Snap-to-Road Using Wireless Access Point Data

• US 20110077862A1
• Filed: 09/29/2009
• Published: 03/31/2011
• Est. Priority Date: 09/29/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Mayor, Robert, Huang, Ronald Keryuan
• Granted Patent: US 8,825,375 B2
• Time in Patent Office: Days
• US Class Current: 701/208
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Techniques for performing more accurate snap-to-road calculations using wireless access point data are disclosed. In one aspect, a corrected location corresponding to received location data is selected from a plurality of candidate map locations based on a correspondence between the access points visible to a device and the access points visible at the corrected map location. In another aspect, road vector data is augmented with access point data, and a corrected map location is selected based on a correspondence between the access points visible to the device, and the augmented road vector data.

Claims

1. A computer-implemented method, comprising:

receiving location data and device access point data for a device, the location data indicating an estimated location of the device and the device access point data identifying one or more wireless access points visible to the device;

identifying a plurality of candidate map locations corresponding to the estimated location, each candidate map location being on a road and associated with road access point data identifying one or more wireless access points visible at the candidate map location;

selecting a corrected map location from the plurality of candidate map locations, the selecting based at least in part on a respective correspondence between the device access point data and the road access point data for each candidate map location; and

resolving the estimated location to the corrected map location.

2. The method of claim 1, where the access point data further includes a signal strength for each wireless access point visible to the device, and the road data further includes a signal strength for each wireless access point visible at the candidate map location.

3. The method of claim 1, where selecting the corrected map location includes:

calculating a score for each candidate map location, the score based in part on the correspondence between the device access point data and the road access point data; and

selecting the corrected map location according to the scores for the candidate map locations.

4. The method of claim 3, where calculating the score includes determining a correspondence between the road access point data for each candidate map location and the device access point data.

5. The method of claim 3, where the score is a weighted score, and calculating the weighted score includes:

associating a probability with each candidate map location, the probability indicating a likelihood that the candidate map location is an accurate location of the device, the probability determined from the correspondence between the device access point data and the road access point data;

determining a location score for each candidate map location, the score corresponding to a correspondence between the location data and map data describing, for each candidate map location, a road that the candidate map location is on; and

weighting the location scores for the candidate map locations by the probability associated with each candidate map location.

6. The method of claim 1, where the location data is GPS data or cellular network data.

7. The method of claim 1, where the device is a mobile device.

8. The method of claim 1, where identifying a plurality of candidate map locations corresponding to the estimated location includes identifying candidate map locations on known roads, each candidate map location having an estimated error that is less than a threshold amount of error.

9. The method of claim 1, wherein resolving the estimated location to the corrected map location includes presenting the corrected map location as a current location of the device.

10. The method of claim 1, wherein resolving the estimated location to the corrected map location includes providing the corrected map location as a current location of the device to a process running on the device.

11. A computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations comprising:

receiving location data and device access point data for a device, the location data indicating an estimated location of the device and the device access point data identifying one or more wireless access points visible to the device;

identifying a plurality of candidate map locations corresponding to the estimated location, each candidate map location being on a road and associated with road access point data identifying one or more wireless access points visible at the candidate map location;

selecting a corrected map location from the plurality of candidate map locations, the selecting based at least in part on a respective correspondence between the device access point data and the road access point data for each candidate map location; and

resolving the estimated location to the corrected map location.

12. The computer-readable medium of claim 11, where the access point data further includes a signal strength for each wireless access point visible to the device, and the road data further includes a signal strength for each wireless access point visible at the candidate map location.

13. A system comprising:

a processor;

a display device;

one or more storage devices; and

a computer readable medium coupled to the processor and including instructions, which, when executed by the processor, causes the processor to perform operations comprising;

receiving location data and device access point data for a device, the location data indicating an estimated location of the device and the device access point data identifying one or more wireless access points visible to the device;

identifying a plurality of candidate map locations corresponding to the estimated location, each candidate map location being on a road and associated with road access point data identifying one or more wireless access points visible at the candidate map location;

selecting a corrected map location from the plurality of candidate map locations, the selecting based at least in part on a respective correspondence between the device access point data and the road access point data for each candidate map location; and

resolving the estimated location to the corrected map location.

14. The system of claim 13, where the access point data further includes a signal strength for each wireless access point visible to the device, and the road data further includes a signal strength for each wireless access point visible at the candidate map location.

15. A computer-implemented method, comprising:

receiving device access point data for a device, the device access point data identifying one or more wireless access points visible to the device;

correcting an estimated location of the device by selecting a corrected map location from a plurality of candidate map locations, the corrected map location having a best correspondence between wireless access points visible at the corrected map location and the device access point data.

16. The method of claim 15, wherein the device access point data further includes data identifying a signal strength of each visible wireless access point, and the corrected map location has a best correspondence between the access point data and wireless access points visible at the corrected map location and a signal strength of each wireless access point visible to the device.

17. A computer-implemented method, comprising:

receiving map data, the map data including data for a plurality of roads and road access point data for candidate map locations on each road, the road access point data identifying, for each candidate map location, wireless access points visible from the candidate map location;

receiving device access point data identifying one or more wireless access points visible to a device;

identifying a corrected map location on a road for the device based, at least in part, on a respective correspondence between the road access point data for candidate map locations on each road and the device access point data.

18. The method of claim 17, where the road access point data for a candidate map location includes a signal strength for each visible access point at the candidate map location and the device access point data includes a signal strength for each wireless access point visible to the device.

19. The method of claim 17, where the map data is road vector data.

20. The method of claim 17, where the device is a mobile device.

21. The method of claim 17, where identifying a corrected map location on a road includes selecting a location on a road based on a minimum error calculated from the access point data for the location on the road and the device access point data.