DETERMINING LOCATION VIA CURRENT AND PREVIOUS WIRELESS SIGNAL ATTRIBUTES

• US 20170280281A1
• Filed: 06/03/2016
• Published: 09/28/2017
• Est. Priority Date: 03/22/2016
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Pandey, Santosh, Peng, Rong
• Granted Patent: US 9,860,692 B2
• Time in Patent Office: Days
• CPC Class Codes: G01C 21/206 specially adapted for indoor navigation
• 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: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/373 Predicting channel quality or other radio frequency [RF] parameters
• CPC Class Codes: H04W 4/02 Services making use of location information
• 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 system supported by wireless access points receiving signals from a user device. The wireless system estimates a location of the user device based on a coarse calculation based on an angle of arrival of the received signal and determines if the user device is in an area under an access point. The wireless system identifies received signal strength indicator values for the user device and uses the values and the calculated location of the user device to improve calibration of a received signal strength location model. If the system determines that the user is not in the area under the access point, the wireless system combines the coarse calculation location, a received signal strength determined location, and a previous received signal strength determined location, and estimates a location based on the combined calculations.

Claims

1. A method, comprising:

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

calculating, using the computing system, a first estimated location of the user computing device based on an angle of arrival of the received wireless signal with respect to each of the at least one wireless computing system access point;

calculating, using the computing system, a current received signal strength indicator (“

RSSI”

) estimated location of the user computing device based on a signal strength of the received wireless signal with respect to each of the at least one wireless computing system access point;

determining, using the computing system, whether an elapsed time between calculating the current RSSI estimated location of the user computing device and a previously calculated RSSI estimated location of the user computing device is within a configured time interval;

in response to a determination that an elapsed time between calculating the current RSSI estimated location of the user computing device and the previously calculated RSSI estimated location of the user computing device is within the configured time interval, calculating, using the computing system, a second estimated location of the user computing device based on a combination of results of the first estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the previously calculated RSSI estimated location of the user computing device and the current RSSI estimated location of the user computing device; and

transmitting, using the computing system and to the user computing device, location data related to the second estimated location to indicate an actual location of the user computing device.

2. The computer-implemented method of claim 1, wherein combining the results of the first estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the previously calculated RSSI estimated location of the user computing device and the current RSSI estimated location of the user computing device comprises averaging the results.

3. The computer-implemented method of claim 1, wherein the location data transmitted to the user computing device comprises instructions to display the second estimated location of the user computing device on a mapping application executing on the user computing device.

4. The computer-implemented method of claim 1, wherein the wireless signal is a Wi-Fi signal.

5. The computer-implemented method of claim 1, wherein the second estimated location of the user computing device is more accurate than the first estimated location of the user computing device.

6. The computer-implemented method of claim 1, wherein the signal from the user computing device is received by a plurality of access points and received signal strength values are communicated to the computing system from each of the plurality of access points.

7. The computer-implemented method of claim 1, further comprising:

in response to a determination that an elapsed time between calculating the current RSSI estimated location of the user computing device and the previously calculated RSSI estimated location of the user computing device is not within the configured time interval, calculating, using the computing system, a third estimated location of the user computing device based on a combination of results of the first estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the current RSSI estimated location of the user computing device; and

transmitting, using the computing system and to the user computing device, location data related to the third estimated location to indicate an actual location of the user computing device.

8. A tangible, non-transitory, computer-readable media having software encoded thereon, the software when executed by a processor operable to:

receive, by at least one wireless computing system access point, a wireless signal from a user computing device;

calculate a first estimated location of the user computing device based on an angle of arrival of the received wireless signal with respect to each of the at least one wireless computing system access point;

calculate a first received signal strength indicator (“

RSSI”

) estimated location of the user computing device based on a signal strength of the received wireless signal with respect to each of the at least one wireless computing system access point;

calculate a second estimated location of the user computing device based on a combination of the first estimated location of the user computing device with the results of the calculated first RSSI estimated location of the user computing device;

transmit, to the user computing device, location data related to the second estimated location to indicate an actual location of the user computing device;

receive a second wireless signal from the user computing device;

calculate a third estimated location of the user computing device based on an angle of arrival of the second received wireless signal with respect to each of the at least one wireless computing system access point;

calculate a second RSSI estimated location of the user computing device based on a received signal strength values of the received wireless signal with respect to each of the at least one wireless computing system access point;

determine whether an elapsed time between calculating the second RSSI estimated location of the user computing device and the first RSSI estimated location of the user computing device is within a configured time interval;

upon a determination that an elapsed time between calculating the first RSSI estimated location of the user computing device and the second RSSI estimated location of the user computing device is within the configured time interval, access the first RSSI estimated location of the user computing device;

calculate a fourth estimated location of the user computing device based on a combination of results of the calculation based on a combination of results of the third estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the first RSSI estimated location of the user computing device and the second RSSI estimated location of the user computing device; and

transmit, to the user computing device, location data related to the fourth estimated location to indicate an actual location of the user computing device

9. The computer-readable media of claim 8, wherein combining the results of the third estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the first RSSI estimated location of the user computing device and the second RSSI estimated location of the user computing device comprises averaging the results.

10. The computer-readable media of claim 8, wherein the location data related to the fourth estimated location transmitted to the user computing device comprises instructions to display the fourth estimated location of the user computing device on a mapping application executing on the user computing device.

11. The computer-readable media of claim 8, wherein the wireless signal is a Wi-Fi signal.

12. The computer-readable media of claim 8, wherein the fourth estimated location of the user computing device is more accurate than the second estimated location of the user computing device.

13. The computer-readable media of claim 8, wherein the signal from the user computing device is received by a plurality of access points and received signal strength values are communicated to the computing system from each of the plurality of access points.

14. 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, by at least one wireless computing system access point, a wireless signal from a user computing device;

calculate a first estimated location of the user computing device based on an angle of arrival of the received wireless signal with respect to each of the at least one wireless computing system access point;

calculate a current received signal strength indicator (“

RSSI”

) estimated location of the user computing device based on a received signal strength values of the received wireless signal with respect to each of the at least one wireless computing system access point;

calculating a second estimated location of the user computing device based on a combination of results of the first estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the previously calculated RSSI estimated location of the user computing device and the current RSSI estimated location of the user computing device.

15. The system of claim 14, wherein combining the results of the first estimated location of the user computing device based on the angle of arrival of the received wireless signal with results of the previously calculated RSSI estimated location of the user computing device and the current RSSI estimated location of the user computing device comprises averaging the results.

16. The system of claim 14, wherein the wireless signal is a Wi-Fi signal.

17. The system of claim 14, wherein the second estimated location of the user computing device is more accurate than the first estimated location of the user computing device.

18. The system of claim 14, wherein the signal from the user computing device is received by a plurality of access points and received signal strength values are communicated to the computing system from each of the plurality of access points.

19. The system of claim 14, further comprising application code instructions to transmit, to the user computing device, location data related to the second estimated location to indicate an actual location of the user computing device

20. The system of claim 14, further comprising application code instructions to:

calculating, using the computing system, a third estimated location of the user computing device based on a combination of results of the calculation based on the angle of arrival of the received subsequent signal with results of an application of the calculated received signal strength values of the subsequent signal to the updated received signal strength model; and

transmitting, using the computing system and to the user computing device, location data related to the third estimated location to indicate an actual location of the user computing device.