System and Method for Mobile Location By Proximity Detection

• US 20110171912A1
• Filed: 01/07/2011
• Published: 07/14/2011
• Est. Priority Date: 01/08/2010
• Status: Active Grant

• Current Assignee: Bison Patent Licensing, LLC
• Original Assignee: Andrew LLC (CommScope Holding Company, Inc.)
• Inventors: Gravely, Thomas B., Beck, Andrew
• Granted Patent: US 9,331,798 B2
• Time in Patent Office: Days
• US Class Current: 455/67.11
• CPC Class Codes: G01S 5/02213 Receivers arranged in a network for determining the position of a transmitter
• CPC Class Codes: H04B 17/26 using historical data, averaging values or statistics
• CPC Class Codes: H04B 17/27 for locating or positioning the transmitter
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/327 Received signal code power [RSCP]
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 17/364 Delay profiles

Abstract

A system and method for determining the location of a mobile device in a communications network having one or more proximity sensors. A request to locate the mobile device may be received and at least one of the proximity sensors tasked to receive a signal transmission from the mobile device. One or more signal characteristics of the signal transmission from the mobile device may be measured by each tasked proximity sensor, and a location of the mobile device determined as a function of the measured characteristics. This may be accomplished by associating a fixed location with each tasked proximity sensor, and then determining the location of the mobile device as a function of one of the associated fixed locations.

Claims

1. A method of determining the location of a mobile device in a communications network having one or more proximity sensors, the method comprising the steps of:

(a) receiving a request to locate the mobile device;

(b) tasking at least one of the proximity sensors to receive a signal transmission from the mobile device;

(c) measuring one or more signal characteristics of the signal transmission from the mobile device by each tasked proximity sensor; and

(d) determining a location of the mobile device as a function of the measured characteristics by;

(i) associating a fixed location with each tasked proximity sensor, and

(ii) determining the location of the mobile device as a function of one of the associated fixed locations.

2. The method of claim 1 wherein the fixed location is selected from the group consisting of a centroid of signal coverage for the proximity sensor, a most probable location determined as a function of proximity sensor surroundings, and a location determined as a function of physical boundaries around the proximity sensor limiting possible locations of the mobile device.

3. The method of claim 1 wherein step (ii) further comprises:

(ii) determining the location of the mobile device as a function of a straight average of the associated fixed locations.

4. The method of claim 1 wherein step (ii) further comprises:

(ii) determining the location of the mobile device as a function of a weighted average of the associated fixed locations.

5. The method of claim 1 wherein step (ii) further comprises:

(ii) determining the location of the mobile device as a function of a weighted average and a straight average of the associated fixed locations.

6. The method of claim 1 wherein the request is provided by the mobile device.

7. The method of claim 1 wherein the request is a tasking message provided by the network or by a scanning receiver proximate to the mobile device.

8. The method of claim 1 wherein the proximity sensor is embedded in a repeater in the network, in a component of a distributed antenna system of the network, in a core component of the network, and combinations thereof.

9. The method of claim 1 wherein the proximity sensor is connected to a repeater in the network, to a component of a distributed antenna system of the network, to a core component of the network, and combinations thereof.

10. The method of claim 1 wherein the proximity sensor is an independent, standalone receiver apparatus.

11. The method of claim 1 wherein the step of measuring further comprises:

(i) utilizing a radio frequency (RF) signal parameter of the signal transmission from the mobile device, and

(ii) determining metrics on the signal transmission from the mobile device.

12. The method of claim 11 wherein the RF signal parameter is selected from the group consisting of channel number, channel frequency, timeslot, network timing information, range information, spreading code, and combinations thereof.

13. The method of claim 11 wherein the metric is selected from the group consisting of received signal strength indication, signal to noise ratio, ratio of energy per bit over power spectral density of noise and interference (Eb/Io), ratio of received pilot energy over power spectral density of noise and interference (Ec/Io), and combinations thereof.

14. The method of claim 1 further comprising the step of determining a quality metric to judge an accuracy of the determined location of the mobile device.

15. In a method for determining a location of a mobile device in a communications network having a plurality of base station transceivers in communication with the mobile device, the improvement comprising determining the location of the mobile device without utilizing signals transmitted from the base station transceivers by using proximity detection sensors deployed in the network and by determining the location of the mobile device as a function of information provided by ones of the proximity detection sensors.

16. The method of claim 15 wherein the step of determining the location of the mobile device as a function of information provided by the proximity detection sensors further comprises:

tasking at least one of the proximity sensors to receive a signal transmission from the mobile device;

measuring one or more signal characteristics of the signal transmission from the mobile device by each tasked proximity sensor;

associating a fixed location with each tasked proximity sensor;

determining the location of the mobile device as a function of one of the associated fixed locations.

17. A method of determining the location of a mobile device in a communications network having one or more proximity sensors, the method comprising the steps of:

(a) receiving a request to locate the mobile device;

(b) tasking at least one of the proximity sensors to receive a signal transmission from the mobile device;

(c) measuring one or more signal characteristics of the signal transmission from the mobile device by each tasked proximity sensor; and

(d) determining a location of the mobile device as a function of the measured characteristic,

wherein the measured characteristic includes range information.

18. The method of claim 17 wherein the step of measuring further comprises:

(i) measuring by each tasked proximity sensor a transmit time of a signal transmitted from a base station transceiver, repeater or antenna,

(ii) compensating by the proximity sensor for a receive time of the signal transmitted from the base station transceiver, repeater or antenna,

(iii) compensating for transceiver processing delay of the mobile device, and

(iv) determining flight time of the signal transmission from the mobile device as a function of the measured transmit time, the compensated receive time and compensated delay.

19. The method of claim 17 wherein the step of measuring further comprises:

(i) receiving transmit time information of a signal transmitted from a base station transceiver, repeater or antenna,

(ii) compensating for a receive time of the signal transmitted from the base station transceiver, repeater or antenna,

(iii) compensating for transceiver processing delay of the mobile device, and

(iv) determining flight time of the signal transmission from the mobile device as a function of the received transmit time information, the compensated receive time and compensated delay.

20. A method of determining if a mobile device is operating in a predetermined region of a communications network comprising the steps of:

(a) receiving a request to locate the mobile device;

(b) tasking one or more proximity sensors in the network to receive a signal transmission from the mobile device;

(c) measuring one or more signal characteristics of the signal transmission from the mobile device by the tasked proximity sensor;

(d) associating a fixed location with each tasked proximity sensor; and

(e) determining the proximity of the mobile device in the predetermined region using the associated fixed locations.