US-12618982-B2 - Error characterization for GNSS-based position estimates on constrained routes

Abstract

One or more processors obtain GNSS receiver data captured during a time period by a GNSS receiver disposed onboard a constrained vehicle traversing a constrained route. The processor(s) determine a GNSS-based position estimate based on the GNSS receiver data. The position estimate indicates an estimated location of the GNSS receiver during at least a portion of the time period. The processor(s) determine an error characterization corresponding to an offset between the position estimate and an expected location of the GNSS receiver along the constrained route. The processor(s) cause a mobile device to perform a positioning or navigation-related function that accounts for the error characterization.

Inventors

• Saara KUISMANEN

Assignees

• HERE GLOBAL B.V.

Dates

Publication Date

20260505

Application Date

20220810

Claims (16)

1. 1 . A computer-implemented method comprising: capturing GNSS receiver data during a time period by a GNSS receiver disposed onboard a constrained vehicle, wherein the constrained vehicle is configured to traverse a constrained route; determining, by one or more processors, a GNSS-based position estimate indicating an estimated location of the GNSS receiver during at least a portion of the time period, the GNSS-based position estimate determined based at least in part on the GNSS receiver data; determining, by the one or more processors, an error characterization corresponding to an offset between the position estimate and an expected location of the GNSS receiver along the constrained route; causing, by one or more processors, a mobile device to perform a positioning or navigation-related function that accounts for the error characterization, wherein the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises a multi-dimensional displacement between the position estimate and the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period, and wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined based at least in part on at least one of (a) an inertial measurement unit (IMU) or (b) observations captured by a radio interface coupled to the constrained vehicle; and further wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined indirectly via a trusted server.
2. 2 . The method of claim 1 , wherein the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises the position estimate from the constrained route.
3. 3 . The method of claim 1 , wherein the error characterization comprises an error estimate for each GNSS satellite observed by the GNSS receiver.
4. 4 . The method of claim 1 , wherein causing the mobile device to perform a positioning or navigation-related function that accounts for the error characterization comprises at least one of (a) broadcasting the error characterization, (b) providing the error characterization in response to a received request, or (c) incorporating or causing the incorporating of the error characterization into a digital map or geographic database.
5. 5 . The method of claim 1 , wherein the mobile device performs the positioning or navigation-related function that accounts for the error characterization by at least one of (a) correcting a GNSS-based mobile device position estimate based on the error characterization, (b) correcting one or more observed GNSS signals based on the error characterization, or (c) determining a position of the mobile device using a non-GNSS-based positioning technique.
6. 6 . The method of claim 1 , wherein the error characterization comprises at least one of a velocity error estimate or a heading error estimate.
7. 7 . The method of claim 1 , wherein the constrained route is constrained by one of (a) rails along which the constrained vehicle travels or (b) dedicated travel lanes along which the constrained vehicle travels.
8. 8 . The method of claim 1 , wherein ground truth positions of one or more points along the constrained route are known and the error characterization is determined based at least in part on at least one of the ground truth positions.
9. 9 . An apparatus comprising at least one processor and at least one non-transitory memory including computer program code instructions, the computer program code instructions configured to, when executed, cause the apparatus to at least: capture GNSS receiver data during a time period by a GNSS receiver disposed onboard a constrained vehicle, wherein the constrained vehicle is configured to traverse a constrained route; determine, by one or more processors, a GNSS-based position estimate indicating an estimated location of the GNSS receiver during at least a portion of the time period, the GNSS-based position estimate determined based at least in part on the GNSS receiver data; determine, by the one or more processors, an error characterization corresponding to an offset between the position estimate and an expected location of the GNSS receiver along the constrained route; cause, by one or more processors, a mobile device to perform a positioning or navigation-related function that accounts for the error characterization, wherein the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises a multi-dimensional displacement between the position estimate and the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period, and wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined based at least in part on at least one of (a) an inertial measurement unit (IMU) or (b) observations captured by a radio interface coupled to the constrained vehicle; and further wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined indirectly via a trusted server.
10. 10 . The apparatus of claim 9 , wherein the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises the position estimate from the constrained route.
11. 11 . The apparatus of claim 9 , wherein the error characterization comprises an error estimate for each GNSS satellite observed by the GNSS receiver.
12. 12 . The apparatus of claim 9 , wherein causing the mobile device to perform a positioning or navigation-related function that accounts for the error characterization comprises at least one of (a) broadcasting the error characterization, (b) providing the error characterization in response to a received request, or (c) incorporating or causing the incorporating of the error characterization into a digital map or geographic database.
13. 13 . The apparatus of claim 9 , wherein the mobile device performs the positioning or navigation-related function that accounts for the error characterization by at least one of (a) correcting a GNSS-based mobile device position estimate based on the error characterization, (b) correcting one or more observed GNSS signals based on the error characterization, or (c) determining a position of the mobile device using a non-GNSS-based positioning technique.
14. 14 . The apparatus of claim 9 , wherein the error characterization comprises at least one of a velocity error estimate or a heading error estimate.
15. 15 . The apparatus of claim 9 , wherein the constrained route is constrained by one of (a) rails along which the constrained vehicle travels or (b) dedicated travel lanes along which the constrained vehicle travels.
16. 16 . A computer program product comprising at least one non-transitory computer-readable storage medium having computer-executable program code instructions stored therein, the computer-executable program code instructions comprising program code instructions to: capture GNSS receiver data during a time period by a GNSS receiver disposed onboard a constrained vehicle, wherein the constrained vehicle is configured to traverse a constrained route; determine, by one or more processors, a GNSS-based position estimate indicating an estimated location of the GNSS receiver during at least a portion of the time period, the GNSS-based position estimate determined based at least in part on the GNSS receiver data; determine, by the one or more processors, an error characterization corresponding to an offset between the position estimate and an expected location of the GNSS receiver along the constrained route; cause, by one or more processors, a mobile device to perform a positioning or navigation-related function that accounts for the error characterization, wherein the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises a multi-dimensional displacement between the position estimate and the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period, and wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined based at least in part on at least one of (a) an inertial measurement unit (IMU) or (b) observations captured by a radio interface coupled to the constrained vehicle; and further wherein the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined indirectly via a trusted server.

Description

TECHNOLOGICAL FIELD An example embodiment relates generally to positioning error characterization. In particular, an example embodiment generally relates to a positioning error characterization of position estimates corresponding to a location of a constrained vehicle on a constrained route. BACKGROUND Global Navigation Satellite Systems (GNSS) are generally directed to positioning and navigation solutions. It is estimated that the total number of GNSS receivers in the market exceeded 6 billion units by the end of 2018, and a GNSS receiver can be found in nearly every smartphone, smartwatch, new car, high-end drone, etc. The volume of GNSS receivers in apparatuses is still rapidly growing due to the GNSS integration into the Internet of Things (IoT) devices. However, in various scenarios, the position accuracy may be only 5-10 meters. BRIEF SUMMARY Various embodiments provide methods, apparatuses, systems, computer program products, and/or the like for determining and providing positioning error characterization and/or using positioning error characterization to perform one or more navigation-related functions that account for the error characterization. In various embodiments, GNSS receiver data is used to determine a position estimate that estimates the location of a constrained vehicle (e.g., a vehicle configured to traverse a constrained route) and to determine an error characterization of the positioning estimate based at least in part on the constrained vehicle being located on the constrained route. In an example embodiment, the error characterization comprises an offset (e.g., a scalar or vector description of the distance) between the position estimate estimating the location of the constrained vehicle and an expected location of the GNSS receiver onboard the constrained vehicle on the constrained route. The error characterization may then be used to cause a mobile device to perform a positioning or navigation-related function that accounts for the error characterization. According to an aspect of the present disclosure, a method is provided for performing error characterization aware navigation. The method comprises obtaining, by one or more processors (e.g., of a constrained apparatus, a network apparatus, and/or a mobile apparatus), GNSS receiver data captured during a time period. The GNSS receiver is disposed onboard a constrained vehicle that is configured to traverse a constrained route. The method further comprises determining, by the one or more processors a GNSS-based position, an estimated location of the GNSS receiver during at least a portion of the time period based at least in part on the GNSS receiver data. The method further comprises determining, by the one or more processors, an error characterization corresponding to an offset between the position estimate and an expected location of the GNSS receiver along the constrained route. The method further comprises causing, by the one or more processors, a mobile device to perform a positioning or navigation-related function that accounts for the error characterization. In an example embodiment, the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises the expected location from the constrained route. In an example embodiment, the error characterization comprising the offset between the position estimate and the expected location of the GNSS receiver further comprises a multi-dimensional displacement between the position estimate and the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period. In an example embodiment, the expected location of the GNSS receiver disposed aboard the constrained vehicle along the constrained route during the time period is determined based at least in part on at least one of (a) an Inertial Measurement Unit (IMU) or (b) observations captured by a radio interface coupled to the constrained vehicle. In an example embodiment, the error characterization comprises an error estimate for each GNSS satellite observed by the GNSS receiver. In an example embodiment, the mobile device performs a positioning or navigation-related function that accounts for the error characterization comprises at least one of (a) broadcasting the error characterization, (b) providing the error characterization in response to a received request, or (c) incorporating or causing the incorporating of the error characterization into a digital map or geographic database. In an example embodiment, the mobile device performs the positioning or navigation-related function that accounts for the error characterization by at least one of (a) correcting a GNSS-based mobile device position estimate based on the error characterization, (b) correcting one or more observed GNSS signals based on the error characterization, or (c) determining a position of the mobile device using a non-GNSS-based