Patents by Inventor David C. Sjolund

David C. Sjolund 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: 5721554
    Abstract: A near field planar wavefront generation method that uses a relatively small number (three to five) of transmitting antennas disposed a predetermined distance from an antenna array having a multi-wavelength aperture that is part of a system under test. The method creates a synthesized one-dimensional linear planar wavefront of radiation over at least ten wavelengths for testing the antenna array of the system under test. The planar wavefront is formed at a specific frequency and at predetermined distance from the transmitting antennas, typically in the range of from 100 to 200 feet. The transmitting antennas synthesize a plane wave with linear phase progression to simulate tilt variations. To achieve this, electromagnetic energy signals emitted by the respective transmitting antennas are amplitude and phase weighted to synthesize the one dimensional linear plane wave to produce a combined wavefront having a linear phase front across the aperture of the antenna array of the system under test.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: February 24, 1998
    Assignee: Hughes Electronics
    Inventors: Stanley R. Hall, Donald E. Bostrom, David C. Sjolund