Method and apparatus for resolving RFID-based object traffic transactions to a single object in the presence of a plurality of objects

• US 20080191844A1
• Filed: 01/24/2008
• Published: 08/14/2008
• Est. Priority Date: 12/10/2003
• Status: Active Grant

• Current Assignee: Identec Solutions AG
• Original Assignee: Barry Allen, Christopher Adamson, David Lambacher
• Inventors: Adamson, Christopher, Allen, Barry, Lambacher, David
• Granted Patent: US 8,085,132 B2
• Time in Patent Office: Days
• US Class Current: 340/10.2
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations

Abstract

A method for resolving RFID-based object traffic transactions to a single object in the presence of a plurality of objects, where the method includes the steps of: monitoring RFID object traffic transactions to a single object amongst a plurality of objects wherein the traffic transactions are between at least one RFID reader and a plurality of detected RFID tags detected by the at least one RFID reader; calculating a cumulative and weighted data set for each detected RFID tag of the RFID tags; and, comparing the data set for each detected RFID tag with the data set for other of the detected RFID tags and identifying one RFID tag of the detected RFID tags having a greatest cumulative weight calculated for its corresponding data set so as to resolve multiple detections and identifications of the detected RFID tags in the object traffic transactions to the single object.

Claims

1. A method for resolving RFID-based object traffic transactions to a single object in the presence of a plurality of objects comprising the steps of:

a) monitoring RFID object traffic transactions to a single object amongst a plurality of objects wherein said traffic transactions are between at least one RFID reader and a plurality of detected RFID tags detected by said at least one RFID reader, wherein said at least one RFID reader is chosen from the group consisting of;

a plurality of stationary RFID readers, at least one mobile RFID reader,

b) calculating a cumulative and weighted data set for each detected RFID tag of said RFID tags,

c) comparing said data set for said each detected RFID tag with said data set for other of said detected RFID tags and identifying one RFID tag of said detected RFID tags having a greatest cumulative weight calculated for its corresponding said data set so as to resolve multiple detections and identifications of said detected RFID tags in said object traffic transactions to said single object,

d) calculating a plurality of overlapping proximity zones for said single object and combining said proximity zones so as to determine a maximum overlapped area having the greatest number of overlaps of said plurality of overlapping proximity zones, wherein said maximum overlapped area coincides with an area of increased probability of location of said single object,

wherein said data set includes the following data for said each detected RFID tag;

radio frequency signal strength, an incremental count of the number of said RFID tag detections and identifications, and the corresponding clock time for each count in said incremental count,

and wherein said data is, in order of most important to least important, weighted by said signal strength, said incremental count, and said corresponding clock time.

2. The method of claim 1 wherein said single object and each of said plurality of objects have their own attention-attracting device triggered by a remote unique code transmitted remotely to said device, the method further comprising the steps of:

a) determining the unique code associated said single object,

b) setting said at least one reader to spoof the unique code of said single object,

c) within said maximum overlapped area remotely spoofing the unique code of said single object so as to trigger the attention-attracting device of said single object.

3. The method of claim 1 wherein said at least one RFID reader interrogates said RFID tags for said identification of said tags.

4. The method of claim 1 wherein said single object is a single vehicle parked in at least one array of parked vehicles.

5. The method of claim 4 wherein said at least one reader is said at least one mobile reader.

6. The method of claim 5 wherein said at least one mobile reader is a single mobile RFID tag reader.

7. The method of claim 2 wherein said single object is a single vehicle parked in at least one array of parked vehicles.

8. The method of claim 7 wherein said at least one reader is said at least one mobile reader.

9. The method of claim 8 wherein said at least one mobile reader is a single mobile RFID tag reader.

10. The method of claim 2 wherein said attention-attracting device is a vehicle alarm and wherein said alarm is remotely triggered by an alarm code unique to said single vehicle when said spoofed by said at least one reader.

11. The method of claim 9 wherein said attention-attracting device is a vehicle alarm and wherein said alarm is remotely triggered by an alarm code unique to said single vehicle when said spoofed by said at least one reader.

23. The method of claim 1 further comprising the step of identifying a location of said at least one RFID reader to facilitate a location calculation of the corresponding said plurality of detected RFID tags.

24. The method of claim 23 wherein said step of identifying a location of said at least one RFID reader includes providing in said at least one RFID reader means for cooperating with said global positioning system whereby a user is provided with said location of said at least one RFID reader by the global positioning system.

25. The method of claim 24 further comprising the step of applying a correction factor to reduce a location error in said location calculation.

26. The method of claim 25 further comprising the step of calculating said correction factor by determining when one of said at least one RFID readers is in close proximity to one of said plurality of detected RFID tags, determining corresponding location error in said location provided by the global positioning system, applying a correction of said location error to all said location calculations of said plurality of detected RFID tags.

12. A system for resolving RFID-based object traffic transactions to a single object in the presence of a plurality of objects comprising:

a) at least one RFID reader and a plurality of RFID tags detectable by said at least one RFID reader,

b) means for monitoring RFID object traffic transactions to a single object amongst a plurality of objects wherein said traffic transactions are between at least one RFID reader and a plurality of detected RFID tags detected by said at least one RFID reader, wherein said at least one RFID reader is chosen from the group consisting of;

a plurality of stationary RFID readers, at least one mobile RFID reader,

c) processor means for calculating a cumulative and weighted data set for each detected RFID tag of said RFID tags,

d) processor means for comparing said data set for said each detected RFID tag with said data set for other of said detected RFID tags and identifying one RFID tag of said detected RFID tags having a greatest cumulative weight calculated for its corresponding said data set so as to resolve multiple detections and identifications of said detected RFID tags in said object traffic transactions to said single object,

e) calculating a plurality of overlapping proximity zones for said single object and combining said proximity zones so as to determine a maximum overlapped area having the greatest number of overlaps of said plurality of overlapping proximity zones, wherein said maximum overlapped area coincides with an area of increased probability of location of said single object,

wherein said data set includes the following data for said each detected RFID tag;

radio frequency signal strength, an incremental count of the number of said RFID tag detections and identifications, and the corresponding clock time for each count in said incremental count,

and wherein said data is, in order of most important to least important, weighted by said signal strength, said incremental count, and said corresponding clock time.

13. The system of claim 12 wherein said single object and each of said plurality of objects have their own attention-attracting device triggered by a remote unique code transmitted remotely to said device, the method further comprising the steps of:

a) determining the unique code associated said single object,

b) setting said at least one reader to spoof the unique code of said single object,

c) within said maximum overlapped area remotely spoofing the unique code of said single object so as to trigger the attention-attracting device of said single object.

14. The system of claim 12 wherein said single object is a single vehicle parked in at least one array of parked vehicles.

15. The system of claim 14 wherein said at least one reader is said at least one mobile reader.

16. The system of claim 15 wherein said at least one mobile reader is a single mobile RFID tag reader.

17. The system of claim 13 wherein said single object is a single vehicle parked in at least one array of parked vehicles.

18. The system of claim 17 wherein said at least one reader is said at least one mobile reader.

19. The system of claim 18 wherein said at least one mobile reader is a single mobile RFID tag reader.

20. The system of claim 13 wherein said attention-attracting device is a vehicle alarm and wherein said alarm is remotely triggered by an alarm code unique to said single vehicle when said spoofed by said at least one reader.

21. The system of claim 19 wherein said attention-attracting device is a vehicle alarm and wherein said alarm is remotely triggered by an alarm code unique to said single vehicle when said spoofed by said at least one reader.

22. The system of claim 12 wherein said at least one RFID reader interrogates said RFID tags for said identification of said tags.

27. The system of claim 12 further comprising means for identifying a location of said at least one RFID reader to facilitate a location calculation of the corresponding said plurality of detected RFID tags.

28. The system of claim 27 wherein said means for identifying a location of said at least one RFID reader includes means for cooperating with said global positioning system whereby a user is provided with said location of said at least one RFID reader by the global positioning system.

29. The system of claim 28 further comprising means for applying a correction factor to reduce a location error in said location calculation.

30. The system of claim 29 further comprising means for calculating said correction factor by determining when one of said at least one RFID readers is in close proximity to one of said plurality of detected RFID tags, determining corresponding location error in said location provided by the global positioning system, and applying a correction of said location error to all said location calculations of said plurality of detected RFID tags.