Patents by Inventor David A. Willems

David A. Willems 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: 5278529
    Abstract: A broadband microstrip filter structure employs a first transmission line which basically consists of a series of capacitor plates which extend between a dielectric layer from a first location to a second location and each of the series of plates are connected together with a top plate on the top surface of the dielectric and a bottom plate located a given distance beneath the dielectric layer. A second transmission line alternates between the top and bottom layers of the dielectric and consists of a second series of capacitive plates whereby each capacitor is connected to an adjacent capacitor with the top plate of the first connecting to the bottom plate of the second and the bottom plate of the first connecting to the top plate of the second and so on. This pattern is repeated so that the conductor path alternates from the top to the bottom plate. Various capacitors are selected to provide predetermined length resonators while various other capacitors are provided to provide coupling sections.
    Type: Grant
    Filed: February 13, 1992
    Date of Patent: January 11, 1994
    Assignee: ITT Corporation
    Inventor: David A. Willems
  • Patent number: 5262740
    Abstract: A transmission line structure operates as a transformer and includes at least two intertwined serpentine planar transmission lines positioned on a substrate with the lines repeatedly crossing each other with said areas of crossing including an airbridge or other structure which physically isolates one line from the other.
    Type: Grant
    Filed: April 9, 1992
    Date of Patent: November 16, 1993
    Assignee: ITT Corporation
    Inventor: David A. Willems
  • Patent number: 5180998
    Abstract: A reflection-type phase shifter employs an artificial delay line which is constructed of high impedance transmission line sections for the series inductive elements in the transmission line. Each junction between inductances in the transmission line is associated with a separate FET pair. The FET pair includes a first FET having the source to drain path coupled between the junction and a point of reference potential. The gate electrode of the first FET is coupled via the source to drain path of a second FET to the point of reference potential. The gate electrode of the second FET is coupled to one terminal of a resistor which is of a larger value compared to the ON resistance of the FET. This resistor has another terminal coupled to a control voltage source.
    Type: Grant
    Filed: November 5, 1991
    Date of Patent: January 19, 1993
    Assignee: ITT Corporation
    Inventor: David A. Willems
  • Patent number: 5172072
    Abstract: A high efficiency harmonic injection power amplifier has a power amplifier circuit, and at least a second-harmonic termination circuit which is coupled in parallel with the power amplifier circuit so to sample a small portion of the input signal and to inject into the power output signal an amplified harmonic signal which is phase-shifted for proper harmonic termination. The second-harmonic termination circuit includes a frequency multiplier for multiplying the frequency of the sampled input signal to twice the fundamental frequency, i.e., to 2f.sub.o, an amplifier for amplifying the 2f.sub.o signal to the level of the corresponding harmonic component of the power amplifier output signal, and a phase shifter for shifting the phase of the second-harmonic signal for proper harmonic termination. Additional harmonic termination circuits may be provided for terminating third- and higher-order harmonics.
    Type: Grant
    Filed: September 6, 1991
    Date of Patent: December 15, 1992
    Assignee: ITT Corporation
    Inventors: David A. Willems, Edward L. Griffin, Inder J. Bahl, Michael D. Pollman
  • Patent number: 5168242
    Abstract: An active-type broadband power divider has a pair of distributed amplifiers which are coupled together by a distributed capacitive coupling to provide a predetermined phase shift between respective output signals thereof. The distributed amplifiers are in the form of a row of three-terminal transistors having their gates and drains connected to gate and drain lines. The gate and drain lines are artificial transmission lines. By distributing the capacitive coupling between the gate and/or drain lines, a constant 90 degree phase shift is obtained over the entire bandwidth of the artificial transmission lines. For a 180 degree phase shift, a third distributed amplifier is provided with distributed capacitive coupling between its gate or drain line and that of the second distributed amplifier.
    Type: Grant
    Filed: November 20, 1991
    Date of Patent: December 1, 1992
    Assignee: ITT Corporation
    Inventors: David A. Willems, Victor E. Steel
  • Patent number: 4714904
    Abstract: A magnetostatic wave device unit in which the magnetic biasing unit includes a carrier member which contains one of the pole pieces and forms an enlarged mechanical and electrical support surface for a magnetostatic wave device.
    Type: Grant
    Filed: November 5, 1986
    Date of Patent: December 22, 1987
    Assignee: ITT Aerospace Optical
    Inventor: David A. Willems