Microwave barcode reader using dipole antenna

• US 20020063156A1
• Filed: 11/29/2000
• Published: 05/30/2002
• Est. Priority Date: 11/29/2000
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Marchand, J. F. Philippe
• Granted Patent: US 6,547,140 B2
• Time in Patent Office: Days
• US Class Current: 235/462.01
• 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: G06K 19/0672 with resonating marks

Abstract

A microwave barcode system is provided wherein the barcode comprises a plurality of conductive wires, mounted on a surface, or embedded beneath the surface of the object. A transmitter, comprising a dipole antenna, radiates microwave signals in the direction of the surface, and a microwave reader, comprising a dipole antenna positioned to receive the microwave signals passing through the surface, senses an attenuation of the microwave signal caused by a resonant interaction between the microwave signals and the conductive wires. The conductive wires of the present invention can be mounted in a stand-up fashion, wherein each wire is mounted adjacent to and parallel to, but not touching, its at least one neighbor, or in a lay-down fashion, wherein each wire is mounted coincident with an imaginary line which is also coincident with the remaining wires, and wherein the wires are mounted end-to-end with a gap surrounding each wire end. Both stand-up and lay-down versions of the barcode may be employed simultaneously without interference between the two versions.

Claims

1. A microwave barcode system comprising:

a barcode comprising a plurality of conductive wires mounted on at least one of a surface of an object and below a surface of the object;

a transmitter radiating microwave signals in the direction of the object; and

,

a microwave reader, including a dipole antenna, positioned to receive the microwave signals passing through the surface of the object wherein the reader senses an attenuation of the microwave signal caused by a resonant interaction between the microwave signals and the conductive wires.

2. The microwave barcode system of claim 1, wherein the plurality of conductive wires is comprised of a plurality of lengths, and each unique length corresponds to a unique datum value.

3. The microwave barcode system of claim 2, wherein the conductive wires are mounted in a stand-up fashion, and each wire is mounted adjacent to and parallel to, but not touching, its at least one neighbor.

4. The microwave barcode system of claim 2, wherein the conductive wires are mounted in a lay-down fashion, each wire is mounted coincident with an imaginary line which is also coincident with the remaining wires, and the wires are mounted end-to-end with a gap surrounding each wire end.

5. The microwave barcode system of claim 2, wherein the barcode comprises:

a stand-up barcode, wherein each wire is mounted adjacent to and parallel to, but not touching, its at least one neighbor; and

,

and a lay-down barcode, wherein each wire is mounted coincident with an imaginary line which is also coincident with the remaining wires, and the wires are mounted end-to-end with a gap surrounding each wire end.

6. The microwave barcode system of claim 1, wherein the plurality of conductive wires is comprised of equal length wires, each wire is mounted at an angle selected from a plurality of angles, and each unique angle corresponds to a unique datum value.

7. The microwave barcode system of claim 1, wherein the transmitter is comprised of a dipole antenna.

8. The microwave barcode system of claim 1, wherein the dipole antenna includes:

two conductive receiving elements; and

,

a detector diode connected to bridge the receiving elements.

9. The microwave barcode system of claim 1, wherein the barcode is at least one of a stand-up barcode and a lay-down barcode.

10. The microwave barcode system of claim 9, wherein the stand-up barcode and the lay-down barcode are mounted on the same object, at substantially the same physical location.

11. A microwave barcode system comprising:

a barcode comprising a plurality of conductive wires mounted on a surface of an object;

a transmitter, comprising a dipole antenna, radiating microwave signals in the direction of the surface; and

,

a microwave reader, comprising a dipole antenna, positioned to receive the microwave signals passing through the surface wherein the reader senses an attenuation of the microwave signal caused by a resonant interaction between the microwave signals and the conductive wires.

12. The microwave barcode system of claim 11, wherein the microwave reader further comprises:

two conductive receiving elements; and

,

a detector diode connected to bridge the receiving elements.

13. The microwave barcode system of claim 11, wherein the plurality of conductive wires are comprised of a plurality of lengths wherein each unique length corresponds to a unique datum value.

14. The microwave barcode system of claim 13, wherein the conductive wires are mounted in a stand-up fashion, wherein each wire is mounted adjacent to and parallel to, but not touching, its at least one neighbor.

15. The microwave barcode system of claim 13, wherein the conductive wires are mounted in a lay-down fashion, wherein each wire is mounted coincident with an imaginary line which is also coincident with the remaining wires, and wherein the wires are mounted end-to-end with a gap surrounding each wire end.

16. The microwave barcode system of claim 13, wherein the barcode comprises:

a stand-up barcode wherein each wire is mounted adjacent to and parallel to, but not touching, its at least one neighbor; and

,

and a lay-down barcode wherein each wire is mounted coincident with an imaginary line which is also coincident with the remaining wires, and wherein the wires are mounted end-to-end with a gap surrounding each wire end.

17. The microwave barcode system of claim 11, wherein the plurality of conductive wires is comprised of equal length wires wherein each wire is mounted at an angle selected from a plurality of angles, and each unique angle corresponds to a unique datum value.

18. The microwave barcode system of claim 11, wherein the surface is an imaginary surface embedded within the object.

20. The method of claim 19 wherein the surface is an imaginary surface embedded within the object.

19. A method for reading microwave barcodes comprising:

mounting a barcode comprising a plurality of conductive wires on a surface of an object;

transmitting, from a dipole antenna, microwave signals in the direction of the surface; and

,

receiving, with a dipole antenna, the microwave signals passing through the surface and sensing an attenuation of the microwave signal caused by a resonant interaction between the microwave signals and the conductive wires.