Patents Assigned to Hemisphere GPS Inc.
  • Patent number: 7429952
    Abstract: A multilayer antenna structure configured to receive Global Navigation Satellite System (GNSS) and augmentation signals. The antenna includes a microstrip patch radiation element disposed at a top layer and a ground plane forming a first interior layer, the ground plane including at least two coupling apertures, and the ground plane isolated from said radiation element by a low loss dielectric. The antenna structure also includes a bottom layer, the bottom layer is isolated from the ground plane by another dielectric; at least two feed lines operably connected to a hybrid coupler disposed on the bottom layer; and an active circuit on the bottom layer, a first port of said active circuit operably connected to the hybrid coupler.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: September 30, 2008
    Assignee: Hemisphere GPS Inc.
    Inventor: Jia Sun
  • Patent number: 7400956
    Abstract: A sensor system for vehicle steering control comprising: a plurality of global navigation satellite sensor systems (GNSS) including receivers and antennas at a fixed spacing to determine a vehicle position, velocity and at least one of a heading angle, a pitch angle and a roll angle based on carrier phase corrected real time kinematic (RTK) position differences. The roll angle facilitates correction of the lateral motion induced position errors resultant from motion of the antennae as the vehicle moves based on an offset to ground and the roll angle. The system also includes a control system configured to receive the vehicle position, heading, and at least one of roll and pitch, and configured to generate a steering command to a vehicle steering system.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: July 15, 2008
    Assignee: Hemisphere GPS Inc.
    Inventors: Walter Feller, Michael L. Whitehead, John A. McClure
  • Patent number: 7400294
    Abstract: A method and system for local computation of information to improve accuracy in a differential Global Navigation Satellite Systems (GNSS). The method comprising: determining a current location of a reference receiver; comparing the current location with at least one stored location; if a resultant of the comparing is less than a selected threshold, identifying as a reference location the at least one stored location, which is closest to the current location; otherwise establishing the current location as the reference location and storing the current location. The method also includes computing the information from signals from one or more GNSS satellites the based on the reference location; and transmitting the information for reception by one or more remote receivers.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: July 15, 2008
    Assignee: Hemisphere GPS Inc.
    Inventors: Michael L. Whitehead, John McClure
  • Patent number: 7388539
    Abstract: A method and system for reducing Global Navigation Satellite System (GNSS) carrier tracking loop ambiguities comprising: receiving a plurality of GNSS satellite signals with a first antenna in operable communication with a first tracking device and a second antenna in communication with a second tracking device in at least one GNSS receiver; and sharing of data between the first tracking device and the second tracking device. The sharing is configured to facilitate a commonality in a carrier phase derived in the first and second tracking devices. The sharing also results in a cancellation of the commonality when a difference phase is formed between a carrier phase from the first tracking device and a carrier phase from the second tracking device.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: June 17, 2008
    Assignee: Hemisphere GPS Inc.
    Inventors: Michael L. Whitehead, Cary Davis