Abstract: Techniques are disclosed for providing at least one proposed alternative plan of travel of a vehicle are disclosed based upon data of at least one geographic region about at least one of global navigation satellite system (GNSS) spoofing and GNSS jamming. If a current path of travel of the vehicle intersects at least one geographic region of at least one of GNSS spoofing and GNSS jamming, then determining the at least one proposed alternative plan of travel of the vehicle. At least one of the at least one proposed alternative plan of travel includes a path of travel that does not intersect at least one geographic region of the at least one geographic region of at least one of GNSS spoofing and GNSS jamming. The determined at least one proposed alternative plan of travel is sent to the vehicle.

Abstract: A vehicle disturbance and isolation detection system is provided. The system includes at least one measurement sensor that is configured to generate measurement signals, at least one filter that is used to sort disturbance causes in the measured signals by frequencies, at least one controller that is used to compare the sorted signal to at least one threshold to determine if an event has occurred, a memory to store at least operating instructions for the at least one controller, a controller that is in communication with the memory and a communication system that is in communication with the at least one controller. The communication system is configured to transmit determined events to a remote location.

Abstract: Systems and methods for monitoring excessive delay gradients using long reference receiver separation distances are provided. In one embodiment, a ground-based system comprising a plurality of reference receivers configured to receive satellite signals. The ground-based system further comprises a processor coupled to a memory. The processor is configured to determine whether the line of sight of a newly available satellite is within a gradient. The processor is further configured to determine a monitor measurement using accumulated carrier data for each pair of reference receivers of a plurality of reference receiver pairs. The processor is further configured to combine monitor measurements for a subset of the plurality of reference receiver pairs into a monitor discriminator. The processor is further configured to output an alert when the monitor discriminator exceeds a threshold.

Abstract: A ground-based system to reduce the effect of interference, comprising a plurality of reference receivers, wherein the reference receivers are spaced a distance apart such that a single source of interference is unable to substantially interfere with a subset of the plurality of reference receivers, wherein the subset of the plurality of reference receivers includes at least two reference receivers; and a processing module communicatively coupled to the plurality of reference receivers and configured to receive data from each of the plurality of reference receivers, wherein the processing module is further configured to perform differential calculations on the data to calculate measurement corrections and estimated errors.

Abstract: An avionics system comprises one or more attitude sources, each configured to produce a respective calculated attitude solution; at least one magnetometer configured to measure magnetic field; and at least one attitude monitor configured to use the respective calculated attitude solution from one of the attitude sources to project the measured magnetic field estimate or an Earth Magnetic Field Model (EMFM) estimate such that the measured magnetic field estimate and the EMFM estimate are in a common shared frame. The at least one attitude monitor is further configured to determine a difference between the measured magnetic field estimate and the EMFM estimate in the common shared frame. The at least one attitude monitor is further configured to output an alert, which indicates that the respective calculated attitude solution used to project the measured magnetic field estimate or the EMFM estimate is in error, if the difference exceeds a predetermined threshold.

Abstract: Systems and methods for monitoring excessive delay gradients using long reference receiver separation distances are provided. In one embodiment, a ground-based system comprising a plurality of reference receivers configured to receive satellite signals. The ground-based system further comprises a processor coupled to a memory. The processor is configured to determine whether the line of sight of a newly available satellite is within a gradient. The processor is further configured to determine a monitor measurement using accumulated carrier data for each pair of reference receivers of a plurality of reference receiver pairs. The processor is further configured to combine monitor measurements for a subset of the plurality of reference receiver pairs into a monitor discriminator. The processor is further configured to output an alert when the monitor discriminator exceeds a threshold.

Abstract: A ground-based system to reduce the effect of interference, comprising a plurality of reference receivers, wherein the reference receivers are spaced a distance apart such that a single source of interference is unable to substantially interfere with a subset of the plurality of reference receivers, wherein the subset of the plurality of reference receivers includes at least two reference receivers; and a processing module communicatively coupled to the plurality of reference receivers and configured to receive data from each of the plurality of reference receivers, wherein the processing module is further configured to perform differential calculations on the data to calculate measurement corrections and estimated errors.

Abstract: An avionics system comprises one or more attitude sources, each configured to produce a respective calculated attitude solution; at least one magnetometer configured to measure magnetic field; and at least one attitude monitor configured to use the respective calculated attitude solution from one of the attitude sources to project the measured magnetic field estimate or an Earth Magnetic Field Model (EMFM) estimate such that the measured magnetic field estimate and the EMFM estimate are in a common shared frame. The at least one attitude monitor is further configured to determine a difference between the measured magnetic field estimate and the EMFM estimate in the common shared frame. The at least one attitude monitor is further configured to output an alert, which indicates that the respective calculated attitude solution used to project the measured magnetic field estimate or the EMFM estimate is in error, if the difference exceeds a predetermined threshold.

Abstract: A calibration method comprises providing a mounting fixture including a tray coupled to a frame, and an alignment measurement sensor removably coupled to the tray. An angular orientation of the tray is determined using the alignment measurement sensor removably coupled to the tray in a first position. The alignment measurement sensor is then moved to a second position on the tray that is rotated from the first position, and the angular orientation of the tray is determined using the alignment measurement sensor at the second position. An axis misalignment for at least two of a pitch axis, a roll axis, or a yaw axis of the alignment measurement sensor is then calculated to determine one or more misalignment factors. The one or more misalignment factors are then applied to correct for misalignment of the alignment measurement sensor.