System and method for tracking in multi-story buildings

• US 9,053,624 B2
• Filed: 01/17/2012
• Issued: 06/09/2015
• Est. Priority Date: 01/17/2012
• Status: Active Grant

• Current Assignee: Extreme Networks, Inc.
• Original Assignee: Avaya Incorporated
• Inventors: Bentley, Jon L., Krishnakumar, Anjur S., Yajnik, Shalini
• Primary Examiner(s): Wang, Jack K
• Application Number:
  US13/351,451
• Publication Number:
  US 20130181834A1
• Time in Patent Office: 1,239 Days
• Field of Search: 340/539.13, 340/665, 340/572.8, 455/435.2, 342/451
• US Class Current: 1/1
• CPC Class Codes: G08B 13/2462 Asset location systems combined with EAS inventory, tracking, logistic G06Q10/00; entrance control systems G07C9/00
• CPC Class Codes: G08B 21/0252 System arrangements wherein the child unit emits, i.e. the child unit incorporates the emitter
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings

Abstract

System and method to locate a person in a multi-level building, including: a portable transmitter coupled to the person, the portable transmitter configured to transmit a signal comprising an identification code; a plurality of receivers located in a multi-level building to receive the signal, substantially each receiver producing a received signal, wherein at least a first receiver is located on a first level and at least a second receiver is located on a second level, wherein the second level is different than the first level; a signal strength estimator coupled to at least one receiver, the signal strength estimator configured to produce a signal strength estimation of the received signal received by the at least one receiver; and a processor configured to receive the signal strength estimations, and from the signal strength estimations calculate a level of the multi-level building on which the person is located.

Claims

1. A portable transponder to locate a person in a multi-level building, comprising:

a first communication module configured to communicate with a plurality of WiFi transceivers located in a multi-level building after the plurality of WiFi transceivers have been switched from a normal operating mode of a WiFi network to an emergency tracking mode of the WiFi network based on a signal indicating an emergency, wherein at least a first WiFi transceiver is located on a first level and at least a second WiFi transceiver is located on a second level, wherein the second level is different than the first level; and

a processing module coupled to a memory, the processing module configured to process signal identifying the person communicated via the first communication module.

2. The portable transponder of claim 1, wherein the first communication module comprises a transmitter, and wherein the processing module is configured to process an identification of the portable transponder.

3. The portable transponder of claim 1, further comprising:

a second communication module configured to wirelessly communicate with a control module,

wherein the second communication module comprises a receiver configured to receive individually identifiable signals transmitted by the WiFi transceivers,

wherein each received individually identifiable signal includes an identification of the WiFi transceiver,

wherein the portable transponder transmits an identification of the received individually identifiable signals and a characteristic of the received individually identifiable signals via the second communication module.

4. The portable transponder of claim 1, wherein the portable transponder is coupled to a person.

5. The portable transponder of claim 1, wherein the portable transponder comprises an emergency signal activator.

6. The portable transponder of claim 5, wherein the emergency signal activator comprises a voice recognition module.

7. The portable transponder of claim 5, wherein the emergency signal activator comprises an acoustic processing module to detect an audible emergency signal from another portable transponder.

8. A system to locate a person in a multi-level building, comprising:

a portable transmitter coupled to the person, the portable transmitter configured to transmit a signal comprising an identification code for identifying the person;

a WiFi network comprising a plurality of WiFi receivers located in a multi-level building to receive the signal, substantially each WiFi receiver producing a received signal, wherein at least a first WiFi receiver is located on a first level and at least a second WiFi receiver is located on a second level, wherein the second level is different than the first level;

an access port configured to switch the WiFi network between a normal operating mode of the WiFi network and an emergency operating mode of the WiFi network, based on a signal indicating an emergency;

a signal strength estimator coupled to at least one WiFi receiver, the signal strength estimator configured to produce a signal strength estimation of the received signal received by the at least one WiFi receiver; and

a processor configured to receive the signal strength estimations and identification code, and calculate a level of the multi-level building on which the person is located based on the signal strength estimations and the identification code.

9. The system of claim 8, further comprising a memory coupled to the processor, the memory configured to store instructions such that, when the instructions are performed by the processor, the processor performs the steps of:

ranking the received signals received at various strengths in the order of strength;

considering the m strongest received signals to be a first subset, where m is a positive integer;

when a majority of the m strongest received signals of the first subset are associated with a same zone, considering that same zone to be a candidate zone;

adding a value k to the strongest received signal not in the first subset, which may or may not change the ranking of the received signals received at various strengths in the order of strength;

considering the m strongest received signals to be a second subset; and

when a majority of the m strongest received signals of the second subset are associated with a same zone, determining whether that same zone matches the candidate zone, and if so, determining the portable transmitter to be located in the candidate zone.

10. The system of claim 8, wherein the processor is configured to allow external access and control.

11. The system of claim 8, wherein the access port further comprises a physical access port.

12. A method to locate a person in a multi-level building, comprising:

switching a WiFi communication system from a normal WiFi operating mode to an emergency WiFi tracking mode by use of an access port based on a signal indicating an emergency, wherein the WiFi communication system comprises a plurality of WiFi receivers located in the multi-level building;

transmitting a signal comprising an identification code for identifying the person by use of a portable transmitter coupled to the person;

receiving the signal by the plurality of WiFi receivers located in the multi-level building, substantially each WiFi receiver producing a received signal, wherein at least a first WiFi receiver is located on a first level and at least a second WiFi receiver is located on a second level, wherein the second level is different than the first level;

producing a signal strength estimation of the received signal received by the at least one WiFi receiver by use of a signal strength estimator coupled to the at least one WiFi receiver; and

calculating a level of the multi-level building on which the person is located by use of a processor configured to receive the signal strength estimations and the identification code.

13. The method of claim 12, further comprising:

ranking the received signals received at various strengths in the order of strength;

considering the m strongest received signals to be a first subset, where m is a positive integer;

when a majority of the m strongest received signals of the first subset are associated with a same zone, considering that same zone to be a candidate zone;

adding a value k to the strongest received signal not in the first subset, which may or may not change the ranking of the received signals received at various strengths in the order of strength;

considering the m strongest received signals to be a second subset; and

when a majority of the m strongest received signals of the second subset are associated with a same zone, determining whether that same zone matches the candidate zone, and if so, determining the portable transmitter to be located in the candidate zone.

14. The method of claim 12, wherein the portable transmitter is coupled to the clothing of the person.

15. The method of claim 12, wherein the processor is configured to allow external access and control.

16. The method of claim 12, wherein the access port comprises a physical access port.

17. The method of claim 12, wherein the portable transmitter comprises an emergency signal activator.

18. The method of claim 17, wherein the emergency signal activator comprises a voice recognition module.

19. The method of claim 17, wherein the emergency signal activator comprises an acoustic processing module to detect an audible emergency signal from another portable transmitter.