Abstract: A steering controller can control steering of a vehicle and is suitable for precision farm controlling. The steering controller can rotate the steering shaft of the vehicle direct the vehicle on a desired path, for example, using a satellite positioning system. Components of the steering controller are environmental protected by a housing that has an opening extending between its front and rear surfaces. The opening is lined by a shaft. A hub located near the front of the opening can be coupled to the steering shaft of the vehicle. A motor has a stator fixed to the housing and a rotor fixed to the hub. When the housing is attached to a fixed location on the vehicle, the motor can rotate the steering shaft by rotating the hub with respect to the housing. A control module drives the motor based on commands from a guidance module.

Abstract: A system and method for collecting soil samples is provided that permits a user to develop or generate one or more paths in an agricultural field to collect soil samples with each soil core collection point along the path being identified. The agricultural field can be divided into management zones having similar productivity and each management zone can have a path with the identified collection points to collect samples for that management zone.

Abstract: A global navigation satellite sensor system (GNSS) control system and method for irrigation and related applications is provided for a boom assembly with main and extension boom sections, which are hingedly connected and adapted for folding. The control system includes an antenna and a receiver connected to the antenna. A rover antenna is mounted on the boom extension section and is connected to the receiver. A processor receives GNSS positioning signals from the receiver and computes locations for the antennas, for which a vector indicating an attitude of the extension boom section can be computed. Various boom arrangements and field configurations are accommodated by alternative aspects of the control system.

Abstract: A dual-frequency DSP correlator receives I and Q signal components from a down convertor in a GNSS receiver system. The signal components are cross-wiped (de-spread) for noise cancellation and can be combined for use in a processor.

Abstract: A multi-frequency GNSS antenna is provided which can be manufactured from PCB materials and exhibits good multipath rejection. The antenna is capable of receiving RHCP signals from all visible GNSS satellites across a wide beamwidth. A multi-frequency GNSS antenna manufacturing method includes the steps of providing PCB base and support assemblies, first and second feed networks and connecting said first and second feed networks to first and second hybrid connector outputs.

Abstract: An optical tracking vehicle control system includes a controller adapted for computing vehicle guidance signals and a guidance subsystem adapted for receiving the guidance signals from the controller and for guiding the vehicle. An optical movement sensor is mounted on the vehicle in optical contact with a travel surface being traversed by the vehicle. The optical movement sensor is connected to the controller and provides vehicle movement signals thereto for use by the controller in computing vehicle position. The optical movement sensor can be either mounted on a gimbal for movement independent of the vehicle, or, alternatively, multiple optical movement sensors can be provided for detecting yaw movements. GNSS and inertial vehicle position tracking subsystems are also provided. Still further, a method of tracking a vehicle with an optical movement sensor is provided.

Abstract: A method for locating GNSS-defined points, distances, directional attitudes and closed geometric shapes includes the steps of providing a base with a base GNSS antenna and providing a rover with a rover GNSS antenna and receiver. The receiver is connected to the rover GNSS antenna and is connected to the base GNSS antenna by an RF cable. The receiver thereby simultaneously processes signals received at the antennas. The method includes determining a vector directional arrow from the differential positions of the antennas and calculating a distance between the antennas, which can be sequentially chained together for determining a cumulative distance in a “digital tape measure” mode of operation. A localized RTK surveying method uses the rover antenna for determining relative or absolute point locations. A system includes a base with an antenna, a rover with an antenna and a receiver, with the receiver being connected to the antennas.

Abstract: A global navigation satellite sensor system (GNSS) and gyroscope control system for vehicle steering control comprising a GNSS receiver 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 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. The system includes gyroscopes for determining system attitude change with respect to multiple axes for integrating with GNSS-derived positioning information to determine vehicle position, velocity, rate-of-turn, attitude and other operating characteristics.

Abstract: A multi-frequency down converter includes first and second signal paths. A common local oscillator/synthesizer drives both of the signal paths. Exemplary applications include GNSS systems operating across superbands. The down converter is adapted for use in a GNSS receiver system.

Abstract: A machine control system and method includes an on-board GPS receiver, an on-board processor adapted to store a preplanned guide pattern and a guidance device. The processor includes a comparison function for comparing the vehicle GPS position with a line segment of the preplanned guide pattern. The processor controls the guidance device for guiding the vehicle along the line segment. Various guide pattern modification functions are programmed into the processor, including best-fit polynomial correction, spline correction, turn-flattening to accommodate minimum vehicle turning radii and automatic end-of-swath keyhole turning.

Abstract: A method for steering an agricultural vehicle comprising: receiving global positioning system (GPS) data including position and velocity information corresponding to at least one of a position, velocity, and course of the vehicle; receiving a yaw rate signal; and computing a compensated heading, the compensated heading comprising a blend of the yaw rate signal with heading information based on the GPS data. For each desired swath comprising a plurality of desired positions and desired headings, the method also comprises: computing an actual track and a cross track error from the desired swath based on the compensated heading and the position; calculating a desired radius of curvature to arrive at the desired track with a desired heading; and generating a steering command based on the desired radius of curvature to a steering mechanism, the steering mechanism configured to direct the vehicle.

Abstract: An antenna alignment and monitoring system is provided for telecom antennas and includes a pair of global navigation satellite system (GNSS) antennas mounted on a printed circuit board (PCB) for installation in a telecom antenna enclosure. Multiple telecom antennas are configured in an antenna array for mounting on a transmission tower or other elevated structure. A common GNSS receiver cycles among the GNSS antenna pairs for initially aligning and subsequently monitoring the azimuth alignment of the telecom antennas relative to a reference azimuth using GNSS triangulation.

Abstract: In the invention, a rover receiver first utilizes data from a base Receiver, a DGNSS reference network, or other differential source to compute a differentially corrected location. Then, using this location and data observed only at the rover, the rover computes an internal set of differential corrections that are stored in computer memory, updated as necessary, and applied in future times to correct observations taken by the rover. The possibly mobile rover receiver, therefore, corrects its own observations with differential corrections computed from its own past observations; relying on external differential for the sole purpose of establishing a reference location, and this is unlike prior art.

Abstract: A multi-antenna GNSS system and method provide earth-referenced GNSS heading and position solutions. The system and method compensate for partial blocking of the antennas by using a known attitude or orientation of the structure, which can be determined by an orientation device or with GNSS measurements. Multiple receiver units can optionally be provided and can share a common clock signal for processing multiple GNSS signals in unison. The system can optionally be installed on fixed or slow-moving structures, such as dams and marine vessels, and on mobile structures such as terrestrial vehicles and aircraft.

Abstract: A global navigation satellite sensor system (GNSS) and gyroscope control system for vehicle steering control comprising a GNSS receiver 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 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. The system includes gyroscopes for determining system attitude change with respect to multiple axes for integrating with GNSS-derived positioning information to determine vehicle position, velocity, rate-of-turn, attitude and other operating characteristics.

Abstract: An antenna is provided for GNSS and other applications and includes an adjustable-height vertical support PCB mounted on a ground plane and mounting a crossed-dipole radiating arm element assembly. The gain pattern of the antenna can be varied by constructing the vertical support PCB with different heights or adjusting the height and gain pattern in the field. Vehicles with significant pitch and roll can be provided with low-horizon tracking capability by providing a high-profile antenna configuration. Alternatively, low-profile configurations provide steeper gain pattern rolloff at the horizon for maximal multipath rejection and high accuracy. The droop angles of the radiating arm elements are also adjustable for varying the gain pattern and beamwidth. A matching and phasing network is connected to the radiating arm elements and provides a relatively constant input impedance for the various antenna configurations.

Abstract: A method for removing biases in dual frequency GNSS receivers circumvents the need for ionosphere corrections by using L2(P) in combination with either L1(P) or L1(C/A) to form ionosphere-free ranges. A table of biases is stored in microprocessor controller memory and utilized for computing a location using corrected ionosphere-free pseudo ranges. A system for removing biases in dual frequency GNSS receivers includes a dual frequency GNSS receiver and a controller microprocessor adapted to store a table of bias values for correcting pseudo ranges determined using L2(P) in combination with either L1(P) or L1(C/A).

Abstract: A GNSS-based, bidirectional mobile communication system includes a mobile unit, such as a vehicle or a personal mobile system, with GNSS (e.g., GPS) and Internet (worldwide web) access. A base station also has GNSS and Internet access, and provides differential (e.g., DGPS) correctors to the mobile unit via the Internet. The Internet communications link enables audio and/or video (AV) clips to be recorded and played back by the mobile unit based on its GNSS location. The playback function can be triggered by the mobile unit detecting a predetermined GNSS location associated with a particular clip, which can be GNSS position-stamped when recorded. Alternatively, clips can be generated by utilities and loaded by the application either from a personal computer or automatically over the Internet. Moreover, maps, vehicle travel paths and images associated with particular GNSS-defined locations, such as waypoints, can be updated and position-stamped on the data server.

Abstract: A feedback control law steers a reference phase that tracks the phase of a received code sequence. The reference phase clocks a track-reference signal consisting of a series of correlation kernels, over which data is extracted and then summed in various combinations. The correlation kernels are designed in such a manner that errors caused by multipath are eliminated or substantially reduced. Furthermore, the areas of the correlation kernels are balanced across level-transitions of a code and non-transitions to eliminate phase biases when tracking specific satellites. Extra care must be taken to balance the correlation kernels in this manner due to a little known aspect of GPS C/A codes. Specifically, not all C/A codes have the same ratio of level-transitions to non-transitions as has been assumed in prior art.

Abstract: A tightly-coupled printed circuit board (PCB) circuit includes components mounted on a PCB enabling smaller integrations using decoupled lines extending between reference layers, such as ground planes, form isolation islands on the PCB. The decouplers are capacitors, inductors and/or resistors in tandem with ground layers of the PCB. The isolated components can comprise high-frequency RF antennas and receivers, for example in a GNSS antenna-receiver circuit. Multiple antennas can be connected to one for more receivers with multiple, independent RF front end components by RF traces, which are either embedded within the PCB between the ground planes, or by surface microstrip antenna traces.