A system or method for generating or distributing GNSS corrections can include or operate to: generate a set of corrections based on satellite observations, wherein each correction of the set of corrections comprises an area associated with the correction, a tag, and correction data; update a set of stored corrections with the set of received corrections based on a tag associated with each correction of the set of stored corrections and the tag associated with each correction of the set of received corrections; and transmit stored corrections of the set of stored corrections to the GNSS receiver when the area associated with the stored corrections matches the locality of the GNSS receiver.

A communication apparatus for subsequent installation in a vehicle and/or for mobile use, having: a transceiver having an antenna for wireless data transmission, a GNSS receiver having an antenna for receiving signals from a global satellite navigation system, an inertial measurement unit, and a housing enclosing the transceiver, the GNSS receiver and the inertial measurement unit at least in part. The communication apparatus is configured to use data captured by the inertial measurement unit and/or the GNSS receiver to perform motion detection, in order to ascertain a motion pattern, and to perform or prevent a data transmission by the antenna for the purpose of wireless data transmission as a function of the ascertained motion pattern. Furthermore, the a method for execution using such a communication apparatus is disclosed.

A radio receiver includes a downconverter for downconverting dual sideband signals such as Binary Offset Carrier (BOC) signals from multiple sources to produce an upper and a lower sideband signal, and chip-matched filters for filtering each of the sideband signals. The output of each filter is provided to a series of separate channels, one for each source, where there are at least Early, Prompt and Late gates. Each gate has a nearest-neighbour sampler and a multiplier for multiplying with an appropriate part of a spreading code, a mixer for removing Doppler or other frequency offsets and an integrator. The invention provides a means for demodulating signals such as BOC modulated satellite navigation signals in an efficient manner by using a single downconverter for the received signals of interest from the multiple sources.

A radio receiver includes a downconverter for downconverting dual sideband signals such as Binary Offset Carrier (BOC) signals from multiple sources to produce an upper and a lower sideband signal, and chip-matched filters for filtering each of the sideband signals. The output of each filter is provided to a series of separate channels, one for each source, where there are at least Early, Prompt and Late gates. Each gate has a nearest-neighbour sampler and a multiplier for multiplying with an appropriate part of a spreading code, a mixer for removing Doppler or other frequency offsets and an integrator. The invention provides a means for demodulating signals such as BOC modulated satellite navigation signals in an efficient manner by using a single downconverter for the received signals of interest from the multiple sources.

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.

A GNSS receiver includes a demodulation module, a position calculation module, a storage, and a determination module. The demodulation module receives the GNSS signal and acquires a navigation message. The position calculation module performs positioning calculation based on a propagation delay which is a time until a GNSS signal transmitted from a GNSS satellite reaches an antenna. The storage stores reception timing (reference timing) of a message of a predetermined type in the navigation message. The determination module determines that a GNSS signal including the navigation message is a spoofed GNSS signal when the difference between the reception timing of the next and subsequent messages of the same type predicted from the reference timing and the reception timing of the same type of message received after the reference timing is outside the scope of the time threshold.

A method of analyzing a ground-based augmentation system (GBAS) signal, comprising: transmitting at least one GBAS message burst; receiving the GBAS message burst, and performing a power measurement at symbol times of the GBAS message burst. Further, a test system for testing a ground-based augmentation system is described.

A receiver device to receive an incoming radio frequency (RF) satellite signal from a satellite vehicle includes a processor and computer-readable storage media. The computer-readable storage media is communicably connected to the processor and has instructions stored thereon that, when executed by the processor, causes the processor to track the incoming RF satellite signal in code phase and carrier frequency, the incoming RF satellite signal having a primary pseudorandom (PRN) code and a secondary PRN code modulated thereon, generate an encoded sequence of dot product values of adjacent integrated in-phase (I) and quadrature-phase (Q) components of the incoming RF satellite signal, compare the encoded sequence with expected secondary code chip transitions, determine a secondary code phase for the secondary PRN code based on the comparison, and coherently integrate the secondary code phase with the incoming RF satellite signal to increase an integration interval.

Aspects of the present disclosure relate to identifying points of interest by generating and storing virtual geofence information that is captured around a physical structure based in part on global positioning system (GPS) data from a plurality of devices that is then processed to identify GPS trajectory and kernel density estimation. Specifically, the techniques include receiving, at the network-based control computer, GPS data from a plurality of devices and grouping the GPS data from the plurality of devices to generate GPS trajectory information for each group of the plurality of devices. Based on the GPS trajectory information, the network-based control computer may calculate kernel density estimation and determine an isoline on a virtual map for the each group of the plurality of devices. By overlaying the isoline data on a geographic coordinate information of a physical structure, the network-based control computer may generate a virtual geofence around the physical structure and store, in a memory, geofence information for the facility.

A computer implemented method of validating an output from a GNSS at a receiver including a fusion system comprising location sensors. A location estimate and a location error estimate are computed. A navigation update including a sensor location estimate and sensor location error estimate is also computed with the fusion system based on sensor measurements from the location sensors. A determination is made as to whether or not GNSS filters should be applied based at least on the location estimate, the sensor location estimate, and the sensor location error estimate. When GNSS filters should be applied, the location estimate and/or the location error estimate may be adjusted or rejected and a new navigation update may be computed with the fusion system based on the adjustment or rejection. When the GNSS filters should not be applied, the new navigation update is computed with the location estimate and the location error estimate.