METHOD AND SYSTEM FOR LOCATING WIRELESS DEVICES WITHIN A LOCAL REGION

• US 20150070218A1
• Filed: 02/21/2014
• Published: 03/12/2015
• Est. Priority Date: 09/06/2013
• Status: Active Grant

• Current Assignee: DRNC Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Tag-Comm Inc.
• Inventors: MANKU, TAJINDER
• Granted Patent: US 9,958,533 B2
• Time in Patent Office: Days
• US Class Current: 342/458
• CPC Class Codes: G01S 13/767 Responders; Transponders teaching or practice apparatus for gun-aiming or gun-laying using reflecting targets or active targets F41G3/26
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination

Abstract

A method for locating wireless devices within a local region, comprising: determining respective global locations of two or more of the wireless devices; determining whether the wireless devices are within the local region by calculating respective distances between the global locations; determining respective ranges between the wireless devices within the local region; and, determining respective relative locations of the wireless devices within the local region by triangulation using the ranges.

Claims

1. A method for locating wireless devices within a local region, comprising:

determining respective global locations of two or more of the wireless devices;

determining whether the wireless devices are within the local region by calculating respective distances between the global locations;

determining respective ranges between the wireless devices within the local region; and

,

determining respective relative locations of the wireless devices within the local region by triangulation using the ranges.

2. The method of claim 1 wherein the determining the respective ranges between the wireless devices within the local region includes:

transmitting respective original signals from the wireless devices;

in response to the respective original signals, receiving respective modulated signals at ones of the wireless devices from others of the wireless devices, the modulated signals being backscattered from the others of the wireless devices, the modulated signals being frequency offset versions of the original signals; and

, determining the ranges between the wireless devices from the modulated signals.

3. The method of claim 2 and further comprising measuring respective powers of the modulated signals, the powers of the modulated signals being inversely proportional to the ranges between the respective wireless devices to the fourth power.

4. The method of claim 2 wherein the respective original signals are transmitted sequentially from the wireless devices.

5. The method of claim 1 wherein the ranges are determined by respective radio frequency identification systems included in the wireless devices.

6. The method of claim 1 wherein the global locations are determined using respective global positioning system receivers included in the wireless devices.

7. The method of claim 1 wherein the respective original signals are respective original radar signals and wherein the respective modulated signals are respective modulated radar signals.

8. The method of claim 1 wherein the ranges are distances between the wireless devices.

9. The method of claim 1 and further comprising storing the relative locations in a memory of at least one of the wireless devices.

10. The method of claim 1 and further comprising presenting the relative locations on a display of at least one of the wireless devices.

11. A system for locating wireless devices within a local region, comprising:

a processor coupled to memory, a transmitter, and a receiver; and

,

at least one of hardware and software modules within the memory and controlled or executed by the processor, the modules including;

a module for determining respective global locations of two or more of the wireless devices;

a module for determining whether the wireless devices are within the local region by calculating respective distances between the global locations;

a module for determining respective ranges between the wireless devices within the local region; and

,

a module for determining respective relative locations of the wireless devices within the local region by triangulation using the ranges.

12. The system of claim 11 wherein the module for determining the respective ranges between the wireless devices within the local regions includes:

a module for controlling the transmitter to transmit an original signal from the system;

a module for controlling the receiver to, in response to the original signal, receive respective modulated signals at the system from the wireless devices, the modulated signals being backscattered from the wireless devices, the modulated signals being frequency offset versions of the original signal; and

, a module for determining the ranges between the wireless devices and the system from the modulated signals.

13. The system of claim 12 and further comprising a module for measuring respective powers of the modulated signals, the powers of the modulated signals being inversely proportional to the ranges between the respective wireless devices and the system to the fourth power.

14. The system of claim 12 wherein the respective original signals are transmitted sequentially from the system.

15. The system of claim 11 wherein the ranges are determined by a radio frequency identification system included in the system.

16. The system of claim 11 wherein the global locations are determined using respective global positioning system receivers included in the wireless devices and in the system.

17. The system of claim 11 wherein the respective original signals are respective original radar signals and wherein the respective modulated signals are respective modulated radar signals.

18. The system of claim 11 wherein the ranges are distances between the wireless devices.

19. The system of claim 11 and further comprising a module for storing the relative locations in a memory of the system.

20. The system of claim 11 and further comprising a module for presenting the relative locations on a display of the system.