INTERROGATORS, WIRELESS COMMUNICATION SYSTEMS, METHODS OF OPERATING AN INTERROGATOR, METHODS OF MONITORING MOVEMENT OF A RADIO FREQUENCY IDENTIFICATION DEVICE, METHODS OF MONITORING MOVEMENT OF A REMOTE COMMUNICATION DEVICE AND MOVEMENT MONITORING METHODS

• US 6,356,230 B1
• Filed: 08/20/1999
• Issued: 03/12/2002
• Est. Priority Date: 08/20/1999
• Status: Expired due to Term

• Current Assignee: Round Rock Research LLC
• Original Assignee: Micron Technology, Inc.
• Inventors: Ovard, David, Greef, Roy
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US09/378,432
• Time in Patent Office: 935 Days
• Field of Search: 342/42, 342/44, 342/51, 342/56, 342/109, 342/125, 342/127, 342/133, 342/139, 342/146, 340/825.36
• US Class Current: 342/127
• CPC Class Codes: G01S 13/536 using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves
• CPC Class Codes: G01S 13/751 wherein the responder or reflector radiates a coded signal
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• 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

Interrogators, wireless communication systems, methods of operating an interrogator, methods of monitoring movement of a radio frequency identification device, methods of monitoring movement of a remote communication device and movement monitoring methods are provided. According to one aspect, an interrogator includes communication circuitry configured to output a forward wireless signal to a radio frequency identification device and to receive a return wireless signal from the radio frequency identification device; and a processor coupled with the communication circuitry and configured to process the return wireless signal to monitor movement of the radio frequency identification device. Another aspect provides a method of operating an interrogator including the steps of outputting a forward wireless signal; receiving a return wireless signal from a radio frequency identification device; processing the return wireless signal; and monitoring movement of the radio frequency identification device after the processing.

Claims

1. An interrogator comprising:

communication circuitry configured to output a forward wireless signal to a radio frequency identification device and to receive a return wireless signal from the radio frequency identification device; and

a processor coupled with the communication circuitry and configured to process the return wireless signal to monitor movement of the radio frequency identification device relative to the interrogator.

2. The interrogator according to claim 1 wherein the processor is configured to process the return wireless signal to determine a speed of the radio frequency identification device.

3. The interrogator according to claim 1 wherein the processor is configured to process the return wireless signal to determine a distance of travel of the radio frequency identification device.

4. The interrogator according to claim 1 wherein the processor is configured to process the return wirless signal to determine a change in position of the radio frequency identification device.

5. The interrogator according to claim 1 wherein the processor is configured to process the return wireless signal to determine phase of the return wireless signal at a plurality of moments in time.

6. The interrogator according to claim 1 wherein the processor is configured to process the return wireless signal to determine phase of the return wireless signal at a predefined moment in time.

7. The interrogator according to claim 1 wherein the processor is configured to process the return wireless signal to determine phase of the return wireless signal at an initial moment in time, to time a predefined period of time, and to process the return wireless signal to determine phase of the return wireless signal at a subsequent moment in time after timing the predefined period of time.

51. The interrogator according to claim 1 wherein the communication circuitry is configured to receive the return wireless signal at a single location and the processor is configured to monitor movement of the radio frequency identification device only using the return wireless signal received at the single location.

52. The interrogator according to claim 1 wherein the processor is configured to monitor movement of the radio frequency identification device without position information of the radio frequency identification device.

53. The interrogator according to claim 1 wherein the communication circuitry comprises coherent transmit circuitry and receive circuitry respectively configured to output the forward wireless signal and to receive the return wireless signal.

8. An interrogator comprising:

communication circuitry configured to output a forward wireless signal to a radio frequency identification device and to receive a return wireless signal from the radio frequency identification device; and

a processor coupled with the communication circuitry and configured to process the return wireless signal to determine a speed of the radio frequency identification device relative to the interrogator.

9. The interrogator according to claim 8 wherein the processor is configured to determine phase of the return wireless signal at a plurality of moments in time to determine the speed.

10. The interrogator according to claim 8 wherein the processor is configured to determine a distance of travel of the radio frequency identification device.

11. The interrogator according to claim 8 wherein the processor is configured to process the return wireless signal to determine phase of the return wireless signal at an initial moment in time, to time a predefined period of time, and to process the return wireless signal to determine phase of the return wireless signal at a subsequent moment in time after timing the predefined period of time.

12. A wireless communication system comprising:

an interrogator configured to output a forward wireless signal;

a radio frequency identification device configured to receive the forward wireless signal and output a return wireless signal responsive to the forward wireless signal; and

wherein the interrogator is configured to receive the return wireless signal and to monitor movement of the radio frequency identification device.

13. The system according to claim 12 wherein the interrogator is configured to determine a speed of the radio frequency identification device.

14. The system according to claim 12 wherein the interrogator is configured to determine a distance of travel of the radio frequency identification device.

15. The system according to claim 12 wherein the interrogator is configured to determine phase of the return wireless signal at a plurality of moments in time.

16. The system according to claim 12 wherein the interrogator is configured to process the return wireless signal to monitor the movement.

17. The system according to claim 12 wherein the interrogator is configured to determine phase of the return wireless signal at an initial moment in time, to time a predefined period of time, and to determine phase of the return wireless signal at a subsequent moment in time after timing the predefined period of time.

54. The system according to claim 12 wherein the interrogator is configured to receive the return wireless signal at a single location and to monitor movement of the radio frequency identification device only using the return wireless signal received at the single location.

55. The system according to claim 12 wherein the interrogator is configured to monitor movement of the radio frequency identification device without position information of the radio frequency identification device.

56. The system according to claim 12 wherein the interrogator comprises coherent transmit circuitry and receive circuitry respectively configured to output the forward wireless signal and to receive the return wireless signal.

18. A wireless communication system comprising:

an interrogator configured to output a forward wireless signal;

a remote communication device configured to receive the forward wireless signal and output a return wireless signal responsive to the forward wireless signal; and

wherein the interrogator includes communication circuitry configured to receive the return wireless signal and a processor configured to determine phase of the return wireless signal at a plurality of moments in time to monitor movement of the remote communication device.

19. The system according to claim 18 wherein the processor is configured to determine the phase of the return wireless signal to determine a speed of the remote communication device.

20. The system according to claim 18 wherein the interrogator is configured to determine the phase of the return wireless signal to determine a distance of travel of the radio frequency identification device.

21. The system according to claim 18 wherein the processor is configured to determine phase of the return wireless signal at a predefined moment in time.

22. The system according to claim 18 wherein the interrogator is configured to determine phase of the return wireless signal at an initial moment in time, to time a predefined period of time, and to determine phase of the return wireless signal at a subsequent moment in time after timing the predefined period of time.

57. The system according to claim 18 wherein the remote communication device comprises a radio frequency identification device.

65. The system according to claim 18 wherein the processor is configured to determine the phase of the return wireless signal at the plurality of moments in time during one period of the return wireless signal.

23. A wireless communication system comprising:

an interrogator configured to output a forward wireless signal;

a radio frequency identification device configured to receive the forward wireless signal and output a return wireless signal responsive to the forward wireless signal; and

wherein the interrogator includes communication circuitry configured to receive the return wireless signal and a processor configured to determine phase of the return wireless signal at an inial moment in time, to time a predefined period of time, and to determine phase at a subsequent moment in time after the predefined period of time to monitor movement of the radio frequency identification device.

24. The system according to claim 23 wherein the processor is configured to determine the phase of the return wireless signal to determine a speed of the radio frequency identification device.

25. The system according to claim 23 wherein the interrogator is configured to determine the phase of the return wireless signal to determine a distance of travel of the radio frequency identification device.

26. A method of operating an interrogator comprising steps of:

outputting a forward wireless signal;

receiving a return wireless signal from a radio frequency identification device;

processing the return wireless signal; and

monitoring movement of the radio frequency identification device after the processing.

27. The method according to claim 26 wherein the monitoring comprises determining speed of the radio frequency identification device.

28. The method according to claim 26 wherein the monitoring comprises determining a distance of travel of the radio frequency identification device.

29. The method according to claim 26 wherein the processing comprises determining phase of the return wireless signal at a plurality of moments in time.

30. The method according to claim 26 wherein the processing comprises determining phase of the return wireless signal at a predefined moment in time.

31. The method according to claim 26 wherein the monitoring includes:

determining phase of the return wireless signal at an initial moment in time;

timing a predefined period of time; and

determining phase of the return wireless signal at a subsequent moment in time.

58. The method according to claim 26 wherein the receiving comprises receiving at a single location and the monitoring comprises monitoring using only the return wireless signal received at the single location.

59. The method according to claim 26 wherein the monitoring comprises monitoring movement without position information of the radio frequency identification device.

60. The method according to claim 26 wherein the outputting and the receiving comprise outputting and receiving using respective ones of coherent transmit circuitry and receive circuitry.

32. A method of monitoring movement of a radio frequency identification device comprising steps of:

outputting a forward wireless signal using an interrogator;

receiving the forward wireless signal using a radio frequency identification device;

outputting a return wireless signal using the radio frequency identification device;

receiving the return wireless signal using the interrogator; and

monitoring movement of the radio frequency identification device responsive to the receiving the return wireless signal.

33. The method according to claim 32 wherein the monitoring comprises monitoring using the interrogator.

34. The method according to claim 32 wherein the monitoring comprises determining speed of the radio frequency identification device.

35. The method according to claim 32 wherein the monitoring comprises determining a distance of travel of the radio frequency identification device.

36. The method according to claim 32 wherein the processing comprises determining phase of the return wireless signal at a plurality of moments in time.

37. The method according to claim 32 wherein the processing comprises determining phase of the return wireless signal at a predefined moment in time.

38. The method according to claim 32 wherein the monitoring includes:

determining phase of the return wireless signal at an initial moment in time;

timing a predefined period of time after the determining; and

determining phase of the return wireless signal at a subsequent moment in time.

61. The method according to claim 32 wherein the receiving comprises receiving at a single location and the monitoring comprises monitoring using only the return wireless signal received at the single location.

62. The method according to claim 32 wherein the monitoring comprises monitoring movement without position information of the radio frequency identification device.

63. The method according to claim 32 wherein the outputting and the receiving comprise outputting and receiving using respective ones of coherent transmit circuitry and receive circuitry.

39. A method of monitoring movement of a remote communication device comprising steps of:

outputting a forward wireless signal;

receiving the forward wireless signal using a remote communication device;

outputting a return wireless signal using the remote communication device;

receiving a return wireless signal;

determining phase of the return wireless signal at a plurality of moments of time; and

monitoring movement of the remote communication device after the determining.

40. The method according to claim 39 wherein the monitoring comprises monitoring using the interrogator.

41. The method according to claim 39 wherein the monitoring comprises determining speed of the remote communication device.

42. The method according to claim 39 wherein the monitoring comprises determining a distance of travel of the remote communication device.

43. The method according to claim 39 wherein the determining comprises determining phase of the return wireless signal at one predefined moment in time.

44. The method according to claim 39 wherein the determining comprises:

determining phase of the return wireless signal at an initial point in time;

timing a predefined period of time after the determining; and

determining phase of the return wireless signal at a subsequent point in time after the timing.

64. The method according to claim 39 wherein the receiving comprises receiving using the remote communication device comprising a radio frequency identification device.

45. A movement monitoring method comprising steps of:

applying a wireless signal to a wireless communication device;

reflecting at least some of the wireless signal using the wireless communication device;

determining phase of the reflected wireless signal at an initial point in time;

timing a predefined period of time after the determining; and

determining phase of the reflected wireless signal at a subsequent point in time after the timing.

46. The method according to claim 45 wherein the applying, determinings, and timing individually comprise using an interrogator of a radio frequency identification device communication system.

47. The method according to claim 45 further comprising determining a speed of the wireless communication device after the determinings.

48. The method according to claim 45 further comprising determining a distance of travel of the wireless communication device after the determinings.

49. The method according to claim 45 wherein the reflecting comprises modulating the wireless signal using the wireless communication device comprising a radio frequency identification device.

50. A method of monitoring movement of a radio frequency identification device comprising steps of:

providing a wireless communication system including an interrogator and a radio frequency identification device;

generating a forward wireless signal having a frequency using the interrogator;

communicating the forward wireless signal to a radio frequency identification device;

reflecting at least some of the forward wireless signal using a radio frequency identification device;

receiving the reflected wireless signal using the interrogator;

determining phase of the reflected wireless signal at an initial point in time;

timing a predefined period of time after the determining;

determining phase of the reflected wireless signal at a subsequent point in time after the timing;

determining speed of the radio frequency identification device using the phase of the reflected wireless signal at the initial point in time, using the phase of the reflected wireless signal at the subsequent point in time, and using the predefined period of time; and

determining a distance of travel of the radio frequency identification device using the speed and predefined period of time.