Patents by Inventor David F. Williard

David F. Williard 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).

  • Battery saving method for portable communications receivers
    Patent number: 4804954
    Abstract: A system transmitting synchronization signals and coded message signals is described. In particular, coded synchronization signals are used to indicate the transmission of coded message signals or the absence of transmission of coded message signals following the transmission of the coded synchronization signal, thereby providing a battery saving function for a personal communications receiver.
    Type: Grant
    Filed: April 30, 1987
    Date of Patent: February 14, 1989
    Assignee: Motorola, Inc.
    Inventors: Philip P. Macnak, David F. Williard