Systems and methods for secure supply chain management and inventory control

• US 8,174,369 B2
• Filed: 11/29/2007
• Issued: 05/08/2012
• Est. Priority Date: 10/08/2007
• Status: Expired due to Fees

• Current Assignee: Mojix Inc
• Original Assignee: Mojix Inc
• Inventors: Jones, Christopher Richard, Sadr, Ramin
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): GIRMA, FEKADESELASS
• Application Number:
  US11/947,474
• Publication Number:
  US 20090091451A1
• Time in Patent Office: 1,622 Days
• Field of Search: None
• US Class Current: 340/10.52
• 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

Systems for encoding and reading RFID tags on a collection of items are shown. One embodiment of the invention includes a plurality of items, where each item possesses an item identifier string, and a plurality of RFID tags, where an RFID tag is affixed to each of the items and each RFID tag is encoded with a code word element generated using at least all of the item identifier strings. In many embodiments, the collection is a plurality of goods contained within a case, pallet, container or storage area.

Claims

1. A collection, comprising:

a plurality of items, where each item possesses an item identifier string; and

a plurality of RFID tags, where an RFID tag is affixed to each of the items and each RFID tag is encoded with a code word element generated using at least all of the item identifier strings,

wherein the items are not identifiable by reading an individual RFID tag affixed to the item, and

wherein the combination of code word elements from a subset of the RFID tags contains information indicative of all of the item identifier strings.

2. The collection of claim 1, wherein a subset of the code word elements contain information indicative of all of the item identifier strings.

3. The collection of claim 1, wherein all of the code word elements form a code word that comprises:

information indicative of all of the item identifier strings; and

error correction code.

4. The collection of claim 3, wherein the code word further comprises manifest information.

5. The collection of claim 3, wherein the information indicative of all of the item identifier strings is a compressed set of item identifier strings, where the set of item identifier strings is formed from the item identifier strings of all of the items in the collection.

6. The collection of claim 5, wherein the error correction code is derived by applying error correction coding to the information indicative of all of the item identifier strings.

7. The collection of claim 5, wherein the information indicative of all of the item identifier strings is encrypted.

8. The collection of claim 5, wherein the code word is interleaved in accordance with an interleaver defined by a pseudo-random key.

9. The collection of claim 8, further comprising a collection RFID tag encoded with an encrypted copy of the pseudo-random key.

10. The collection of claim 1, wherein:

each item identifier string includes an item sequence number for the item; and

each RFID tag is encoded with the item sequence number of the item to which the RFID tag is attached in addition to the code word element.

11. The collection of claim 10, wherein:

the collection possesses a collection serial number; and

the RFID tag on each item in the collection is encoded with the collection serial number in addition to a code word element and an item sequence number.

12. The collection of claim 11, wherein each RFID tag is also encoded with information identifying the item to which the RFID tag is attached in addition to a code word element.

13. A method of producing RFID tags for identifying a collection of items, where each item is identified by an item identifier string, comprising:

creating a set of identifier strings using the item identifier strings of all of the items in the collection;

generating a code word using at least the set of identifier strings;

breaking the code word into a number of code word elements equal to the number of items in the collection;

using each code word element to encode a separate RFID tag; and

affixing the RFID tags to the collection of items so that the items are not identifiable by reading an individual RFID tag affixed to the item, and the combination of code word elements from a subset of the RFID tags contains information indicative of the set of item identifier strings.

14. The method of claim 13, wherein the code word is generated using at least the set of identifier strings and manifest information.

15. The method of claim 13, wherein generating a code word using the set of identifier strings further comprises:

compressing the set of identifier strings; and

adding error correction code to the compressed set of item identifier strings.

16. The method of claim 15, wherein generating a code word using the set of identifier strings further comprises encrypting the compressed set of identifier strings and error correction code.

17. The method of claim 15, wherein generating a code word using the set of identifier strings further comprises interleaving the compressed set of identifier strings and error correction code using an interleaver defined by a pseudo-random key.

18. The method of claim 17, further comprising encrypting the pseudo-random key.

19. The method of claim 13, further comprising:

assigning a serial number to the collection of items; and

encoding each RFID tag with a unique word generated using at least the serial number of the collection of items and an item sequence number included in the item identifier string of the item for which the RFID tag is produced.

20. The method of claim 13, wherein the unique word further comprises error correction code.

21. A method of identifying items in a collection that is identified by a collection serial number, where each item bears a memory encoded with a code word element, a collection serial number and an item sequence number, and where the items are not identifiable by reading an individual RFID tag affixed to the item, and where the combination of code word elements from a subset of the RFID tags contains information indicative of the set of item identifier strings, the method comprising:

reading the code word element, collection serial number and item sequence number from a plurality of memories;

discarding the code word element from memories that bear a collection serial number that does not match the serial number of the collection;

reordering the remaining code word elements in accordance with the item sequence numbers read from the memories;

forming a code word using the ordered code word elements;

extracting a set of item identifier strings from the code word; and

identifying the items in the collection using each of the item identifier strings.

22. The method of claim 21, further comprising extracting manifest information from the code word.

23. The method of claim 21, wherein forming a code word using the ordered code word elements, comprises recovering code word elements from memories that were not read using error correction information included in the code word elements that were read.

24. The method of claim 23, wherein forming a code word using the ordered code word elements, further comprises decrypting the complete set of code word elements.

25. The method of claim 23, wherein forming a code word using the ordered code word elements, further comprises decrypting a pseudo-random key and deinterleaving the complete set of code word elements using the pseudo-random key.

26. The method of claim 21, wherein identifying the items in the collection using each of the identifier strings further comprises:

extracting an item sequence number from each item identifier string; and

matching the extracted item sequence number against the item sequence number read from each memory.

27. The method of claim 26, further comprising constructing a record of the item identifier string corresponding to each item.

28. The method of claim 27, further comprising tracking an inventory by constructing a code word that combines the code word elements read from the memories of items in the inventory with stored code word elements associated with items known to have been removed from inventory.

29. The method of claim 21, wherein each memory is part of a separate RFID tag.

30. A system for encoding RFID tags, comprising:

an antenna configured to generate a signal formatted to encode an RFID tag;

a processor in communication with the antenna;

a memory in communication with the processor, where the memory contains item identifier strings for a collection of goods;

wherein the processor is configured to generate a code word using at least the item identifier strings;

wherein the processor is configured to extract a code word element from the code word and direct the antenna to generate a signal formatted to encode an RFID tag with the code word element, and

wherein the processor is configured to;

compress the item identifier strings;

generate error correction code using the compressed item identifier strings; and

generate the code word using at least the compressed item identifier strings and the error correction code.

31. The system of claim 30, wherein:

the memory also contains manifest information; and

the processor is configured to generate the code word using at least the item identifier strings and the manifest information.

32. The system of claim 30, wherein the processor is configured to encrypt the compressed item identifier strings and the error correction code.

33. The system of claim 30, wherein the processor is configured to interleave the compressed item identifier strings and the error correction code in accordance with a pseudo-random key and to encrypt the pseudo-random key.

34. The system of claim 30, wherein:

each item identifier string includes an item sequence number;

the memory contains a collection serial number;

the processor is configured to generate a unique word using at least the item sequence number and the collection serial number; and

the processor is configured to direct the antenna to generate a signal formatted to encode an RFID tag with the code word element and the unique word.

35. The system of claim 34, wherein the processor is configured to:

generate an error correction code using the item sequence number and the collection serial number; and

generate a unique word using at least the item sequence number, the collection serial number and the error correction code.

36. A system for decoding a collection of RFID tags identifiable using a collection serial number, where each RFID tag is encoded with a code word element, an item sequence number and a collection serial number, where the items are not identifiable by reading an individual RFID tag affixed to the item, and where the combination of code word elements from a subset of the RFID tags contains information indicative of the set of item identifier strings, comprising:

an RFID tag reader configured to read information from a plurality of RFID tags;

a processor configured to receive information from the RFID tag reader, store information from RFID tags that possess collection serial numbers that match the collection serial number of the collection and discard information from other RFID tags;

wherein the processor is also configured to reorder the code word elements in accordance with the item sequence numbers of the RFID tags from which the code word elements were read;

wherein the processor is also configured to create a code word using the code word elements; and

wherein the processor is also configured to extract item identifier sequences using the code word.

37. The system of claim 36, wherein the processor is further configured to extract manifest information from the code word.

38. The system of claim 36, wherein the processor is configured to recover code word elements from RFID tags that could not be read using error correction information included in the code word elements that were read.

39. The system of claim 38, wherein the processor is configured to decrypt the complete set of code word elements.

40. The system of claim 38, wherein the processor is configured to decrypt a pseudo-random key and deinterleave the complete set of code word elements using the pseudo-random key.

41. The system of claim 36, wherein the processor is configured to extracting an item sequence number from each item identifier string and match the extracted item sequence number against the item sequence number of each RFID tag.

42. The system of claim 36, wherein the processor is configured to construct a record of the item identifier string corresponding to each RFID tag.

43. The system of claim 42, wherein the processor is configured to:

store in the memory the code word elements of RFID tags known to have been removed from an inventory;

read RFID tags believed to be in inventory;

identify RFID tags believed to be in inventory that were not read; and

locate the item identifier string corresponding to the missing RFID tag within the record of the item identifier strings that corresponding to each RFID tag.