RFID—sensor system for lateral discrimination

• US 7,612,675 B2
• Filed: 02/14/2007
• Issued: 11/03/2009
• Est. Priority Date: 02/14/2006
• Status: Active Grant

• Current Assignee: Technology Capital LLC
• Original Assignee: Technology Capital LLC
• Inventors: Miller, Ronald N., Richard, Christian
• Primary Examiner(s): Mehmood; Jennifer
• Application Number:
  US11/674,736
• Publication Number:
  US 20070194931A1
• Time in Patent Office: 993 Days
• Field of Search: 3405721-5729, 340 101- 106, 455/1
• US Class Current: 340/572.3
• CPC Class Codes: A63F 1/06 Card games appurtenances
• CPC Class Codes: G01S 13/751 wherein the responder or reflector radiates a coded signal
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01V 15/00 Tags attached to, or associated with, an object, in order to enable detection of the object record carriers for use with machines having a detectable tag or marker G06K19/00
• CPC Class Codes: G07F 17/322 Casino tables, e.g. tables having integrated screens, chip detection means
• CPC Class Codes: H04K 2203/20 for contactless carriers, e.g. RFID carriers
• CPC Class Codes: H04K 2203/32 including a particular configuration of antennas
• CPC Class Codes: H04K 2203/34 involving multiple cooperating jammers
• CPC Class Codes: H04K 3/41 characterized by the control of the jamming activation or deactivation time control of jamming activation and deactivation time only for the purpose of alternating between jamming mode and target monitoring mode H04K3/45
• CPC Class Codes: H04K 3/42 characterized by the control of the jamming frequency or wavelength
• CPC Class Codes: H04K 3/44 characterized by the control of the jamming waveform or modulation type
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
• CPC Class Codes: H04K 3/86 related to preventing deceptive jamming or unauthorized interrogation or access, e.g. WLAN access or RFID reading record carriers with integrated circuit chips including means for preventing undesired reading or writing from or to record carriers by hindering electromagnetic reading or writing G06K19/07318; arrangements for sensing record carriers including arrangements for protecting the interrogation against piracy attacks G06K7/10257
• CPC Class Codes: H04K 3/94 related to allowing or preventing testing or assessing

Abstract

The present invention is directed to a system for reading at least one object having a programmable RFID device embedded therein. The object is disposed in a predetermined reading region. The system includes a reader loop disposed in the predetermined reading region. The reader loop is configured to transmit a reader interrogation signal to the at least one object disposed in the predetermined reading region and receive an RFID signal from the at least one object in response to the reader interrogation signal. A jamming device is disposed proximate the reader loop. The jamming device is configured to generate a jamming signal that prevents an external reader device disposed outside the predetermined reading region from interrogating the at least one object disposed in the predetermined reading area.

Claims

1. A system for reading at least one object having a programmable RFID device embedded therein, the object being disposed in a predetermined reading region, the system comprising:

a reader loop disposed in the predetermined reading region, the reader loop being configured to transmit a reader interrogation signal to the at least one object disposed in the predetermined reading region and receive an RFID signal from the at least one object in response to the reader interrogation signal; and

a jamming device disposed proximate the reader loop, the jamming device being configured to generate a jamming signal that prevents an external reader device disposed outside the predetermined reading region from interrogating the at least one object disposed in the predetermined reading area.

2. The system of claim 1, wherein the jamming device is configured to generate the jamming signal in response to a jamming timing signal, the timing signal substantially coinciding with a transmission of a read signal from the external reader device disposed outside the predetermined reading area.

3. The system of claim 2, wherein the jamming timing signal is asynchronous relative to the read signal.

4. The system of claim 2, wherein the jamming timing signal is synchronous relative to the read signal.

5. The system of claim 1, wherein the jamming signal destructively interferes with an interrogation signal from the external reader device such that the interrogation signal does not substantially propagate inside the predetermined reading area.

6. The system of claim 1, wherein the jamming signal is configured to prevent the at least one object from detecting and/or responding to an interrogation signal from the external reader device.

7. The system of claim 6, wherein the jamming signal is an ASK modulated fixed frequency signal.

8. The system of claim 6, wherein the jamming signal is a continuous wave signal propagating at a frequency substantial equal to a frequency of the reader interrogation signal.

9. The system of claim 6, wherein the jamming signal is a continuous wave signal propagating at a frequency slightly offset from the frequency of the reader interrogation signal at an edge of an FCC allowed carrier band.

10. The system of claim 6, wherein the jamming signal is a phase modulated signal.

11. The system of claim 1, wherein the jamming signal is selected from a group of jamming signals including a frequency modulated signal, an amplitude modulated signal, a phase modulated signal, a noise modulated signal, a pseudo-random noise modulated signal, an FM chirp signal, or a code modulated signal.

12. The system of claim 1, wherein the jamming device includes a jamming coil disposed adjacent to the reader loop.

13. The system of claim 1, wherein the jamming device is a jamming coil disposed inside the reader loop.

14. The system of claim 13, wherein the reader loop and jamming coil are characterized by a geometry including circular, oval or rectangular geometries, and wherein the jamming coil is coplanar and co-axial to the reader loop, the jamming coil being disposed inside the reader loop.

15. The system of claim 1, wherein the jamming device includes a ferrite solenoid device.

16. The system of claim 1, wherein the jamming device includes a flux canceller loop.

17. The system of claim 1, wherein the at least one object includes at least one gaming chip, and wherein the predetermined reading region includes a gaming table, the at least one gaming chip being disposed on a surface of the gaming table, the reader loop and the jamming device being disposed under the surface of the gaming table.

18. The system of claim 17, wherein the gaming table is selected from a group of gaming tables including a baccarat gaming table, a Black Jack gaming table, a Pai Gow gaming table.

19. The system of claim 17, wherein the at least one gaming chip includes a plurality of gaming chips disposed in the predetermined reading region.

20. The system of claim 19, wherein the external reader device disposed outside the predetermined reading region is disposed in an adjacent reading region on the gaming table.

21. The system of claim 17, wherein the at least one gaming chip includes an American style gaming chip, a European style jeton gaming chip and/or a rectangular plaque.

22. The system of claim 1, wherein the predetermined reading region includes a retail display structure.

23. The system of claim 1, wherein the predetermined reading region includes a rack and the at least one object is a bottle, a test tube, and/or a biological sample holder.

24. The system of claim 1, wherein the predetermined reading region includes a chess board and the at least one object includes at least one chess piece.

25. The system of claim 1, wherein the at least one object includes jewelry or a tagged jewelry holder.

26. The system of claim 1, further comprising an RFID reader coupled to the reader loop, the RFID reader being configured to decode the RFID signal.

27. An RFID sensor system for reading at least one object having a programmable RFID device embedded therein, the at least one object being disposed in at least one of N -predetermined reading regions, N being an integer value greater than or equal to two, the system comprising:

N-RFID reader arrays, each N-RFID reader array being disposed in a corresponding one of the N-predetermined reading regions, an M^th RFID reader array of the N-RFID arrays including an M^th reader loop configured to read the at least one object disposed in an M^th region and an M^th jamming device disposed proximate the M^th reader loop, the M^th jamming device being configured to generate a jamming signal that prevents reader loops disposed in adjacent reading regions of the N-predetermined reading regions from reading the at least one object disposed in the M^th region, M being an integer value in a range of integers from 1 to N; and

a control system coupled to the N-RFID reader arrays, the control system being configured to energize each reader loop in accordance with a predetermined reading sequence and energize each jamming device in accordance with a predetermined jamming sequence.

28. The system of claim 27, wherein the control system is configured to energize at least one jamming device in at least one region adjacent to the M^th region when energizing the M^th reader loop.

29. The system of claim 28, wherein the at least one region adjacent to the M^th region includes an M−

1^th region and an M+1^th region.

30. The system of claim 27, wherein the predetermined reading sequence and the predetermined jamming sequence are synchronous.

31. The system of claim 27, wherein the predetermined reading sequence and the predetermined jamming sequence are asynchronous.

32. The system of claim 27, wherein each N-RFID reader array is an HF RFID coupler array.

33. The system of claim 27, wherein the N-predetermined reading regions include N -predefined positions on a gaming table, each of the N-RFID reader arrays being proximately disposed under the N-predefined positions.

34. The system of claim 33, wherein the gaming table is selected from a group of gaming tables including a baccarat gaming table, a Black Jack gaming table, a Pai Gow gaming table.

35. The system of claim 33, wherein the at least one object includes at least one gaming chip.

36. The system of claim 35, wherein the at least one gaming chip includes a plurality of gaming chips disposed in the at least one of the N-predetermined reading region.

37. The system of claim 27, wherein each jamming device in each of the N-RFID reader arrays is configured to generate a jamming signal in response to a jamming timing signal from the control system, the jamming timing signal substantially coinciding with a transmission of a read timing signal from the control system, the read timing signal configured to energize a reader loop disposed in an adjacent region of the N-predetermined reading regions.

38. The system of claim 37, wherein the jamming timing signal is asynchronous relative to the read timing signal.

39. The system of claim 37, wherein the jamming timing signal is synchronous relative to the read timing signal.

40. The system of claim 27, wherein the jamming signal destructively interferes with a reader interrogation signal generated by one of the M^th reader loop disposed in a region adjacent to the M^th region such that the interrogation signal does not substantially propagate inside the M^th region.

41. The system of claim 27, wherein the jamming signal is configured to prevent the at least one object from detecting and/or responding to a reader interrogation signal generated by one of the M^th reader loop disposed in a region adjacent to the M^th region.

42. The system of claim 41, wherein the jamming signal is an ASK modulated fixed frequency signal.

43. The system of claim 41, wherein the jamming signal is a continuous wave signal propagating at a frequency substantially equal to a frequency of the reader interrogation signal.

44. The system of claim 41, wherein the jamming signal is a continuous wave signal propagating at a frequency slightly offset from the frequency of the reader interrogation signal at an edge of an FCC allowed carrier band.

45. The system of claim 41, wherein the jamming signal is a phase modulated signal.

46. The system of claim 41, wherein the jamming signal is selected from a group of jamming signals including a frequency modulated signal, an amplitude modulated signal, a phase modulated signal, a noise modulated signal, a pseudo-random noise modulated signal, an FM chirp signal, or a code modulated signal.

47. The system of claim 27, wherein the M^th jamming device disposed in at least one of the N-RFID reader arrays includes a jamming coil disposed inside a reader loop.

48. The system of claim 47, wherein the reader loop and jamming coil are characterized by a geometry including circular, oval or rectangular geometries, and wherein the jamming coil is coplanar and co-axial to the reader loop, the jamming coil being disposed inside the reader loop.

49. The system of claim 27, wherein the jamming device includes a ferrite solenoid device.

50. The system of claim 27, wherein the jamming device includes a flux canceller loop.

51. The system of claim 27, further comprising at least one fixed RFID device coupled to the control system and configured to monitor the jamming signal and determine a jamming device effectiveness, the at least one fixed RFID device adaptively setting relative levels of the jamming signal and reader loop read signals in accordance with the jamming device effectiveness.

52. The system of claim 51, wherein the at least one fixed RFID device includes a plurality of fixed RFID devices configured to adaptively set by sensing the jamming device effectiveness on fixed chips permanently installed in various locations within a gaming table surface and controlling the level of the jamming signal and reader loop read signals either on initial set-up or periodically during use.

53. The system of claim 27, wherein the M^th jamming device disposed in at least one of the N-RFID reader arrays includes a jamming coil disposed adjacent to the M^th reader loop.