Interfacing to RFID reader utility that causes RFID tags to reply using changed reply timing

• US 8,063,740 B1
• Filed: 10/01/2008
• Issued: 11/22/2011
• Est. Priority Date: 02/20/2008
• Status: Active Grant

• Current Assignee: Impinj, Inc.
• Original Assignee: Impinj, Inc.
• Inventors: Diorio, Christopher J., Kavounas, Gregory T., Enyedy, Arthur Gustav
• Primary Examiner(s): Mehmood; Jennifer
• Assistant Examiner(s): Rushing; Mark
• Application Number:
  US12/243,144
• Time in Patent Office: 1,147 Days
• Field of Search: None
• US Class Current: 340/10.1
• CPC Class Codes: G06K 7/10009 sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• CPC Class Codes: H02K 15/024 with slots

Abstract

Interfacing is provided, to a utility of an RFID reader. The utility causes the RFID reader to instruct tags to reply using changed reply timing. The interfacing enables an agent to control the utility, for installing it, configuring it, enabling it, disabling it, or operating it. In a number of embodiments, the tag timing change is achieved by causing a custom timing command to be transmitted to a tag. In some embodiments, the changed reply timing alters the delay before a tag backscatters a reply.

Claims

1. A method for an interface converter operable to control a utility of a Radio Frequency Identification (RFID) reader that can communicate with an RFID tag, the tag having received a first command, and backscattered a first reply responsive to the first command, the tag using a first delay before backscattering the first reply after receiving the first command, the utility operable to cause the RFID tag to reply using a changed reply timing by causing the reader to transmit to the tag a custom timing command, the tag then backscattering a second reply that encodes the same functional content as the first reply, the tag using a second delay before backscattering the second reply after receiving a most recent command prior to backscattering the second reply, the second delay different from the first delay responsive to receiving the custom timing command, the method comprising:

receiving a high down transmission to control the utility in a first manner; and

responsive to the high down transmission, transmitting a low down transmission to control the utility in the first manner, the low down transmission being encoded differently than the high down transmission at least in part.

2. The method of claim 1, in which

the functional content is one of a code stored in a memory, and a random number.

3. The method of claim 1, in which

the first command is a command to identify,

the first reply is an identifying reply, and

in which the custom timing command is caused to be transmitted responsive to the identifying reply.

4. The method of claim 1, in which

the most recent command is one of a command to identify and the custom timing command.

5. The method of claim 1, in which

a Tune command is caused to be transmitted to the tag, which encodes a time-indicating parameter, and

the second delay is determined from the time-indicating parameter.

6. The method of claim 5, in which

the Tune command is one of the first command and the custom timing command.

7. The method of claim 1, in which

the utility is implemented as part of one of the RFID reader and a device other than the RFID reader.

8. The method of claim 1, in which

the first manner includes at least one from a set of:

installing, enabling, disabling, configuring, and operating the utility.

9. The method of claim 1, in which

the high down transmission includes a time parameter, and

the second delay is controlled from the time parameter.

10. The method of claim 1, in which

a low up transmission is received responsive to transmitting the low down transmission, and

responsive to receiving to the low up transmission, a high up transmission is transmitted.

11. An interface converter operable to control a utility of a Radio Frequency Identification (RFID) reader that can communicate with an RFID tag, the tag having received a first command, and backscattered a first reply responsive to the first command, the tag using a first delay before backscattering the first reply after receiving the first command, the utility operable to cause the RFID tag to reply using a changed reply timing by causing the reader to transmit to the tag a custom timing command, the tag then backscattering a second reply that encodes the same functional content as the first reply, the tag using a second delay before backscattering the second reply after receiving a most recent command prior to backscattering the second reply, the second delay different from the first delay responsive to receiving the custom timing command, the interface converter configured to:

receive a high down transmission to control the utility in a first manner; and

responsive to the high down transmission, transmit a low down transmission to control the utility in the first manner, the low down transmission being encoded differently than the high down transmission at least in part.

12. The interface converter of claim 11, in which the functional content is one of a code stored in a memory, and a random number.

13. The interface converter of claim 11, in which

the first command is a command to identify,

the first reply is an identifying reply, and

in which the custom timing command is caused to be transmitted responsive to the identifying reply.

14. The interface converter of claim 11, in which

the most recent command is one of a command to identify and the custom timing command.

15. The interface converter of claim 11, in which

a Tune command is caused to be transmitted to the tag, which encodes a time-indicating parameter, and

the second delay is determined from the time-indicating parameter.

16. The interface converter of claim 15, in which

the Tune command is one of the first command and the custom timing command.

17. The interface converter of claim 11, in which

the utility is implemented as part of one of the RFID reader and a device other than the RFID reader.

18. The interface converter of claim 11, in which

the first manner includes at least one from a set of:

installing, enabling, disabling, configuring, and operating the utility.

19. The interface converter of claim 11, in which

the high down transmission includes a time parameter, and

the second delay is controlled from the time parameter.

20. The interface converter of claim 11, in which

a low up transmission is received responsive to transmitting the low down transmission, and

responsive to receiving to the low up transmission, a high up transmission is transmitted.