Patents by Inventor Peter James Doherty

Peter James Doherty 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).

  • Antenna impedance matching network requiring no switch contacts
    Patent number: 5874921
    Abstract: An apparatus for providing an antenna impedance matching network that does not include mechanical switch contacts is disclosed. A retractable antenna includes a conductive plate moveable between the extended and retracted positions of the antenna. When the conductive plate is located in the extended position an impedance matching circuit responsive to the position of the conductive plate is connected between the antenna and an amplifier of a radio telephone. In response to location of the conductive plate in the retracted position, the impedance matching circuit is shorted out such that the antenna is connected directly to the amplifier via a capacitive effect between the conductive plate and a conductive coil of the shorted out impedance matching circuit.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: February 23, 1999
    Assignee: Ericsson, Inc.
    Inventors: Peter James Doherty, Darrell Epperson