Apparatuses and methods of securing Global Navigation Satellite Systems are disclosure. In one exemplary embodiment, a mobile device may comprise: a communication interface configured to monitor signals from a plurality of satellites, a processor configured to determine impairment of one or more satellites in the plurality of satellites using the signals form the plurality of satellites, a memory configured to store a status of the determined impairment of one or more satellites in the plurality of satellites, and the communication interface that transmits the status of the determined impairment of the one or more satellites in the plurality of satellites to a server. The processor further determines a position of the mobile device using the status of the determined impairment of one or more satellites in the plurality of satellites, and stores the determined position and a corresponding digital certificate indicative of authenticity of the determined position in a memory.

A correction generation unit 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 for each of the plurality of evaluation points, based on a carrier phase of a positioning signal observed at each of a plurality of electronic reference points. A reference calculation unit 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 for each of the plurality of evaluation points. A ranging error calculation unit removes a bias component due to ambiguity from a difference between the amount of evaluation point correction and the amount of reference correction and thereby calculates a ranging error at each of the plurality of evaluation points.

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.

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. A navigation signal transmitter is configured to broadcast the navigation message to at least one client device, the navigation message facilitating the at least one client device to determine an enhanced position of the at least one client device based on the navigation message.

A positioning device includes a first GNSS receiver; a communication link configured to receive a spatial position, code measurements and carrier phase measurements of a second GNSS receiver; an input interface to a processing logic, the processing logic being configured to: calculate a position of the first positioning device from communicated data; and to estimate one or more parameters representative of multipath at the position of the first positioning device; wherein the communication link is configured to communicate to a second positioning device the parameters representative of multipath at the position of the first positioning device. Described developments comprise the use of multipath severity indicators, the determination of relative distances between receivers, validity conditions in time and/or space of multipath, various embodiments in a train or in a group of vehicles. Software aspects are discussed.

A system and method are provided for delivering orbit and clock corrections for Global Navigation Satellite Systems (GNSS) having: (1) reduced orbit and clock discontinuities when changes in ephemeris message from a satellite occur; (2) reduced quantization error by quantifying quantization error by fitting data within the constraints of the output message to prevent broadcast of large errors; and (3) reduced potential errors caused by old but active data.

A system and method for determining a receiver position can include determining a receiver position based on a set of satellite observations, determining the receiver position based on sensor measurements, determining a satellite observation discontinuity; based on the satellite observation discontinuity, determining a second receiver position.

A system and method for determining a receiver position can include determining a receiver position based on a set of satellite observations, determining the receiver position based on sensor measurements, determining a satellite observation discontinuity; based on the satellite observation discontinuity, determining a second receiver position.

Apparatuses and methods of securing Global Navigation Satellite Systems are disclosure. In one exemplary embodiment, a mobile device may comprise: a communication interface configured to monitor signals from a plurality of satellites, a processor configured to determine impairment of one or more satellites in the plurality of satellites using the signals form the plurality of satellites, a memory configured to store a status of the determined impairment of one or more satellites in the plurality of satellites, and the communication interface that transmits the status of the determined impairment of the one or more satellites in the plurality of satellites to a server. The processor further determines a position of the mobile device using the status of the determined impairment of one or more satellites in the plurality of satellites, and stores the determined position and a corresponding digital certificate indicative of authenticity of the determined position in a memory.

The disclosed method for determining atmospheric time delays involves receiving at least two signals, where the signals each have a different carrier frequency. The method further involves amplifying each of the signals with a respective amplifier for each of the signals to produce amplified signals. Also, the method involves digitizing each of the amplified signals with a respective analog to digital converter (ADC) for each of the amplified signals to produce digital signals. In addition, the method involves correlating each of the digital signals with a code using a respective correlator for each of the digital signals to determine the time group delay differential between the signals. Further, the method involves calculating, with at least one processor, the time group delay coefficient of the signals by using the time group delay differential. The time group delay coefficient is used to correct for the atmospheric time delays in the signals.