A method for monitoring an integrity of reference stations, having known and fixed coordinates, of a correction service system for a satellite-supported navigation system. A first group of the reference stations is operated to receive satellite signals of a plurality of satellites of the satellite-supported navigation system. It is provided that a) a first reference station is selected from the first group, and b) at least one first correction value is ascertained as a function of the satellite signals respectively received by the remaining reference stations of the first group, and c) the monitoring of the integrity is carried out in that first coordinates of the first reference station, determined using the satellite signals received by the first reference station and using the at least one first correction value, are compared with the known coordinates of the first reference station and checked for at least one first deviation.

Systems and methods for sharing convergence data between GNSS receivers are disclosed. Convergence data received at a GNSS receiver via a communication connection may be utilized to determine a position of the GNSS receiver.

Systems and methods for monitoring excessive delay gradients using long reference receiver separation distances are provided. In one embodiment, a ground-based system comprising a plurality of reference receivers configured to receive satellite signals. The ground-based system further comprises a processor coupled to a memory. The processor is configured to determine whether the line of sight of a newly available satellite is within a gradient. The processor is further configured to determine a monitor measurement using accumulated carrier data for each pair of reference receivers of a plurality of reference receiver pairs. The processor is further configured to combine monitor measurements for a subset of the plurality of reference receiver pairs into a monitor discriminator. The processor is further configured to output an alert when the monitor discriminator exceeds a threshold.

Systems and methods for using multi frequency satellite measurements to mitigate spatial decorrelation errors caused by ionosphere delays are provided. In one embodiment, a GBAS comprises: a plurality of GNSS reference receivers that receive signals from GNSS satellites; at least one processing module; at least one aircraft communication device; wherein the processing module determines a TEC along a line of sight of a first observable multi-frequency GNSS satellite to determine a current quality metric of the ionosphere; determines at least one overbounded Vertical Ionosphere Gradient standard deviation sigma-vig (.sub.vig) when the current quality metric of the ionosphere meets a threshold; defines one or more valid iono regions at a given finite period in time where at least one .sub.vig is applicable; and causes the communication device to communicate to an aircraft the .sub.vig and a list of GNSS single and multi-frequency satellites having pierce points in the valid iono regions.

System and method for a Ground Based Augmentation System (GBAS) for detecting ionospheric and tropospheric disturbances using Multi Frequency Monitor. Receiving signals from a plurality of receiver pairs and determining a monitor measurement of tropospheric delay variation using data from at least one pair of the plurality of receivers. Determining a monitor measurement of the sum of tropospheric and the sum of ionospheric delay variations using data from the at least one pair of the plurality of receivers. Combining monitor measurements of tropospheric delay variations and of ionospheric delay variations into an ionospheric delay estimate.

A low-earth orbit (LEO) satellite operates to: determine an orbital position of the LEO satellite based on the first signaling and based on precise point positioning (PPP) correction data associated with the constellation of non-LEO navigation satellites, wherein the PPP correction data includes orbital correction data and timing correction data associated with the constellation of non-LEO navigation satellites, and wherein the PPP correction data is received separate from the first signaling; determine, based on the inter-satellite communications, an error condition associated with one of the other LEO navigation satellites of the constellation of LEO navigation satellites; and broadcast a navigation message based on the orbital position, wherein the navigation message includes a timing signal and the orbital position associated with the LEO satellite, correction data associated with the constellation of non-LEO navigation satellites, and an alert signal that indicates the error condition associated with one of the other LEO navigation satellites of the constellation of LEO navigation satellites.

The present application provides a method for navigation and positioning of a receiver, including: receiving basic broadcast messages and correction parameters of a plurality of satellites, and establishing a pseudorange observation equation and a carrier-phase observation equation corresponding to each of satellites respectively; correcting the pseudorange observation equation and the carrier-phase observation equation using the received correction parameters to obtain the corrected pseudorange observation equation and the corrected carrier-phase observation equation; constructing a first observation according to the corrected pseudorange observation equation and the corrected carrier-phase observation equation; constructing a second observation according to the corrected pseudorange observation equation and the corrected carrier-phase observation equation; and jointly solving the obtained first observations and second observations of the plurality of satellites to obtain anoperation result of user positioning.

A correction generation unit (110) generates an amount of correction for a phase pseudorange between a positioning satellite and each of a plurality of evaluation points, as an amount of evaluation point correction (111) for each of the plurality of evaluation points, based on a carrier phase of a positioning signal (211) observed at each of a plurality of electronic reference points. A reference calculation unit (120) calculates a difference between the phase pseudorange between the positioning satellite and each of the plurality of evaluation points and a geometric distance between the positioning satellite and each of the plurality of evaluation points, as an amount of reference correction (121) for each of the plurality of evaluation points. A ranging error calculation unit (130) removes a bias component due to ambiguity from a difference between the amount of evaluation point correction (111) and the amount of reference correction (121) and thereby calculates a ranging error (131) at each of the plurality of evaluation points.

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 method for providing integrity information for checking atmospheric correction parameters for the correction of atmospheric disturbances for satellite navigation for a vehicle includes reading state signals relating to a state of an atmosphere between at least one satellite receiver and at least one satellite of the at least one satellite receiver. Each state signal represents certain state data that are transmitted between a satellite and a satellite receiver. The method further includes using at least one satellite signal and that are dependent on a state of the atmosphere between the satellite and the satellite receiver. The method further includes determining the integrity information using the state data. A variation of the state data against time is analyzed.