Abstract: A scintillation caused by ionospheric irregularities during Global Navigation Satellite System (GNSS) measurements is detected. A first input GNSS measurement corresponding to a navigation satellite and corresponding to a first carrier frequency and a second GNSS measurement corresponding to the navigation satellite and corresponding to a second carrier frequency, in which the second carrier frequency is different from the first carrier frequency, are received. A geometry-free combination (GFC) parameter based at least in part on the first input GNSS measurement, the second input GNSS measurement, the first carrier frequency, and the second carrier frequency is calculated. The occurrence of a scintillation caused by an ionospheric irregularity is determined based at least in part on the GFC parameter. In an embodiment of the invention, the dispersion of the GFC parameter over a specified time interval is determined. A scintillation is detected if the dispersion exceeds a specified threshold value.

Abstract: A digital video camera is placed on a vehicle. The video camera is attached to the vehicle and is directed to a surface at a certain angle to the surface. The camera angle can change while vehicle is in motion. The camera angle is constantly measured by angular sensor (i.e., inclinometer). Images of the surface are projected onto a video matrix and transformed into a sequence of digital frames that are formed at a pre-set time interval. A speed of the video camera relative to the surface is calculated as a ratio of an off-set between the adjacent frames and the time interval between the frames. Then a known relative speed of the vehicle can be corrected by multiplication of the height of the camera (above the surface) by a coefficient that equals a ratio of the known vehicle speed and the measured camera speed.

Abstract: Scintillations caused by ionospheric irregularities during Global Navigation Satellite System (GNSS) measurements are detected and mitigated. Detection is based at least in part on statistical properties of geometry-free combination parameters calculated from input GNSS measurements corresponding to the same navigation satellite and different carrier frequencies. Mitigation is based at least in part on ionosphere-free combination parameters calculated from input GNSS measurements corresponding to the same navigation satellite and different carrier frequencies. Depending on the number of satellites with detected scintillations, different algorithms are used to calculate values of target parameters from a set of ionosphere-free combination parameters or from a set of ionosphere-free combination parameters and the remaining input GNSS measurements.

Abstract: A method and apparatus for tracking products and providing product information receives information from a user device at a product server. A user scans a Quick Response code (QR code) using a mobile communication device which transmits product identification information from the QR code and user device information to a product server. The product server determines product information associated with the product identified by product identification information received from the user device. The product information is transmitted by the product server to the user device. The information received from the user device can also be used to track the location of products and acquire user information.

Abstract: A patch antenna includes a capacitive radiating patch, a ground plane, and vertical coupling elements electrically connected to defined portions of the capacitive radiating patch and the ground plane. The capacitive radiating patch includes an array of conductive segments along the periphery and within the interior of the capacitive radiating patch. Capacitors are electrically connected to specific conductive segments in a defined pattern. Vertical coupling elements electrically connect specific conductive segments along the periphery of the capacitive radiating patch to the ground plane. Vertical coupling elements can be conductors or defined combinations of resistors, inductors, and capacitors. Various embodiments of the patch antenna are configured for linear polarization and circular polarization. Relative to a conventional patch antenna of a similar size, a patch antenna with a capacitive radiating patch has a broader operational bandwidth and a broader radiation pattern in the forward hemisphere.

Abstract: A method and apparatus for determining the precise location of a target on a surface by utilizing a plurality of objects that are fixed in their position proximate to the location, thereby constituting a plurality of fixed reference points, upon which the target(s) resides or is otherwise located. The plurality of fixed references points are used either in conjunction with images of the target or certain distance measurements between the target and the fixed reference points to determine the precise location of the target(s) on the surface.

Abstract: The present invention relates to processing information generated by GNSS receivers received signals such as GPS, GLONASS, etc. GNSS receivers can determine their position in space. The receivers are capable of determining both coordinates and velocity of their spatial movement. When a receiver is used in any machine control systems, velocity vector heading (in other words, velocity vector orientation) should be determined along with velocity vector's absolute value. Angle, determining velocity vector orientation, is calculated based on velocity vector projections which are computed in navigation receivers. The accuracy of velocity vector orientation calculated based on velocity vector projections strongly enough depends on velocity vector's absolute value. To enhance the accuracy, a method of smoothing primary estimates of velocity vector orientation angles using a modified Kalman filter has been proposed.

Abstract: An architecture of a NAND Flash memory module interface controller (NAND-controller) provides access to data stored in an external NAND Flash memory module, and a method of booting firmware. NAND-controller automatically boots firmware from the NAND Flash memory into primary RAM of a system-on-a chip used for GNSS receivers. NAND-controller has a first external interface to connect NAND Flash memory, a second external interface to set parameters of booting firmware, and two internal interfaces: a high-speed one (system interface) and a low-speed one (control interface) to be connected to two types of SoC internal busses. Data exchange between the CPU and NAND Flash memory is implemented using a static RAM buffer which is a part of the NAND-controller and available for reading and writing via high-speed interface. Parameters of the first external interface are set and current state of data exchange process is controlled by the CPU.

Abstract: Multipath reception by an antenna is reduced by mounting the antenna on a semi-transparent ground plane that has a controlled distribution of layer impedance over a central region and a peripheral region. The central region includes a continuous conductive segment on which the ground element of the antenna is disposed. The distribution of the layer impedance over the peripheral region is configured by multiple conductive segments electromagnetically coupled by lumped circuit elements. A semi-transparent ground plane can be fabricated by depositing a metal film on a dielectric substrate and etching grooves into the metal film to form a desired pattern of conductive segments. Lumped circuit elements can be fabricated as discrete devices, surface mount devices, and integrated circuit devices. Various semi-transparent ground planes can be configured for linearly-polarized and circularly-polarized radiation.

Abstract: A method for measuring a signal-to-noise ratio when decoding Low Density Parity Check (LDPC) codes is provided. The method includes receiving from an input of a demodulator an input code word with “strong” or “weak” solutions, decoding the input code word in a LDPC decoder using a predetermined dependence of a mean number of iterations on the signal-to-noise ratio, recording a number of iterations performed during the decoding of the input code word, averaging derived values of the number of iterations for a specified time interval, estimating a signal-to-noise ratio based on averaged derived values of the number of iterations and based on the predetermined dependence of the mean number of iterations on the signal-to-noise ratio, and generating an output decoded code word.

Abstract: The present invention proposes a digital system and method of measuring (estimating) non-energy parameters of the signal (phase, frequency and frequency rate) received in additive mixture with Gaussian noise. The first embodiment of the measuring system consists of a PLL system tracking variable signal frequency, a block of NCO full phase computation (OFPC), a block of signal phase primary estimation (SPPE) and a first type adaptive filter filtering the signal from the output of SPPE. The second embodiment of the invention has no block SPPE, and NCO full phase is fed to the input of a second type adaptive filter. The present invention can be used in receivers of various navigation systems, such as GPS, GLONASS and GALILEO, which provide precise measurements of signal phase at different rates of frequency change, as well as systems using digital PLLs for speed measurements.

Abstract: An augmented image is generated by capturing a visual image of a site with a digital camera, generating a virtual image or associated information from a digital model of the site, and superimposing the virtual image or associated information on the visual image. To register the digital model with the visual image, a sensor pole is introduced into the field of view, and a combined visual image of the site and an optical target on the sensor pole is captured. The position and orientation of the sensor pole with respect to the site reference frame are measured by sensors mounted on the sensor pole; the position and orientation of the digital camera with respect to the sensor pole are calculated from image analysis of the optical target on the sensor pole; and the position and orientation of the digital camera with respect to the site reference frame are calculated.

Abstract: Navigation satellite receivers have a large number of channels, where phase discriminators and loop filter of a PLL operate in phase with data bits and control of numerically controlled oscillator (NCO) carried out simultaneously on all channels. Since symbol boundaries for different satellites do not match, there is a variable time delay between the generation of control signals and NCO control time. This delay may be measured by counting a number of samples in the delay interval. A proposed system measures non-energy parameters of the BPSK-signal carrier received in additive mixture with noise when a digital loop filter of PLL controls NCO with a constant or changing in time delay. A control unit controls bandwidth and a LF order by changing transfer coefficients based on analyzing estimated signal parameters and phase tracking error at a PD output.

Abstract: Dozers outfitted with manual or electric valves can be retrofitted with a control system for automatically controlling the elevation and orientation of the blade. No modification of the existing hydraulic drive system or existing hydraulic control system is needed. An arm is operably coupled to the existing joystick, whose translation controls the elevation and orientation of the blade. The arm is driven by an electrical motor assembly. Measurement units mounted on the dozer body or blade provide measurements corresponding to the elevation or orientation of the blade. A computational system receives the measurements, compares them to target reference values, and generates control signals. Drivers convert the control signals to electrical drive signals. In response to the electrical drive signals, the electrical motor assembly translates the arm, which, in turn, translates the joystick. If necessary, an operator can override the automatic control system by manually operating the joystick.

Abstract: An ultrasonic range sensor comprises at least one transducer adapted to generate an ultrasonic pulse having a first axis of transmission and detect a reflected signal that is associated with the ultrasonic pulse and propagates along the first axis of transmission. The ultrasonic range sensor also comprises a deflecting region adapted to reflect the reflected signal along a second axis different from the first axis of transmission. In one embodiment, the second axis is deflected from the first axis by a non-zero angle determined by a characteristic of the deflecting region.

Abstract: Navigation satellite receivers have a large number of channels, where phase discriminators and loop filter of a PLL operate in phase, with data bits and control of numerically controlled oscillator (NCO) carried out simultaneously on all channels. Since symbol boundaries for different satellites do not match, there is a variable time delay between the generation of control signals and NCO control time. This delay may be measured by counting a number of samples in the delay interval. A proposed system measures non-energy parameters of the BPSK signal carrier received in additive mixture with noise when a digital loop filter of PLL controls NCO with a constant or changing in time delay. A control unit controls bandwidth and a LF order by changing transfer coefficients based on analyzing estimated signal parameters and phase tracking error at a PD output.

Abstract: A patch antenna system with improved multipath resistance includes a top antenna assembly and a bottom antenna assembly. Each antenna assembly includes a radiator patch and a ground plane separated by a dielectric medium. The radiator patch on the top antenna assembly is excited by an exciter and an excitation circuit. The bottom antenna assembly is electromagnetically coupled to the top antenna assembly. The resonant frequency of the bottom antenna assembly is approximately equal to the resonant frequency of the top antenna assembly. Electromagnetic fields induced in the bottom antenna assembly are in opposite phase to the electromagnetic fields excited in the top antenna assembly. Amplitudes of electromagnetic fields induced in the bottom antenna assembly are subtracted from amplitudes of electromagnetic fields excited in the top antenna assembly, and multipath signals are suppressed. Single band and dual band antenna systems suitable for global navigation satellite systems can be implemented.

Abstract: A global navigation system includes a first navigation receiver located in a rover and a second navigation receiver located in a base station. Single differences of measurements of satellite signals received at the two receivers are calculated and compared to single differences derived from an observation model. Anomalous measurements are detected and removed prior to performing computations for determining the output position of the rover and resolving integer ambiguities. Detection criteria are based on the residuals between the calculated and the derived single differences. For resolving integer ambiguities, computations based on Cholesky information Kalman filters and Householder transformations are advantageously applied. Changes in the state of the satellite constellation from one epoch to another are included in the computations.

Abstract: The present invention relates to processing information generated by GNSS receivers received signals such as GPS, GLONASS, etc. GNSS receivers can determine their position in space. The receivers are capable of determining both coordinates and velocity of their spatial movement. When a receiver is used in any machine control systems, velocity vector heading (in other words, velocity vector orientation) should be determined along with velocity vector's absolute value. Angle, determining velocity vector orientation, is calculated based on velocity vector projections which are computed in navigation receivers. The accuracy of velocity vector orientation calculated based on velocity vector projections strongly enough depends on velocity vector's absolute value. To enhance the accuracy, a method of smoothing primary estimates of velocity vector orientation angles using a modified Kalman filter has been proposed.

Abstract: Disclosed is a technique for generating a three dimensional terrain map of a geographic area. Mobile units are equipped with satellite receivers (e.g., GPS receivers) for generating location data. A map generator uses the location data to generate a three dimensional terrain map. In one embodiment, the mobile units have primary uses other than mapping, and are traversing the geographic area to be mapped in connection with their primary function. The map generation process may be performed iteratively over time, as additional location data becomes available. During a time period when location data is unavailable for a portion of the three dimensional terrain map, the map generator may estimate the missing portion of the map using the available data. The estimated portion may later be updated with actual data as that data becomes available. The map may also contain enhancements based on enhancement data received by the map generator.