Wireless location-based system for detecting hazardous conditions

• US 8,442,801 B2
• Filed: 12/02/2010
• Issued: 05/14/2013
• Est. Priority Date: 12/28/2009
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Kolavennu, Soumitri, Cabuz, Cleopatra, Gonla, Patrick S.
• Primary Examiner(s): HENSON, MISCHITA L
• Application Number:
  US12/959,250
• Publication Number:
  US 20110161044A1
• Time in Patent Office: 894 Days
• Field of Search: 702/127, 702/150, 702/152, 702/189
• 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 providing a plurality of location anchor and enhanced location anchor transceivers within a region, each operating from respective predetermined locations, a portable transceiver measuring a signal parameter from the transceivers, a location engine determining a location of the portable transceiver based upon the signal measurements and the respective predetermined locations of the transceivers, each of the enhanced transceivers measuring a signal parameter from some of the location and other enhanced transceivers, the location engine calculating an estimated location for each of the plurality of enhanced transceivers and calculating a location error 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 at least some of the enhanced anchor transceivers including a respective gas detector;

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, the portable transceiver including a gas detector;

the gas detectors of the portable transceiver and at least some enhanced location anchor transceivers measuring and reporting a gas concentration to a location manager module;

a location engine of the location manager module 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;

calculating a location error for the portable transceiver and each of 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 display of the location manager module depicting a map of the region including a designated location of at least some of the plurality of enhanced location anchor transceivers, an estimated location of the portable transceiver, a gas concentration profile across the region and a location error of the portable 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 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, the at least some portable devices each including a respective gas detector, the plurality of wireless devices also including at least some stationary devices, the stationary devices including one or more respective gas detectors, the at least some stationary devices operating from respective predetermined locations, the at least some portable devices and the at least some stationary devices with gas detectors measuring and reporting a gas concentration to a location manager module;

at least one wireless transceiver of the at least some portable devices that wirelessly measures a signal parameter each 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 each of the at least some portable devices and also the wireless transceiver of the at least some other of the stationary wireless devices to receive said information including the measured signal parameters;

at least one location engine of the location manager module that calculates an estimated location of each of the at least some stationary wireless devices based on said predetermined locations and the signal parameter 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 the signal parameter measured by the wireless transceiver of the at least some portable devices and calculates an estimated location of each of said at least some portable devices based on said predetermined locations and the signal parameter measured by the at least some portable devices; and

the location manager module collects, logs and displays a gas concentration profile based upon the reported gas concentrations across a predetermined area along with said estimated locations of said at least some portable devices shown within the predetermined area.

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

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

11. The system as in claim 8 wherein 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 different 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 at least some of the plurality of enhanced location anchor transceiver including a respective gas detector that measures and reports a gas concentration to a location manager module;

a location engine of the manager module 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;

a portable transceiver within the region that detects and reports a gas concentration and 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; and

a display of the location manager module that depicts a map of the region including a designated location of at least some of the plurality of enhanced location anchor transceivers, an estimated location of the portable transceiver, a gas concentration profile across the region based upon the reported gas concentrations and a location error of the portable transceiver.

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.