Wireless Location-Based System for Detecting Hazardous Conditions

• US 20110161044A1
• Filed: 12/02/2010
• Published: 06/30/2011
• Est. Priority Date: 12/28/2009
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Kolavennu, Soumitri, Cabuz, Cleopatra, Gonia, Patrick S.
• Granted Patent: US 8,442,801 B2
• Time in Patent Office: Days
• US Class Current: 702/150
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: G08B 21/14 Toxic gas alarms G08B21/16 takes precedence

Abstract

A method and apparatus are provided for estimating the location of a portable device. The method includes the steps of providing a plurality of location anchor transceivers and a plurality of enhanced location anchor transceivers within a region, each of the plurality of location anchor transceivers and enhanced location anchor transceivers operating from respective predetermined locations, a portable transceiver within the region detecting and measuring a signal parameter of a signal from at least some of the plurality of location anchor transceivers and enhanced location anchor transceivers within the region, a location engine determining a location of the portable transceiver based upon the signal measurements of the portable transceiver and the respective predetermined locations of the plurality of location anchor transceivers and enhanced location anchor transceivers within the region, each of the plurality of enhanced location anchor transceivers detecting and measuring a signal parameter of a signal from at least some of the plurality of location anchor transceivers and other enhanced location anchor transceivers, the location engine receiving the measured signal parameters from each of the plurality of enhanced location anchor transceivers, the location engine calculating an estimated location for each of the plurality of enhanced location anchor transceivers from the measured signal parameters and the location engine calculating a location error for each of the plurality of enhanced location anchor transceivers based upon the estimated location and predetermined location of the enhanced location anchor transceiver.

Claims

1. A method comprising:

providing a plurality of location anchor transceivers and a plurality of enhanced location anchor transceivers operating from respective predetermined locations within a region;

a portable transceiver within the region detecting and measuring a signal parameter of a signal from at least some of the plurality of location anchor transceivers and enhanced location anchor transceivers;

a location engine calculating an estimated location of the portable transceiver based upon the signal measurements of the portable transceiver and the respective predetermined locations of the plurality of location anchor transceivers and enhanced location anchor transceivers;

at least some of the plurality of enhanced location anchor transceivers detecting and measuring a signal parameter of a signal from at least some of the plurality of location anchor transceivers and other enhanced location anchor transceivers;

the location engine calculating an estimated location of the at least some of the plurality of enhanced location anchor transceivers based upon the signal measurements of the at least some of the enhanced location anchor transceivers and the respective predetermined locations of the plurality of location anchor transceivers and enhanced location anchor transceivers; and

calculating a location error for the at least some of the plurality of enhanced location anchor transceivers based upon the estimated location and predetermined location of the enhanced location anchor transceiver.

2. The method as in claim 1 further comprising the portable transceiver and at least some of the plurality of enhanced location anchor transceivers transmitting a probe request requesting a response from any location anchor transceiver and enhanced location transceiver of the plurality of enhanced location anchor transceivers and location anchor transceivers detecting the probe request.

3. The method as in claim 1 further comprising defining the measured signal parameter by at least one of the portable transceiver and at least some enhanced location anchor transceivers as a received signal strength indication.

4. The method as in claim 1 further comprising displaying to a user an estimated error of the estimated location of the portable transceiver based upon the calculated location error of at least some of the plurality of enhanced location anchor transceivers that are nearest the estimated location of the portable transceiver.

5. The method as in claim 4 wherein the step of displaying the estimated error of the calculated location of the portable transceiver further comprises providing a bounding box around the estimated location of the portable transceiver with the length of the sides of the bounding box being a function of the calculated location errors of at least some of the plurality of enhanced location anchor transceivers nearest the portable transceiver.

6. The method as in claim 1 further comprising generating an alert upon detecting that one of the calculated location errors of the plurality of enhanced location anchor transceivers exceeds a threshold.

7. The method as in claim 1 further comprising the portable transceiver measuring a gas concentration.

19. The method as in claim 1 further comprising the location engine adjusting the estimated location for the portable transceiver based on the location errors for at least some of the plurality of enhanced location anchor transceiver located nearby the estimated location for the portable transceiver.

8. A system for reporting the location of a wireless device, said system comprising:

a plurality of wireless devices including at least some portable devices and at least some stationary devices, the at least some stationary devices operating from respective predetermined locations;

at least one wireless transceiver of the at least some portable devices that wirelessly measures a signal parameter of at least some of the stationary wireless devices and wirelessly communicates information including at least the measured signal parameter;

at least one wireless transceiver of the at least some stationary devices that each wirelessly measures a signal parameter of at least some other of the stationary wireless devices and wirelessly communicates information including at least the measured signal parameter;

at least one transceiver of the plurality of stationary wireless devices that wirelessly communicates with the wireless transceiver of the at least some portable devices and the wireless transceiver of the at least some stationary wireless devices to receive said information including the measured signal parameters;

at least one location engine that calculates an estimated location of the at least some stationary wireless devices based on said predetermined locations and the signal parameters measured by the wireless transceiver of the at least some stationary wireless devices, said at least one location engine further calculates a location error based on the estimated location and the respective predetermined locations, the said at least one location engine further receives signal parameters measured by the wireless transceiver of the at least some portable devices and calculates an estimated location of said at least some portable devices based on said predetermined locations and signal parameters measured by the at least some portable devices; and

at least one location manager for collecting, logging, and displaying said estimated locations of said at least some portable devices.

9. The system as in claim 8 wherein the measured signal parameter further comprises a received signal strength indication.

10. The system as in claim 8 wherein the measured signal parameter further comprises a time of flight.

11. The system as in claim 8 where in the at least one portable device further comprises a gas detection device.

12. A system comprising:

a plurality of location anchor transceivers within a region that each operate from respective predetermined locations;

a plurality of enhanced location anchor transceivers within the region that each operate from respective predetermined locations and that each measure a signal parameter of a signal from at least some of the plurality of location anchor transceivers and other enhanced location anchor transceivers;

a location engine that receives the measured signal parameters from at least some of the plurality of enhanced location anchor transceivers along with an identifier of the enhanced location anchor transceiver and an identifier of a source of each of the measured signal parameters;

the location engine further calculates an estimated location for the at least some of the plurality of enhanced location anchor transceivers from the measured signal parameters, the location engine calculates a location error for the at least some of the plurality of enhanced location anchor transceivers based upon the estimated location and predetermined location of the enhanced location anchor transceiver; and

a portable transceiver within the region that detects and measures a signal parameter of a signal from at least some of the plurality of location anchor transceivers and enhanced location anchor transceivers and wherein the location engine determines a location of the portable transceiver based upon the signal measurements of the portable transceiver, and the predetermined locations of the enhanced location anchor transceivers and location anchor transceivers.

13. The system as in claim 12 further comprising a probe request transmitted by the portable transceiver and by at least some of the enhanced location and anchor transceivers, the probe request requesting a response from any location anchor transceiver and enhanced location transceiver of the plurality of enhanced location anchor transceivers and location anchor transceivers detecting the probe.

14. The system as in claim 12 where the measured signal parameters further comprise a received signal strength indication.

15. The system as in claim 12 further comprising a display that displays to a user an estimated error of the calculated location of the portable transceiver based upon the calculated location errors of the plurality of enhanced location anchor transceivers.

16. The system as in claim 12 further comprises a bounding area provided around the calculated location of the portable transceiver with size of the bounding area directly proportional to the calculated location error of at least some of the plurality of enhanced location anchor transceivers.

17. The system as in claim 12 further comprising an alert provided to a user upon detecting that one of the calculated location errors of the plurality of enhanced location anchor transceivers exceeds a threshold.

18. The system as in claim 12 further comprising the portable transceiver measuring a gas concentration.

20. The system as in claim 18 further comprising at least some of the enhanced location transceivers measuring a gas concentration.