LOCALIZATION IDENTIFICATION SYSTEM FOR WIRELESS DEVICES

• US 20070077941A1
• Filed: 10/05/2005
• Published: 04/05/2007
• Est. Priority Date: 10/05/2005
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Gonia, Patrick, Mahasenan, Arun, Kore, Vinayak
• Granted Patent: US 7,603,129 B2
• Time in Patent Office: Days
• US Class Current: 455/456.100
• CPC Class Codes: G01S 1/66 Superimposing direction-indicating intelligence signals, e.g. speech, Morse
• CPC Class Codes: G01S 5/0226 Transmitters
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location

Abstract

Wireless devices, systems and approaches or methods having the capability of determining the location of a given wireless device. An example system includes a wireless device that generates at least one pulse as a part of an output signal, and the at least one pulse is captured by anchor devices and used, in a time of arrival approach, to determine the location of the example device. The at least one pulse may be generated during a designated portion of an otherwise normally modulated message. Another example system includes an anchor node that generates a directional output signal, the direction output signal including data indicating its direction, and the directions of output signals from plural anchor nodes when pointed at a wireless device are used to determine the location of the wireless device. Combinations of the pulse and directional antenna systems, devices used within each of these systems, and approaches associated with these systems are also included.

Claims

1. A method of determining the location of a wireless device, the method comprising:

providing a wireless device and a plurality of anchor nodes, the anchor nodes having known locations and a synchronized sense of time;

generating a message from the wireless device, the message including a preamble, a data portion, and a postamble;

during at least one of the preamble, the data portion, and the postamble, generating at least one pulse from the wireless device;

receiving the message and the pulse at more than one of the plurality of anchor nodes; and

comparing the times at which the more than one anchor nodes received the pulse.

2. The method of claim 1 wherein the anchor nodes determine which of a plurality of devices generated the at least one pulse by observing a portion of the message including source address data.

3. The method of claim 1 wherein the more than one anchor node includes first, second, third and fourth anchor nodes.

4. The method of claim 1 wherein the message is generated using a carrier signal that is modulated according to a modulation protocol, wherein the at least one pulse is generated by modifying the carrier signal in a manner inconsistent with the modulation protocol.

5. The method of claim 1 wherein the at least one pulse is generated in the postamble and the message includes an indication that the at least one pulse will occur in the postamble.

6. The method of claim 5 wherein at least one of the anchor nodes includes a locator circuit adapted to observe the time of receipt of the at least one pulse, wherein the method includes activating the locator circuit during a time corresponding to an expected time that the at least one pulse will be received.

7. The method of claim 1 further comprising:

providing another device having a known location, the another device including a directional antenna;

capturing a signal generated with the directional antenna; and

determining the direction of greatest sensitivity of the directional antenna at the time the signal from the wireless device is captured.

8. The method of claim 7 further comprising combining directional information from the another device and pulse time of arrival information from the anchor devices to determine the location of the wireless device.

9. The method of claim 1 further comprising:

providing another device having a known location, the another device including a directional antenna;

generating a directional signal from the directional antenna, the signal including data related to a direction the antenna is pointing at a given time and data related to the another device; and

capturing the directional signal with the wireless device.

10. The method of claim 9 further comprising the wireless device determining its location using data from the captured directional signal.

11. A wireless device comprising generating circuitry that generates a carrier signal, and modulating circuitry that modulates the carrier signal relative to data for transmission, the device further comprising pulse creation circuitry adapted to selectively create one or more pulses in association with the carrier signal, the one or more pulses being generated in a manner inconsistent with a modulation protocol associated with modulation of the carrier signal by the modulating circuitry.

12. The wireless device of claim 11 wherein the device is adapted to create a message by use of the circuitry for generating and the circuitry for modulating, wherein the device also comprises a controller that controls the pulse creation circuitry and selectively causes the carrier signal to be modified inconsistent with the modulation protocol during a designated portion of a selected message, the selected message also including source identifier data.

13. The wireless device of claim 12 wherein the pulse creation circuitry clamps a portion of the carrier signal.

14. A wireless communication system comprising:

a wireless device as in claim 11;

and

a plurality of anchor nodes, wherein a first anchor node comprises circuitry for communicating wirelessly with the wireless device of claim 11, the first anchor node further comprising pulse detection circuitry for detecting when the one or more pulses are received at the first anchor node.

15. The system of claim 14 wherein the first anchor node includes an antenna coupled via amplification circuitry to a demodulator, wherein the pulse detection circuitry takes an output from the amplification circuitry that couples the antenna to the demodulator.

16. The system of claim 14 wherein the first anchor node includes an antenna coupled via signal amplification circuitry to a demodulator, wherein the pulse detection circuitry takes an output from separate amplification circuitry different from the signal amplification circuitry.

17. The system of claim 14 wherein the pulse detection circuitry of the first anchor node is adapted to receive a pulse generated when the wireless device selectively causes the carrier signal to be modulated inconsistent with the modulation protocol.

18. The system of claim 14 further comprising a second anchor node that includes a directional antenna capable of preferential signal capture along a first direction, the second anchor node adapted to cause the directional antenna to change the direction of the preferential signal capture, the second anchor node being adapted to determine a direction from which a received signal is generated.

19. The system of claim 14 wherein a second anchor node includes a directional antenna capable of generating a directional signal such that the directional signal, when directed from the second anchor node in a first direction, generates data as part of the directional signal indicative of the first direction.

20. The system of claim 19 wherein the wireless device is further adapted to receive the directional signal and determine its direction with respect to the second anchor node.

21. A wireless communication system comprising:

a wireless device as in claim 11;

and

a plurality of anchor nodes having known locations, a first of the anchor nodes adapted to receive a pulse from the wireless device and determine a time of reception, and a second of the anchor nodes adapted to produce directional output signals, the directional output signals including indicators of relative direction of the directional output signal at a given time;

such that the wireless communication system includes devices adapted for both directional and pulse-based localization of devices therein.

22. A wireless communication system comprising:

a first anchor node adapted to receive a transmission from a distributed node using at least a first modulation protocol, the first anchor node having a sense of time synchronization and known locations with reference to a second node, the first anchor nodes being adapted to observe, in at least some transmissions modulated with the first modulation protocol, one or more pulses created by modification of a carrier in a manner inconsistent with the first modulation protocol;

a second anchor node having a known location and a directional antenna;

wherein the wireless communication system is adapted to perform localization of distributed nodes therein by the use of a time of arrival method for at least some distributed nodes and a directional method for at least some other distributed nodes.

23. The system of claim 22 wherein the wireless communication system is adapted to perform localization of at least some distributed nodes using a combination of directional and time of arrival data.

24. The system of claim 22 wherein the second anchor node is adapted to generate a directional transmission containing information related to the identification of the second anchor node and the direction of transmission.

25. The system of claim 22 wherein the second anchor node is adapted to receive a transmission containing identification of a distributed node and determine the direction from which the transmission is received.

26. The system of claim 22 wherein the first anchor node is further adapted to expect the one or more pulses during a designated portion of message transmission.