Patents by Inventor Chien-Fu Shih

Chien-Fu Shih 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: 7738933
    Abstract: An apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: June 15, 2010
    Assignee: Conductus, Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian H. Moeckly
  • Publication number: 20090079515
    Abstract: An apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Application
    Filed: January 8, 2008
    Publication date: March 26, 2009
    Applicant: Conductus Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian H. Moeckly
  • Patent number: 7317364
    Abstract: A method and apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Grant
    Filed: July 11, 2006
    Date of Patent: January 8, 2008
    Assignee: Conductus, Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian H. Moeckly
  • Publication number: 20060250196
    Abstract: A method and apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Application
    Filed: July 11, 2006
    Publication date: November 9, 2006
    Applicant: Conductus, Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian Moeckly
  • Patent number: 7117025
    Abstract: A method and apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: October 3, 2006
    Assignee: Conductus, Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian H. Moeckly
  • Publication number: 20030058061
    Abstract: A method and apparatus for providing dynamic and remote tuning of a cryo-cooled bandpass filter is disclosed. The device includes resonator element and a voltage sensitive element as part of the capacitance in a narrow band filter circuit. A varactor such as a GaAs varactor may be used. Alternatively, a capacitor having a voltage-sensitive dielectric such as SrTiO3 may be used. A computer may be connected to the varactor to provide for automated tuning. The voltage-sensitive capacitor may be integral with the resonator element. The invention provides for remote and dynamic tuning of a narrow bandpass filter while located within its sealed cryo-cooled environment.
    Type: Application
    Filed: June 3, 2002
    Publication date: March 27, 2003
    Applicant: Conductus, Inc.
    Inventors: Chien-Fu Shih, Yongming Zhang, Brian H. Moeckly
  • Patent number: 6529750
    Abstract: The present invention provides for a method and apparatus to control non-adjacent cross-coupling in a micro-strip filter. In instances of weak cross-coupling, such as a filter circuit on a high dielectric constant substrate material (e.g., LaAIO3 with dielectric constant of 24), a closed loop is used to inductively enhance the cross-coupling. The closed loop increases the transmission zero levels. For strong cross-coupling cases, such as a filter circuit on a lower dielectric constant substrate material (e.g., MgO with dielectric constant of 9.6), a capacitive cross-coupling cancellation mechanism is introduced to reduce the cross-coupling. In the latter instance, the transmission zero levels are moved down.
    Type: Grant
    Filed: April 2, 1999
    Date of Patent: March 4, 2003
    Assignee: Conductus, Inc.
    Inventors: Dawei Zhang, Ji-Fuh Liang, Chien-Fu Shih
  • Patent number: 6438394
    Abstract: The present invention provides for a super-narrow band filter using frequency dependent L-C components. The invention utilizes a frequency dependent L-C circuit with a positive slope k for the inductor values as a function of frequency. The positive k value allows the realization of a very narrow-band filter.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: August 20, 2002
    Assignee: Conductus, Inc.
    Inventors: Dawei Zhang, Guo-Chun Liang, Chien-Fu Shih