Patents by Inventor Patricia W. McLain

Patricia W. McLain 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).

  • Position and velocity estimation system for adaptive weighting of GPS and dead-reckoning information
    Patent number: 5416712
    Abstract: An embodiment of the present invention is a combined GPS and dead-reckoning (DR) navigation sensor for a vehicle in which a pair of modifications are made to an otherwise conventional Kalman filter. Process noise is adapted to cope with scale factor errors associated with odometer and turning rate sensors, and correlated measurement error processing is added. When only two Doppler measurements (PRRs), or three with an awkward three-satellite geometry, are available, DR error growth can nevertheless be controlled. The measurement error correlations in the conventional Kalman filter covariance propagation and update equations are explicitly accounted for. Errors induced by selective availability periods are minimized by these two modifications.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: May 16, 1995
    Assignee: Trimble Navigation Limited
    Inventors: George J. Geier, Ardalan Heshmati, Kelly G. Johnson, Patricia W. McLain