REAL-TIME NETWORK NODE LOCATION SYSTEM AND METHOD

• US 20130028131A1
• Filed: 10/08/2012
• Published: 01/31/2013
• Est. Priority Date: 03/20/2009
• Status: Active Grant

• Current Assignee: Buzby Networks, LLC
• Original Assignee: Buzby Networks, LLC
• Inventors: Platt, Nicholas E., Davidson, Erik J., Weiss, Daniel R., Weir, Erik D., Bilen, Sven G.
• Granted Patent: US 8,818,408 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: G01S 2013/466 by Trilateration, i.e. two antennas or two sensors determine separately the distance to a target, whereby with the knowledge of the baseline length, i.e. the distance between the antennas or sensors, the position data of the target is determined
• CPC Class Codes: G01S 5/0268 by deriving positions from different combinations of signals or of estimated positions in a single positioning system
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

A system for determining a position of location of a tag includes, in an embodiment: a plurality of routers each including at least one antenna; and a location engine to: (a) determine for at least one router, from signals sent by the one router and at least part of which are received by the at least one antenna of each of at least one other of the routers, an average path loss of signal strength; (b) optimize, for at least the one router, multipath parameters in a radio-frequency signal propagation equation using the average path loss for each of the at least one other of the routers and known distance between the router and each of the at least one other of the routers; and (c) determine the position of location of the tag using at least the optimized multipath parameters.

Claims

1. A system for determining a position of location of a tag, comprising:

a plurality of routers each comprising at least one antenna, the plurality of routers comprising at least three routers; and

a location engine to;

(a) determine for at least one router, from signals sent by the one router and at least part of which are received by the at least one antenna of each of at least one other of the routers, an average path loss of signal strength;

(b) optimize, for at least the one router, multipath parameters in a radio-frequency (RF) signal propagation model equation using the average path loss for each of the at least one other of the routers and known distance between the router and each of the at least one other of the routers; and

(c) determine the position of location of the tag using at least the optimized multipath parameters.

2. The system of claim 1, wherein the determination of the position of location of the tag at (c) comprises determining, from signals, sent by the tag, and at least part of which are received by the at least one antenna of each of at least any three of the routers, an average path loss of signal strength.

3. The system of claim 2, wherein the determination of the position of location of the tag at (c) further comprises using the optimized multipath parameters and the average path loss for each of the at least any three of the routers in the radio-frequency (RF) signal propagation model equation to determine distances between the tag and the at least any three of the routers.

4. The system of claim 1, wherein the optimization at (b) further comprises determining a final average error in distance between the one router and the at least one other of the routers, and wherein the determination of the position of location of the tag at (c) comprises using the final error in a probability density function.

5. The system of claim 1, the location engine further to:

(d) determine, from signals sent by the tag and at least part of which are received by the at least one antenna and further received by the at least one directional antenna of each of the at least any three of the routers, an average signal strength of the received signals by each of the at least one antenna and the at least one directional antenna; and

(e) determine an area of location of the tag using the average signal strengths.

6. The system of claim 5, wherein (e) comprises:

determining an area of location associated with each router;

determining a first ranking of the at least any three of the routers by average signal strength of the signals received by their at least one antennas;

determining a second ranking of the at least any three of the routers by increasing difference between the average signal strength of the signals received by their at least one antennas and the average signal strength of the signals received by their at least one directional antennas;

determining the overall top ranked router combined between the first ranking and the second ranking; and

determining the area of location of the tag as the area of location associated with the overall top ranked router.

7. The system of claim 6, the location engine further to:

(f) determine if the position of location of the tag is within the area of location of the tag, and if the position of location of the tag is within the area of location of the tag, then to determine the position of location of the tag to be a final position of location of the tag.

8. The system of claim 1, wherein the determined position of location of the tag at (c) is determined as a final position of location of the tag.

9. A system for determining a position of location of a tag, comprising:

a plurality of routers each comprising at least one antenna; and

a location engine to;

(a) determine for at least one router, from signals sent by the one router and at least part of which are received by the at least one antenna of each of at least one other of the routers, an average path loss of signal strength;

(b) optimize, for at least the one router, multipath parameters in a radio-frequency (RF) signal propagation model equation using the average path loss for each of the at least one other of the routers and known distance between the router and each of the at least one other of the routers; and

(c) determine the position of location of the tag using at least the optimized multipath parameters.