Hemisphere | Date: 2014-04-09
A device for determining the position and orientation of a first body with respect to a second body uses a plurality of radio frequency (RF) transmitters on the first body to transmit a short range signal to one or more RF antennas on the second body. The first and second body are near each other and can be moveably coupled. A receiver circuit on the second body uses the plurality of RF signals received by the RF antennas to determine the position and orientation of the first body with respect to the second body. In some embodiments one or more GNSS antennas mounted to the second body will provide the GNSS coordinate system and location such that the position and orientation of both the first body and the second body can be referenced to the GNSS global coordinate system.
Hemisphere | Date: 2015-03-12
Disclosed is a device and method for determining the direction of a false Global Navigation Satellite System (GNSS) satellite signal transmitter. False GNSS satellite signals can be used malevolently to take control of a rigid body such as a vehicle or ship that is using GNSS satellite signals for navigation. The GNSS device according to the invention computes a plurality of range differences, where each range difference is the difference between a range from a first GNSS satellite to a first GNSS antenna, and the range from the first GNSs satellite to a second GNSS antenna. Each of the plurality of range differences is correlated to a rotation angle of a baseline vector extending from the first GNSS antenna to the second GNSS antenna. The rotation angles and their corresponding range differences can be used to indicate the direction of the false GNSS satellite signal transmitter.
Hemisphere | Date: 2015-03-04
Disclosed is a system and method for detecting false Global Navigation Satellite System (GNSS) satellite signals. False GNSS satellite signals can be used malevolently to take control of a body such as a vehicle or ship that is using GNSS satellite signals for navigation. In some embodiments a GNSS attitude system is used to detect the false GNSS satellite signals. The GNSS attitude system measures the code or carrier phase of the GNSS satellite signals at two or more antennas to detect the false GNSS satellite signals. In some embodiments the attitude system computes first measured and second estimated carrier phase differences in order to detect the false GNSS satellite signals. The attitude system may compute the attitude of a baseline vector between the two antennas. Once false GNSS satellite signals are detected, the method can include preventing the attitude determining system from outputting position or location data.
Hemisphere | Date: 2015-02-27
A locally enhanced GNSS wide-area augmentation system is provided. The system includes a global reference processing center and a wide-area reference network formed of wide-area reference stations and GNSS satellites. The global reference processing center is in communication with the wide-area reference network in order to receive global network data and form global correction data. The system also includes a local reference processing center and a local reference network having reference stations and a rover receiver that communicate with GNSS satellites. The local reference processing center is in communication with the local reference network in order to receive local network data and form local enhancement data. The system also includes a communication link to send correction data formed of global correction data and local enhancement data to the rover receiver.
Hemisphere | Date: 2014-04-21
An integrated machine guidance system for guiding a critical device of a machine includes global navigation satellite system (GNSS) antennas, a GNSS receiver, a guidance controller, and a wireless communication system enclosed in a housing. The guidance controller is adapted to compute an actual position of the critical device and determine a direction that the critical device should move to arrive at a desired position. The housing may be coupled to a mounting element, which is attached to the critical device. A display unit is in communication with the guidance controller, and is coupled to the housing so that it is visible to an operator in the cab of the machine. The guidance controller may communicate with another display unit located remote from the housing via the wireless communication system. Each of the display units can provide an indication of the direction that the critical device should move.
Hemisphere | Date: 2014-10-17
An antenna-receiver communication system comprises an antenna conductor, antenna, and intelligent antenna controller. The intelligent antenna controller and antenna are connected via a conductor for providing power to the antenna from the intelligent antenna controller, and a received signal from the antenna to the intelligent antenna controller. The intelligent antenna controller is configured to provide voltage to the antenna for its operation, and to systematically alter the provided voltage level to communicate information to the antenna. The antenna is configured to communicate messages to the intelligent antenna controller by systematically altering the current consumed by the antenna. Both the intelligent antenna controller and antenna are configured to decode received messages and act on them. A method for communication between an intelligent antenna controller and antenna utilizing patterns of voltage and current fluctuation over the conductor providing power from the intelligent antenna controller to the antenna is also provided.
Hemisphere | Date: 2014-03-14
GNSS signals are centered around two bands, L1 and L2, and antennas must cover both these bands for good RTK performance. GPS is at a lower frequency in both bands than the Russian GLONASS system. What is described herein is a method of constructing a low profile dual frequency wideband antenna with excellent polarization and signal reception for both GPS and GLONASS. This technique minimizes the impact of tolerances of the dielectrics, thicknesses and tuning by optimal construction.
Hemisphere | Date: 2014-12-31
Disclosed is GNSS extension device for use with portable devices in a Mapping and Geographical Information System (MGIS). The GNSS extension device includes a dual frequency GNSS antenna, a GNSS processing board for tracking and processing GNSS signals, a battery to sustain the GNSS processing board and antenna, and an application to manage GNSS device and position solution usage flow. The device also includes a portable device receiver to receive and retain a portable computing device, wherein the portable computing device executes instructions provided by the application. Thus the combination of the GNSS extension device and the portable computing device becomes a MGIS-like device.
Hemisphere | Date: 2014-12-23
The disclosed global navigation satellite system (GNSS) devices and methods group GNSS satellite signals from different GNSS constellations, as well as other signals of interest, into sub-bands, also called superbands, by signal frequency for analog filtering and processing, and then further divides each superband for additional processing in the digital domain. Each superband is a frequency range that can include GNSS satellite signals from one, two, three, or more than three, GNSS constellations. Using multiple parallel processing channels allows multiple signal frequency bands that cover a wide bandwidth to be divided into narrower superbands for processing, which increases the processing abilities within the superbands and allows out-of-band interference between superbands to be eliminated. Thus the GNSS satellite signals are divided for processing according to frequency, not according to the originating GNSS satellite constellation.
Hemisphere | Date: 2014-07-23
A Global Navigation Satellite System (GNSS) electronic circuit is described that uses an antenna and a fractal ground plane conductor or a fractal counterpoise. Some embodiments of the electronic circuit include a first ground plane conductor portion on a first electronic substrate, and a second ground plane conductor portion on a second electronic substrate. The second ground plane conductor portion is shaped to include at least one fractal pattern. The fractal pattern of the second ground plane conductor portion makes the ground plane seem electrically larger than it is. The fractal ground plane conductor portion minimizes the reception of GNSS satellite signals below the antenna, and improves the reception of signals from low elevation GNSS satellites above the horizon.