RFID tag with accelerometer

• US 7,956,725 B2
• Filed: 03/07/2007
• Issued: 06/07/2011
• Est. Priority Date: 09/24/2004
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Smith, Joshua R.
• Primary Examiner(s): Lee; Benjamin C
• Assistant Examiner(s): EUSTAQUIO, CAL J
• Application Number:
  US11/715,038
• Publication Number:
  US 20070182578A1
• Time in Patent Office: 1,553 Days
• Field of Search: 340/669, 340/671, 340/10.1
• US Class Current: 340/10.1
• CPC Class Codes: G06K 19/06 characterised by the kind of the digital marking, e.g. shape, nature, code
• 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 19/07345 by activating or deactivating at least a part of the circuit on the record carrier, e.g. ON/OFF switches

Abstract

One or more accelerometers may be coupled to a radio frequency identification (RFID) tag, so that the response of the RFID tag indicates the acceleration being sensed by the accelerometer(s). In some embodiments the accelerometers may be powered from the RF energy harvested by the RFID tag from a received RF signal. The sensed acceleration indicated in the response may be used to determine a motion and/or an orientation of an object coupled to the accelerometers.

Claims

1. An apparatus, comprising:

a first and second radio frequency identification (RFID) tag to transmit a response to a signal from an RFID reader;

a first accelerometer coupled to said first RFIFD tag and a second accelerometer coupled to said second RFID tag, said first and second accelerometers positioned with respect to one another to measure acceleration in different directions, only one of said accelerometers operative at any instance in time;

each of said RFID tags to provide an identifier and an acceleration value in response to a signal from an RFID reader so that the RFID reader can distinguish between the acceleration values from the first and second accelerometers based on the identifier of the first or second RFID tag; and

a single antenna for both of said tags.

2. The apparatus of claim 1, wherein operating power for the first accelerometer is to be provided by the first RFID tag.

3. The apparatus of claim 2, wherein the operating power for the first accelerometer is to be provided from energy harvested by the first RFID tag from a radio frequency signal received through an antenna of the first RFID tag.

4. The apparatus of claim 1, further comprising:

an object coupled to the first accelerometer;

the second accelerometer coupled to the object in an orientation perpendicular to the first accelerometer;

wherein first and second accelerometers are both to provide their sensed acceleration values to an RFID tag for transmission from an RFID tag.

5. The apparatus of claim 4, further comprising:

a third accelerometer coupled to the object in an orientation perpendicular to the first and second accelerometers;

wherein the third accelerometer is to provide its sensed acceleration value to an RFID tag for transmission from the RFID tag.

6. The apparatus of claim 1, further comprising at least one signal line coupled between the first accelerometer and the first REID tag to indicate a direction of the indicated amount of acceleration.