Abstract: A method for detecting the distortion of a GNSS signal transmitted by at least one GNSS satellite and received by at least one GNSS receiver, said distortion being caused by a GNSS signal generation defect, includes at least the following steps: a step for determining at least one autoregressive parametric model of the GNSS signal at the output of a correlation stage that said GNSS receiver includes; a step for computing at least one linear prediction error e(n) between said output signal of the correlation stage and said autoregressive parametric model; at least one step for comparing the linear prediction error to a detection threshold; and, a step for deciding on the distortion of the transmitted GNSS signal in the case where the linear prediction error exceeds said detection threshold.

Abstract: A system for augmenting the availability and performance of a satellite geolocation system includes at least: a behaviour model of at least one of the satellites of said geolocation system incorporating new parameters with which to augment the operating range of said system; and an indicator of the deviation between said model and the real behaviour of said geolocation satellite, so as to enable the receiver to continue to use said geolocation satellite to determine its position, using the behaviour model, and outside the nominal operating range of the geolocation system. The parameters of the behaviour model include at least a model of distortion of the code chips transmitted by said navigation satellite to said receiver, or a model of distortion of the phase of the signal transmitted by said navigation satellite to said receiver.

Abstract: A space navigation receiver (NR) comprises i) a radiofrequency processing module (PM1) tasked both with converting radio navigation signals transmitted by a satellite navigation system into digital navigation signals, and with converting auxiliary radio signals representative of navigation information about said system into auxiliary digital signals, ii) a digital processing module (PM2) tasked with periodically acquiring the digital navigation signals by sub-sampling the received radio signal, then processing the acquired signal samples (resulting from this sub-sampling) in order to produce raw measurements from these samples, from auxiliary digital signals, and from location points, and iii) a location module (LM) tasked with determining location points based on raw measurements, demodulated navigation data initially contained within the digital navigation signals in a modulated form, and orbital force models.

Abstract: A method for the geolocation of a device transmitting a signal containing at least one message to a plurality of relay satellites in a medium earth orbit, visible from said device, receiving said message and transmitting it to processing means, comprises at least the following steps: determination of the times of reception of the message by the relay satellites; determination of the pseudo-distances between the device and the relay satellites; searching for and acquiring a minimum number N of satellite radio navigation signals; determination of the time lags between the transmission of the radio navigation signals and their reception by the said device; broadcasting by the device of these time lags in the message; and, determination of the position of the device from at least the pseudo-distances, from the time lags and from the positioning coordinates of the relay satellites and of the radio navigation satellites.

Abstract: The present invention relates to a method of validating the detection of a correlation peak between a signal transmitted by a plurality of navigation satellites and received by an RNSS satellite radio navigation receiver, said signal corresponding to a sum of signals each sent by a satellite and each modulated by a spread spectrum signal characteristic of said satellite and a local replica generated by said receiver of a spread spectrum signal characteristic of a satellite that is being looked for. Said method includes a step of determining the correlation function 3 as a function of time between said received signal and said local replica and further includes a step of comparing said correlation function 3 with the theoretical autocorrelation function 2 as a function of time of said spread spectrum signal characteristic of said satellite that is being looked for.

Abstract: A method for optimizing the acquisition phase of a spread-spectrum signal by a mobile receiver includes searching for the path having the maximum energy for different frequency assumptions and among all the positive trend paths of said frequencies between two initial and final instants marking the beginning and the end of a coherent signal integration.

Abstract: Satellites of a satellite positioning system broadcast within the navigation signals ephemeris data having a certain period of validity. At a mobile station, ephemeris data are required for position-fixing. In assisted satellite positioning systems, acquisition of navigation signals emitted by the satellites is facilitated as assistance data are provided to the mobile station. At a server station, a request for assistance data issued by the mobile station is received, and the server station transmits ephemeris data as part of the assistance data to the mobile station in response to its request. Upon receiving the request for assistance data issued by the mobile station, the server station decides whether the mobile station could achieve a specified position fix accuracy if the mobile station was provided with the broadcast ephemeris data. In the positive, the server station transmits the broadcast ephemeris data to the mobile station.

Abstract: A mobile terminal (UE) comprises means (CR) for acquiring pseudo-random codes modulating signals received from positioning satellites (SN) in view belonging to a constellation (CS) and related to a reference time, and computation means (MC1-MC3) for determining its position received from the acquired codes and from navigation data contained in the signals.

Abstract: The present invention relates to a method of updating the clock bias between the common clock of the satellites of a radio navigation satellite system and the clock of a radio station of an asynchronous cellular radiotelephone system including a mobile device including a radio navigation satellite system receiver for receiving satellite data supplied by at least four satellites and an assistance server for improving the acquisition of satellite data by the mobile device.

Abstract: A space navigation receiver (NR) comprises i) a radiofrequency processing module (PM1) tasked both with converting radio navigation signals transmitted by a satellite navigation system into digital navigation signals, and with converting auxiliary radio signals representative of navigation information about said system into auxiliary digital signals, ii) a digital processing module (PM2) tasked with periodically acquiring the digital navigation signals by sub-sampling the received radio signal, then processing the acquired signal samples (resulting from this sub-sampling) in order to produce raw measurements from these samples, from auxiliary digital signals, and from location points, and iii) a location module (LM) tasked with determining location points based on raw measurements, demodulated navigation data initially contained within the digital navigation signals in a modulated form, and orbital force models.

Abstract: The present invention concerns a method of optimization of processing of signals from satellite positioning systems in the case where at least two satellite systems cohabit and are utilized to obtain the position of a receiver. One of the systems is given preference on the basis of a criterion of performance and the satellites of the other systems are eliminated that are situated at an azimuth/elevation angle difference less than a threshold relative to the satellites of the preferred system.

Abstract: “Satellites of a satellite positioning system broadcast within the navigation signals ephemeris data having a certain period of validity. At a mobile station, ephemeris data are required for position-fixing. In assisted satellite positioning systems, acquisition of navigation signals emitted by the satellites is facilitated as assistance data are provided to the mobile station. At a server station, a request for assistance data issued by the mobile station is received, and the server station transmits ephemeris data as part of the assistance data to the mobile station in response to its request. Upon receiving the request for assistance data issued by the mobile station, the server station decides whether the mobile station could achieve a specified position fix accuracy if the mobile station was provided with the broadcast ephemeris data. In the positive, the server station transmits the broadcast ephemeris data to the mobile station.

Abstract: A receiver (R) for use in a user mobile terminal (U) in a satellite positioning system having a constellation of satellites (S) in which the receiver (R) acquires data from a satellite related to the position of the mobile terminal (U). A MEMS device (M) is incorporated in the receiver (R) and is adapted for detecting the absolute value ({circumflex over (V)}u) of the speed of the mobile terminal (U) and subsequently providing said value to the receiver (U). Means are provided for computing, by or for the receiver (R), the value corresponding to the vector components (Vux, Vuy, Vuz) of the speed of the mobile terminal which in turn make possible the Doppler effect related to the users speed is obtained.

Abstract: The present invention provides a method of acquisition of satellite data by a mobile device including a radio navigation satellite system (RNSS) receiver. The method includes: the receiver receiving a signal transmitted by a plurality of satellites and corresponding to a sum of signals each transmitted by a satellite and each modulated by a spread spectrum signal characteristic of said satellite; the receiver generating a plurality of local duplicates each of which is the duplicate of a spread spectrum signal characteristic of a satellite; correcting the frequency of each of the local duplicates by compensating the Doppler effect of each of the satellites; summing the plurality of corrected duplicates; and determining the correlation function as a function of time between the sum of the plurality of corrected duplicates and the satellite data signal.

Abstract: A terminal, in particular a mobile terminal, comprises means for processing a positioning signal coming from a satellite positioning system, means for computing direct and inverse Fourier transforms, wireless communication means using OFDM modulation, and priority management means for assigning resources of the direct/inverse Fourier transform computation means either to the positioning signal processing means or to the wireless communication means.

Abstract: The invention relates to a satellite radio navigation terminal using services of a cellular communication network, wherein the pre-location consists in locating the terminal in at least one network cell and the inventive method consists in forming a database (24) compiling location information items of the network cells transmitted by the cellular network terminals (4), wherein said database comprises, for each cell, at least one identifier and information item on the location thereof, and in pre-locating (23) the terminal according to the identifier thereof and information items contained in the database. Satellite positioning systems combining satellite communication techniques and satellite locating techniques such as, for example A-GPS system, are also disclosed.

Abstract: The present invention relates to a method of updating the clock bias between the common clock of the satellites of a radio navigation satellite system and the clock of a radio station of an asynchronous cellular radiotelephone system including a mobile device including a radio navigation satellite system receiver for receiving satellite data supplied by at least four satellites and an assistance server for improving the acquisition of satellite data by the mobile device.

Abstract: The present invention relates to a method of synchronizing base stations of a terrestrial cellular communication system using a satellite component.

Abstract: The present invention proposes to use optimally a location method based on a WIFI type short-range telecommunication system and a satellite location system. The short-range telecommunication system is used to locate the terminal accurately within the building in which it is situated. The method uses a cartographic representation of the buildings in order to deduce from the position of the terminal a set of satellites that could be received by the terminal. The satellites are then acquired to synchronize the terminal to the satellite system. That synchronization is then used when the terminal leaves the building to acquire as quickly as possible the set of satellites of the satellite navigation constellation.

Abstract: The inventive device is used for locating one or several mobile terminals (UE1, UE2, UE3) situated in cells (C1, C2, C3) of an asynchronous mobile communications network (R) controlled by the base stations (BTS1, BTS2, BTS3), wherein said network comprises an assistance server (SA) storing time offsets of clocks of the base stations with respect to a reference clock (for example, the clock of a radio navigation satellite system CS). Said locating device (D) comprises processing means (MT) for collecting, in the case of location request from a mobile terminal (UE1), analysable signals which are received from at least two base stations (BTS1, BTS2, BTS3) and provided with a representative time stamping of a time interval selected with respect to the clock of the base stations thereof and representative data of time offsets of said base stations (BTS1, BTS2, BTS3), and to determine the position of the mobile terminal (UE1) by triangulation on the basis of the analysable signals and collected data.