Determining location via wireless access points

• US 9,693,194 B2
• Filed: 03/22/2016
• Issued: 06/27/2017
• Est. Priority Date: 09/14/2015
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Pandey, Santosh, Peng, Rong
• Primary Examiner(s): MIZRAHI, DIANE D
• Application Number:
  US15/077,875
• Publication Number:
  US 20170078843A1
• Time in Patent Office: 462 Days
• Field of Search: None
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G01S 5/0054 of actual mobile position, i.e. position calculation on base station
• CPC Class Codes: G01S 5/0268 by deriving positions from different combinations of signals or of estimated positions in a single positioning system
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence
• CPC Class Codes: G01S 5/04 Position of source determined by a plurality of spaced direction-finders
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Determining a location of a user device comprises a wireless computing system supported by an access point. The wireless computing system receives a signal from the user device. The system estimates a location of the user device based on RSSI and calculates a boundary around the estimated location. The wireless computing system selects a plurality of sections inside of the boundary and performs a coarse calculation of a location of the user device based on an angle of arrival of the received signal. The system determines sections of the plurality of sections that have results from the coarse calculation that are more likely to be a location of the user device. The system performs a fine calculation of the location based on the angle of arrival of the received signal within each of the sections. The system identifies a particular section as the location of the user device.

Claims

1. A method, comprising:

receiving, by at least one wireless computing system access point logically connected to a wireless computing system, a wireless signal from a user computing device;

calculating, by the wireless computing system, a location estimate of the user computing device relative to the at least one wireless computing system access point and based on a signal strength of the received wireless signal;

calculating, by the wireless computing system, a boundary encompassing the estimated location of the user computing device;

dividing, by the wireless computing system, an area inside the boundary into a plurality of sections;

computing, by the wireless computing system, a first calculation of a location of the user computing device within the boundary based on an angle of arrival of the signal received by the at least one wireless computing system access point;

determining, by the wireless computing system, a likelihood for each of the plurality of sections of being an actual location of the user computing device based on the computed first calculation of a location;

ranking, by the wireless computing system, the sections based on the likelihoods for each of the plurality of sections of being an actual location of the user computing device;

identifying, by the wireless computing system, one or more sections of the plurality of sections of the area inside the defined boundary that are ranked higher than other sections;

computing, by the wireless computing system, a second calculation of a location of the user computing device based on the angle of arrival, the second calculation being performed for an area within each of the identified one or more sections;

generating, by the wireless computing system, location data for the user based on a particular section of the plurality of sections that has results from the second calculation that are most likely to be the actual location of the user computing device; and

transmitting, by the wireless computing system and to the user computing device, the location data to indicate the actual location of the user computing device.

2. The method of claim 1, wherein selecting a particular section of the plurality of sections that has results from the second calculation that are most likely to be the actual location of the user computing device comprises ranking a set of results of the second calculation on each of the plurality of sections based on a likelihood that each of the plurality of sections includes the location of the user computing device, wherein a higher ranking indicates that the likelihood is higher that a particular section includes an actual location of the user computing device than a lower ranking.

3. The method of claim 1, wherein the location data transmitted to the user computing device comprises instructions to display the actual location of the user computing device via a user interface of a mapping application executing on the user computing device.

4. The method of claim 1, wherein a size of the defined boundary encompassing the estimated location of the user computing device is based on an estimated accuracy of the calculation based on the received signal strength, wherein a higher estimated accuracy correlates to a smaller boundary and a lower estimated accuracy correlates to a larger boundary.

5. The method of claim 1, wherein the signal from the user computing device is received by a plurality of wireless access points.

6. The method of claim 1, wherein the signal from the user computing device is received by a single wireless access point.

7. Logic encoded on one or more tangible, non-transitory computer-readable media for execution on a computer and when executed operable to:

receive, by a plurality of access points, a wireless signal from a user computing device;

calculate an estimate of the user computing device relative to the plurality of access points based on the received signal strength of the signal received by the plurality of access points;

calculate a defined boundary encompassing the estimated location of the user computing device;

divide an area inside the boundary into a plurality of sections;

compute a coarse calculation of a location of the user computing device within the area inside the defined boundary based on an angle of arrival of the signal to the plurality of access points;

ranking likelihoods for each of the plurality of sections of being an actual location of the user computing device;

identify one or more sections of the plurality of sections of the area inside the defined boundary that have results from the coarse calculation that are ranked higher than other sections;

compute a fine calculation of a location of the user computing device based on the angle of arrival of the signal received by the plurality of access points, the fine calculation being performed on the identified sections;

select a particular section of the plurality of sections that has results from the fine calculation that are most likely to be the actual location of the user computing device; and

transmit to the user computing device, location data related to the identified particular section of the plurality of sections to indicate the actual location of the user computing device.

8. The logic of claim 7, wherein selecting a particular section of the plurality of sections that has results from the second calculation that are most likely to be the actual location of the user computing device comprises ranking a set of results of the second calculation on each of the plurality of sections based on a likelihood that each of the plurality of sections includes the location of the user computing device, wherein a higher ranking indicates that the likelihood is higher that a particular section includes an actual location of the user computing device than a lower ranking.

9. The logic of claim 7, wherein the transmission of the location data to the user computing device comprises instructions to display the location of the user computing device via a user interface of a mapping application executing on the user computing device.

10. The logic of claim 7, wherein a size of the defined boundary encompassing estimated location of the user computing device is based on an estimated accuracy of the calculation based on the received signal strength, wherein a higher estimated accuracy correlates to a smaller boundary and a lower estimated accuracy correlates to a larger boundary.

11. The logic of claim 7, wherein the signal from the user computing device is received by a single wireless access point.

12. A system, comprising:

a storage device; and

a processor communicatively coupled to the storage device, wherein the processor executes application code instructions that are stored in the storage device to cause the system to;

receive a signal from a user computing device by a wireless computing system access point;

calculate a location estimate of the user computing device relative to the at least one wireless computing system access point and based on a signal strength of the signal received by the at least one wireless computing system access point;

calculate a defined boundary encompassing the estimated location of the user computing device;

divide an area inside the boundary into a plurality of sections;

compute a first calculation of a location of the user computing device within the area inside the defined boundary based on an angle of arrival of the signal received by the at least one wireless computing system access point;

determine a likelihood for each of the plurality of sections of being an actual location of the user computing device;

select one or more sections of the plurality of sections of the area inside the defined boundary that have higher likelihoods of being the actual location of the user computing device;

compute a second calculation of a location of the user computing device based on the angle of arrival of the signal received by the at least one wireless computing system access point, the second calculation being performed on the identified sections; and

determine a particular section of the plurality of sections that has results from the second calculation that are most likely to be the actual location of the user computing device.

13. The system of claim 12, wherein selecting a particular section of the plurality of sections that has results from the second calculation that are most likely to be the actual location of the user computing device comprises ranking a set of results of the second calculation on each of the plurality of sections based on a likelihood that each of the plurality of sections includes the location of the user computing device, wherein a higher ranking indicates that the likelihood is higher that a particular section includes an actual location of the user computing device than a lower ranking.

14. The system of claim 12, wherein the location data transmitted to the user computing device comprises instructions to display the actual location of the user computing device via a user interface of a mapping application executing on the user computing device.

15. The system of claim 12, wherein a size of the defined boundary encompassing the estimated location of the user computing device is based on an estimated accuracy of the calculation based on the RSSI, wherein a higher estimated accuracy correlates to a smaller boundary and a lower estimated accuracy correlates to a larger boundary.

16. The system of claim 12, further comprising application code instructions to communicate to the user computing device, location data related to the identified particular section of the plurality of sections to indicate the actual location of the user computing device.

17. The system of claim 12, wherein the signal from the user computing device is received by a single wireless access point.