System and method of reading from and/or writing to an RF transponder

• US 20060273883A1
• Filed: 06/06/2005
• Published: 12/07/2006
• Est. Priority Date: 06/06/2005
• Status: Active Grant

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Martinez, Rene, Heinrich, Harley, Pillai, Vijay
• Granted Patent: US 7,501,932 B2
• Time in Patent Office: Days
• US Class Current: 340/10.420
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

At least one identification (ID) number is used to effectuate communication between a radio frequency (RF) number and a radio frequency identification (RFID) base station. In accordance with a first embodiment of the present invention, at least a `first ID number and a second ID number are stored on an RF transponder. Upon receipt of a write request, the RF transponder compares an ID number portion of the write request with the second ID number stored on the RF transponder. If the numbers matched, then a data portion of the write request is stored on the RF transponder. If the ID numbers do not match, then the write request is ignored. In accordance with a second embodiment of the present invention, the RF transponder is adapted to determine the second ID number using at least a portion of the first ID number. For example, the second ID number could be a subset of the first ID number, determined using an algorithm that is based (at least in part) on a portion of the first ID number, etc. In accordance with a third embodiment of the present invention, the second ID number is independent of the first ID number. For example, the second ID number could be a constant that is unrelated to the first ID number. In accordance with a fourth embodiment of the present invention, the data portion of the write request is stored on the RF transponder before the ID number portion of the write request is compared to the ID number stored on the RF transponder. If the ID number portion of the write request matches the ID number stored on the RF transponder, then the stored data is left undisturbed. If, however, the ID numbers do not match, then the stored data is erased (e.g., replaced with a null set, the original data, etc.).

Claims

1. A radio frequency identification (RFID) system comprising:

a radio frequency (RF) transponder and a RFID base station, said RF transponder comprising;

a front end circuit adapted to receive and transmit RF signals;

an antenna electrically connected to said front end circuit;

a signal processing circuit electrically connected to said front end circuit and adapted to decode received RF signals; and

a memory for storing first and second identification (ID) numbers, said first ID number being a substantially unique identifier of said RF transponder and said second ID number being smaller than said first ID number, usable to distinguish said RF transponder from at least one other RF transponder, and at least partially based on said first ID number.

2. The RFID system of claim 1, wherein said RFID base station comprises:

a communication circuit adapted to receive and transmit RF signals; and

a processor adapted to acquire said second ID number and to transmit a write data packet to said RF transponder, said write data packet including at least said second ID number and data to be stored in said memory.

3. The RFID system of claim 1, wherein said memory includes at least one register.

4. The RFID system of claim 1, wherein said first ID number is a unique identifier.

5. The RFID system of claim 1, wherein said first ID number includes a string of identification numbers.

6. The RFID system of claim 1, wherein said second ID number is a subset of said first ID number.

7. The RFID system of claim 1, wherein said second ID number is a product of a random-number-generator algorithm that uses a least a portion of the first ID number as a seed.

8. The RFID system of claim 1, wherein said memory comprises a write protected sector and an unprotected sector, wherein said first and second ID numbers are stored in said write protected sector of said memory.

9. The RFID system of claim 1, wherein said memory comprises a write protected sector and an unprotected sector, said first ID number being stored in said write protected sector of said memory and said second ID number being stored in said unprotected sector of said memory.

10. The RFID system of claim 1, wherein said signal processing circuit is further adapted to:

acknowledge a received write data packet as a write request, said write data packet including at least data, an address, and an ID number;

store said data at said address in said memory; and

compare said ID number with said second ID number and erase said data from said memory if said ID number does not match said second ID number.

11. The RFID system of claim 10, wherein said signal processing circuit is further adapted to erase said data from said memory if said ID number does not match said second ID number by replacing said data with original data, said original data being stored at said address prior to said step of storing said data at said address in said memory.

12. The RFID system of claim 10, wherein said signal processing circuit is further adapted to erase said data from said memory if said ID number does not match said second ID number by replacing said data with a null set of data.

13. The RFID system of claim 10, wherein said signal processing circuit is further adapted to store a portion of said data at substantially the same time as said portion is received by said signal processing circuit.

14. A radio frequency (RF) transponder comprising:

a front end circuit adapted to receive and transmit RF signals;

an antenna electrically connected to said front end circuit;

a memory device for storing at least one identification (ID) number; and

a signal processing circuit electrically connected to said front end and said memory device, said signal processing circuit being adapted to;

recognize an incoming RF signal as a write request, said write request including at least data, an address, and a transponder identifier;

store said data at said address in said memory; and

compare said transponder identifier with at least a portion of said at least one ID number and erase said data from said memory if said transponder identifier does not match said at least a portion of said at least one ID number.

15. The RF transponder of claim 14, wherein said signal processing circuit is further adapted to store a portion of said data at substantially the same time as said portion is received by said signal processing circuit.

16. The RF transponder of claim 14, wherein said signal processing circuit is further adapted to store at least a portion of said data before the entire portion of said transponder identifier is received by said signal processing circuit.

17. The RF transponder of claim 14, wherein said memory device further stores a first ID number and a second ID number and said signal processing circuit is further adapted to compare said transponder identifier with said first ID number and erase said data from said memory if said transponder identifier does not match said first ID number.

18. The RF transponder of claim 14, wherein said memory device further stores a first ID number and a second ID number and said signal processing circuit is further adapted to compare said transponder identifier with said second ID number and erase said data from said memory if said transponder identifier does not match said second ID number.

19. The RF transponder of claim 18, wherein said second ID number is based on said first ID number

20. The RF transponder of claim 18, wherein said second ID number is a subset of said first ID number.

21. The RF transponder of claim 18, wherein said second ID number is a product of a random-number-generator algorithm that uses at least a portion of said first ID number as a seed.

22. The RF transponder of claim 18, wherein said first ID number is a unique identifier of said RF transponder and said second ID number is smaller than said first ID number and usable to distinguish said RF transponder from at least one other RF transponder.

23. A method of communicating with an radio frequency identification (RFID) base station, comprising:

receiving a request to store data in a memory device on a radio frequency (RF) transponder, said request including at least said data and a transponder identifier; and

comparing said transponder identifier to a second identification (ID) number to determine whether said data should be stored in said memory device, said second ID number being;

generated using at least a portion of a first ID number, said first ID number being a substantially unique identifier of said RF transponder; and

usable to distinguish said RF transponder from at least one other RF transponder.

24. The method of claim 23, wherein said second ID number is smaller than said first ID number.

25. The method of claim 23, further comprising the steps of retrieving at least one of said second ID number and said first ID number from memory.

26. The method of claim 25, further comprising the steps of retrieving at least one of said second ID number and said first ID number from combinatorial logic.

27. The method of claim 23, further comprising the steps of:

receiving a request for at least said second ID number from said RFID base station; and

backscattering at least said second ID number to said RFID base station.

28. The method of claim 23, further comprising the step of storing said data in said memory device if said transponder identifier matches said second ID number.

29. The method of claim 23, further comprising the step of storing at least a portion of said data in said memory device and erasing said at least a portion of said data from said memory device if said transponder identifier does not match said second ID number.

30. The method of claim 23, wherein said second ID number is a subset of said first ID number.

31. The method of claim 23, wherein said second ID number is derived from said first ID number.

32. The method of claim 23, wherein said second ID number is generated using an algorithm that is based on at least a portion of said first ID number.

33. The method of claim 23, wherein said second ID number is stored in said memory device during the manufacturing of said RF transponder.

34. The method of claim 23, wherein said second ID number is determined by said RF transponder and after said RF transponder is manufactured.

35. The method of claim 23, wherein said second ID number is assigned by said RFID base station.

36. A radio frequency identification (RFID) system comprising:

a radio frequency (RF) transponder and a RFID base station, said RF transponder comprising;

a front end circuit adapted to receive and transmit RF signals;

an antenna electrically connected to said front end circuit;

a signal processing circuit electrically connected to said front end circuit and adapted to decode received RF signals; and

a memory for storing first and second identification (ID) numbers, said first ID number being a substantially unique identifier of said RF transponder and said second ID number being smaller than said first ID number, usable to distinguish said RF transponder from at least one other RF transponder, a constant, and independent from said first ID number.