Abstract: An antenna that provides a radiation pattern that is tilted relative to the perpendicular to the plane of the antenna is provided. The antenna may be located on an angled surface, but have its tilted beam reach maximum gain at its zenith. In alternative embodiments, the antenna may be substantially transparent or translucent allowing placement on a surface without blocking viewing through the surface.

Abstract: A system and method for detecting spoofing of a Global Navigation Satellite System (GNSS) system using a plurality of antennas. Signals received by at least two of the plurality of antennas are authentication by use of one or more of a carrier phase authentication procedure, a signal power authentication procedure, and/or a channel distortion authentication procedure.

Abstract: A system and method for detecting spoofing of a navigation system (NS) using a plurality of antennas. Carrier phase and CN0 measurements are obtains of a plurality of signals. The measurements are then double differenced and compared to predefined thresholds to determine whether a signal is authentic or not. Once sufficient authentic signals are identified, position and time is determined using the authenticated signals. Residuals are estimated for all signals. An average value of the residuals or the authenticated signals is calculated and is then removed from the residuals of the unauthenticated signals. Should the remainder exceed a predefined threshold, the signal is deemed to be spoofed. Otherwise, the signal is deemed to be authentic.

Abstract: A system and method for detecting spoofing of a Global Navigation Satellite System (GNSS) system using a plurality of antennas. Signals received by at least two of the plurality of antennas are authentication by use of one or more of a carrier phase authentication procedure, a signal power authentication procedure, and/or a channel distortion authentication procedure.

Abstract: A GNSS RHCP stacked patch antenna with wide dual band, high efficiency and small size is made of a molded high-permittivity material, such as ceramics, with a patterned cavity in the dielectric substrate. The perforated cavities in the substrate reduce the effective dielectric constant, increase the bandwidth and efficiency. The high-order modes can be manipulated through the design of cavities.

Abstract: In an example embodiment, a GNSS receiver may calculate protection levels for velocity and course over ground computed at a GNSS receiver. Specifically, the GNSS receiver may obtain Doppler measurements and variance measurements based on satellite signals received from at least five GNSS satellites. The GNSS receiver may utilize a least squares method to calculate the velocity states (e.g., x-velocity state, y-velocity state, and z-velocity state) and the clock bias for the GNSS receiver. The GNSS receiver may calculate the slope for each Doppler measurement on each velocity state. The GNSS receiver may then select the maximum slope for each velocity state and scale up the maximum slopes by a non-centrality parameter to calculate the protection level for each velocity state in the ECEF frame. The GNSS receiver may convert the velocity protection levels to NEU velocity protection levels to then calculate a protection level for course over ground.

Abstract: A relative navigation system comprising of a pair of Global Navigation Satellite System (GNSS) and Inertial Navigation System (INS) units that communicate to provide updated position, velocity and attitude information from a master to a rover. The rover unit produces a carrier based solution that enables the system to reduce the uncorrelated low latency position error between the master and the rover units to less than 50 cm.

Abstract: Systems and methods are provided for utilizing a connector to connect an external antenna to a mobile device. GNSS signals, associated with at least two different frequency bands, may be received at the external antenna and the GNSS signals may be transmitted to a connector module of the connector. The connector module may convert analog GNSS signals to generate digital radio frequency (RF) signals. The connector module may encrypt the digital RF signals to generate encrypted digital RF signals. The encrypted digital RF signals may be transmitted from the connector module to the mobile device. A multifrequency GNSS functionality module of the chipset may utilize decrypted digital RF signals to obtain GNSS raw measurements. The multifrequency GNSS functionality module and/or an application executing on the mobile device may utilize the GNSS raw measurements to compute position, velocity, and/or time (PVT).

Abstract: A system and method for detecting spoofing of global navigation satellite system (GNSS) signals using a single antenna is provided.

Abstract: A system and method for detecting spoofing of a Global Navigation Satellite System (GNSS) system using a plurality of antennas. Signals received by at least two of the plurality of antennas are authentication by use of one or more of a carrier phase authentication procedure, a signal power authentication procedure, and/or a channel distortion authentication procedure.

Abstract: Techniques are provided for GNSS carrier phase multipath mitigation using a blanked correlator in conjunction with a full correlator. A tracking loop may track a carrier of the GNSS signal utilizing the full correlator. A chip-edge accumulation (CEA) unit of the tracking loop may accumulate chip edges of a ranging code to generate CEA output. A blanked correlator may receive the CEA output to generate blanked correlator values. A running-sum filter may utilize the blanked correlator values to generate a running-sum value. A phase estimate may utilize the running-sum value to generate phase estimator output. In an exemplary embodiment, the blanked correlator operates as a monitoring correlator and the phases estimator output is the estimated carrier phase multipath error. In an exemplary embodiment, the blanked correlator provides input to the tracking loop and discriminator output is subtracted from the phase estimator output to generate the estimated carrier phase multipath error.

Abstract: In an example embodiment, motion is detected with an IMU utilizing standard deviation. Specifically, an IMU may obtains IMU measurements. An IMU motion detection process may accumulate a particular number of IMU measurements over a time interval to calculate an absolute magnitude of earth rate (ERimu) value and an absolute magnitude of normal gravity value (GNimu). The values calculated may be referred to as a sample. The IMU motion detection process may create sample rolling histories based on a particular number of samples, e.g., consecutive samples. The IMU motion detection process may then calculate standard deviation values for a sample rolling history based on the ERimu and GNimu values included in the sample rolling history. The IMU motion detection process may compare the standard deviation values to respective motion threshold values, which may be adaptive, to determine if a body of interest, e.g., vehicle, is moving or is stationary.

Abstract: Structures and techniques are disclosed that can be used to reduce or remove code multipath error in GNSS receivers by implementing one or more monitoring correlators in a multipath-error estimation and correction (MEC) module. The MEC module detects and provides for correction of correlation peak distortion. In exemplary embodiments, a code tracking loop integrates all-chip-edges of a PRN, and a narrow-correlator is used to update the tracking loop rate while a multipath estimation module implements a blanked correlator to estimate and remove the multipath bias from the code tracking loop measurements.

Abstract: A system and method generates a phase scintillation map that is utilized to de-weight satellite signal observations from GNSS satellites. One or more base stations each assign an index value to one or more GNSS satellite in view, where the index value indicates an adverse effect of ionospheric scintillation on signals received from the GNSS satellite. The values and identifiers may be transmitted to a server. The server utilizes the received information to generate the phase scintillation map that may include one or more scintillation bubbles, wherein a location of each scintillation bubble is based on the received information. The phase scintillation map is transmitted to one or more rovers. The rover determines if a pierce point associated with a selected GNSS satellite in view of the rover falls within the boundaries of a scintillation bubble. If so, satellite signal observations from the selected GNSS satellite are de-weighted.

Abstract: In an example embodiment, a GNSS receiver may calculate protection levels for velocity and course over ground computed at a GNSS receiver. Specifically, the GNSS receiver may obtain Doppler measurements and variance measurements based on satellite signals received from at least five GNSS satellites. The GNSS receiver may utilize a least squares method to calculate the velocity states (e.g., x-velocity state, y-velocity state, and z-velocity state) and the clock bias for the GNSS receiver. The GNSS receiver may calculate the slope for each Doppler measurement on each velocity state. The GNSS receiver may then select the maximum slope for each velocity state and scale up the maximum slopes by a non-centrality parameter to calculate the protection level for each velocity state in the ECEF frame. The GNSS receiver may convert the velocity protection levels to NEU velocity protection levels to then calculate a protection level for course over ground.

Abstract: A Global Navigation Satellite System (GNSS) receiver demodulates code shift keying (CSK) data utilizing a binary search. The GNSS receiver receives a signal including a pseudorandom noise (PRN) code modulated by code shift keying (CSK) to represent a symbol (i.e., CSK modulated symbol). The GNSS receiver maintains a plurality of receiver codes each representing a different shift in chips to the PRN code. The GNSS receiver performs a linear combination of portions of the receiver codes. In an embodiment, the GNSS receiver compares correlation power level value for respective portions of the receiver codes to demodulate the CSK data. In a further embodiment, the GNSS receiver compares the correlation power level values for portions of receiver codes with power detection threshold values to demodulate the CSK data. In a further embodiment, the GNSS receiver utilizes signs of the correlation power level values to demodulate the CSK data.

Abstract: A system operating in a dead reckoning mode accumulates relative yaw measurements, i.e., measurements of rotation about a z-axis, made by one or more over mechanization update intervals and produces dead reckoning mechanization update values. The system accumulates the values over a turn rate accumulation period, calculates a yaw rate and determines if the yaw rate exceeds a turn rate threshold. If so, the system directs an INS filter to perform a zero yaw rate update at the start of a next mechanization update interval, to correct for the z-axis drift errors of the gyroscopes based on the sensed rotation in the relative yaw measurements over the previous mechanization update interval. The system then sets the z-axis drift errors to zero. If the system determines that the yaw rate exceeds the turn rate threshold, the zero yaw rate update is not performed at the start of the next mechanization update interval.

Abstract: A switching mode front end surge protection circuit protects downstream devices from a load dump. Specifically, the switching mode front end surge protection circuit includes a metal-oxide-semiconductor field-effect transistor (MOSFET) that operates in either one of two modes based on an input voltage provided by an alternator. When the input voltage is less than a voltage threshold value, the MOSFET operates in a pass-through mode. When the input voltage is greater than the voltage threshold value, the MOSFET operates in a switching mode to oscillate between an on state and an off state.

Abstract: An antenna enclosure includes a sensor and a Global Navigation Satellite System (GNSS) antenna. Within the antenna enclosure, sensor data is combined with GNSS information to produce a RF communication signal, wherein the sensor data is out-of-band from the GNSS information. The RF communication signal is transmitted utilizing a GNSS antenna data link to a receiver side. On the receiver side, the RF communication signal is split into a GNSS RF path and a sensor RF path. The GNSS signals are transmitted to the GNSS receiver via the GNSS RF path. A sensor RF communication signal is de-modulated, and the sensor data is transmitted to the GNSS receiver. When the GNSS antenna data link is bi-directional, information may be transmitted from the GNSS receiver to the antenna enclosure via the GNSS antenna data link.

Abstract: A Global Navigation Satellite System (GNSS) receiver demodulates code shift keying (CSK) data utilizing a binary search. The GNSS receiver receives a signal including a pseudorandom noise (PRN) code modulated by code shift keying (CSK) to represent a symbol (i.e., CSK modulated symbol). The GNSS receiver maintains a plurality of receiver codes each representing a different shift in chips to the PRN code. The GNSS receiver performs a linear combination of portions of the receiver codes. In an embodiment, the GNSS receiver compares correlation power level value for respective portions of the receiver codes to demodulate the CSK data. In a further embodiment, the GNSS receiver compares the correlation power level values for portions of receiver codes with power detection threshold values to demodulate the CSK data. In a further embodiment, the GNSS receiver utilizes signs of the correlation power level values to demodulate the CSK data.