Fast GPS recovery using map vector data

Patent metadata

Field	Value
Publication number	US-9798011-B2
Application number	US-201314015976-A
Country	US
Kind code	B2
Filing date	Aug 30, 2013
Priority date	Aug 31, 2012
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

Methods and apparatuses to assist a global positioning system (GPS) module to determine GPS position estimates for a wireless communication device is disclosed. Processing circuitry in the wireless communication device determines a potential or an actual inaccuracy in a GPS position estimate obtained from a GPS module. The processing circuitry obtains a set of map vector data stored in or associated with the wireless communication device. The processing circuitry determines a location estimate of the wireless communication device based on at least a portion of the set of map vector data. The processing circuitry provides the location estimate to the GPS module and obtains an updated GPS position estimate from the GPS module, the updated GPS position estimate based at least in part on the location estimate provided to the GPS module.

First claim

What is claimed is:

1. A method to assist a global positioning system (GPS) module to determine GPS position estimates for a wireless communication device, the method comprising:
determining a potential or an actual inaccuracy in a GPS position estimate obtained from the GPS module;
obtaining a set of map vector data stored in or associated with the wireless communication device, the set of map vector data comprising information for structures that contribute to interfering with direct line-of-sight reception of GPS satellite signals and to causing indirect reflected reception of GPS satellite signals;
determining a location estimate and an associated confidence measure from a plurality of location estimates for the wireless communication device, the plurality of location estimates having associated confidence measures, based on at least a portion of the set of map vector data that includes information for structures in an area near the GPS position estimate for the wireless communication device;
providing the location estimate and the associated confidence measure to the GPS module; and
obtaining an updated GPS position estimate from the GPS module, the updated GPS position estimate based at least in part on the location estimate and the associated confidence measure provided to the GPS module.

2. The method recited in claim 1 , further comprising:
obtaining a set of sensor data to supplement the set of map vector data; and
determining the location estimate and the associated confidence measure from the plurality of location estimates for the wireless communication device further based on at least a portion of the set of sensor data and at least the portion of the set of map vector data.

3. The method recited in claim 1 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting a loss of GPS satellite signals.

4. The method recited in claim 3 , further comprising:
detecting a recovery of at least one GPS satellite signal,
wherein providing the location estimate and the associated confidence measure to the GPS module occurs after detecting the recovery of the at least one GPS satellite signal.

5. The method recited in claim 1 , wherein the set of map vector data includes an exit position for a structural object that obstructs GPS satellite signals.

6. The method recited in claim 1 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting less than four independent GPS satellite signals.

7. The method recited in claim 1 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting a particular GPS position estimate obtained from the GPS module does not match within a threshold a triangulated position estimate obtained using signals from cellular radio towers or from wireless local area network access points.

8. The method recited in claim 1 , wherein determining the location estimate of the wireless communication device and the associated confidence measure comprises selecting a particular exit location from a plurality of exit locations associated with a structural object that obstructs GPS satellite signals, wherein the set of map vector data further comprises the structural object that obstructs GPS satellite signals and the plurality of exit locations.

9. A wireless communication device, comprising:
a global positioning system (GPS) module configured to receive global navigation satellite system (GNSS) signals and to determine a GPS position of the wireless communication device based at least in part on received GNSS signals; and
processing circuitry coupled to the GPS module, the processing circuitry comprising a processor and a memory storing instructions that, when executed by the processor, cause the wireless communication device to determine GPS position estimates by at least:
determining a potential or an actual inaccuracy in a GPS position estimate obtained from the GPS module;
obtaining a set of map vector data stored in or associated with the wireless communication device, the set of map vector data comprising information for structures that contribute to interfering with direct line-of-sight reception of GPS satellite signals and to causing indirect reflected reception of GPS satellite signals;
determining a location estimate and an associated confidence measure from a plurality of location estimates for the wireless communication device, the plurality of location estimates having associated confidence measures, based on at least a portion of the set of map vector data that includes information for structures in an area near the GPS position estimate for the wireless communication device;
providing the location estimate and the associated confidence measure to the GPS module; and
obtaining an updated GPS position estimate from the GPS module, the updated GPS position estimate based at least in part on the location estimate and the associated confidence measure provided to the GPS module.

10. The wireless communication device of claim 9 , wherein execution of the instructions further causes the wireless communication device to determine GPS position estimates by at least:
obtaining a set of sensor data to supplement the set of map vector data; and
determining the location estimate and the associated confidence measure from the plurality of location estimates for the wireless communication device further based on at least a portion of the set of sensor data and at least the portion of the set of map vector data.

11. The wireless communication device of claim 9 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting a loss of GPS satellite signals.

12. The wireless communication device of claim 11 , wherein execution of the instructions further causes the wireless communication device to determine GPS position estimates by at least:
detecting a recovery of at least one GPS satellite signal,
wherein providing the location estimate and the associated confidence measure to the GPS module occurs after detecting the recovery of the at least one GPS satellite signal.

13. The wireless communication device of claim 9 , wherein the set of map vector data includes an exit position for a structural object that obstructs GPS satellite signals, wherein the set of map vector data includes the structural object that obstructs GPS satellite signals.

14. The wireless communication device of claim 9 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting less than four independent GPS satellite signals.

15. The wireless communication device of claim 9 , wherein determining the potential or the actual inaccuracy in the GPS position estimate comprises detecting a particular GPS position estimate obtained from the GPS module does not match within a threshold a triangulated position estimate obtained using signals from cellular radio towers or from wireless local area network access points.

16. The wireless communication device of claim 9 , wherein determining the location estimate of the wireless communication device and the associated confidence measure comprises selecting a particular exit location from a plurality of exit locations associated with a structural object that obstructs GPS satellite signals, wherein the set of map vector data further comprises the structural object that obstructs GPS satellite signals and the plurality of exit locations.

17. A non-transitory computer-readable storage medium storing ins

Assignees

• Apple Inc

Inventors

• Macgougan Glenn D
• Mayor Robert W
• Rhee Stephen J

Classifications

• G01S19/40

  Correcting position, velocity or attitude · CPC title

• G01S19/26

  involving a sensor measurement for aiding acquisition or tracking · CPC title

• G01S19/24

  Acquisition or tracking {or demodulation} of signals transmitted by the system {(synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073)} · CPC title

• G01S19/06

  employing an initial estimate of the location of the receiver as aiding data or in generating aiding data · CPC title

• G01S19/07 Primary

  providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections · CPC title