METHOD AND APPARATUS FOR DETERMINING POSITION OF A WIRELESS DEVICE

• US 20130172019A1
• Filed: 06/29/2012
• Published: 07/04/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Michel Fattouche, Mohamed Youssef, Naser El-Sheimy
• Original Assignee: Michel Fattouche, Mohamed Youssef, Naser El-Sheimy
• Inventors: Fattouche, Michel, Youssef, Mohamed, El-Sheimy, Naser
• Granted Patent: US 8,792,908 B2
• Time in Patent Office: Days
• US Class Current: 455/456.6
• CPC Class Codes: G01S 5/0218 Multipath in signal reception
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A method and apparatus for determining the location of a device capable of receiving/transmitting wireless signals from/to reference stations is provided, for example providing wireless signals in the form of range information to the device; determining a region or area surrounding each reference station, wherein regions intersect to form intersecting spaces; defining the intersecting spaces to delineate a device location search space and determining device locations within the search space; determining combinations of said device locations, and using a distribution analysis test to examine a skewness value of each combination; detecting and selecting the combinations of device positions that result in a minimum skewness value or simply a combination that provides skewness value less than a pre-defined minimum threshold value; and utilizing the detected and selected combinations to determine a refined final position of the device.

Claims

1. A method for determining the location of a device, wherein the device is capable of receiving/transmitting wireless signals from/to reference stations, the method comprising:

providing wireless signals in the form of range information to the device, from at least three reference stations;

determining a region or area surrounding each reference station, wherein each region surrounding each reference station intersects with at least one region surrounding at least one other reference station to form at least one intersecting space;

defining the at least one intersecting space to delineate a device location search space;

determining locations of the device within the device location search space;

determining combinations of said device locations, and using a distribution analysis test to examine a skewness value of each combination;

detecting and selecting the combinations of device positions that result in a minimum skewness value or a combination that provides a skewness value less than a pre-defined minimum threshold value; and

utilizing the detected and selected combinations to determine a refined final position of the device.

2. The method of claim 1, wherein the wireless signal range information is selected from the group consisting of radio signals and sound signals.

3. The method of claim 1, wherein the reference station comprises a station having known coordinates selected from the group consisting of Cellular Base-Stations, GNSS satellite, WLAN/Wi-Fi Routers, and Base-Stations for Network-based location.

4. The method of claim 1, wherein the ranging information is processed and extracted by a super-resolution technique.

5. The method of claim 1, wherein the region surrounding the reference station is in the form of a circle, having a diameter or radius that may be determined.

6. The method of claim 1, wherein the distribution analysis test comprises a mean minus median analysis.

7. The method of claim 6, wherein the mean is a sampled mean and the median is a sampled median.

8. The method of claim 1, wherein the distribution analysis test comprises a conventional skewness and Kurtosis analysis.

9. The method of claim 1, wherein the pre-defined minimum threshold value is based on system design parameters selected from the group consisting of system bandwidth and minimum target SNR.

10. The method of claim 1, wherein the location of the device is determined in scenario selected from the group consisting of a two-dimensional (2D) scenario and a three-dimensional (3D) scenario.

11. The method of claim 1, wherein the location of the device is determined by providing any processing or computation steps at the device itself.

12. The method of claim 1, wherein the location of the device is determined by providing any processing or computation steps at a network server.

13. The method of claim 1, wherein the location of the device is determined by having the device collect at least one raw digitized signal and send the at least one raw digitized signal back to a hosted-server using TCP/IP protocol, where the any processing or computation steps take place on the hosted-server.

14. A device capable of receiving/transmitting wireless signals in the form of range information from/to a reference station, the device comprising:

receiver/transmission means for receiving/transmitting wireless signals from/to at least three reference stations;

processing means capable of receiving the wireless signals and;

determining a region or area surrounding each reference station, wherein the region surrounding one reference station intersects with at least one region surrounding at least one other reference station to form at least one intersecting space;

defining the at least one intersecting space to delineate a device location search space;

determining locations of the device within the receiver location search space;

determining combinations of said receiver locations, and using a distribution analysis test to examine a skewness value of each combination;

detecting and selecting the combinations of device positions that result in a minimum skewness value or a combination that provides skewness value less than a pre-defined minimum threshold value; and

utilizing the detected and selected combinations to determine a refined final position of the device.

15. The device of claim 14, wherein the device is selected from the group consisting of a portable radio device, a mobile phone, a Global Positioning System device, and a beacon device.

16. The device of claim 14, wherein the device further comprises a processor capable of using techniques selected from the group consisting of Matched filter(s) and correlator(s), followed by a peak detector.

17. The device of claim 14, wherein the wireless signal range information is selected from the group consisting of radio signals and sound signals.

18. The device of claim 14, wherein the reference station comprises a station having known coordinates selected from the group consisting of Cellular Base-Stations, GNSS satellite, WLAN/Wi-Fi Routers, and Base-Stations for Network-based location.

19. The device of claim 14, wherein the distribution analysis test comprises a mean minus median analysis.

20. The device of claim 14, wherein the pre-defined minimum threshold value is based on system design parameters selected from the group consisting of system bandwidth and minimum target SNR.