Patents by Inventor John Christopher H. Davis

John Christopher H. Davis 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).

  • Telephone summing circuit
    Patent number: 4230908
    Abstract: The addition of two digitized audio signals, each of which has been non-linearly compressed and PCM encoded, is accomplished by converting only one of the signal samples (preferably the smaller) to an exponential-format value which may be linearly added to the other.
    Type: Grant
    Filed: January 22, 1979
    Date of Patent: October 28, 1980
    Assignee: Plessey Canada Limited
    Inventors: John Christopher H. Davis, Richard A. Hatherill