Abstract: A method for checking the integrity of the point positioning process obtained by determining the closest position, based on the adapted filtering of received GNSS signals, of a set of georeferenced reference positions for implementation on a mobile or fixed carrier, the method making it possible to check that the correlation function of the received GNSS signals is consistent with the selected reference position.

Abstract: A method for detecting a decoy source of a satellite radionavigation signal, the method being executed by a satellite radionavigation signal reception device comprising two receivers, the method comprising the steps of: for each signal received by the reception device and transmitted by a different satellite, estimating the phase of the signal received by each receiver, computing the estimated phase difference for each receiver, comparing the phase differences computed for multiple different satellites and, if at least two phase differences computed for two different satellites are substantially identical, concluding that a decoy source is present.

Abstract: A method for determining the point location of a vehicle stopped on one storage track among a set of storage tracks, using virtual beacons is provided. It determines and compares the likelihood of a plurality of hypotheses as to the stopped location of the vehicle, corresponding to a first set of NBe predefined virtual beacons Be(i), i varying from 1 to NBe, the respective positions of which are known in an amount of one virtual beacon per storage track, by correlating the GNSS geo-positioning signals received at various synchronization reset times of a second set by the GNSS receiver located on board the vehicle with predicted GNSS geo-positioning signals of replicas expected for the various positions of the virtual beacons of the first set at the various times. The detected holding position of the vehicle is the position that corresponds to the maximum likelihood.

Abstract: A method for determining the point location of a vehicle stopped on one storage track among a set of storage tracks, using virtual beacons is provided. It determines and compares the likelihood of a plurality of hypotheses as to the stopped location of the vehicle, corresponding to a first set of NBe predefined virtual beacons Be(i), i varying from 1 to NBe, the respective positions of which are known in an amount of one virtual beacon per storage track, by correlating the GNSS geo-positioning signals received at various synchronization reset times of a second set by the GNSS receiver located on board the vehicle with predicted GNSS geo-positioning signals of replicas expected for the various positions of the virtual beacons of the first set at the various times. The detected holding position of the vehicle is the position that corresponds to the maximum likelihood.

Abstract: Methods of checking the integrity of the estimation of the position of a mobile carrier are provided, the position being established by a satellite-based positioning measurement system, the estimation being obtained by the so-called “real time kinematic” procedures. The method verifies that the carrier phase measurement is consistent with the code pseudo-distance measurement. The method comprises a step of calculating the velocity of the carrier, at each observation instant, a step of verifying that at each of the observation instants, the short-term evolution of the carrier phase of the signals received on each of the satellite sight axes is consistent with the calculated velocity and a step of verifying that at each of the observation instants, the filtered position obtained on the basis of the long-term filtered measurements of pseudo-distance through the carrier phase is dependable.

Abstract: A system for detecting GNSS signal jammers to be positioned on a roadside, the system comprises: a first device for receiving a GNSS signal; a second device that is configured to measure at least one characteristic of a received GNSS signal and to detect, on the basis of at least one characteristic, interference in the GNSS signal caused by a jamming signal; a third device for triggering the capture of an image of the road if the GNSS signal is subject to interference caused by a jamming signal, the first device configured to receive, via a radio link, a sequence of a satellite radionavigation signal received by a vehicle and retransmitted by the vehicle to the system via the radio link.

Abstract: A railway positioning method, based on the movement of a train determined by a signal receiver of a satellite navigation system embedded onboard the train, and on the movement of the train determined by an odometer embedded onboard the train, and a map of the railway tracks, by determination of the ionospheric propagation bias corresponding to a propagation bias of the signal carrier phase of the satellite navigation system, comprises the steps of, by line of sight of the satellites of the navigation system: estimating the biased ionospheric drift by difference between an integrated Doppler term determined by the receiver and a biased estimation of the movement of the train by the odometer; estimating the odometer drift bias and the drift bias of the local clock of the receiver, by least squares resolution of the speed determined by the satellite navigation system, of the drift bias of the local clock of the receiver, and of the odometer drift bias; correcting the estimation of the ionospheric drift, by subtr

Abstract: The invention relates to a method and system for the validation of satellite-based positioning. The system comprises a radio navigation device (10) installed on board a mobile carrier (2), including a satellite geo-positioning device (12) able to receive a composite radio signal including a plurality of radio navigation signals each transmitted by a transmitting satellite and including time-synchronization and position-reference information, the radio navigation device being able to carry out processing of the received radio navigation signals to calculate first navigation information including information on the geographical position, speed and time of the carrier. The radio navigation device (10) is capable of transmitting baseband digitized signals (IF1, . . .

Abstract: A point location method for a vehicle moving on a constrained trajectory, implemented by a location device comprises tachometry means, odometry means, a group of at least one satellite geopositioning receiver and a time base synchronized to a satellite geopositioning system, the location device detecting the passage of the vehicle closest to a predetermined position by exploiting knowledge of the displacement of the vehicle, by predicting the form of a set of satellite geopositioning signals at the predetermined position and by testing the match between the predicted signals and those received by the group of at least one satellite geopositioning receiver, the displacement of the vehicle being determined from data supplied by the odometry means and a mapping of the trajectory.

Abstract: Methods of checking the integrity of the estimation of the position of a mobile carrier are provided, the position being established by a satellite-based positioning measurement system, the estimation being obtained by the so-called “real time kinematic” procedures. The method verifies that the carrier phase measurement is consistent with the code pseudo-distance measurement. The method comprises a step of calculating the velocity of the carrier, at each observation instant, a step of verifying that at each of the observation instants, the short-term evolution of the carrier phase of the signals received on each of the satellite sight axes is consistent with the calculated velocity and a step of verifying that at each of the observation instants, the filtered position obtained on the basis of the long-term filtered measurements of pseudo-distance through the carrier phase is dependable.

Abstract: Jammer location is based on detected powers received by at least one receiver of signals from the satellite navigation system on board a carrier, by estimation, for each satellite, of the power of the noise at the output of each receiver according to the bearing and distance with respect to the carrier, a calculation of the sum of estimated powers, and extraction of the local maxima in terms of bearing and distance by using a synthetic aperture antenna carrying out a coherent integration of received signals in the direction of each bearing angle by using the known movement of the carrier, in which estimation of the power of the noise at the output of each receiver uses a plurality of coherent integrators and non-coherent integrators, with durations matched to the transit time of a source in the beam of the antenna for various distances for the non-coherent integrators.

Abstract: A railway positioning method, based on the movement of a train determined by a signal receiver of a satellite navigation system embedded onboard the train, and on the movement of the train determined by an odometer embedded onboard the train, and a map of the railway tracks, by determination of the ionospheric propagation bias corresponding to a propagation bias of the signal carrier phase of the satellite navigation system, comprises the steps of, by line of sight of the satellites of the navigation system: estimating the biased ionospheric drift by difference between an integrated Doppler term determined by the receiver and a biased estimation of the movement of the train by the odometer; estimating the odometer drift bias and the drift bias of the local clock of the receiver, by least squares resolution of the speed determined by the satellite navigation system, of the drift bias of the local clock of the receiver, and of the odometer drift bias; correcting the estimation of the ionospheric drift, by subtr

Abstract: A system for detecting GNSS signal jammers to be positioned on a roadside, the system comprises: a first device for receiving a GNSS signal; a second device that is configured to measure at least one characteristic of a received GNSS signal and to detect, on the basis of at least one characteristic, interference in the GNSS signal caused by a jamming signal; a third device for triggering the capture of an image of the road if the GNSS signal is subject to interference caused by a jamming signal, the first device configured to receive, via a radio link, a sequence of a satellite radionavigation signal received by a vehicle and retransmitted by the vehicle to the system via the radio link.

Abstract: A point location method for a vehicle moving on a constrained trajectory, implemented by a location device comprises tachometry means, odometry means, a group of at least one satellite geopositioning receiver and a time base synchronized to a satellite geopositioning system, the location device detecting the passage of the vehicle closest to a predetermined position by exploiting knowledge of the displacement of the vehicle, by predicting the form of a set of satellite geopositioning signals at the predetermined position and by testing the match between the predicted signals and those received by the group of at least one satellite geopositioning receiver, the displacement of the vehicle being determined from data supplied by the odometry means and a mapping of the trajectory.

Abstract: The invention relates to a method and system for the validation of satellite-based positioning. The system comprises a radio navigation device (10) installed on board a mobile carrier (2), including a satellite geo-positioning device (12) able to receive a composite radio signal including a plurality of radio navigation signals each transmitted by a transmitting satellite and including time-synchronization and position-reference information, the radio navigation device being able to carry out processing of the received radio navigation signals to calculate first navigation information including information on the geographical position, speed and time of the carrier. The radio navigation device (10) is capable of transmitting baseband digitized signals (IF1, . . .

Abstract: Method of detecting interference in a satellite radio-navigation signal, characterized in that it comprises the following steps: determining a first temporal position for which the correlation between the said signal and a local spreading code, offset by the said position, is maximum; determining a plurality of measurements of correlation between the said signal and a local spreading code offset by a plurality of secondary temporal positions, the said plurality of secondary temporal positions and the said first temporal position being regularly spaced; determining, for a plurality of correlation measurement pairs formed by two measurements at two consecutive temporal positions, the phase difference between the two correlation measurements of the said pair; calculating an item of information representative of the standard deviation of the said phase difference; and comparing the said item of information with a detection threshold configured at least as a function of the ratio of the powers of the signal and

Abstract: Jammer location is based on detected powers received by at least one receiver of signals from the satellite navigation system on board a carrier, by estimation, for each satellite, of the power of the noise at the output of each receiver according to the bearing and distance with respect to the carrier, a calculation of the sum of estimated powers, and extraction of the local maxima in terms of bearing and distance by using a synthetic aperture antenna carrying out a coherent integration of received signals in the direction of each bearing angle by using the known movement of the carrier, in which estimation of the power of the noise at the output of each receiver uses a plurality of coherent integrators and non-coherent integrators, with durations matched to the transit time of a source in the beam of the antenna for various distances for the non-coherent integrators.

Abstract: Station for receiving satellite radio navigation signals having first wideband transceiver for receiving a specific signal transmitted by a transmitter/receiver and extracting therefrom at least one user radio navigation signal, a first centralized configured for determining a measurement of pseudo distance and a centralized calculator for calculating navigation information (PVT), the reception station having a first reference channel for receiving radio navigation signals having a directional antenna for forming a channel, a second processor for processing the radio navigation signal received by the directional antenna for forming a channel and a calculation unit that is suited to performing an improvement in reliability, an integrity check and authentication of the navigation information (PVT).

Abstract: A receiver of satellite signals serving for location (GNSS) adapted to be fixed on a support having at least one antenna able to receive the satellite signals serving for location. The antenna includes at least two mobile phase centers for determining a location on the basis of the satellite signals received, and a displacement device adapted for displacing the phase centers, for selecting one of the phase centers and for determining a position of the selected phase center with respect to the support.

Abstract: Method of detecting interference in a satellite radio-navigation signal determines the temporal position for which the correlation between the signal and a local spreading code offset by the position is maximum, calculating an information item representative of the intercorrelation between a first measurement of the correlation of the signal with a local spreading code at a first temporal position advanced relative to the temporal position of the maximum by a duration greater than the duration of a slot of the spreading code and a second measurement of the correlation of the signal with a local spreading code at a second temporal position delayed relative to the temporal position of the maximum by a duration greater than the duration of a slot of the spreading code, and comparing the item with a detection threshold configured at least as a function of the ratio of the powers of the signal and of the interference.