MOBILE DEVICE LOCATION SYSTEM FOR WIRELESS E911 SERVICES

• US 20100048163A1
• Filed: 08/20/2008
• Published: 02/25/2010
• Est. Priority Date: 08/20/2008
• Status: Abandoned Application

• Current Assignee: Dianet Communications, Inc.
• Original Assignee: Dianet Communications, Inc.
• Inventors: Parr, Mark H., Julius, Arthur A.
• Application Number:
  US12/194,719
• Publication Number:
  US 20100048163A1
• Time in Patent Office: Days
• US Class Current: 455/404.200
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• 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 76/50 for emergency connections

Abstract

Disclosed are systems and methods for locating a mobile telecommunication device within a building or underground facility. The system operates by receiving over a telecommunication network an emergency transmission from a mobile telecommunication device located within the facility. The system then determines propagation time delay of the received emergency transmission and identifies two or more RF nodes located within the facility in the proximity of the mobile device based on the determined propagation time delay. The system then sends a request to the identified RF nodes to perform signal strength measurements on the mobile telecommunication device. The system then compares the signal strength measurements of the RF nodes to estimate the approximate location coordinates of the mobile telecommunication device relative to the RF nodes within the facility.

Claims

1. A method for locating a mobile telecommunication device within a building or underground facility, the method comprising:

receiving over a telecommunication network an emergency transmission from a mobile telecommunication device located within the facility;

determining propagation time delay of the received emergency transmission;

based on the determined propagation time delay, identifying two or more RF nodes located within the facility in the proximity of the mobile device;

sending a request to the identified RF nodes to perform signal strength measurements on the mobile telecommunication device; and

comparing the signal strength measurements of the RF nodes to estimate the approximate location coordinates of the mobile telecommunication device relative to the RF nodes within the facility.

2. The method of claim 1 further comprising reporting the location coordinates of the mobile telecommunication device to the nearest public safety office.

3. The method of claim 1, wherein the emergency transmission includes a 911 call.

4. The method of claim 1, wherein detecting an emergency transmission from a mobile telecommunication device includes detecting activity on the designated emergency wireless channel at a RF node.

5. The method of claim 1, wherein the telecommunication network includes at least one of a wireless network segment and at least one wired network segment.

6. The method of claim 5, where in the propagation time delay is computed over the one or more wired network segments.

7. The method of claim 1 further comprising using a look-up table of the RF nodes and the corresponding propagation time delays between each RF node and a remote data processing node to identifying two or more RF nodes located in the proximity of the mobile telecommunication device.

8. A system for locating a mobile telecommunication device in a building or underground facility, the system comprising:

one or more RF nodes located within the facility, each RF node having one or more RF antennas distributed within the facility, wherein a RF node is configured to receive an emergency wireless transmission from a mobile telecommunication device located within the facility, and

a remote data processing node connected to the one or more RF nodes via a wired telecommunication network, the data processing node being configured to

(i) receive from a RF node the emergency transmission from a mobile telecommunication device, and

(ii) determine location of the mobile telecommunication device within the facility based on the propagation time delay of the emergency transmission over the wired telecommunication network and signal strength measurements of two or more RF nodes located in the proximity of the mobile device.

9. The system of claim 8, wherein the data processing node is further configured to report the location coordinates of the mobile telecommunication device to the nearest public safety office.

10. The system of claim 8, wherein the emergency wireless transmission includes a 911 call.

11. The system of claim 8, wherein the emergency transmission includes a transmission on a designated emergency wireless channel.

12. The system of claim 8, wherein the wired telecommunication network includes a fiber optic telecommunication network.

13. The system of claim 8, wherein the wireless telecommunication network includes a cellular network.

14. The system of claim 8, wherein the data processing node uses a look-up table of the RF nodes and the corresponding propagation time delays between the RF node and a remote data processing node to identifying two or more RF nodes located in the proximity of the mobile telecommunication device.

15. A method for locating a mobile telecommunication device in a building or underground facility, the method comprising:

providing within the facility one or more RF nodes, each RF node having one or more RF antennas associated therewith, wherein a RF node is configured to receive an emergency wireless transmission from a mobile telecommunication device located within the facility; and

providing a remote data processing node connected to the one or more RF nodes via a wired telecommunication network, the data processing node being configured to

(i) receive from a RF node the emergency transmission from a mobile telecommunication device located within the facility and

(ii) determine location of the mobile telecommunication device within the facility based on the propagation time delay of the emergency transmission over the wired telecommunication network and signal strength measurements of two or more RF nodes located in the proximity of the mobile device.

16. The method of claim 15 wherein the data processing node is configured to report the location coordinates of the mobile telecommunication device to the nearest public safety office.

17. The method of claim 15, wherein the emergency wireless transmission includes a 911 call.

18. The method of claim 15, wherein the emergency wireless transmission includes a transmission on a designated emergency wireless channel.

19. The method of claim 15, wherein the wired telecommunication network includes a fiber optic telecommunication network.

20. The method of claim 15, wherein the wireless telecommunication network includes a cellular network.

21. The method of claim 15, wherein the data processing node uses a look-up table of the RF nodes and the corresponding propagation time delays between the RF node and the data processing node to identifying two or more RF nodes located in the proximity of the mobile telecommunication device.

22. A RF node located in a building or underground facility, the RF node comprising:

one or more RF antennas distributed within the facility;

a first RF receiver coupled to the one or more RF antennas, the first RF transceiver being configured to receive an emergency wireless transmission from a mobile telecommunication device located within the facility;

a second RF receiver coupled to the one or more RF antennas, the second RF transceiver being configured to measure signal strength of the mobile telecommunication device sending the emergency wireless transmission;

a processor configured to convert the wireless transmission into optical signals;

a fiber optic transmitter configured to send the converted optical signals to a remote data processing node over a fiber optic telecommunication network.

23. The base station of claim 22, wherein the emergency wireless transmission includes a 911 call.

24. The base stations of claim 22, wherein the emergency transmission includes a transmission on a designated emergency wireless channel.

25. The base station of claim 22, wherein the wireless telecommunication network includes a cellular network.