Patents by Inventor Eric C. Fisher

Eric C. Fisher 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).

  • Publication number: 20230142413
    Abstract: A receiver for detecting at least one electromagnetic signal while the receiver is moving relative to the Earth's magnetic field, the receiver comprising: an SQUID array for generating an output that is a transfer function of SQUID array magnetic flux that is supplied from a combination of an oscillating magnetic field of the at least one electromagnetic signal, the Earth's magnetic field, and a bias magnetic field; a bias-tee configured to divide the SQUID array output into a DC signal and an RF signal; a memory store configured to store a plurality of voltage and flux bias values, wherein each voltage value has a corresponding flux bias value that results in maximum SQUID array sensitivity; and a logic circuit configured to find a voltage value in the memory store that most closely matches the DC signal, and to apply to the SQUID array a flux bias corresponding to the most closely matched voltage value.
    Type: Application
    Filed: August 30, 2021
    Publication date: May 11, 2023
    Inventors: Eric C. Fisher, Marcio C. de Andrade, Brian A. Higa, Michael O'Brien
  • Patent number: 11630166
    Abstract: A receiver for detecting at least one electromagnetic signal while the receiver is moving relative to the Earth's magnetic field, the receiver comprising: an SQUID array for generating an output that is a transfer function of SQUID array magnetic flux that is supplied from a combination of an oscillating magnetic field of the at least one electromagnetic signal, the Earth's magnetic field, and a bias magnetic field; a bias-tee configured to divide the SQUID array output into a DC signal and an RF signal; a memory store configured to store a plurality of voltage and flux bias values, wherein each voltage value has a corresponding flux bias value that results in maximum SQUID array sensitivity; and a logic circuit configured to find a voltage value in the memory store that most closely matches the DC signal, and to apply to the SQUID array a flux bias corresponding to the most closely matched voltage value.
    Type: Grant
    Filed: August 30, 2021
    Date of Patent: April 18, 2023
    Assignee: United States of America as represented by the Secretary of the Navy
    Inventors: Eric C. Fisher, Marcio C. de Andrade, Brian A. Higa, Michael O'Brien
  • Patent number: 10802086
    Abstract: A circuit includes a Superconducting Quantum Interference Array (SQIF), a bias circuit, and a coil. The SQIF generates an output voltage that is a transfer function of the magnetic flux perpendicularly passing through the SQIF. An external magnetic field and a bias magnetic field supply the magnetic flux. The bias circuit generates a bias current for biasing the SQIF at an operating point. The coil generates the bias magnetic field through the SQIF from the bias current of the bias circuit. The bias magnetic field provides nullifying feedback to the SQIF that counterbalances a low-frequency portion of the external magnetic field, such that the output voltage of the SQIF detects a high-frequency portion of the external magnetic field. The circuit can be a receiver with the output voltage of the SQIF detecting an electromagnetic signal while the receiver is moving with changing orientation relative to the Earth's magnetic field.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: October 13, 2020
    Assignee: United States of America as Represented by the Secretary of the Navy
    Inventors: Eric C. Fisher, Marcio C. de Andrade, Michael O'Brien
  • Publication number: 20200284855
    Abstract: A circuit includes a Superconducting Quantum Interference Array (SQIF), a bias circuit, and a coil. The SQIF generates an output voltage that is a transfer function of the magnetic flux perpendicularly passing through the SQIF. An external magnetic field and a bias magnetic field supply the magnetic flux. The bias circuit generates a bias current for biasing the SQIF at an operating point. The coil generates the bias magnetic field through the SQIF from the bias current of the bias circuit. The bias magnetic field provides nullifying feedback to the SQIF that counterbalances a low-frequency portion of the external magnetic field, such that the output voltage of the SQIF detects a high-frequency portion of the external magnetic field. The circuit can be a receiver with the output voltage of the SQIF detecting an electromagnetic signal while the receiver is moving with changing orientation relative to the Earth's magnetic field.
    Type: Application
    Filed: March 5, 2020
    Publication date: September 10, 2020
    Inventors: Eric C. Fisher, Marcio C. de Andrade, Michael O'Brien