System and method for identifying the floor number where a firefighter in need of help is located using received signal strength indicator and signal propagation time

• US 20040246926A1
• Filed: 06/04/2004
• Published: 12/09/2004
• Est. Priority Date: 06/06/2003
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: MeshNetworks, Inc. (Motorola Solutions, Inc.)
• Inventors: AʼRafat, SaʼEd, Green, James, Schmidt, Jeffrey C., Belcea, John M., Welsh, Shawn P., Roberson, Allen M., Hill, Philip J.
• Granted Patent: US 7,126,951 B2
• Time in Patent Office: Days
• US Class Current: 370/332
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 40/00 Communication routing or communication path finding
• CPC Class Codes: H04W 52/46 in multi hop networks, e.g. wireless relay networks
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

A system and method for deploying a network of wireless devices, including mobile terminals, wireless routers and a least one control console, within a three dimensional deployment area such as a building, so that communication, identification and position calculations of personnel, such as firefighters, using the mobile terminals can be achieved regardless of building structure. The wireless routers are deployed in a substantial vertical manner in staircases and elevator shafts of a building of interest, either in advance as part of a safety program or immediately upon arrival of firefighters or other team at the building during an emergency. The system and method according to the embodiment of the present invention described herein uses both TOF and RSSI between the mobile terminals and wireless routers to identify the floor numbers where firefighters are located and to track firefighter movements.

Claims

1. A system for monitoring movement in a three-dimensional multi-level structure, comprising:

a plurality of mobile wireless remote terminals, adapted to communicate in a wireless ad-hoc multi-hopping and peer-to-peer communication network; and

a plurality of wireless routers, deployable in the three-dimensional area, and adapted to communicate in the wireless ad-hoc multi-hopping and peer-to-peer communication network;

each of the mobile wireless remote terminals being adapted to exchange signals with any of the routers within its broadcast range and, based on those signals, being adapted to determine its location in the three-dimensional structure.

2. A system as claimed in claim 1, wherein:

said each mobile wireless remote terminal uses time of flight (TOF) data and received signal strength indicator (RSSI) data pertaining to the signals received from said any of the routers within its broadcast range to determine its location in the three-dimensional structure.

3. A system as claimed in claim 2, wherein:

the three-dimensional structure is a building, and the routers are deployed on respective floors of the building; and

said each mobile wireless remote terminal assigns respective scores to each floor based on the TOF data and RSSI data pertaining to the signals, and determines its location as a floor on which it is present based on the scores.

4. A system as claimed in claim 3, wherein:

said each mobile terminal identifies the floor on which it is present as the floor having the lowest score.

5. A system as claimed in claim 2, wherein:

said each mobile wireless remote terminal uses the TOF data and the RSSI data pertaining to the signals received from the routers within a certain time proximate to a time at which it determines its location based on the TOF data and the RSSI data, and refrains from using the TOF data and the RSSI data pertaining to the signals received prior to the certain time.

6. A system as claimed in claim 1, further comprising:

a control console, adapted to receive information from the mobile terminals pertaining to their respective determined locations, and to generate a display illustrating positions of the mobile terminals in the three-dimensional location.

7. A system as claimed in claim 6, wherein:

the three-dimensional location is a building, and the routers are deployed on respective floors of the building; and

the control console is adapted to generate the display illustrating the locations of the mobile terminals on the floors of the building.

8. A system as claimed in claim 6, wherein:

said each mobile terminals includes a respective motion sensor and said each mobile terminal transmits data received from its respective motion sensor to the control console; and

the control console is adapted to generate an alarm condition identifying a particular mobile terminal if the data received from a motion sensor associated with that mobile terminal indicates that that mobile terminal has not moved for a certain period of time.

9. A system as claimed in claim 6, wherein:

said each mobile terminal includes a transmitter adapted to transmit at least one of voice and video data to the control console.

10. A method for monitoring movement in a three-dimensional multi-level structure, comprising:

deploying a plurality of mobile wireless remote terminals in the three-dimensional structure, each of the mobile wireless remote terminals being adapted to communicate in a wireless ad-hoc peer-to-peer communication network;

deploying a plurality of wireless routers in the three-dimensional structure, each of the wireless routers being adapted to communicate in the wireless ad-hoc peer-to-peer communication network;

controlling each of the mobile wireless remote terminals to exchange signals with any of the routers within its broadcast range and, based on those signals, to determine its location in the three-dimensional structure.

11. A method as claimed in claim 10, wherein:

said each mobile wireless remote terminal uses time of flight (TOF) data and received signal strength indicator (RSSI) data pertaining to the signals received from said any of the routers within its broadcast range to determine its location in the three-dimensional structure.

12. A method as claimed in claim 11, wherein:

the three-dimensional structure is a building, and the router deploying step deploys the routers on respective floors of the building; and

the controlling step includes controlling said each mobile wireless remote terminal to assign respective scores to each floor based on the TOF data and RSSI data pertaining to the signals, and to determine its location as a floor on which it is present based on the scores.

13. A method as claimed in claim 12, wherein:

said each mobile terminal identifies the floor on which it is present as the floor having the lowest score.

14. A method as claimed in claim 11, wherein:

the controlling step includes controlling said each mobile wireless remote terminal to use the TOF data and the RSSI data pertaining to the signals received from the routers within a certain time proximate to a time at which it determines its location based on the TOF data and the RSSI data, and to refrain from using the TOF data and the RSSI data pertaining to the signals received prior to the certain time.

15. A method as claimed in claim 10, further comprising:

deploying a control console, adapted to receive information from the mobile terminals pertaining to their respective determined locations, and to generate a display illustrating positions of the mobile terminals in the three-dimensional location.

16. A method as claimed in claim 15, wherein:

the three-dimensional location is a building, and the routers are deployed on respective floors of the building; and

the control console is adapted to generate the display illustrating the locations of the mobile terminals on the floors of the building.

17. A method as claimed in claim 15, wherein:

said each mobile terminals includes a respective motion sensor and said each mobile terminal transmits data received from its respective motion sensor to the control console; and

the control console is adapted to generate an alarm condition identifying a particular mobile terminal if the data received from a motion sensor associated with that mobile terminal indicates that that mobile terminal has not moved for a certain period of time.

18. A method as claimed in claim 15, wherein:

said each mobile terminal includes a transmitter adapted to transmit at least one of voice and video data to the control console.

19. A method as claimed in claim 10, wherein:

the router deploying step deploys the routers in the three-dimensional structure before the mobile terminals are deployed in the three-dimensional structure.

20. A method as claimed in claim 10, wherein:

the router deploying step deploys the routers in the three-dimensional structure while the mobile terminals are being deployed in the three-dimensional structure.