Abstract: A method for the adaptive ascertainment of an integrity range of a parameter estimate, the integrity range describing the range within which an estimated parameter is located with a minimum probability. The method includes: a) Ascertaining basic integrity information with the aid of a base module of a modular system, b) ascertaining an item of first supplementary integrity information with the aid of a first supplementary module of the modular system if at least one precondition for the ascertaining of the item of first supplementary integrity information has been satisfied, c) ascertaining the integrity range using at least the item of basic integrity information or at least the basic integrity information and the item of first supplementary integrity information if the first item of supplementary integrity information was ascertained.

Abstract: A constellation configuration optimization method of a low earth orbit (LEO) satellite augmentation system for an ARAIM application includes: 1, traversing vertical protection levels after all subset solutions and fault modes under the condition that integrity risk and continuity risk are equally distributed, and determining the constraint conditions of LEO satellite constellation configuration parameters; 2, determining objective functions of LEO satellite constellation configuration parameters x1, x2, x3, x4, eliminating calculated values of abnormal vertical protection levels, and screening initial populations of the parameters x1, x2, x3, x4; 3, calculating fitness of the objective functions; 4, starting from a second generation population, merging a parent population with an offspring population to form a new offspring population; 5, performing local optimal selection on the new offspring population, screening out a maximum value of the objective functions as an optimal offspring, and repeating step 4 un

Abstract: A system for generating satellite positioning corrections includes a global correction module that generates a set of global pre-corrections based on modeling of global positioning error, a set of local correction modules that, for each local correction module of the set, takes input from a unique reference source and generates a set of local pre-corrections based on modeling of local positioning error; and a correction generator that generates a positioning correction from the set of global pre-corrections and the sets of local pre-corrections to correct a position of the mobile receiver.

Abstract: The disclosure relates to a method for satellite-based determination of a vehicle position, comprising the following steps: a) receiving GNSS satellite data; b) determining a vehicle's position with the GNSS satellite data received in step a); c) providing input variables that can have an effect on the accuracy of the vehicle position determined in step b); d) determining a positional accuracy of the vehicle position determined in step b) using an algorithm that assigns a positional accuracy to a vehicle position; and e) adapting the algorithm.

Abstract: A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites of a constellation of non-LEO navigation satellites in non-LEO around the earth. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites in a constellation of LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on applying precise point positioning (PPP) correction data to the first signaling, wherein the PPP correction data is received separately from the first signaling; and generating a navigation message based on the orbital position.

Abstract: A method for detecting the spoofing of a signal from a satellite in orbit. A receiver can be located on an aircraft to receive an apparent satellite signal. The method can include determining at least two characteristic signatures of the signal including a power level, and indicating the apparent satellite signal is a spoofed satellite signal.

Abstract: Improvements in Global Navigation Satellite System (GNSS) spoofing detection of a vehicle are disclosed utilizing bearing and/or range measurements acquired independently from GNSS technology. Bearing and/or range measurements are determined from a GNSS-calculated position. Additionally, bearing and/or range measurements are acquired from an independent sensor, such as a Very high frequency Omnidirectional Range (VOR) receiver and/or a Distance Measurement Equipment (DME) receiver. The differences between the GNSS-based bearing and/or range and the bearing and/or range determined from the independent sensor, along with any applicable sources of error or uncertainty (including the post-hoc residuals from the GNSS-calculated position), are input into an analytical algorithm (e.g., RAIM) to determine whether GNSS spoofing is present with respect to the calculated GNSS position.

Abstract: Systems and methods for integrity monitoring of primary and derived parameters are described herein. In certain embodiments, a method includes transforming an estimated error state covariance matrix of at least one primary integrity monitoring parameter of a navigation system onto an error state covariance matrix of one or more derived integrity monitoring parameters, wherein the one or more derived integrity monitoring parameters depends from the at least one primary integrity monitoring parameter. The method also includes transforming an integrity threshold of the at least one primary integrity monitoring parameter onto separation parameters of the one or more derived integrity monitoring parameters. The method further includes computing a protection limit for the one or more derived integrity monitoring parameters.

Abstract: A method and system for estimating a position of a mobile device is disclosed. In particular, a method and system in which the position of a mobile device is determined using measurements of received Global Navigation Satellite System, GNSS, satellite signals is disclosed. The present invention therefore proposes to qualify a received satellite signal based on whether a signal propagation characteristic of this signal falls within an expected range of this characteristic. The expected range is determined using information about the satellite that sent the signal. The position of the mobile device is computed based on the validated satellite signals.

Abstract: A computer implemented method for matching services to potential receivers of the services that includes registering at least one of service providers and service receivers as members to a service matching system. The service matching system collects data from the members. Permission to collect data from the members is revocable at any time by the members. The method further includes taking an order from a first service receiver to receive goods from a service provider; and calculating a route of the first service receiver to obtain the goods from the service provider. The method further includes matching the route of the first service receiver with a potential delivery route to a second service receiver having an order with the service provider; and offering a promotion to the first service receiver to deliver the order by the second service receiver with the service provider over the potential delivery route.

Abstract: In an example embodiment, a GNSS receiver may calculate protection levels for velocity and course over ground computed at a GNSS receiver. Specifically, the GNSS receiver may obtain Doppler measurements and variance measurements based on satellite signals received from at least five GNSS satellites. The GNSS receiver may utilize a least squares method to calculate the velocity states (e.g., x-velocity state, y-velocity state, and z-velocity state) and the clock bias for the GNSS receiver. The GNSS receiver may calculate the slope for each Doppler measurement on each velocity state. The GNSS receiver may then select the maximum slope for each velocity state and scale up the maximum slopes by a non-centrality parameter to calculate the protection level for each velocity state in the ECEF frame. The GNSS receiver may convert the velocity protection levels to NEU velocity protection levels to then calculate a protection level for course over ground.

Abstract: The present invention relates to a system for improving accuracy and safety of UAV navigation, and for generating an optimal protection level and geometry screening, and more particularly to a system that monitors an error and a failure of a GNSS navigation signal, broadcasts error correction information and integrity information to a UAV within a radius of about 20 km to allow the UAV to apply the corresponding information by a ground module, thereby improving the navigation accuracy and safety of the UAV. The ground module receives a GNSS navigation signal, calculates GNSS navigation error information, and generates correction information, and monitors a failure through a simplified failure monitoring algorithm, and the mounted module provides a system and a method for receiving a message that is broadcast by the ground module, and calculating precise and safe navigation information of an UAV by applying the message.

Abstract: A method for computing and applying alternative uncertainty limits is provided. The method includes generating a main solution from a plurality of received measurement signals. A solution separation is applied using a filter bank to generate sub-solutions from the received plurality of measurement signals. Each sub-solution uses all of the measurement signals from the plurality of measurement signals except one measurement signal to generate the associated sub-solution. Each sub-solution excludes a different measurement signal. One sub-solution is selected as fault free. A difference between the main solution and the selected sub-solution is determined. The determined difference is added to a rare normal protection limit to create a solution with improved integrity bounding. The solution with improved integrity bounding is then implemented.

Abstract: A method of supplementing a satellite based augmentation system approach during low visibility conditions is provided. The method includes acquiring satellite range measurements and additional measurements from at least one additional onboard independent sensor. Core sigma values are assigned for satellite range measurements and for each additional measurement from the at least one additional onboard independent sensor. A weighted position solution is determined using the acquired satellite range measurements, the acquired additional measurements and the assigned core sigma values. A discriminator is applied that utilizes vehicle positions derived from the acquired satellite range measurements and from the additional measurements to determine if a fault is present in the weighted position solution. An alert is generated if an output of the discriminator is outside a set tolerance value needed for low visibility operation.

Abstract: A system may include a global positioning system (GPS) receiver and inertial measurement units configured to generate signals representative of relative motion of the GPS receiver. The system may also include a navigation processor configured to receive a first position determination from the GPS receiver, and determine relative motion of the GPS receiver with respect to the first position determination based at least in part on signals received from the inertial measurement units. The navigation processor may also receive second respective distances between the GPS receiver and respective satellites based on signals received from the respective satellites, and determine second projected distances between the GPS receiver and the respective satellites based on the relative motion determination.

Abstract: A GBAS integrity risk allocation system based on key satellites is used to perform a GBAS integrity risk allocation method, including: reading data from an ephemeris at a certain time, and determining numbers of key satellites, key satellite pairs and key satellite groups at a certain time; under H2 hypothesis, allocating the integrity risks by using the fault probability of satellites in key satellite pairs or key satellite groups, where the integrity risks allocated by using the fault probability of satellites in key satellite pairs or key satellite groups include integrity risks caused by dual-receiver fault and integrity risks caused by ranging source fault; under H0 and H1 hypotheses, allocating the integrity risks by using the fault probability of non-key satellites; making an integrity allocation table according to the integrity risk allocation under the H0, H1 and H2 hypotheses.

Abstract: Provided are systems, methods, and computer-readable storage media for improving accuracy of GPS in luminaires. For example, in one embodiment, there is provided a method that includes receiving, at a controller coupled to a luminaire, a GPS message. The method further includes extracting information from the GPS message, the information including data associated with a plurality of coordinates. Furthermore, the method can include determining, based on the information and not from the coordinates, an error associated with each coordinate of the plurality of coordinates. The method can also include discarding coordinates for which the error fails to satisfy a predetermined condition. Moreover, the method can include selecting, as a location of the luminaire, the coordinates for which the error satisfies the predetermined condition.

Abstract: A Global Navigation Satellite System (GNSS) based navigation system with signal fault detection is provided. A least one controller is configured to; determine a true carrier phase measurement associated with each satellite signal received at each antenna of a plurality of spaced antennas; resolve integer ambiguities in true carrier phase measurement differences; and calculate at least one variable of a first navigation solution based on the obtained first set of resolved integer ambiguity measurements. The at least one controller is further configured to apply a solution separation process to repeatedly; calculate the at least one variable of a second navigation solution; determine a difference between the at least one variable of the second navigation solution and the first navigation solution; and detect a fault in satellite signals when the determined difference exceeds a defined threshold.

Abstract: A Global Navigation Satellite System (GNSS) based navigation system with signal fault detection is provided. A least one controller is configured to; determine a true carrier phase measurement associated with each satellite signal received at each antenna of a plurality of spaced antennas; resolve integer ambiguities in true carrier phase measurement differences; and calculate at least one variable of a first navigation solution based on the obtained first set of resolved integer ambiguity measurements. The at least one controller is further configured to apply a solution separation process to repeatedly; calculate the at least one variable of a second navigation solution; determine a difference between the at least one variable of the second navigation solution and the first navigation solution; and detect a fault in satellite signals when the determined difference exceeds a defined threshold.

Abstract: Disclosed are a system, apparatus, and method for monitoring integrity of satellites, and global navigation satellite systems (GNSS). One or more satellites in one or more GNSS are monitored based on a reference crowdsourced integrity report. One or more satellite integrity metrics are determined for the one or more satellites based at least on signals from the one or more satellites. A position of the mobile device is estimated. The position of the mobile device and the one or more satellite integrity metrics are provided.

Abstract: A system and method for monitoring and alerting of a working equipment proximity to a utility system. The invention provides a device on the working equipment with sensors and GPS location capabilities to determine location and/or movement event data of the equipment. The invention further includes the establishment of an imaginary buffer boundary established around the utility components to use in combination with the event data to provide a reference for alerts to be triggered. Alerts are automatically provided by the system and method at the working equipment and/or a remote operator dashboard.

Abstract: An integrity monitoring method for navigation systems with heterogeneous measurements is provided. Measurements from a plurality of different type navigation aiding sources are categorized by an information domain, an aiding class and an aiding section. The information domain is a category of at least one of estimated states and measurements that represent a same physical category. The aiding class is a category that uses a same physical method to acquire measurements. The aiding section is a category of measurements from the same aiding source. The measurements are organized into a plurality of measurement clusters based at least in part on measurement fault modes to be detected, measurement fault modes to be excluded, available computer resources and required performance. An integrity monitoring algorithm is applied to the measurement clusters to determine an integrity solution for all defined integrity monitoring classes.

Abstract: Methods for reducing the resources needed to detect and identify faulty pseudorange measurements in a GNSS receiver are described. In a Receiver Autonomous Integrity Monitoring (RAIM) method, a position solution is calculated using a weighted least squares method on measurements from satellites of one or more GNSS constellations. A test statistic is calculated from residuals and a threshold is calculated based on a probability function. If the test statistic is greater than or equal to the threshold, a subset is selected from the set of pseudorange measurements using a metric indicative of possible measurement error. A measurement is selected from the subset using a metric indicative of signal strength or some other metric and discarded from the set of pseudorange measurements. If the number of measurements remaining in the set of pseudorange measurements is greater than five, the method loops back to the step of calculating a position solution.

Abstract: A system and method provides an Automotive Safety Integrity Level (ASIL) qualifier for Global Navigation Satellite System (GNSS) position and related values. Specifically, hardware platform diagnostics are executed on one or more platforms associated with a GNSS Position Sensor (GNSSPS) that calculates/obtains position and/or related values. Also, a Receiver Autonomous Integrity Monitoring (RAIM) algorithm is executed on the calculated/obtained position and/or related values. If the results both produce a “good” qualifier, the position and/or related values is assigned an ASIL qualifier of “good” and may be utilized by an ASIL rated system. If either of the qualifiers is a “bad” qualifier, the position and/or related values is assigned an ASIL qualifier of “bad” and cannot be utilized by the ASIL rated system. In addition, the inventive system and method may compute a probability associated with an integrity violation of the RAIM algorithm which may consider the probability of hardware failure.

Abstract: A global navigation satellite system (GNSS) receiver including a processing device configured to: group GNSS satellites in view of the GNSS receiver into subsets based on relative geometries of the GNSS satellites relative to the GNSS receiver, wherein a GNSS satellite of the GNSS satellites is included in at most one subset of the subsets, wherein each subset of the subsets includes at least one GNSS satellite of the GNSS satellites and less than all GNSS satellites of the GNSS satellites, and wherein at least one subset includes more than one GNSS satellite; calculate a plurality of navigation sub-solutions based on data received at the GNSS receiver from the GNSS satellites using at least one GNSS antenna, wherein each navigation sub-solution of the navigation sub-solutions is calculated with at least one different subset of the subsets excluded; and calculate a protection level based on the navigation sub-solutions.

Abstract: Methods, systems, apparatus, and tangible non-transitory carrier media encoded with one or more computer programs that can determine the path or route most likely navigated by a mobile target are described. In accordance with particular embodiments, the most likely path or route is determined based on path-based scoring of position estimates obtained from different types of complementary locationing signal sources. Instead of fusing the position data derived from the different types of signal sources, these particular embodiments determine the most likely path navigated by the mobile target based on an independent aggregation of the position estimates derived from complementary signals of different source types.

Abstract: The present invention provides a ground-based augmentation system (GBAS) integrity performance evaluation method based on a pseudorange error distribution model, including: an airborne receiver terminal performing GBAS integrity performance evaluation by acquiring pseudorange error sample data, including the following method steps: a) grouping the pseudorange error sample data; b) building a distribution model having a Gaussian kernel and quadratic Gaussian polynomial tails for each group of pseudorange error samples; c) calculating a weighted sum of the distribution model of each group of pseudorange errors, to obtain an overall pseudorange error distribution model; d) projecting the pseudorange errors to position domain errors; e) calculating a probability that a position domain error is greater than an alarm limit, to obtain an integrity risk probability value; and f) evaluating GBAS integrity performance.

Abstract: The present disclosure provides an integrated navigation integrity monitoring system for unmanned aerial vehicles, comprising: an inertial measurement unit for providing a processor with zero offset values of different levels of inertial measurement units; a receiver for receiving signals from global satellite navigation and providing the processor with an integrity risk of a global satellite navigation system; and the processor for calculating a horizontal protection level of integrated navigation and a vertical protection level of integrated navigation, setting a horizontal alert limit and a vertical alert limit, comparing the horizontal protection level and the vertical protection level obtained by calculation with the corresponding horizontal alert limit and vertical alert limit respectively, and monitoring the integrity of the unmanned aerial vehicle. An inertial navigation system can be achieved without hardware redundancy, and the cost of integrated navigation integrity monitoring can be reduced.

Abstract: Embodiments of the invention provide that when performing a position fix a user who makes use of RTK or dGNSS correction data from a RTK/dGNSS service to obtain more accurate position fixes also receives from that same service data derived from the encrypted GNSS channels that authenticates whether the position fix determined by the mobile terminal based on the RTK/dGNSS data can be relied upon. By providing such an integrated service the mobile user terminal is able to obtain an authenticated, highly accurate positional fix which it can be certain can be relied upon.

Abstract: An efficient covariance matrix computation method is disclosed in connection with certain GNSS applications, including Advanced Receiver Autonomous Integrity Monitoring (ARAIM) and geometry screening. The system and method of the present application enable computation of multiple covariance matrices with substantially greater efficiency than previous approaches, including the rank-one update formula. For example, the system and method of the present application advantageously involves substantially fewer and simpler arithmetic operations than previous approaches. In addition, unlike the rank-one update formula, the system and method of the present application can be used to compute the subsolution in which all the satellites of a given constellation are removed.

Abstract: A method, GNSS simulator, and non-transitory computer readable medium for providing a simulated global navigation satellite system (GNSS) signal. The method includes receiving, by a GNSS simulator, a precision timing signal and one or more items of ephemeris data from a GNSS receiver based on a decoded GNSS signal received by the GNSS receiver. The precision timing signal and the one or more items of GNSS ephemeris data are received in a digital format over a communication network. A simulated GNSS signal is generated, by the GNSS simulator, based on the received precision timing signal and one or more items of ephemeris data. The simulated GNSS signal is transmitted, by the GNSS simulator, over a coverage area. A GNSS system for providing a simulated GNSS signal is also disclosed.

Abstract: An H-ARAIM system of optimizing a horizontal protection level includes constellations, a ground reference station and an aircraft, the ground reference station is used for receiving the satellite coordinate data of the constellations, and processing the received satellite coordinate data into an input data for the calculation of the aircraft horizontal protection level. The aircraft is built-in with a receiver and a data processor, the receiver is used for receiving the input data sent by the ground reference station, and transmitting the input data to the data processor for the data processing as follows: when a difference between a positioning solution of a full visible satellite and a positioning solution of a fault subset is within a threshold of a fault subset monitor system statistical magnitude, the receiver begins to calculate the protection level, which is calculated for protecting the iterative update.

Abstract: A method of advanced receiver autonomous integrity monitoring of a navigation system is discussed and two modifications facilitating its implementation in a hybrid navigation system are disclosed. In the first approach, relations describing the effect of unmodeled biases in pseudo-measurement on the Kalman filter state estimate are analytically derived and their incorporation into the integrity monitoring algorithm is described. The method comprises receiving a plurality of signals transmitted from space-based satellites, determining a position full-solution and sub-solutions, specifying a pseudorange bias, computing a transformation matrix for the full-solution and all sub-solutions using a Kalman filter, computing a bias effect on an error of filtered state vectors of all sub-solutions, and adding the effect to computed vertical and horizontal protection levels.

Abstract: Aspects of the disclosure relate to computing technologies. In particular, aspects of the disclosure relate to mobile computing device technologies, such as systems, methods, apparatuses, and computer-readable media for improving orientation data. In one embodiment, techniques are described for filtering data associated with a sensor coupled to a computing device, by receiving a signal from the sensor, detecting a change in a variability of a first signal parameter from a plurality of signal parameters from the signal, and adjusting, based at least in part on the detected change in the variability of the first signal parameter, at least one filter parameter of a filter used to filter a second signal parameter from the signal.

Abstract: Hybrid systems capable of performing both civilian and military GPS functions with hardware-enforced separation of data boundaries are disclosed. A hybrid system may include a first position data processor configured to generate a first set of position data based on signals received from a satellite navigation system and signals received from a digital antenna. The hybrid system may also include a second position data processor configured to generate a second set of position data based on signals received from the satellite navigation system and signals received from the digital antenna. The hybrid system may further provide a communication interface established between the first position data processor and the second position data processor.

Abstract: Embodiments for satellite subset selection for use in monitoring the integrity of computed navigation solutions are disclosed. In one embodiment, a Global Navigation Satellite System (GNSS) receiver comprises: a processing device configured to: group a plurality of satellites in view of the GNSS receiver into a plurality of subsets, wherein a satellite of the plurality of satellites is included in at most one subset of the plurality of subsets, wherein each subset of the plurality of subsets includes at least one satellite of the plurality of satellites and less than all satellites of the plurality of satellites, and wherein at least one subset includes more than one satellite; calculate a plurality of navigation sub-solutions, wherein each navigation sub-solution of the plurality of navigation sub-solutions is calculated with at least one different subset of the plurality of subsets excluded; and calculate a protection level.

Abstract: A method comprises receiving a plurality of signals from a plurality of space-based satellites, wherein the plurality of space-based satellites comprises at least one space-based satellite from each of a plurality of Navigation Satellite System (NSS) constellations. The method also comprises determining, in a first domain, a first plurality of sub-solutions based on a respective sub-set of the plurality of signals, each respective sub-set in the first domain chosen according to a characteristic defining the first domain; and determining, in a second domain, a second plurality of sub-solutions based on a respective sub-set of the plurality of signals, each respective sub-set in the second domain chosen according to a characteristic defining the second domain. The method further comprises determining if an error is present in the navigation system based on the first plurality of sub-solutions and on the second plurality of sub-solutions.

Abstract: A positioning management apparatus receives first reception information from a first mobile apparatus, the first reception information having been generated based on a received radio transmission from a transmitting apparatus, and receives second reception information from a second mobile apparatus, the second reception information having been generated based on a received radio transmission from a transmitting apparatus. The apparatus compares the first reception information with the second reception information, and, if the comparison indicates that both the first mobile apparatus and the second mobile apparatus received the radio transmission from the same transmitting apparatus, determines an association of the first mobile apparatus with the second mobile apparatus for use in positioning.

Abstract: The invention relates to a method for integrity monitoring of a primary set of measurements obtained from navigation signals sent by satellites and provided to an integrity control device comprising a plurality of Kalman filters, the method comprising the steps definition, for each Kalman filter, of a secondary set of measurements contained in the primary set, calculation by each Kalman filter of a navigation solution from a respective secondary set of measurements, wherein definition of the secondary sets respects the following principles: each measurement contained in the primary set is present in at least one of the secondary sets, for each p-uplet of measurements of the primary set, p being a predetermined integer greater than 1, at least one of the secondary sets does not contain said p-uplet of measurements, for each secondary set, at least one of the p-uplets is excluded from said secondary set, the method further comprising the steps of: detection, for each navigation solution, of at most p faulty mea

Abstract: The present invention relates to an apparatus and a method for identifying an anomalous satellite in a multi-reference station environment.

Abstract: Disclosed herein is a system for detecting manipulation of a GNSS signal and mitigating against such manipulation. A GNSS receiver receives GNSS signals from a plurality of GNSS satellites, and calculates event times for each GNSS satellite. The GNSS receiver then compares a next event time for a particular GNSS satellite with an expected next event time for the particular GNSS satellite. If the difference between the expected next event time and the next event times exceeds a predetermined threshold, then the GNSS receiver indicates that signal integrity may be compromised.

Abstract: A method of advanced receiver autonomous integrity monitoring of a navigation system is discussed and two modifications facilitating its implementation in a hybrid navigation system are disclosed. In the first approach, relations describing the effect of unmodeled biases in pseudo-measurement on the Kalman filter state estimate are analytically derived and their incorporation into the integrity monitoring algorithm is described. The method comprises receiving a plurality of signals transmitted from space-based satellites, determining a position full-solution and sub-solutions, specifying a pseudorange bias, computing a transformation matrix for the full-solution and all sub-solutions using a Kalman filter, computing a bias effect on an error of filtered state vectors of all sub-solutions, and adding the effect to computed vertical and horizontal protection levels.

Abstract: Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.

Abstract: A method for determining the integrity risk at an alert limit of a position solution determined with a satellite navigation system involves calculating a first integrity risk at the alert limit assuming that one satellite j of the satellites is faulty. A first position solution is determined with the signals from all of the satellites and a second position solution is determined with the signals from all of the satellites except for the signal received from the satellite j. A difference between the first and the second position solution is identified and subtracted from the alert limit to create a reduced alert limit. A second integrity risk at the reduced alert limit is calculated with the signals received from all satellites except the signal received from the satellite j. The integrity risk at the alert limit is determined using the minimum of the first and second integrity risks.

Abstract: Disclosed is a method for determining the position of a terminal. The method for determining the position of a terminal belonging to an overlay network environment comprises: a step in which the terminal transmits a position determination request to a positioning server; and a step in which the terminal receives, from the positioning server, position determination support information comprising a virtual cell ID allocated to transmission points surrounding the terminal. Therefore, using this method for determining the position of a terminal enables highly accurate position determination even in an overlay network environment in which a plurality of transmission points are configured so as to have the same cell ID.

Abstract: The present invention relates to a method for detecting and excluding at least one pseudo-range measured between a satellite and a receiver for receiving signals transmitted by different satellites of a radio-positioning constellation when said pseudo-range is faulty, characterized in that said method includes the steps of: (a) determining an estimation of the position of the receiver from the pseudo-ranges measured by the receiver, (b) estimating, from the thus-estimated position, biases in the measured pseudo-ranges; (c) processing the thus-obtained biases in order to derive a value representative of the probability of a fault for each pseudo-range; (d) preselecting, on the basis of the resulting values, a given number of pseudo-ranges which are most likely to be faulty; (e) determining, for each combination of pseudo-ranges from among the thus-preselected pseudo-ranges, a value of a test variable representative of the likelihood the combination is faulty; (f) selecting, on the basis of the values of the th

Abstract: Methods and integrated circuits for performing receiver autonomous integrity monitoring (RAIM) in global navigation satellite system (GNSS) receivers are disclosed. In an embodiment, a first information comprising current position related information is accessed. A second information comprising predicted position related information is accessed based on previously received information. A solution is computed based on the first information and the second information and a presence of outlier information is determined in at least one of the first information and the second information based on the solution.

Abstract: A method comprises receiving a plurality of signals from a plurality of space-based satellites, wherein the plurality of space-based satellites comprises at least one space-based satellite from each of a plurality of Navigation Satellite System (NSS) constellations. The method also comprises determining, in a first domain, a first plurality of sub-solutions based on a respective sub-set of the plurality of signals, each respective sub-set in the first domain chosen according to a characteristic defining the first domain; and determining, in a second domain, a second plurality of sub-solutions based on a respective sub-set of the plurality of signals, each respective sub-set in the second domain chosen according to a characteristic defining the second domain. The method further comprises determining if an error is present in the navigation system based on the first plurality of sub-solutions and on the second plurality of sub-solutions.

Abstract: A process for determination of navigation parameters of a carrier by a hybridisation device comprising a bank (3) of Kalman filters, each working out a hybrid navigation solution from inertial measurements calculated by a virtual platform (2) and raw measurements of signals emitted by a constellation of satellites supplied by a satellite-positioning system (GNSS), characterised in that it comprises the steps of: determination for each satellite of at least one probability ratio between a hypothetical breakdown of given type of the satellite and a hypothetical absence of breakdown of the satellite, declaration of a breakdown of given type on a satellite as a function of the probability ratio associated with this breakdown and of a threshold value, estimation of the impact of the breakdown declared on each hybrid navigation solution, and correction of hybrid navigation solutions as a function of the estimation of the impact of the breakdown declared.

Abstract: A navigation system includes first receiver receiving satellite signals, second receiver receiving differential correction data from ground receivers, and processing device coupled to receivers.