
    Inventors: Andrew F. Schaefer, Paul T. Coyne, John C. Ceccherelli
  • Publication number: 20160248609
    Abstract: A system and method for adaptive equalization in a communication system. The system can include a modulator, a processor coupled to the modulator, and a memory coupled to the processor. The memory can store software instructions that, when executed by the processor, cause the processor to perform operations that can include generating, for each of one or more scan frequencies of interest, an optimal bias setting of the modulator. Data indicating a selection of a range of frequencies to be processed by the communication system can be received at the processor. The operations can include determining, responsive to the receiving, the optimal bias setting corresponding to the selected range of frequencies. A bias of the modulator can be adjusted based on the determined optimal bias setting, the adjusting providing adaptive equalization of the flatness response of the communication system.
    Type: Application
    Filed: February 24, 2015
    Publication date: August 25, 2016
    Inventors: Andrew F. Schaefer, John C. Ceccherelli, Paul T. Coyne, Daniel S. Parsons, Stephen V. Robertson
  • Publication number: 20160245557
    Abstract: A system, method, and device for efficiently maintaining a stable operational temperature for precise operation of a laser. The system can include an ambient temperature sensor, a cooler controller adapted to control a cooler having an adjustable setpoint, a processor, and a memory coupled to the processor. The memory can store software instructions that, when executed by the processor, cause the processor to perform operations that can include receiving data from the sensor and determining the ambient temperature based on the received data. The determined ambient temperature can be compared to a current setpoint. When the delta exceeds a predetermined threshold, the setpoint can be adjusted to enable the operating environment of the laser to reach a control temperature closer to ambient conditions (and within a predetermined operating temperature range of the laser). Adjusted setpoint data can be transmitted to the cooler controller to adjust the setpoint of the cooler.
    Type: Application
    Filed: February 24, 2015
    Publication date: August 25, 2016
    Inventors: Andrew F. Schaefer, John C. Ceccherelli, Paul T. Coyne, Stephen V. Robertson
  • Publication number: 20140046510
    Abstract: Methods and devices for calculating an estimate of a wind vector. A maneuver of a platform may be identified as a steady-straight motion maneuver, a partial turn maneuver, or a full turn maneuver. A preliminary estimate of a wind vector corresponding to a wind condition prevailing near the platform may be calculated by applying a maneuver-specific calculating method. A gain associated with the preliminary estimate of the wind vector may be calculated by applying a state-specific calculation method. A filtered estimate of the wind vector may be updated based, at least in part, on the preliminary estimate of the wind vector and the gain associated with the to preliminary estimate of the wind vector.
    Type: Application
    Filed: August 13, 2012
    Publication date: February 13, 2014
    Applicant: Lockheed Martin Corporation
    Inventors: Michael S. Randolph, Joseph J. Saunders, Andrew F. Schaefer