Patents by Inventor Norman E. Cartwright

Norman E. Cartwright 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).

  • Attenuation of microwave signals
    Patent number: 4786915
    Abstract: It is sometimes necessary to reduce the power of microwave transmissions, e.g. to avoid overloading a receiver or to reduce a transmitter's potential to cause interference. The invention reduces the power by inserting radiation absorbent material into the aperture of the antenna. In the preferred embodiment a membrane of absorbent plastics is stretched across the aperture of the dish reflector.
    Type: Grant
    Filed: March 16, 1988
    Date of Patent: November 22, 1988
    Assignee: British Telecommunications public limited company
    Inventors: Norman E. Cartwright, Miles E. Butcher