US-12618985-B2 - Cooperative positioning with multiple global navigation satellite system receivers

Abstract

Techniques are provided for integrating GNSS measurements between two or more GNSS receivers. An example method includes determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first GNSS receiver and a second antenna that is communicatively coupled to a second GNSS receiver, determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver at a first time, determining a second position estimate and a second IAR status with the second GNSS receiver at approximately the first time, computing a horizontal offset value based on the antenna baseline vector and a difference between the first position estimate and the second position estimate, and generating the wrong fix indication in response to the first IAR status being fixed, the second IAR status being fixed, and the horizontal offset value being greater than a threshold value.

Inventors

• Yuxiang PENG
• Min Wang
• Ning Luo

Assignees

• QUALCOMM INCORPORATED

Dates

Publication Date

20260505

Application Date

20230213

Claims (20)

1. 1 . A method for improving positioning accuracy convergence in two global navigation satellite system (GNSS) receivers, comprising: determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, wherein the antenna baseline vector is referenced from the first antenna to the second antenna; determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver, wherein the first IAR status is at least either a float status or a fixed status; and providing the first position estimate and the antenna baseline vector to the second GNSS receiver in response to the first IAR status being the fixed status.
2. 2 . The method of claim 1 wherein the first GNSS receiver is a smartphone and the second GNSS receiver is disposed in a vehicle with the second antenna being in a fixed location on the vehicle.
3. 3 . The method of claim 2 wherein the smartphone is disposed outside and proximate to the vehicle, and determining the antenna baseline vector includes performing a radio frequency ranging exchange between the smartphone and an on-board unit disposed in the vehicle.
4. 4 . The method of claim 3 wherein the radio frequency ranging exchange includes one or more ultrawideband (UWB) ranging messages.
5. 5 . The method of claim 3 wherein providing the first position estimate and the antenna baseline vector includes providing one or more sidelink messages including the first position estimate and the antenna baseline vector to the on-board unit.
6. 6 . The method of claim 2 wherein the smartphone is disposed within the vehicle, and determining the antenna baseline vector includes performing a radio frequency ranging exchange between the smartphone and an on-board unit disposed in the vehicle.
7. 7 . The method of claim 1 wherein determining the antenna baseline vector includes obtaining respective position estimates for the first GNSS receiver and the second GNSS receiver based on a precise point positioning (PPP) or real time kinematic (RTK) and correction signals received from a reference GNSS station.
8. 8 . An apparatus, comprising: a memory; at least one transceiver; at least one processor communicatively coupled to the memory and the at least one transceiver, and configured to: determine an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, wherein the antenna baseline vector is referenced from the first antenna to the second antenna; determine a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver, wherein the first IAR status is at least either a float status or a fixed status; and provide the first position estimate and the antenna baseline vector to the second GNSS receiver in response to the first IAR status being the fixed status.
9. 9 . The apparatus of claim 8 wherein the first GNSS receiver is a smartphone and the second GNSS receiver is disposed in a vehicle with the second antenna being in a fixed location on the vehicle.
10. 10 . The apparatus of claim 9 wherein the at least one processor is further configured to perform a radio frequency ranging exchange with the smartphone.
11. 11 . The apparatus of claim 10 wherein the radio frequency ranging exchange includes one or more ultrawideband (UWB) ranging messages.
12. 12 . The apparatus of claim 10 wherein the at least one processor is further configured to provide one or more sidelink messages including the first position estimate and the antenna baseline vector.
13. 13 . The apparatus of claim 8 wherein the at least one processor is further configured to obtain respective position estimates for the first GNSS receiver and the second GNSS receiver based on a precise point positioning (PPP) or real time kinematic (RTK) and correction signals received from a reference GNSS station.
14. 14 . An apparatus for improving positioning accuracy convergence in two global navigation satellite system (GNSS) receivers, comprising: means for determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, wherein the antenna baseline vector is referenced from the first antenna to the second antenna; means for determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver, wherein the first IAR status is at least either a float status or a fixed status; and means for providing the first position estimate and the antenna baseline vector to the second GNSS receiver in response to the first IAR status being the fixed status.
15. 15 . The apparatus of claim 14 wherein the first GNSS receiver is a smartphone and the second GNSS receiver is disposed in a vehicle with the second antenna being in a fixed location on the vehicle.
16. 16 . The apparatus of claim 15 wherein the means for determining the antenna baseline vector includes means for performing a radio frequency ranging exchange between the smartphone and an on-board unit disposed in the vehicle.
17. 17 . The apparatus of claim 16 wherein the radio frequency ranging exchange includes one or more ultrawideband (UWB) ranging messages.
18. 18 . The apparatus of claim 16 wherein the means for providing the first position estimate and the antenna baseline vector includes means for providing one or more sidelink messages including the first position estimate and the antenna baseline vector to the on-board unit.
19. 19 . The apparatus of claim 14 wherein the means for determining the antenna baseline vector includes means for obtaining respective position estimates for the first GNSS receiver and the second GNSS receiver based on a precise point positioning (PPP) or real time kinematic (RTK) and correction signals received from a reference GNSS station.
20. 20 . A non-transitory processor-readable storage medium comprising processor-readable instructions configured to cause one or more processors to improve positioning accuracy convergence in two global navigation satellite system (GNSS) receivers, comprising code for: determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, wherein the antenna baseline vector is referenced from the first antenna to the second antenna; determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver, wherein the first IAR status is at least either a float status or a fixed status; and providing the first position estimate and the antenna baseline vector to the second GNSS receiver in response to the first IAR status being the fixed status.

Description

FIELD The subject matter disclosed herein relates generally to satellite based positioning systems, and in particular, to systems and methods for integrating Global Navigation Satellite System (GNSS) receiver measurements between two or more GNSS receivers. BACKGROUND The Global Positioning System (GPS) is an example of a GNSS navigation system in which a receiver determines its position by precisely measuring the arrival time of signaling events received from multiple satellites. Each satellite transmits a navigation message containing the precise time when the message was transmitted and ephemeris information. GNSS accuracy may degrade significantly under weak signal conditions such as when the line-of-sight (LOS) to the satellite vehicles is obstructed by natural or manmade objects. In some cases, the weak signals may cause cycle slip and diminish the integer ambiguity resolution (IAR) in the GNSS receiver. Such errors may induce an absolute position error of the order of tens of meters (e.g. as much as 50 meters) and relative position error of the order several meters. In addition, accuracy may be further degraded by the limited availability of good GNSS measurements. For example, with GNSS measurements that use carrier phase to achieve higher accuracy, positioning accuracy is dependent on a constant lock. Techniques to quickly resolve IAR and repair cycle slip failures may improve the accuracy and robustness of GNSS receivers. SUMMARY An example method for generating a wrong fix indication based on measurements from multiple global navigation satellite system (GNSS) receivers according to the disclosure includes determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver at a first time, determining a second position estimate and a second IAR status with the second GNSS receiver at approximately the first time, computing a horizontal offset value based on the antenna baseline vector and a difference between the first position estimate and the second position estimate, and generating the wrong fix indication in response to the first IAR status being fixed, the second IAR status being fixed, and the horizontal offset value being greater than a threshold value. An example method for repairing a cycle slip error in a global navigation satellite system (GNSS) receiver according to the disclosure includes determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver at a first time, determining a second position estimate and a second IAR status with the second GNSS receiver at approximately the first time, determining a carrier phase value in the first GNSS receiver in response to the first IAR status being fixed and the second IAR status being float, and repairing the cycle slip error in the second GNSS receiver based at least in part on the carrier phase value and the antenna baseline vector. An example method for improving positioning accuracy convergence in two global navigation satellite system (GNSS) receivers according to the disclosure includes determining an antenna baseline vector based on relative locations of a first antenna that is communicatively coupled to a first global navigation satellite system (GNSS) receiver and a second antenna that is communicatively coupled to a second GNSS receiver, determining a first position estimate and a first integer ambiguity resolution (IAR) status with the first GNSS receiver, and providing the first position estimate and the antenna baseline vector to the second GNSS receiver in response to the first IAR status being fixed. Items and/or techniques described herein may provide one or more of the following capabilities, as well as other capabilities not mentioned. Two or more GNSS receivers may receive satellite signals and generate position estimates. An antenna baseline vector may be determined based on the relative geometry of the GNSS receiver antennas. GNSS measurement data obtained by the respective GNSS receivers may be integrated based at least in part on the antenna baseline vector. The resulting positioning performance may be enhanced such that the occurrence of IAR wrong fix errors may be reduced, and carrier phase cycle slip detection and repair may be improved. In some implementations, the time required for positioning accuracy convergence for GNSS measurements in the respective GNSS receivers may decrease, and the tim