Patents by Inventor Robert Strother-Stewart

Robert Strother-Stewart 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).

  • CEMENT PLUG DETECTION SYSTEM AND METHOD
    Publication number: 20170122096
    Abstract: In accordance with one aspect of the disclosure a method includes positioning a cement plug in a casing string, completing a casing cementing process, launching the cement plug down the casing string, and detecting a magnetic field of an electro-magnetic transmitter coupled to the cement plug or a magnet disposed on an outer surface of the casing string with a magnetic sensor disposed on the outer surface of the casing string.
    Type: Application
    Filed: November 2, 2016
    Publication date: May 4, 2017
    Inventors: Willem George Durtler, Robert Strother-Stewart, Dimitar Dimitrov, Hendrik Leroux, Brian Dewald
  • Method and apparatus for locating and tracking a QPSK carrier
    Patent number: 5699385
    Abstract: In a receiver for receiving a carrier modulated with data, there is provided a system for locating and tracking said carrier. The carrier is located by sweeping a frequency range containing said carrier. False lockup are inherent when a wide frequency sweep demodulator attempts to lock onto a carrier, and the system recognizes such lockups by monitoring data from a Viterbi error correction circuit. On false lockup, the system breaks the lockup and continues the sweep until the true data carrier is located and tracked.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: December 16, 1997
    Assignee: Scientific-Atlanta, Inc.
    Inventors: Mark J. D'Sylva, Steven Lawrence, Robert Strother-Stewart