IDENTIFICATION OF OBJECTS USING FREQUENCY CHARACTERISTICS OF RFID TAGS

• US 20110133903A1
• Filed: 12/09/2008
• Published: 06/09/2011
• Est. Priority Date: 12/19/2007
• Status: Active Grant

• Current Assignee: Beijing Xiaomi Mobile Software Co., Ltd. (Xiaomi Corp.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Alsafadi, Yasser
• Granted Patent: US 9,818,053 B2
• Time in Patent Office: Days
• US Class Current: 340/10.4
• 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
• CPC Class Codes: G06K 19/0672 with resonating marks
• CPC Class Codes: G06K 19/0724 the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
• CPC Class Codes: G06K 7/10069 the collision being resolved in the frequency domain, e.g. by hopping from one frequency to the other frequency hopping or spread spectrum techniques H04B7/00

Abstract

An apparatus that identifies an object includes a frequency detector (112) that detects a frequency over which an RFID tag (102) communicates, and an object identifier (120) that identifies the object based at least in part upon the detected frequency. The frequency detector may detect a plurality of frequencies over which a plurality of RFID tags transmit information. The apparatus also optionally includes a frequency pattern generator that generates a frequency pattern that is indicative of an identity of the object, wherein the object identifier compares the generated frequency pattern with known frequency patterns to determine the identity of the object.

Claims

1. An apparatus that identifies an object, comprising:

a frequency detector that detects a frequency over which an RFID tag communicates; and

an object identifier that identifies the object based at least in part upon the detected frequency.

2. The apparatus of claim 1, wherein the frequency detector detects a plurality of frequencies used by a plurality of RFID tags to transmit information, and further comprising:

a frequency pattern generator that generates a frequency pattern that is indicative of an identity of the object, wherein the object identifier compares the generated frequency pattern with known frequency patterns to determine the identity of the object.

3. The apparatus of claim 2, wherein the frequency pattern has the general form {Af1;

Bf2;

. . . Xfn}, where A, B, and X are integers that indicate a number of RFID tags that transmit information over frequencies f, and n is a number of frequencies detected.

4. The apparatus of claim 2, further comprising a context analyzer that outputs a context that corresponds to the object, wherein the object identifier determines the identity of the object based at least in part upon the output context.

5. The apparatus of claim 1, further comprising an RFID reader that outputs radio signals that power the RFID tag.

6. The apparatus of claim 5, wherein the RFID reader reads an identification of the RFID tag and the object identifier identifies the object based at least in part upon the detected frequency and the identification of the RFID tag.

7. The apparatus of claim 5, wherein the RFID reader reads content of memory of the RFID tag and the object identifier identifies the object based at least in part upon the detected frequency and the content of memory of the RFID tag.

8. The apparatus of claim 1, wherein the object is one of an intangible object, a healthcare object, an industrial object, or a retail object.

10. The apparatus of claim 1 being an inventory-tracking apparatus.

11. A method for identifying an object, comprising:

detecting a frequency over which an RFID tag communicates; and

identifying the object based at least in part upon the detected frequency.

12. The method of claim 11, further comprising:

performing a frequency sweep over a frequency range;

detecting a plurality of frequencies over which a plurality of RFID tags communicate; and

identifying the object based at least in part upon the plurality of detected frequencies.

13. The method of claim 12, further comprising:

determining a number of RFID tags that communicate over each of the detected frequencies;

preparing a frequency pattern that comprises a list of the detected frequencies and the number of RFID tags that communicate over each of the detected frequencies;

comparing the frequency pattern with known frequency patterns; and

identifying the object based at least in part upon the comparison.

14. The method of claim 11, wherein the RFID tag is a spectrum agile radio RFID tag.

15. The method of claim 11, further comprising:

receiving an identity of the RFID tag; and

identifying the object based at least in part upon the detected frequency and the received identity.

16. The method of claim 11, further comprising:

receiving content from a memory of the RFID tag; and

identifying the object based at least in part upon the detected frequency and the received content.

17. The method of claim 11, wherein the object corresponds to a healthcare environment.

18. The method of claim 11, further comprising identifying the object based at least in part upon a defined context.

19. The method of claim 18, wherein the context is defined to identify tangible or intangible objects desirably identified by a regulating body.

20. The method of claim 18, wherein the context is defined based at least in part upon a current security setting or based at least in part upon current weather conditions.

21. The method of claim 11, wherein the RFID tag is one of a passive RFID tag, an active RFID tag, and a semi-active RFID tag.

22. The method of claim 11, further comprising providing an identity of the object to a hospital information system.

23. The method of claim 11, further comprising providing an identity of the object to a radiology information system.

24. A computer-readable medium comprising instructions that, when executed by a processor, perform the following acts:

performing a frequency sweep for spectral agile radio RFID tags;

preparing a list of detected spectral agile radio RFID tags based at least in part upon frequencies detected during the frequency scan;

constructing a list of potential objects based at least in part upon the detected frequencies; and

constructing a list of identified objects based at least in part upon a context assigned to the spectral agile radio RFID tags.

25. A data repository, comprising:

frequency patterns that correspond to a plurality of objects, wherein an object is identified by comparing an observed frequency pattern with at least a subset of the frequency patterns in the data repository.