Tag and tagging system

• US 20050029359A1
• Filed: 09/16/2002
• Published: 02/10/2005
• Est. Priority Date: 09/14/2001
• Status: Active Grant

• Current Assignee: ROKE Manor Research Limited (Chemring Group PLC)
• Original Assignee: ROKE Manor Research Limited (Chemring Group PLC)
• Inventors: Richardson, Christopher Keith
• Granted Patent: US 7,568,630 B2
• Time in Patent Office: Days
• US Class Current: 235/492
• CPC Class Codes: G06K 19/067 Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
• CPC Class Codes: G08B 13/2417 having a radio frequency identification chip

Abstract

A tag comprising a plastic container having at least one particle therein. The or each particle may be formed from metal or metal coated and/or fabricated from a plurality of different metals. A receiver unit adapted to detect RF pulses arising as a result of the Triboelectric effect of the particles enables detection of a tag.

Claims

1. A tag comprising a container in which there is at least one particle, arranged to be displaced with respect to the container so that a radio frequency (RF) signature is emitted, said RF signature being capable of identifying the tag.

2. A tag as claimed in claim 1 having a plurality of particles.

3. A tag as claimed in claim 1, wherein the or each particle is/are metal or metal coated.

4. A tag as claimed in claim 3 wherein the metal or metal coated particle(s) are fabricated from a plurality of different metals.

5. A tag according to claim 1, having two or more metallic strips disposed on the surface of the container arranged to detect displacement of the or each particle.

6. A tag according to claim 5 wherein the relative location and/or dimension and/or number of strips on a tag is different, thereby providing a different RF signature upon displacement of the or each particle.

7. A tagging system comprising a tag as claimed in claim 1, and a receiver unit adapted to detect RF signals.

8. A tagging system as claimed in claim 7 wherein the receiver is a wideband receiver having a bandwidth of at least 0.5 GHz.

9. A tagging system as claimed in claim 7 wherein the receiver is a wideband receiver having a bandwidth of at least 1 GHz.

10. A tagging system as claimed in claim 7, having means to locate the tag.

11. A tagging system as claimed in claim 10 wherein the means to locate the tag includes first and second receivers which are operative to locate a tag based upon the time of arrival of a signal at each receiver.

12. A method of tagging an object using a tag according to claim 1 and detecting RF signals.

13. A method as claimed in claim 12 wherein different tags are distinguished by virtue of the number and type of particles in each tag.