Temporary non-responsive state for RFID tags

• US 20080238680A1
• Filed: 03/30/2007
• Published: 10/02/2008
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Smith, Joshua R., Posamentier, Joshua D.
• Granted Patent: US 8,149,120 B2
• Time in Patent Office: Days
• US Class Current: 340/572.3
• 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
• CPC Class Codes: G06K 7/10029 the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot

Abstract

A radio frequency identification (RFID) tag may have a non-responsive mode, triggered by a command from an RFID reader, that temporarily prevents the RFID tag from responding to a query from any RFID reader for a period of time. In some embodiments this non-responsive mode may automatically end after a certain period of time without further action by the RFID reader. In other embodiments this non-responsive mode may end when directed to by another command addressed specifically to the RFID tag.

Claims

1. An apparatus, comprising

a radio frequency identification (RFID) tag containing circuitry to:

receive a first wireless command directed to the RFID tag from an RFID reader;

enter, resultant to said receiving the first wireless command, a non-responsive mode during which the RFID tag does not transmit responses to any RFID reader; and

exit the non-responsive mode based on a timing circuit within the RFID tag.

2. The apparatus of claim 1, wherein an intended duration of the non-responsive mode is determined by contents of the first wireless command.

3. The apparatus of claim 1, wherein:

the timing circuit comprises a capacitor;

the capacitor is to be charged to a first voltage level resultant to receiving the first wireless command; and

the non-responsive mode is to end resultant to the capacitor discharging to a second voltage level.

4. The apparatus of claim 3, wherein:

the RFID tag is a passive RFID tag; and

said discharging is to continue at approximately a same rate when the passive RFID tag is not receiving an energizing signal from any RFID reader.

5. The apparatus of claim 3, wherein the capacitor is to be recharged resultant to the RFID tag detecting a query while in the non-responsive mode.

6. The apparatus of claim 3, wherein the first voltage level is to be indicated in the first wireless command.

7. The apparatus of claim 3, wherein a rate of discharge of the capacitor is to be indicated in the first wireless command.

8. The apparatus of claim 1, wherein the timing circuit comprises a counter;

and the non-responsive mode is to end when the counter reaches a certain value.

9. The apparatus of claim 8, wherein the timing circuit may be reset to a particular value by receipt of a second wireless command during the non-responsive mode.

10. An apparatus, comprising

a radio frequency identification (RFID) tag, containing circuitry to:

receive a particular wireless command directed to the RFID tag from a particular RFID reader;

enter, resultant to said receiving the particular command, a non-responsive mode during which the RFID tag does not transmit responses to any RFID reader; and

exit the non-responsive mode resultant to the particular RFID tag receiving a command addressed to the RFID tag directing the RFID tag to exit the non-responsive mode.

11. A method, comprising:

receiving a wireless command from a radio frequency identification (RFID) reader to enter a non-responsive mode of operation,

entering the non-responsive mode resultant to receiving the command; and

returning to a responsive mode resultant to an internal event not based on any wireless command received while in the non-responsive mode.

12. The method of claim 11, wherein the internal event comprises expiration of a time period.

13. The method of claim 12, wherein the expiration of the time period is determined by a capacitor discharging to a particular voltage level.

14. The method of claim 12, wherein the expiration of the time period is determined by reaching a certain value in a counter.

15. A method, comprising:

receiving, by a radio frequency identification (RFID) tag, a first wireless command from an RFID reader to enter a non-responsive mode of operation,

entering the non-responsive mode as a result of receiving the first wireless command; and

receiving a second wireless command addressed to the RFID tag, the second wireless command directing the RFID tat to enter a responsive mode of operation; and

exiting the non-responsive mode resultant to receiving the second wireless command.

16. An article comprising

a tangible machine-readable medium that contains instructions, which when executed by one or more processors result in performing operations comprising:

transmitting an enabling signal to multiple radio frequency identification (RFID) tags;

receiving a response from a particular RFID tag; and

transmitting a first command addressed to the particular RFID tag and directing the particular RFID tag to enter a non-responsive mode.

17. The article of claim 16, wherein the operation of transmitting the first command comprises transmitting an indicator of an intended duration of the non-responsive mode.

18. The article of claim 16, wherein the operations further comprise transmitting a second command addressed to the particular RFID tag and directing the particular RFID tag to exit the non-responsive mode.