Spatially selective UHF near field microstrip coupler device and RFID systems using device

• US 7,650,114 B2
• Filed: 06/05/2008
• Issued: 01/19/2010
• Est. Priority Date: 08/29/2003
• Status: Expired due to Term

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: ZIH Corp. (Zebra Technologies Corporation)
• Inventors: Gawelczyk, Robert, Donato, Daniel F., Tsirline, Boris Y., Hohberger, Clive P.
• Primary Examiner(s): Dao; Minh D
• Application Number:
  US12/133,801
• Publication Number:
  US 20090008448A1
• Time in Patent Office: 593 Days
• Field of Search: 455/41.1, 455/41.2, 455/151, 455/330, 340/10.1, 340/572.1, 340/10.5, 340/505, 343/749
• US Class Current: 455/41.2
• CPC Class Codes: G06K 1/12 otherwise than by punching
• CPC Class Codes: G06K 17/0025 the arrangement consisting of a wireless interrogation device in combination with a device for optically marking the record carrier
• 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 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications

Abstract

A system having a UHF RFID transceiver is adapted to communicate exclusively with a single electro-magnetically coupled transponder located in a predetermined confined transponder operating region. The system includes a near field coupling device comprising a plurality of lines connected in parallel with an unmatched load. The near field coupling device may be formed, for example on a printed circuit board with a plurality of electrically interconnected traces and a ground plane. The system establishes, at predetermined transceiver power levels, a mutual electro-magnetic coupling which is selective exclusively for a single transponder located in a defined transponder operating region. Also included are methods for selective communication with the transponder in an apparatus such as a printer-encoder.

Claims

1. A printer including a transceiver adapted to communicate with transponders, comprising:

a printhead;

a media conveyance adapted to transport a series of discrete media to said printhead and through a transponder operating region, at least some of said media including a transponder;

a near field coupler configured to generate a near field effect to couple with the transponder for data transfer;

the near field coupler having a plurality of lines electrically interconnected in parallel, and a spaced away ground plane.

2. The printer defined by claim 1 wherein the near field coupler is formed as traces on a printed circuit board.

3. The printer defined by claim 1 wherein the near field coupler has a characteristic impedance and the near field coupler is terminated by a terminating resistor having a different characteristic impedance.

4. The printer defined by claim 1 wherein the plurality of lines are arranged parallel to each other.

5. The printer defined by claim 1 wherein at least one of the plurality of lines has a zig-zag configuration.

6. The printer defined by claim 1 wherein said printhead is positioned and configured to print on or adjacent said transponder while it is still in said transponder operating region.

7. The printer defined by claim 1 wherein said printhead is positioned and configured to print on or adjacent said transponder when it is outside of said transponder operating region.

8. The printer defined by claim 1 adapted to feed a web of spaced transponders through said transponder operating region, and wherein said printer communicates with a transponder located in said transponder operating region but concurrently not with another transponder located outside of said transponder operating region.