Determining a designated wireless device lacks a fixed geographic location and using the determination to improve location estimates

Patent metadata

Field	Value
Publication number	US-9521512-B2
Application number	US-201514635641-A
Country	US
Kind code	B2
Filing date	Mar 2, 2015
Priority date	Jun 11, 2010
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

In one embodiment, a system determines a designated wireless device lacks a fixed geographic location, and uses the determination that the designated wireless device lacks a fixed geographic location to improve location estimates. The system determines one or more neighboring wireless devices have relationships with the designated wireless device, wherein a relationship is established when wireless signals from a neighboring wireless device and the designated wireless device are detected by a same receiver. A measure of likelihood is calculated that the designated wireless device lacks a fixed geographic location based at least in part on a number of the relationships or a duration of the relationships. Based on the measure of likelihood, the designated wireless device is excluded from being used in the wireless positioning system as a beacon for estimating the location of a client device.

First claim

What is claimed is:

1. A method of determining that a geographic location of a designated wireless device is not fixed, and using the determination that the geographic location of the designated wireless device is not fixed to improve location estimates, the method comprising:
determining, by a wireless positioning system, one or more neighboring wireless devices having relationships with the designated wireless device, wherein a relationship is established when wireless signals from a neighboring wireless device of the one or more neighboring wireless devices and the designated wireless device are detected by a same receiver;
calculating a measure of likelihood that the geographic location of the designated wireless device is not fixed based at least in part on a number of the relationships or a duration of the relationships; and
based on the measure of likelihood, excluding the designated wireless device from being used in the wireless positioning system as a beacon for estimating the location of a client device.

2. The method of claim 1 , wherein the designated wireless device and the one or more neighboring wireless devices are Wi-Fi access points.

3. The method of claim 1 , wherein the measure of likelihood is based at least in part on the number of the relationships, and the calculating further comprises:
comparing the number of relationships with a threshold number that if exceeded is indicative that the geographic location is not fixed.

4. The method of claim 3 , wherein the threshold number is based on the number of relationships associated with the one or more neighboring wireless devices.

5. The method of claim 4 , wherein the threshold number is a given percentile of the number of relationships associated with the one or more neighboring wireless devices.

6. The method of claim 1 , wherein the measure of likelihood is based at least in part on the duration of the relationships, and the calculating further comprises:
comparing the duration of the relationships with a threshold time that when not met is indicative that the geographic location is not fixed.

7. The method of claim 6 , wherein the threshold time is based on a distribution of durations of relationships of wireless devices that have geographic location that is fixed and wireless devices that have geographic locations that is not fixed.

8. The method of claim 1 , wherein the measure of likelihood is based at least in part on a function that combines the number of the relationships and the duration of the relationships, wherein the function provides that a greater number of relationships and a lesser duration of relationships is indicative that the geographic location is not fixed.

9. The method of claim 1 , wherein the measure of likelihood is further based at least in part on a comparison of an identifier or manufacturer associated with the designated wireless device with a list of identifiers or manufactures known to correspond to mobile wireless devices.

10. The method of claim 1 , wherein the measure of likelihood is further based at least in part on a number of relocations of the designated wireless device during a time interval, wherein the number of relocations is determined from a record of each instance an estimated location of the designated wireless device changed in a database.

11. A method of determining that geographic location of a designated wireless device is not fixed, and using the determination that the geographic location of the designated wireless device is not fixed to improve location estimates, the method comprising:
maintaining, by a wireless positioning system, a database that includes an estimated location of the designated wireless device;
maintaining, by the wireless positioning system, a record of each instance the estimated location of the designated wireless device changed in the database;
using the record to determine a number of relocations of the designated wireless device during a time interval;
in response to the number of relocations exceeding a relocation threshold, determining that the geographic location of the designated wireless device is not fixed; and
based on the geographic location of the designated wireless device being determined to not be fixed, excluding the designated wireless device from being used in the wireless positioning system as a beacon for estimating a location of a client device.

12. The method of claim 11 , wherein the designated wireless device is a Wi-Fi access points.

13. The method of claim 11 , wherein the relocation threshold is based on a frequency of updates in the wireless positioning system.

14. A wireless positioning system configured to determine that geographic location of a designated wireless device is not fixed, and use the determination that the geographic location of the designated wireless device is not fixed to improve location estimates, comprising:
a computer system configured to estimate location of client devices; and
a non-transitory computer readable media including instructions that when executed by the computer system cause the computer system to:
determine one or more neighboring wireless devices that have relationships with a designated wireless device, wherein a relationship is established when wireless signals from a neighboring wireless device of the one or more neighboring wireless devices and the designated wireless device are detected by a same receiver;
determine whether the geographic location of the designated wireless device is not fixed based at least in part on the relationships; and
use the determination that the geographic location of the designated wireless device is not fixed in a determination whether to select the designated wireless device to be used as a beacon in the wireless positioning system for estimating the location of client devices.

15. The wireless positioning system of claim 14 , wherein the designated wireless device and the one or more neighboring wireless devices are Wi-Fi access points.

16. The wireless positioning system of claim 14 , wherein the determination whether the geographic location of the designated wireless device is not fixed is based at least in part on a number of the relationships.

17. The wireless positioning system of claim 16 , wherein the instructions when executed by the computer system cause the computer system to compare the number of relationships with a threshold number that if exceeded is indicative of a-the lack of any fixed geographic location.

18. The wireless positioning system of claim 14 , wherein the determination whether the geographic location of the designated wireless device is not fixed geographic location is based at least in part on a duration of the relationships.

19. The wireless positioning system of claim 18 , wherein the instructions when executed by the computer system cause the computer system to compare the number of relationships with a threshold time that when not met is indicative that the geographic location is not fixed.

20. The wireless positioning system of claim 14 , wherein the determination whether the geographic location of the designated wireless device is not fixed produces a probability, and the determination whether to select the designated wireless device to be used as the beacon in the wireless positioning system is based on the probability.

21. The wireless positioning system of claim 14 , wherein the determination whether the geographic location of the designated wireless device is not fixed produces a binary result and the de

Assignees

• Skyhook Wireless Inc

Inventors

• Alizadeh-Shabdiz Farshid
• Brachet Nicolas
• Cavanaugh Gerald
• Dancus Andrei
• Jones Russel K
• Steger Christopher

Classifications

• G01S5/0252

  Radio frequency fingerprinting · CPC title

• G01S1/024

  of beacon transmitters · CPC title

• H04W64/00 Primary

  Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management · CPC title

• H04W24/00

  Supervisory, monitoring or testing arrangements · CPC title

• G01S5/021

  Calibration, monitoring or correction (G01S5/0252 takes precedence) · CPC title