Rfid reader management system and method

• US 8,253,539 B2
• Filed: 11/30/2004
• Issued: 08/28/2012
• Est. Priority Date: 11/30/2004
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Scaramozzino, Umberto R.
• Primary Examiner(s): BROWN, VERNAL U
• Application Number:
  US11/000,795
• Publication Number:
  US 20060114104A1
• Time in Patent Office: 2,828 Days
• Field of Search: 340/10.2, 340/10.1, 340/825.69, 340/825.72, 340/572.1, 340/825.49, 340/572.2, 340/10.4, 340/5.61, 340/10.5, 340/10.3, 340/505
• US Class Current: 340/10.2
• CPC Class Codes: G01S 5/0246 involving frequency difference of arrival or Doppler measurements G01S5/02685 takes precedence
• 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
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas

Abstract

A system and method is provided for managing RFID readers. The system and method manages RFID readers by controlling the RFID readers to reduce interference between RFID transmissions. The system and method locates RFID readers, including mobile and fixed RFID readers, and controls the transmitting of the RFID readers such that proximate readers do not transmit simultaneously. This reduces the interference between RFID readers, and thus can improve the reliability and accuracy of the RFID system.

Claims

1. An RFID reader management system, the RFID reader management system comprising:

an RFID reader locator, the RFID reader locator locating a mobile RFID reader and at least one other RFID reader; and

an RFID reader controller, the RFID reader controller determining if any RFID reader in the at least one other RFID reader is proximate to the mobile RFID reader, the RFID reader selectively controlling the mobile RFID reader and the at least one other RFID reader such that the mobile RFID reader and the any RFID reader in the least one other RFID reader that is determined to be proximate to the mobile RFID reader do not transmit simultaneously to reduce interference between the mobile RFID reader and the at least one other RFID reader.

2. The system of claim 1 wherein the RFID reader locator locates the mobile RFID reader using received signal strength.

3. The system of claim 1 wherein the RFID reader locator locates the mobile RFID reader using time difference of arrival.

4. The system of claim 1 wherein the RFID reader locator locates the mobile RFID reader using angle of arrival.

5. The system of claim 1 wherein the RFID reader locator locates the mobile RFID reader using phase difference of arrival of backscatter modulated signals from an RFID tag.

6. The system of claim 1 wherein the mobile RFID reader includes a mobile RFID reader RFID tag and wherein the mobile RFID reader tag is utilized to determine a location of the mobile RFID reader.

7. The system of claim 1 wherein the mobile RFID reader communicates using an 802.11x protocol transmission and wherein the RFID reader locator uses an 802.11x protocol transmission to locate the mobile RFID reader.

8. The system of claim 1 wherein the mobile RFID reader communicates using a Bluetooth protocol transmission and wherein the RFID reader locator system uses the Bluetooth protocol transmission to locate the mobile RFID reader.

9. The system of claim 1 wherein the RFID reader locator locates the at least one other RFID reader using an RFID reader mapping database.

10. The system of claim 1 wherein the at least one other RFID reader comprises an array of fixed RFID readers.

11. The system of claim 1 wherein the RFID reader controller selectively controls the mobile RFID and the at least one other RFID reader by assigning each of the mobile RFID and the at least one other RFID reader a different time slice.

12. The system of claim 11 wherein the RFID reader locater locates the mobile RFID reader RFID reader when a user activates the mobile RFID reader, and wherein the RFID reader controller assigns the mobile RFID reader a time slice when activated by the user and located.

13. A method of managing RFID readers, the method comprising the steps of:

locating a mobile RFID reader and at least one other RFID reader;

determining if any RFID reader in the at least one other RFID reader is proximate to the mobile RFID reader; and

controlling the mobile RFID reader and the at least one other RFID reader such that the mobile RFID reader and the any RFID reader in the least one other RFID reader that is determined to be proximate to the mobile RFID reader do not transmit simultaneously to reduce interference between the mobile RFID reader and the at least one other RFID reader.

14. The method of claim 13 wherein the step of locating comprises locating the mobile RFID reader using received signal strength.

15. The method of claim 14 wherein the step of locating comprises locating the mobile RFID reader using time difference of arrival.

16. The method of claim 13 wherein the step of locating comprises locating the mobile RFID reader using angle of arrival.

17. The method of claim 13 wherein the step of locating comprises locating the mobile RFID reader using phase difference of arrival of backscatter modulated signals from an RFID tag.

18. The method of claim 13 wherein the mobile RFID reader includes a mobile RFID reader RFID tag and wherein the step of locating comprises locating the mobile RFID reader using the RFID tag.

19. The method of claim 13 wherein the mobile RFID reader communicates using an 802.11x protocol transmission and wherein the step of locating comprises using the 802.11x protocol transmissions to locate the mobile RFID reader.

20. The method of claim 13 wherein the mobile RFID reader communicates using a Bluetooth protocol transmission and wherein the step of locating comprises using the Bluetooth protocol transmission to locate the mobile RFID reader.

21. The method of claim 13 wherein the step of locating comprises locating the at least one other RFID reader using an RFID reader mapping database.

22. The method of claim 13 wherein the at least one other RFID reader comprises an array of fixed RFID readers.

23. The method of claim 13 wherein the step of controlling the mobile RFID reader and the at least one other RFID reader to reduce interference between the mobile RFID reader and the at least one other RFID reader comprises assigning each of the mobile RFID and the at least one other RFID reader a different time slice.

24. The method of claim 23 wherein the step of locating the mobile RFID reader comprises locating the mobile RFID when a user activates the mobile RFID reader, and wherein the step of controlling the mobile RFID reader and the at least one other RFID reader to reduce interference between the mobile RFID reader and the at least one other RFID reader comprises assigning the mobile RFID a time slice when activated by the user and located.

25. An RFID reader management system, the RFID reader management system comprising:

an RFID reader locator, the RFID reader locator locating a mobile RFID reader in real time;

an RFID reader controller, the RFID reader controller determining what other RFID readers in an array of RFID readers are proximate to the mobile RFID reader, the RFID reader controller assigning the mobile RFID reader a different time slice than the other RFID readers in the array of RFID readers that are determined proximate the mobile RFID reader.

26. The system of claim 25 wherein the RFID reader locater locates the mobile RFID reader RFID reader when a user activates the mobile RFID reader, and wherein the RFID reader controller assigns the mobile RFID reader a time slice when activated by the user and located.

27. A method of managing RFID readers, the method comprising the steps of:

locating a mobile RFID reader in real time;

determining what other RFID readers in an array of RFID readers are proximate to the mobile RFID reader; and

assigning the mobile RFID reader a different time slice than the other RFID readers in the array of RFID readers that are determined proximate the mobile RFID reader.

28. The method of claim 27 wherein the step of locating the mobile RFID reader comprises locating the mobile RFID when a user activates the mobile RFID reader, and wherein the step of assigning the mobile RFID reader a different time slice than the other RFID readers in the array of RFID readers comprises assigning the mobile RFID a time slice when activated by the user and located.