Abstract: The invention relates to a navigation system for aircraft comprising inertial sensors, a GNSS receiver and potentially a baro-altimeter. The measurements from the inertial sensors are hybridized with the code and phase measurements from the receiver within a main Kalman filter and, possibly, secondary filters. The said measurements are corrected for several types of errors, notably those due to the passage of the satellite signals through the ionospheric layers. The precision of the determination of the position of the aircraft is greatly improved, both in the horizontal plane and in the vertical direction. This is also the case for the corresponding protection radii, which allows margins to be created in order to satisfy the integrity constraints for the navigation solution.

Abstract: An inertial system measures the attitude of an aircraft consisting at least in determining the angle of pitch and/or the angle of heading and/or the angle of roll of the aircraft, each of the said angles of attitude being determined by successive double integration of their second derivative. A pair of accelerometers to determine the angle of pitch being are disposed on either side of the centre of gravity along an axis substantially merged with the longitudinal axis of the aircraft. A pair of accelerometers to determine the angle of heading are disposed on either side of the centre of gravity along an axis substantially merged with the transverse axis of the aircraft. A pair of accelerometers to determine the angle of roll are disposed on either side of the centre of gravity along a vertical axis perpendicular to the plane formed by the other axes.

Abstract: Method for determining navigation parameters of an aircraft, characterized in that it consists at least in determining the geographic speed {right arrow over (V)}, expressed in a given local fixed coordinate system {{right arrow over (i)}, {right arrow over (j)}, {right arrow over (k)}}, based on the measurements m, of carrier phase increments ??i of the radio navigation signals originating from a plurality of radio navigation satellites in sight of said aircraft, each of said measurements mi constituting an estimate of the relative speed of said aircraft relative to said satellite projected onto the sight axis linking the aircraft to the satellite, each of said measurements m, being compensated by the apparent radial speed of the satellite.

Abstract: The present invention relates to an air navigation device with inertial sensor units and radio navigation receivers, and is characterized in that its radio navigation receivers are multiple-constellation receivers and in that their output data are hybridized with the data from the inertial sensor units. According to another feature of the invention, at least some of the inertial sensor units are of MEMS type.

Abstract: Hybrid system (1) comprising an elementary hybrid system (2) comprising an extended processing module CALC (100) determining a first protection radius of the hybrid system RHG1, associated with a position quantity G, using a first extended variance/covariance matrix MHYPE1 as a function of a predetermined first false alarm probability PFA1, of a predetermined non-integrity level PNI and of a predetermined first probability PP1 of occurrence of an undetected hardware failure of a satellite positioning receiver.

Abstract: The invention relates to a navigation system for aircraft comprising inertial sensors, a GNSS receiver and potentially a baro-altimeter. The measurements from the inertial sensors are hybridized with the code and phase measurements from the receiver within a main Kalman filter and, possibly, secondary filters. The said measurements are corrected for several types of errors, notably those due to the passage of the satellite signals through the ionospheric layers. The precision of the determination of the position of the aircraft is greatly improved, both in the horizontal plane and in the vertical direction. This is also the case for the corresponding protection radii, which allows margins to be created in order to satisfy the integrity constraints for the navigation solution.

Abstract: The invention pertains to the monitoring of the integrity of position and speed information arising from a hybridization between an inertial reference system and a satellite-based positioning receiver. The invention relates more precisely to a navigation apparatus known in the art by the name INS/GNSS system (for “Inertial Navigation System” and “Global Navigation Satellite System”) hybridized in closed loop.

Abstract: The invention relates to a closed loop hybridizing device comprising a Kalman filter bank, a virtual platform, a device to calculate pseudo-measurements estimated a priori. The Kalman filter bank comprises a principal Kalman filter adapted to the calculation of corrections to be applied to inertial measurements starting from all available pseudo-measurements, and n secondary Kalman filters adapted to the calculation of corrections to be applied to inertial measurements from a sub-set of available pseudo-measurements. The corrections originate from either the principal Kalman filter when no pseudo-measurement is erroneous or the secondary Kalman filter not affected by an erroneous pseudo-measurement. The corrections are applied simultaneously to inertial measurements and to the input to all other Kalman filters in the Kalman filter bank. In particular, the invention applies to a hybridizing device using information provided by an inertial unit and a satellite navigation system, for example a GPS system.

Abstract: The invention pertains to the monitoring of the integrity of position and speed information arising from a hybridization between an inertial reference system and a satellite-based positioning receiver. The invention relates more precisely to a navigation apparatus known in the art by the name INS/GNSS system (for “Inertial Navigation System” and “Global Navigation Satellite System”) hybridized in closed loop.

Abstract: The present invention relates to a method of improving the integrity and safety of a system, this method making it possible, on the one hand, to detect and to locate an anomaly of a system, and on the other hand to estimate the impact of such an anomaly on the degradation of performance, with a view to attaining the safety level required and to making the data provided by this system safe, and this method is characterized in that it consists, in a system comprising sub-assemblies, in monitoring the proper operation of sub-assemblies by checking their respective transfer functions in the operational mode with the aid of stimuli dispatched to these sub-assemblies.

Abstract: The device is for monitoring the integrity of the position and speed information supplied by a hybrid system comprising an inertial unit INS readjusted using a GNSS satellite positioning receiver by means of a Kalman hybridization filter using a readjustment gain K and an evolution matrix F.

Abstract: The invention relates to a closed loop hybridising device comprising a Kalman filter bank, a virtual platform, a device to calculate pseudo-measurements estimated a priori. The Kalman filter bank comprises a principal Kalman filter adapted to the calculation of corrections to be applied to inertial measurements starting from all available pseudo-measurements, and n secondary Kalman filters adapted to the calculation of corrections to be applied to inertial measurements from a sub-set of available pseudo-measurements. The corrections originate from either the principal Kalman filter when no pseudo-measurement is erroneous or the secondary Kalman filter not affected by an erroneous pseudo-measurement. The corrections are applied simultaneously to inertial measurements and to the input to all other Kalman filters in the Kalman filter bank. In particular, the invention applies to a hybridising device using information provided by an inertial unit and a satellite navigation system, for example a GPS system.

Abstract: The device is for monitoring the integrity of the position and speed information supplied by a hybrid system comprising an inertial unit INS readjusted using a GNSS satellite positioning receiver by means of a Kalman hybridization filter using a readjustment gain K and an evolution matrix F.

Abstract: The invention relates to an internal platform hybridized with a GPS receiver. The hybridization is achieved through a Kalman filter through which a new hybrid position D-HYB is estimated on the basis of a noted deviation between pseudo-distance measure by the receiver between the receiver and the various satellites and corresponding distances computed by the inertial platform between the platform and the same satellites. In this filtering, the distance increment from one measurement instant to the next instant, between the pseudo-distance previously measured by the receiver on a satellite axis of a deviation and the new pseudo-distance measured by the receiver on a satellite axis of a deviation and the new pseudo-distance measured by the receiver on this axis, is the phase variation ??=?(t)??I (t?1) of a digital oscillator between the two measurement instants, this variation being referred to distance along the satellite axis.

Abstract: To improve the accuracy of altitude measurement, the inertial unit (C_INERT) is associated with a radiosonde supplying a height (HAUT_ALT) of the aircraft relative to the ground and a terrain database (DTED) supplying an altitude of the ground (ALT_GND) at the horizontal position (POS_HOR_HYB) of the aircraft delivered by the inertial unit. The inertial unit supplies an altitude (ALT_HYB) which is corrected based on the values supplied by the radiosonde and the terrain database. A radius of protection (RPalt_hyb_cor) of the altitude thus corrected is computed. For this computation of protection radius, particular use is made of a computation of the altitude dispersion of the terrain around the horizontal position of the aircraft, in a circle delimited on the basis of the radius of protection of the horizontal position (RPpos_hor_hyb), supplied by the inertial unit at the same time as the horizontal position.

Abstract: The invention relates to an inertial system hybridised with a GPS receiver. Said hybridisation is carried out by Kalman filtering, by means of which is a new hybrid position D HYB is estimated from a deviation observed (Yo) between (i) pseudo-distances measure by the receiver between the receiver and the different satellites and (ii) the corresponding distances calculated by the inertial system between the system and the same satellites. In the aforementioned filtering, the distance increment from one measuring time to the next, between (i) the pseudo-distance previously measured by the receiver on a satellite axis in order to observe a deviation and (ii) the new pseudo-distance measured by the receiver on said axis, is the phase variation &Dgr;&PHgr;=&PHgr;i(t)−&PHgr;i(t-1) of a digital oscillator between the two measuring times, said variation being brought along the length of the satellite axis in terms of distance.