Patents by Inventor Andrew W. Butler

Andrew W. Butler 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).

  • Controllable microwave attenuator
    Patent number: 4249144
    Abstract: A microwave attenuator consists of a plurality of variable attenuation PIN diodes connected in a serial path. At least one of the diodes forms part of a feed-back loop so that the attenuation level it provides can be adjusted to correspond with a reference signal. The effective level of the reference signal is modified in accordance with correction factors, by means of which non-linearities in the performance of the remaining diodes can be compensated.
    Type: Grant
    Filed: December 4, 1979
    Date of Patent: February 3, 1981
    Assignee: Marconi Instruments Limited
    Inventors: Geoffrey J. Hurst, Andrew W. Butler