Patents by Inventor Douglas G. Forster

Douglas G. Forster 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).

  • Geographical location system and method for locating radiotelephone engaged in a call
    Patent number: 6026305
    Abstract: A cellular radiotelephone (24) engages in a call over a bidirectional channel (32) involving a cellsite base station (68) within a cellular network (22). Upon receipt of a notice (46), a geographical location computer (20) is activated and transmits a call locate instruction identifying the bidirectional channel (32) to a plurality of dual channel receivers (56, 58, 60, and 61). The dual channel receivers (56, 58, 60, and 61) are then tuned to the bidirectional channel (32) and receive the forward (78) and reverse (82) location signals over forward and reverse directions of the bidirectional channel (32). A probable location of the cellular radiotelephone (24) is determined by measuring phase differences of the forward (78) and reverse (82) location signals at each of the dual channel receivers (56, 58, 60, and 61).
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: February 15, 2000
    Assignee: GTE Government Systems Corporation
    Inventors: Sheldon N. Salinger, Douglas G. Forster