Granted Patent B2

US 12,699,188 · App. 18/537,212 · Granted Aug 4, 2026

Inventors: Philippe Brocard (San Francisco, CA); Damien Theureau (San Francisco, CA); Jan Bolting (San Francisco, CA); Isak Tjernberg (San Francisco, CA); Sébastien Carcanague (San Francisco, CA)

Assignee: Swift Navigation, Inc.

G01S19/074

Abstract

Claims (43)

1 . A method comprising:

receiving global navigation satellite signal (GNSS) corrections;

determining a corrections monitor probability distribution associated with a corrections monitor, wherein the corrections monitor probability distribution comprises probabilities of GNSS correction errors for the GNSS corrections;

for each integrity risk of a plurality of integrity risks:

determining an error detection threshold based on a probability of false alarm associated with the corrections monitor probability distribution;

determining a residual error magnitude of a GNSS correction error of the GNSS corrections errors, that misses detection given the error detection threshold and the respective integrity risk; and

fitting the residual error magnitudes with a bound function, wherein every value of the bound function is greater than or equal to the residual error magnitudes for each integrity risk of the plurality of integrity risks;

based on the bound function and the GNSS corrections, determining a GNSS receiver position of a GNSS receiver; and

reorienting the GNSS receiver based on the determined GNSS receiver position.

2 . The method of claim 1 , further comprising at the corrections monitor, generating a flag indicating whether GNSS corrections errors exceed the bound function.

3 . The method of claim 2 , wherein generating the flag comprises:

determining a residual over time between satellite observations received from a set of reference stations; and

comparing the residual over time to a monitoring threshold; wherein the flag indicates that the GNSS corrections do not exceed the bound function when the residual over time is less than or equal to the monitoring threshold and wherein the flag indicates that the GNSS corrections exceed the bound function when the residual over time is greater than the monitoring threshold.

4 . The method of claim 1 , further comprising determining a minimum residual error magnitude relative to a 10 −2 /hr percentile of the corrections monitor probability distribution.

5 . The method of claim 1 , wherein the bound function is a linear function of the form (residual error magnitudes)≤μ+Kσ, where K is a constant that depends on a target integrity risk.

6 . The method of claim 5 , wherein μ and σ are transmitted to a positioning engine, wherein the method further comprises at the positioning engine:

determining a bound associated with the GNSS corrections based on a target integrity risk associated with the positioning engine;

determining a positioning solution of a GNSS receiver based on satellite observations tracked by the GNSS receiver; and

comparing the positioning solution to the bound to determine whether the positioning solution meets a threshold probability for being safe to use.

7 . The method of claim 6 , wherein determining the positioning solution comprises:

correcting the satellite observations tracked by the GNSS receiver using the GNSS corrections; and

determining integer-valued carrier phase ambiguities for carrier phases of the satellite observations tracked by the GNSS receiver, wherein the positioning solution is determined based on the integer-valued carrier phase ambiguities.

8 . The method of claim 5 , wherein K is constrained to between 3.89 and 5.74.

9 . The method of claim 1 , wherein determining the corrections monitor probability distribution comprises:

predicting which satellites will be in-view of a reference station providing satellites observations to the corrections monitor; and

determining the corrections monitor probability distribution based on the predicted satellites and a set of feared events.

10 . The method of claim 1 , wherein the GNSS corrections and the bound function are determined by a corrections generator, wherein the corrections generator operates on a separate processor from the corrections monitor.

11 . The method of claim 1 , wherein the GNSS corrections comprise state space representation corrections for satellite clock errors, satellite code bias, satellite carrier bias, satellite orbit errors, and atmospheric delays.

12 . A system for determining GNSS corrections and bounds associated therewith comprising:

a corrections generator communicatively coupled to a set of reference stations and an integrity monitor, wherein the corrections generator is configured to:

receive a set of satellite observations from the set of reference stations;

determine the GNSS corrections based on the set of satellite observations from the set of reference stations;

determine the bounds associated with the GNSS corrections; and

the integrity monitor, wherein the integrity monitor is configured to determine whether a probability that the GNSS corrections exceed the bounds is greater than an allocated integrity risk, wherein the allocated integrity risk is a predetermined probability for the GNSS corrections to exceed the bounds;

wherein the corrections generator is configured to determine the bounds based on a predicted monitoring performance of the integrity monitor for determining whether the GNSS corrections exceed the bounds, wherein a GNSS receiver position is determined based on the GNSS corrections and the bounds, and where in the GNSS receiver is reoriented based on the GNSS receiver position.

13 . The system of claim 12 , further comprising a positioning engine communicatively coupled to the corrections generator configured to determine a position of a GNSS receiver by processing a set of satellite observations measured by the GNSS receiver and corrected using the GNSS corrections determined by the corrections generator.

14 . The system of claim 13 , wherein processing the set of satellite observations measured by the GNSS receiver comprises determining integer-valued carrier phase ambiguities for the set of satellite observations measured by the GNSS receiver.

15 . The system of claim 13 , wherein the corrections generator and the integrity monitor are implemented on a cloud processor remote from the GNSS receiver and wherein the positioning engine is implemented on a processor collocated with the GNSS receiver.

16 . The system of claim 12 , wherein the GNSS corrections comprise state space representation corrections for satellite clock errors, satellite code bias, satellite carrier bias, satellite orbit errors, and atmospheric delays.

17 . The system of claim 12 , wherein the bound is determined as a linear function according to bound≤μ+Kσ, where K is a constant that depends on a target integrity risk.

18 . The system of claim 17 , wherein K is constrained to between 3.89 and 5.74.

19 . The system of claim 12 , wherein the corrections generator is configured to determine the GNSS corrections using a Gaussian process, wherein the Gaussian process operates on the set of satellite observations measured by the set of reference stations independently without combining satellite observations.

20 . The system of claim 12 , wherein the corrections generator is configured to generate a minimum bound based on a 10 −2 /hr percentile of an integrity monitor probability distribution received from the integrity monitor.

Assignments (1)

Continuity (2)

References Cited (64)