Patents by Inventor David B. Ruthledge

David B. Ruthledge 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: 8049563
    Abstract: The present invention discloses a distributed power amplifier topology and device that efficiently and economically enhances the power output of an RF signal to be amplified. The power amplifier comprises a plurality of push-pull amplifiers interconnected in a novel circular geometry that preferably function as a first winding of an active transformer having signal inputs of adjacent amplification devices driven with an input signal of equal magnitude and opposite phase. The topology also discloses the use of a secondary winding that matches the geometry of primary winding and variations thereof that serve to efficiently combine the power of the individual power amplifiers. The novel architecture enables the design of low-cost, fully-integrated, high-power amplifiers in the RF, microwave, and millimeter-wave frequencies.
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: November 1, 2011
    Assignee: California Institute of Technology
    Inventors: Ichiro Aoki, Seyed-Ali Hajimiri, David B. Ruthledge, Scott D. Kee
  • Patent number: 7425869
    Abstract: The present invention discloses a distributed power amplifier topology and device that efficiently and economically enhances the power output of an RF signal to be amplified. The power amplifier comprises a plurality of push-pull amplifiers interconnected in a novel circular geometry that preferably function as a first winding of an active transformer having signal inputs of adjacent amplification devices driven with an input signal of equal magnitude and opposite phase. The topology also discloses the use of a secondary winding that matches the geometry of primary winding and variations thereof that serve to efficiently combine the power of the individual power amplifiers. The novel architecture enables the design of low-cost, fully-integrated, high-power amplifiers in the RF, microwave, and millimeter-wave frequencies.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: September 16, 2008
    Assignee: California Institute of Technology
    Inventors: Ichiro Aoki, Seyed-Ali Hajimiri, David B. Ruthledge, Scott David Kee