System and method for detecting transponders used with printer media

• US 7,190,270 B2
• Filed: 11/05/2004
• Issued: 03/13/2007
• Est. Priority Date: 11/05/2004
• Status: Active Grant

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: ZIH Corp. (Zebra Technologies Corporation)
• Inventors: Torchalski, Karl, Brown, Anthony R., Shuff, William, Ream, Matt, Borisov, Eugene
• Primary Examiner(s): PHAM, TOAN NGOC
• Application Number:
  US10/981,967
• Publication Number:
  US 20060109496A1
• Time in Patent Office: 858 Days
• Field of Search: 340/572.1, 340/572.4, 340/572.7, 340/572.8, 340/686.1, 340/686.6, 340/539.21, 235/432, 235/449, 235/451
• US Class Current: 340/572.1
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06K 17/0025 the arrangement consisting of a wireless interrogation device in combination with a device for optically marking the record carrier
• 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

A calibration apparatus for determining a location of a transponder supported by a printer media. The calibration apparatus uses a transceiver to attempt to read, write or otherwise communicate with the transponder. Controller logic of the calibration apparatus uses successful and unsuccessful attempts to communicate to determine the location of the transponder. For example, the controller may be configured to move the media in increments, each of the increments associated with a successful or unsuccessful attempt to communicate with the transponder. The successful attempts, and their relative media positions, are correlated with the position of the transponder. Also, the controller may be configured to use different power levels for the transceiver and its one or more couplers to determine which power levels are required to successfully communicate with the transponder. These power levels are correlated with characteristics of the performance of the transponder to determine its distance from the antenna/coupler.

Claims

1. An apparatus for determining a communication location of a transponder supported by a printer media, said calibration apparatus comprising:

a transceiver configured to communicate with the transponder;

a controller connected in communication with the transceiver and including communication logic configured to operate the transceiver and determine when the transceiver has successfully and unsuccessfully communicated with the transponder; and

said controller further including location logic configured to determine the location of the transponder relative to the transceiver based on at least one unsuccessful and one successful communication with the transponder.

2. An apparatus of claim 1, wherein the controller is further configured to change a position of the media in between communications with the transponder.

3. An apparatus of claim 2, wherein the communication logic is further configured to record a plurality of consecutive successful communications by the transceiver, each of the communications being associated with a changed position of the media, and wherein the location logic is further configured to determine the location of the transponder using the consecutive successful communications.

4. An apparatus of claim 3, wherein the location logic is configured to define a midpoint of the consecutive successful communications as the location of the transponder.

5. An apparatus of claim 4, wherein the communication logic is configured to record a second plurality of successful communications, and wherein the location logic is configured to define the midpoint of the first plurality of successful communications as the location of the transponder.

6. An apparatus of claim 5, wherein the changed position is at least one dot row of print.

7. An apparatus of claim 6, wherein the controller includes transponder identification logic configured to identify the transponder and operate the transceiver accordingly.

8. An apparatus of claim 7, wherein the controller includes logic for diagnosing problems using communication data from the transceiver.

9. An apparatus of claim 1, wherein the communication logic is configured to supply power at a plurality of levels to the transceiver, wherein a first one of the power levels is associated with the unsuccessful communication and a second one of the power levels is associated with the successful communication.

10. An apparatus of claim 9, wherein the communication logic is configured to identify a type of the transponder.

11. An apparatus of claim 10, wherein the location logic is configured to reference the power levels and the communications to characteristics of the type of the transponder to determine the location of the transponder.

12. An apparatus of claim 11, wherein the transceiver includes at least a first and second antenna couplers having different positions relative to the printer media and are each configured to communicate with the transponder.

13. An apparatus of claim 12, wherein the first and second antenna couplers are positioned so as to have compensating communication ranges.

14. An apparatus of claim 13, wherein the first and second antenna couplers are positioned on opposite sides of the transponder.

15. An apparatus of claim 13, wherein the communication logic is configured to independently power each of the antenna couplers.

16. An apparatus of claim 15, wherein the communication logic is configured to alternatively power each of the antenna couplers.

17. A method of detecting a transponder communication location on media, said method comprising:

attempting to communicate with the transponder using a transceiver;

detecting at least one successful attempt to communicate with the transponder;

detecting at least one unsuccessful attempt to communicate with the transponder; and

locating the transponder relative to the transceiver based on the at least one unsuccessful and one successful communication with the transponder.

18. A method of claim 17, further comprising changing a position of the media relative to the transceiver between detecting communication attempts.

19. A method of claim 18, further comprising detecting a plurality of consecutive successful attempts to communicate with the transponder, each of the successful attempts associated with a different media position, and wherein locating the transponder includes determining the location of the transponder using the consecutive successful communications.

20. A method of claim 19, wherein locating the transponder includes defining a midpoint of the different media positions associated with the consecutive successful communications.

21. A method of claim 20, wherein each of the different media positions is at least one dot row of print.

22. A method of claim 21, further comprising detecting a type of the transponder and wherein attempting to communicate with the transceiver is in accordance with the type of the transponder.

23. A method of claim 22, further comprising providing data on the successful and unsuccessful communications for diagnosis of problems.

24. A method of claim 17, wherein attempting to communicate with the transponder includes supplying power at a plurality of levels to the transceiver, wherein a first one of the power levels is associated with the unsuccessful communication and a second one of the power levels is associated with the successful communication.

25. A method of claim 24, further comprising detecting a type of the transponder to facilitate attempts to communicate therewith.

26. A method of claim 25, wherein locating the transponder includes referencing the power levels and the communications to characteristics of the type of the transponder.

27. A method of claim 26, wherein attempting to communicate with the transponder includes attempting to communicate through different antenna couplers of the transceiver.

28. A method of claim 27, wherein communicating through different antenna couplers includes positioning the couplers to have compensating communication ranges.

29. A method of claim 28, wherein positioning the antenna couplers includes positioning the antenna couplers on opposite sides of the transponder.

30. A method of claim 29, wherein supplying power at the plurality of levels to the transceiver includes alternatively powering each of the antenna couplers.

31. A method of claim 29, further comprising changing a position of the media relative to the transceiver between detecting communication attempts and wherein supplying power at the plurality of levels to the transceiver includes alternatively and simultaneously powering each of the antenna couplers.

32. For use in apparatus in which a passive RF transponder is located in the field of an RF transceiver configured to communicate with the transponder, a method for determining when a predetermined state of communication between the transponder and transceiver exists, the method comprising:

causing the transceiver to send a signal to the transducer and sensing a characteristic of the signal that is returned by the transponder;

one or more times adjusting a parameter of the communication link established to cause the signal returned by the transponder to change; and

determining from the parameter adjustments and return signal variations when a predetermined state of communication exists between the transponder and the transceiver.

33. A method of claim 32 wherein the predetermined state of communication is maximized or acceptable signal strength of the return signal.

34. A method of claim 33 wherein adjusting a parameter of the communication link comprises physically moving the transponder.

35. A method of claim 34 wherein the transponder is moved in steps.

36. A method of claim 32 wherein adjusting a parameter of the communication link comprises changing the power level of the signal sent by the transceiver.

37. A method of claim 36 wherein the power level of the transceiver signal is adjusted in steps.

38. A method of claim 32 wherein the power level of the signal sent by the transceiver and physical location of the transducer are both adjusted either individually or together.

39. A method of claim 32 wherein the parameters of the communication link when the predetermined state is determined are stored for future reference.

40. A method of claim 32 wherein the parameter adjustments are deliberately made to cause at least one condition of non-communication.

41. A method of claim 32 wherein the parameter adjustments are such that a succession of successful communication links are established between the transponder and transceiver.

42. A method of claim 32 wherein a plurality of transceivers are employed.

43. For use in a thermal printer in which a label carrying a passive RFID transponder is located in the field of an RF transceiver configured to communicate with the transponder for purposes of encoding or reading the transducer, a method for determining when an optimal or acceptable state of communication exists between the transponder and transceiver, the method comprising:

causing the transceiver to send a signal to the transducer and sensing the amplitude or power of the signal that is returned by the transponder;

one or more times adjusting the power of the transceiver or the physical location of the transponder to cause the signal returned by the transponder to change; and

determining from the return signal variations that occur when transceiver power or transponder location adjustments are made when a state of optimal or acceptable communication exists between the transponder and the transceiver.

44. A method of claim 43 wherein the power level of the signal sent by the transceiver and physical location of the transducer are both adjusted either individually or together.

45. A method of claim 43 wherein the parameters of the communication link when the predetermined state is determined are stored for future reference.

46. A method of claim 43 wherein the parameter adjustments are deliberately made to cause at least one condition of non-communication between the transponder and transceiver.

47. A method of claim 43 wherein the parameter adjustments are such that a succession of successful communication links are deliberately established between the transponder and transceiver.

48. A method of claim 43 wherein a plurality of transceivers are employed.